Dissertations / Theses on the topic 'Space-Time Block Codes'

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1

Pak, Anne On-Yi 1977. "Euclidean space codes as space-time block codes." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/86722.

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2

Ali, Saajed. "Concatenation of Space-Time Block Codes with ConvolutionalCodes." Thesis, Virginia Tech, 2004. http://hdl.handle.net/10919/9724.

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Multiple antennas help in combating the destructive effects of fading as well as improve the spectral efficiency of a communication system. Receive diversity techniques like maximal ratio receive combining have been popular means of introducing multiple antennas into communication systems. Space-time block codes present a way of introducing transmit diversity into the communication system with similar complexity and performance as maximal ratio receive combining. In this thesis we study the performance of space-time block codes in Rayleigh fading channel. In particular, the quasi-static assumption on the fading channel is removed to study how the space-time block coded system behaves in fast fading. In this context, the complexity versus performance trade-off for a space-time block coded receiver is studied. As a means to improve the performance of space-time block coded systems concatenation by convolutional codes is introduced. The improvement in the diversity order by the introduction of convolutional codes into the space-time block coded system is discussed. A general analytic expression for the error performance of a space-time block coded system is derived. This expression is utilized to obtain general expressions for the error performance of convolutionally concatenated space-time block coded systems utilizing both hard and soft decision decoding. Simulation results are presented and are compared with the analytical results.
Master of Science
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3

Liao, Huiyong. "Lattice based space-time block codes for MIMO system." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 155 p, 2007. http://proquest.umi.com/pqdweb?did=1251904861&sid=2&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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4

Sengupta, Avik. "Redundant residue number system based space-time block codes." Thesis, Kansas State University, 2012. http://hdl.handle.net/2097/14111.

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Master of Science
Department of Electrical and Computer Engineering
Balasubramaniam Natarajan
Space-time coding (STC) schemes for Multiple Input Multiple Output (MIMO) systems have been an area of active research in the past decade. In this thesis, we propose a novel design of Space-Time Block Codes (STBCs) using Redundant Residue Number System (RRNS) codes, which are ideal for high data rate communication systems. Application of RRNS as a concatenated STC scheme to a MIMO wireless communication system is the main motivation for this work. We have optimized the link between residues and complex constellations by incorporating the “Direct Mapping” scheme, where residues are mapped directly to Gray coded constellations. Knowledge of apriori probabilities of residues is utilized to implement a probability based “Distance-Aware Direct Mapping” (DA) scheme, which uses a set-partitioning approach to map the most probable residues such that they are separated by the maximum possible distance. We have proposed an “Indirect Mapping” scheme, where we convert the residues back to bits before mapping them. We have also proposed an adaptive demapping scheme which utilizes the RRNS code structure to reduce the ML decoding complexity and improve the error performance. We quantify the upper bounds on codeword and bit error probabilities of both Systematic and Non-systematic RRNS-STBC and characterize the achievable coding and diversity gains assuming maximum likelihood decoding (MLD). Simulation results demonstrate that the DA Mapping scheme provides performance gain relative to a Gray coded direct mapping scheme. We show that Systematic RRNS-STBC codes provide superior performance compared to Nonsystematic RRNS-STBC, for the same code parameters, owing to more efficient binary to residue mapping. When compared to other concatenated STBC and Orthogonal STBC (OSTBC) schemes, the proposed system gives better performance at low SNRs.
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5

Baker, Dirk A. "Space-time block coding with imperfect channel estimates." Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=1843.

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Thesis (M.S.)--West Virginia University, 2001.
Title from document title page. Document formatted into pages; contains iv, 74 p. : ill. Includes abstract. Includes bibliographical references (p. 73-74).
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6

Sinnokrot, Mohanned Omar. "Space-time block codes with low maximum-likelihood decoding complexity." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/31752.

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Thesis (Ph.D)--Electrical and Computer Engineering, Georgia Institute of Technology, 2010.
Committee Chair: Barry, John; Committee Co-Chair: Madisetti, Vijay; Committee Member: Andrew, Alfred; Committee Member: Li, Ye; Committee Member: Ma, Xiaoli; Committee Member: Stuber, Gordon. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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7

Lin, Rui. "Hybrid ARQ Schemes for Non-orthogonal Space-time Block Codes." Thesis, University of Canterbury. Electrical and Computer Engineering, 2007. http://hdl.handle.net/10092/1183.

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Automatic Repeat-reQuest (ARQ) schemes are extensively used in communication systems and computer networks to achieve reliable transmission. Using space-time codes (STCs) with multiple input multiple output (MIMO) or multiple input single output (MISO) systems is an effective way to combat multipath fading, which is the most severe impairment for wireless communication systems. STCs are designed to use the rich scattering multipath environment provided by using multiple transmit antennas. The work done in this thesis focuses on the use of ARQ schemes with non-orthogonal space-time block codes (NOSTBCs) based on Reed Solomon codes. The truncated-selective ARQ (TS-ARQ) scheme is considered and three novel hybrid ARQ (HARQ) schemes are proposed. Simulation results reveal that, compared to using TS-ARQ with orthogonal space-time block codes (OSTBCs), using NOSTBCs with any of the three proposed HARQ schemes can provide significant gains in terms of dropped packet rate and spectral efficiency at the cost of increased decoding complexity. The performance can be further improved by using the water filling principle to adaptively allocate transmit power among transmit antennas.
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8

Oruç, Özgür Altınkaya Mustafa Aziz. "Differential and coherent detection schemes for space-time block codes/." [s.l.]: [s.n.], 2002. http://library.iyte.edu.tr/tezler/master/elektrikveelektronikmuh/T000133.pdf.

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9

Acharya, Om Nath, and Sabin Upadhyaya. "Space Time Coding For Wireless Communication." Thesis, Linnéuniversitetet, Institutionen för datavetenskap, fysik och matematik, DFM, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-19424.

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As the demand of high data rate is increasing, a lot of research is being conducted in the field of wireless communication. A well-known channel coding technique called Space-Time Coding has been implemented in the wireless Communication systems using multiple antennas to ensure the high speed communication as well as reliability by exploiting limited spectrum and maintaining the power. In this thesis, Space-Time Coding is discussed along with other related topics with special focus on Alamouti Space-Time Block Code. The Alamouti Codes show good performance in terms of bit error rate over Rayleigh fading channel. The performance of Altamonte’s code and MIMO capacity is evaluated by using MATLAB simulation.
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10

Chu, Alice Pin-Chen. "High-Rate Space-Time Block Codes in Frequency-Selective Fading Channels." Thesis, University of Canterbury. Electrical and Computer Engineering, 2012. http://hdl.handle.net/10092/10360.

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The growing popularity of wireless communications networks has resulted in greater bandwidth contention and therefore spectrally efficient transmission schemes are highly sought after by designers. Space-time block codes (STBCs) in multiple-input, multiple-output (MIMO) systems are able to increase channel capacity as well as reduce error rate. A general linear space-time structure known as linear dispersion codes (LDCs) can be designed to achieve high-data rates and has been researched extensively for flat fading channels. However, very little research has been done on frequency-selective fading channels. The combination of ISI, signal interference from other transmitters and noise at the receiver mean that maximum likelihood sequence estimation (MLSE) requires high computational complexity. Detection schemes that can mitigate the signal interference can significantly reduce the complexity and allow intersymbol interference (ISI) equalization to be performed by a Viterbi decoder. In this thesis, detection of LDCs on frequency-selective channels is investigated. Two predominant detection schemes are investigated, namely linear processing and zero forcing (ZF). Linear processing depends on code orthogonality and is only suited for short channels and small modulation schemes. ZF cancels interfering signals when a sufficient number of receive antennas is deployed. However, this number increases with the channel length. Channel decay profiles are investigated for high-rate LDCs to ameliorate this limitation. Performance improves when the equalizer assumes a shorter channel than the actual length provided the truncated taps carry only a small portion of the total channel power. The LDC is also extended to a multiuser scenario where two independent users cooperate over half-duplex frequency-selective channels to achieve cooperative gain. The cooperative scheme transmits over three successive block intervals. Linear and zero-forcing detection are considered.
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11

Pau, Nicholas. "Robust High Throughput Space-Time Block Coded MIMO Systems." Thesis, University of Canterbury. Electrical and Computer Engineering, 2007. http://hdl.handle.net/10092/1167.

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In this thesis, we present a space-time coded system which achieves high through- put and good performance with low processing delay using low-complexity detection and decoding. Initially, Hamming codes are used in a simple interleaved bit-mapped coded modulation structure (BMCM). This is concatenated with Alamouti's or- thogonal space-time block codes. The good performance achieved by this system indicates that higher throughput is possible while maintaining performance. An analytical bound for the performance of this system is presented. We also develop a class of low density parity check codes which allows flexible "throughput versus performance" tradeoffs. We then focus on a Rate 2 quasi-orthogonal space-time block code structure which enables us to achieve an overall throughput of 5.6 bits/symbol period with good performance and relatively simple decoding using iterative parallel interference cancellation. We show that this can be achieved through the use of a bit-mapped coded modulation structure using parallel short low density parity check codes. The absence of interleavers here reduces processing delay significantly. The proposed system is shown to perform well on flat Rayleigh fading channels with a wide range of normalized fade rates, and to be robust to channel estimation errors. A comparison with bit-interleaved coded modulation is also provided (BICM).
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12

Potter, Chris, Kurt Kosbar, and Adam Panagos. "Effects of Synchronization Error on Space Time Block Codes Equipped with FSK Waveforms." International Foundation for Telemetering, 2009. http://hdl.handle.net/10150/605966.

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ITC/USA 2009 Conference Proceedings / The Forty-Fifth Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2009 / Riviera Hotel & Convention Center, Las Vegas, Nevada
Space-time Coding (STC) for Multiple-Input Multiple-Output (MIMO) wireless communication systems is an effective technique for providing robust wireless link performance in telemetry systems. This paper investigates the degradation in system performance when synchronization errors between the transmitter and receiver are present. Specifically, expressions that quantify the increase in symbol-error-rate as a function of symbol synchronization error are derived for a two-transmit and single receive antenna MISO system using binary frequency shift keying waveforms. These results are then extended to the MIMO case. The analytic results are verified with simulation results that show close agreement between the theoretical expressions and Monte Carlo simulation runs.
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13

Colavito, Leonard R. "Evaluation of Space-Time Block Codes Under Controlled Fading Conditions Using Hardware Simulation." Diss., Temple University Libraries, 2010. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/66976.

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Engineering
Ph.D.
Space time block codes (STBC) are a type of multiple input multiple output (MIMO) communications system that encode blocks of information into symbol sequences sent simultaneously from multiple antennas. MIMO communications systems have shown channel capacity improvement in multipath digital communications environments. The STBC class of MIMO communications systems can be easily decoded using linear combination and is resilient in the face of multipath channel effects. MIMO systems have traditionally been studied using theoretical analyses, simulations and real signal based experiments. Probabilistic models simulate channel effects as random variables, but are only estimates of actual conditions. Real signal experiments evaluate system performance under real-world conditions, but are not readily repeatable. Both modeling methods evaluate system performance in terms of the aggregate results. This dissertation research presents an approach that introduces controlled attenuation and delay to probabilistic channel models. This method allows the evaluation of MIMO system performance under specific channel conditions. The approach is demonstrated with a hardware accelerated STBC system model that is used to evaluate the performance of a MIMO system under controlled path conditions. The STBC system model utilizes a Xilinix® programmable gate array (PGA) device as a hardware accelerator. The model exploits the parallel processing capability of the PGA to simulate a nine path channel model and a three antenna rate ½ STBC. Novel implementations are developed for the additive white Gaussian noise (AWGN) sources and the linear MIMO decoding in PGA hardware. The model allows specification of overall noise and multipath fading effects for the channel as well as attenuation and phase delay for each channel path. Performance of the communications system is evaluated in terms of bit error rate (BER) versus signal-to-noise ratio (SNR). Hardware acceleration greatly reduces the time required to obtain simulation results. Reduced simulation time improves the use of the model by allowing evaluation of system performance under a greater number of conditions, greater performance curve resolution and evaluation at lower BER. The processing rate of the hardware accelerated model is compared to an equivalent software model. The model also provides an extensible platform for future research in communications theory.
Temple University--Theses
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14

Owojaiye, Gbenga Adetokunbo. "Design and performance analysis of distributed space time coding schemes for cooperative wireless networks." Thesis, University of Hertfordshire, 2012. http://hdl.handle.net/2299/8970.

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In this thesis, space-time block codes originally developed for multiple antenna systems are extended to cooperative multi-hop networks. The designs are applicable to any wireless network setting especially cellular, adhoc and sensor networks where space limitations preclude the use of multiple antennas. The thesis first investigates the design of distributed orthogonal and quasi-orthogonal space time block codes in cooperative networks with single and multiple antennas at the destination. Numerical and simulation results show that by employing multiple receive antennas the diversity performance of the network is further improved at the expense of slight modification of the detection scheme. The thesis then focuses on designing distributed space time block codes for cooperative networks in which the source node participates in cooperation. Based on this, a source-assisting strategy is proposed for distributed orthogonal and quasi-orthogonal space time block codes. Numerical and simulation results show that the source-assisting strategy exhibits improved diversity performance compared to the conventional distributed orthogonal and quasi-orthogonal designs.Motivated by the problem of channel state information acquisition in practical wireless network environments, the design of differential distributed space time block codes is investigated. Specifically, a co-efficient vector-based differential encoding and decoding scheme is proposed for cooperative networks. The thesis then explores the concatenation of differential strategies with several distributed space time block coding schemes namely; the Alamouti code, square-real orthogonal codes, complex-orthogonal codes, and quasiorthogonal codes, using cooperative networks with different number of relay nodes. In order to cater for high data rate transmission in non-coherent cooperative networks, differential distributed quasi-orthogonal space-time block codes which are capable of achieving full code-rate and full diversity are proposed. Simulation results demonstrate that the differential distributed quasi-orthogonal space-time block codes outperform existing distributed space time block coding schemes in terms of code rate and bit-error-rate performance. A multidifferential distributed quasi-orthogonal space-time block coding scheme is also proposed to exploit the additional diversity path provided by the source-destination link.A major challenge is how to construct full rate codes for non-coherent cooperative broadband networks with more than two relay nodes while exploiting the achievable spatial and frequency diversity. In this thesis, full rate quasi-orthogonal codes are designed for noncoherent cooperative broadband networks where channel state information is unavailable. From this, a generalized differential distributed quasi-orthogonal space-frequency coding scheme is proposed for cooperative broadband networks. The proposed scheme is able to achieve full rate and full spatial and frequency diversity in cooperative networks with any number of relays. Through pairwise error probability analysis we show that the diversity gain of the proposed scheme can be improved by appropriate code construction and sub-carrier allocation. Based on this, sufficient conditions are derived for the proposed code structure at the source node and relay nodes to achieve full spatial and frequency diversity. In order to exploit the additional diversity paths provided by the source-destination link, a novel multidifferential distributed quasi-orthogonal space-frequency coding scheme is proposed. The overall objective of the new scheme is to improve the quality of the detected signal at the destination with negligible increase in the computational complexity of the detector.Finally, a differential distributed quasi-orthogonal space-time-frequency coding scheme is proposed to cater for high data rate transmission and improve the performance of noncoherent cooperative broadband networks operating in highly mobile environments. The approach is to integrate the concept of distributed space-time-frequency coding with differential modulation, and employ rotated constellation quasi-orthogonal codes. From this, we design a scheme which is able to address the problem of performance degradation in highly selective fading environments while guaranteeing non-coherent signal recovery and full code rate in cooperative broadband networks. The coding scheme employed in this thesis relaxes the assumption of constant channel variation in the temporal and frequency dimensions over long symbol periods, thus performance degradation is reduced in frequencyselective and time-selective fading environments. Simulation results illustrate the performance of the proposed differential distributed quasi-orthogonal space-time-frequency coding scheme under different channel conditions.
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15

Potter, Chris, Kurt Kosbar, and Adam Panagos. "Hardware Discussion of a MIMO Wireless Communication System Using Orthogonal Space Time Block Codes." International Foundation for Telemetering, 2008. http://hdl.handle.net/10150/606194.

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ITC/USA 2008 Conference Proceedings / The Forty-Fourth Annual International Telemetering Conference and Technical Exhibition / October 27-30, 2008 / Town and Country Resort & Convention Center, San Diego, California
Although multiple-input multiple-output (MIMO) systems have become increasingly popular, the existence of real time results to compare with those predicted by theory is still surprisingly limited. In this work the hardware description of a MIMO wireless communication system using orthogonal space time block codes (OSTBC) is discussed for two antennas at both the transmitter and receiver. A numerical example for a frequency flat time correlated channel is given to show the impact of channel estimation.
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16

Grabner, Mitchell J. "A Cognitive MIMO OFDM Detector Design for Computationally Efficient Space-Time Decoding." Thesis, University of North Texas, 2019. https://digital.library.unt.edu/ark:/67531/metadc1538696/.

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In this dissertation a computationally efficient cognitive multiple-input multiple-output (MIMO) orthogonal frequency division duplexing (OFDM) detector is designed to decode perfect space-time coded signals which are able maximize the diversity and multiplexing properties of a rich fading MIMO channel. The adaptive nature of the cognitive detector allows a MIMO OFDM communication system to better meet to needs of future wireless communication networks which require both high reliability and low run-time complexity depending on the propagation environment. The cognitive detector in conjunction with perfect space-time coding is able to achieve up to a 2 dB bit-error rate (BER) improvement at low signal-to-noise ratio (SNR) while also achieving comparable runtime complexity in high SNR scenarios.
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17

Delestre, Fabien. "Channel estimation and performance analysis of MIMO-OFDM communications using space-time and space-frequency coding schemes." Thesis, University of Hertfordshire, 2011. http://hdl.handle.net/2299/6397.

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This thesis is concerned with channel estimation and data detection of MIMO-OFDM communication systems using Space-Time Block Coding (STBC) and Space-Frequency Block Coding (SFBC) under frequency selective channels. A new iterative joint channel estimation and signal detection technique for both STBC-OFDM and SFBC-OFDM systems is proposed. The proposed algorithm is based on a processive sequence of events for space time and space frequency coding schemes where pilot subcarriers are used for channel estimation in the first time instant, and then in the second time instant, the estimated channel is used to decode the data symbols in the adjacent data subcarriers. Once data symbols are recovered, the system recursively performs a new channel estimation using the decoded data symbols as pilots. The iterative process is repeated until all MIMO-OFDM symbols are recovered. In addition, the proposed channel estimation technique is based on the maximum likelihood (ML) approach which offers linearity and simplicity of implementation. Due to the orthogonality of STBC and SFBC, high computation efficiency is achieved since the method does not require any matrix inversion for estimation and detection at the receiver. Another major novel contribution of the thesis is the proposal of a new group decoding method that reduces the processing time significantly via the use of sub-carrier grouping for transmitted data recovery. The OFDM symbols are divided into groups to which a set of pilot subcarriers are assigned and used to initiate the channel estimation process. Designated data symbols contained within each group of the OFDM symbols are decoded simultaneously in order to improve the decoding duration. Finally, a new mixed STBC and SFBC channel estimation and data detection technique with a joint iterative scheme and a group decoding method is proposed. In this technique, STBC and SFBC are used for pilot and data subcarriers alternatively, forming the different combinations of STBC/SFBC and SFBC/STBC. All channel estimation and data detection methods for different MIMO-OFDM systems proposed in the thesis have been simulated extensively in many different scenarios and their performances have been verified fully.
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18

Leuschner, Jeff. "A new generic maximum-likelihood metric expression for space-time block codes with applications to decoding." Thesis, Kingston, Ont. : [s.n.], 2007. http://hdl.handle.net/1974/633.

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19

Diewald, Jens [Verfasser], Detlev [Akademischer Betreuer] Hoffmann, and Thomas [Gutachter] Unger. "A new approach to noncoherent space-time block codes / Jens Diewald ; Gutachter: Thomas Unger ; Betreuer: Detlev Hoffmann." Dortmund : Universitätsbibliothek Dortmund, 2017. http://d-nb.info/1141379813/34.

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20

Chi, Xuan. "The Impact of Channel Estimation Error on Space-Time Block and Trellis Codes in Flat and Frequency Selective Channels." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/33963.

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Recently multiple antenna systems have received significant attention from researchers as a means to improve the energy and spectral efficiency of wireless systems. Among many classes of schemes, Space-Time Block codes (STBC) and Space-Time Trellis codes (STTC) have been the subject of many investigations.

Both techniques provide a means for combatting the effects of multipath fading without adding much complexity to the receiver. This is especially useful in the downlink of wireless systems. In this thesis we investigate the impact of channel estimation error on the performance of both STBC and STTC.

Channel estimation is especially important to consider in multiple antenna systems since (A) for coherent systems there are more channels to estimate due to multiple antennas and (B) the decoupling of data streams relies on correct channel estimation. The latter effect is due to the intentional cross-talk introduced into STBC.
Master of Science

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21

Alotaibi, Faisal T. "Distributed space-time block coding in cooperative relay networks with application in cognitive radio." Thesis, Loughborough University, 2012. https://dspace.lboro.ac.uk/2134/10965.

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Spatial diversity is an effective technique to combat the effects of severe fading in wireless environments. Recently, cooperative communications has emerged as an attractive communications paradigm that can introduce a new form of spatial diversity which is known as cooperative diversity, that can enhance system reliability without sacrificing the scarce bandwidth resource or consuming more transmit power. It enables single-antenna terminals in a wireless relay network to share their antennas to form a virtual antenna array on the basis of their distributed locations. As such, the same diversity gains as in multi-input multi-output systems can be achieved without requiring multiple-antenna terminals. In this thesis, a new approach to cooperative communications via distributed extended orthogonal space-time block coding (D-EO-STBC) based on limited partial feedback is proposed for cooperative relay networks with three and four relay nodes and then generalized for an arbitrary number of relay nodes. This scheme can achieve full cooperative diversity and full transmission rate in addition to array gain, and it has certain properties that make it alluring for practical systems such as orthogonality, flexibility, low computational complexity and decoding delay, and high robustness to node failure. Versions of the closed-loop D-EO-STBC scheme based on cooperative orthogonal frequency division multiplexing type transmission are also proposed for both flat and frequency-selective fading channels which can overcome imperfect synchronization in the network. As such, this proposed technique can effectively cope with the effects of fading and timing errors. Moreover, to increase the end-to-end data rate, this scheme is extended for two-way relay networks through a three-time slot framework. On the other hand, to substantially reduce the feedback channel overhead, limited feedback approaches based on parameter quantization are proposed. In particular, an optimal one-bit partial feedback approach is proposed for the generalized D-O-STBC scheme to maximize the array gain. To further enhance the end-to-end bit error rate performance of the cooperative relay system, a relay selection scheme based on D-EO-STBC is then proposed. Finally, to highlight the utility of the proposed D-EO-STBC scheme, an application to cognitive radio is studied.
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Chi, Zhanjiang. "Performance Analysis of Maximal-Ratio Combining and Space-Time Block Codes with Transmit Antenna Selection over Nakagami-m Fading Channels." Thesis, The University of Sydney, 2007. http://hdl.handle.net/2123/2012.

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The latest wireless communication techniques such as highspeed wireless internet application demand higher data rates and better quality of service (QoS). However, transmission reliability is still degraded by harsh propagation channels. Multiple-input multiple-output (MIMO) systems can increase the system capacity and improve transmission reliability. By transmitting multiple copies of data, a MIMO system can effectively combat the effects of fading. Due to the high hardware cost of a MIMO system, antenna selection techniques have been applied in MIMO system design to reduce the system complexity and cost. The Nakagami-m distribution has been considered for MIMO channel modeling since a wide range of fading channels, from severe to moderate, can be modeled by using Nakagami-m distribution. The Rayleigh distribution is a special case of the Nakagami-m distribution. In this thesis, we analyze the error performance of two MIMO schemes: maximal-ratio combining with transmit antenna selection (the TAS/MRC scheme) and space-time block codes with transmit antenna selection (the TAS/STBC scheme) over Nakagami-m fading channels. In the TAS/MRC scheme, one of multiple transmit antennas, which maximizes the total received signal-to-noise ratio (SNR), is selected for uncoded data transmission. First we use a moment generating function based (MGF-based) approach to derive the bit error rate (BER) expressions for binary phase shift keying (BPSK), the symbol error rate (SER) expressions for M-ray phase shift keying (MPSK) and M-ray quadrature amplitude modulation (MQAM) of the TAS/MRC scheme over Nakagami-m fading channels with arbitrary and integer fading parameters m. The asymptotic performance is also investigated. It is revealed that the asymptotic diversity order is equal to the product of the Nakagami fading parameter m, the number of transmit antenna Lt and the number of receive antenna Lr as if all transmit antenna were used. Then a Gaussian Q-functions approach is used to investigate the error performance of the TAS/STBC scheme over Nakagami-m fading channels. In the TAS/STBC scheme, two transmit antennas, which maximize the output SNR, are selected for transmission. The exact and asymptotic BER expressions for BPSK are obtained for the TAS/STBC schemes with three and four transmit antennas. It is shown that the TAS/STBC scheme can provide a full diversity order of mLtLr.
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Chi, Zhanjiang. "Performance Analysis of Maximal-Ratio Combining and Space-Time Block Codes with Transmit Antenna Selection over Nakagami-m Fading Channels." School of Electrical and Information Engineering, 2007. http://hdl.handle.net/2123/2012.

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Master of Engineering (Research)
The latest wireless communication techniques such as highspeed wireless internet application demand higher data rates and better quality of service (QoS). However, transmission reliability is still degraded by harsh propagation channels. Multiple-input multiple-output (MIMO) systems can increase the system capacity and improve transmission reliability. By transmitting multiple copies of data, a MIMO system can effectively combat the effects of fading. Due to the high hardware cost of a MIMO system, antenna selection techniques have been applied in MIMO system design to reduce the system complexity and cost. The Nakagami-m distribution has been considered for MIMO channel modeling since a wide range of fading channels, from severe to moderate, can be modeled by using Nakagami-m distribution. The Rayleigh distribution is a special case of the Nakagami-m distribution. In this thesis, we analyze the error performance of two MIMO schemes: maximal-ratio combining with transmit antenna selection (the TAS/MRC scheme) and space-time block codes with transmit antenna selection (the TAS/STBC scheme) over Nakagami-m fading channels. In the TAS/MRC scheme, one of multiple transmit antennas, which maximizes the total received signal-to-noise ratio (SNR), is selected for uncoded data transmission. First we use a moment generating function based (MGF-based) approach to derive the bit error rate (BER) expressions for binary phase shift keying (BPSK), the symbol error rate (SER) expressions for M-ray phase shift keying (MPSK) and M-ray quadrature amplitude modulation (MQAM) of the TAS/MRC scheme over Nakagami-m fading channels with arbitrary and integer fading parameters m. The asymptotic performance is also investigated. It is revealed that the asymptotic diversity order is equal to the product of the Nakagami fading parameter m, the number of transmit antenna Lt and the number of receive antenna Lr as if all transmit antenna were used. Then a Gaussian Q-functions approach is used to investigate the error performance of the TAS/STBC scheme over Nakagami-m fading channels. In the TAS/STBC scheme, two transmit antennas, which maximize the output SNR, are selected for transmission. The exact and asymptotic BER expressions for BPSK are obtained for the TAS/STBC schemes with three and four transmit antennas. It is shown that the TAS/STBC scheme can provide a full diversity order of mLtLr.
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24

Abaza, Mohamed. "Cooperative MIMO techniques for outdoor optical wireless communication systems." Thesis, Brest, 2015. http://www.theses.fr/2015BRES0073/document.

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Au cours de la dernière décennie, les communications optiques en espace libre (FSO) ont pris de l’ampleur dans les deux domaines académiques et industriels. L’importance de FSO s’appuie sur la possibilité de faire un système de transmission économique et écologique avec un débit élevé et sans licence à l’opposition des systèmes de transmission radiofréquences (RF). Dans la plupart des travaux antécédents sur les systèmes multi-émetteurs, seulement les canaux décorrélés ont été considérés. Un canal décorrélé nécessite un espace suffisant entre les émetteurs. Cette condition devient difficile et non-réalisable dans certaines applications. Pour cette raison, nos études se focalisent sur les performances des codes à répétition RC (Repitition Codes) et les codes OSTBC (Orthogonal Space-Time Block Codes) dans des canaux log-normaux corrélés en utilisant une modulation d’intensité et une détection directe (IM/DD). En addition, les effets des différentes conditions météorologiques sur le taux d’erreur moyen (ABER) sont étudiés. Les systèmes FSO à multi-entrées/ multi-sorties MIMO (Multiple-Input Multiple-Output) avec une modulation SSK (Space Shift Keying) ont été abordés. Les résultats obtenus montrent que la SSK est supérieure aux RC avec une modulation d’impulsion (Multiple Pulse Amplitude Modulation) pour toute efficacité spectrale égale ou supérieure à 4 bit/s/Hz. Nous avons aussi analysé les performances d’un système à sauts multiples (Multi-Hop) et des relais à transmission directe (forward relays). Nos simulations montrent que le système ainsi considéré est efficace pour atténuer les effets météorologiques et les pertes géométriques dans les systèmes de communication FSO. Nous avons montré qu’un tel système avec plusieurs entrées et une sortie (MISO, i.e. multiple-input single-output) à sauts multiples est supérieur à un système MISO avec un lien direct (direct link) avec une forte atténuation. Pour satisfaire la demande croissante des réseaux de communication à débits élevés, la communauté scientifique s'intéresse de plus en plus aux systèmes FSO avec des relais full-duplex (FD). Pour ces derniers systèmes, nous avons étudié la probabilité d'erreur moyenne (ABER) et nous avons analysé leurs performances. En considérant des différentes conditions de transmission, les performances de relais FD ont été comparées à celles d'un système avec un lien direct ou des relais half-duplex. Les résultats obtenus montrent que les relais FD ont le minimum ABER. En conséquence, les résultats obtenus dans cette thèse sont très prometteurs pour la prochaine génération de FSO
Free-space optical (FSO) communication has been the subject of ongoing research activities and commercial attention in the past few years. Such attention is driven by the promise of high data rate, license-free operation, and cheap and ecological friendly means of communications alternative to congested radio frequency communications. In most previous work considering multiple transmitters, uncorrelated channel conditions have been considered. An uncorrelated channel requires sufficient spacing between transmitters. However, this can be difficult and may not be always feasible in some applications. Thereby, this thesis studies repetition codes (RCs) and orthogonal space-time block codes performance in correlated log-normal FSO channels using intensity modulation and direct detection (IM/DD). Furthermore, the effect of different weather conditions on the average bit error rate (ABER) performance of the FSO links is studied. Multiple-input multiple-output (MIMO) FSO communication systems using space shift keying (SSK) modulation have been also analyzed. Obtained results show that SSK is a potential technique for spectral efficiencies equal or greater than 4 bits/s/Hz as compared to RCs with multiple pulse amplitude modulations. The performance analysis of a multi-hop decode and forward relays for FSO communication system using IM/DD is also considered in this thesis. It is shown that multi-hop is an efficient technique to mitigate atmospheric turbulence and different weather attenuation effects and geometric losses in FSO communication systems. Our simulation results show that multiple-input single-output (MISO) multi-hop FSO systems are superior to direct link and MISO systems over links exhibiting high attenuation. Meeting the growing demand for higher data rates communication networks, a system with full-duplex (FD) relays is considered. For such a system, the outage probability and the ABER performance are analyzed under different turbulence conditions, misalignment error and path loss effects. FD relays are compared with the direct link and half-duplex relays. Obtained results show that FD relays have the lowest ABER and the outage probability as compared to the two other systems. Finally, the obtained results in this thesis are very promising towards the next generation of FSO systems
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25

Saglam, Halil Derya. "Simulation performance of multiple-input multiple-output systems employing single-carrier modulation and orthogonal frequency division multiplexing." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Dec%5FSaglam.pdf.

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Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, Dec. 2004.
Thesis advisor(s): Murali Tummala, Roberto Cristi. Includes bibliographical references (p. 69-71). Also available online.
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26

Phan, Hoc. "Performance Assessment of Cooperative Relay Networks with Advanced Radio Transmission Techniques." Doctoral thesis, Blekinge Tekniska Högskola, Sektionen för datavetenskap och kommunikation, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-00549.

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In the past decade, cooperative communications has been emerging as a pertinent technology for the current and upcoming generations of mobile communication infrastructure. The indispensable benefits of this technology have motivated numerous studies from both academia and industry on this area. In particular, cooperative communications has been developed as a means of alleviating the effect of fading and hence improve the reliability of wireless communications. The key idea behind this technique is that communication between the source and destination can be assisted by several intermediate nodes, so-called relay nodes. As a result, cooperative communication networks can enhance the reliability of wireless communications where the transmitted signals are severely impaired because of fading. In addition, through relaying transmission, communication range can be extended and transmit power of each radio terminal can be reduced as well. The objective of this thesis is to analyze the system performance of cooperative relay networks integrating advanced radio transmission techniques and using the two major relaying protocols, i.e., decode-and-forward (DF) and amplify-and-forward (AF). In particular, the radio transmission techniques that are considered in this thesis include multiple-input multiple-output (MIMO) systems and orthogonal space-time block coding (OSTBC) transmission, adaptive transmission, beamforming transmission, coded cooperation, and cognitive radio transmission. The thesis is divided into an introduction section and six parts based on peer-reviewed journal articles and conference papers. The introduction provides the readers with some fundamental background on cooperative communications along with several key concepts of cognitive radio systems. In the first part, performance analysis of cooperative single and multiple relay networks using MIMO and OSTBC transmission is presented wherein the diversity gain, coding gain, outage probability, symbol error rate, and channel capacity are assessed. It is shown that integrating MIMO and OSTBC transmission into cooperative relay networks provides full diversity gain. In the second part, the performance benefits of MIMO relay networks with OSTBC and adaptive transmission strategies are investigated. In the third part, the performance improvement with respect to outage probability of coded cooperation applied to opportunistic DF relay networks over conventional cooperative networks is shown. In the fourth part, the effects of delay of channel state information feedback from the destination to the source and co-channel interference on system performance is analyzed for beamforming AF relay networks. In the fifth part, cooperative diversity is investigated in the context of an underlay cognitive AF relay network with beamforming. In the sixth part, finally, the impact of the interference power constraint on the system performance of multi-hop cognitive AF relay networks is investigated.
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27

CHANG, CHING-YEN, and 張淨嚴. "Multilevel Product-Coded Space-Time Block Codes." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/p34e56.

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碩士
國立臺北科技大學
電機工程系
107
Nowadays, the communication system is required to have high performance, high stability and high reliability. In this thesis, we use space-time block codes in the wireless communication system. An expanded QPSK signal set is partitioned into five levels. Then, multilevel product codes are used as the component codes. Simulation results are performed to verify the error performance.
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28

Chou, Feng-Chih, and 周逢智. "Multilevel Space-Time Block Codes." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/30570619539849096824.

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碩士
中原大學
電機工程研究所
95
The multipath wireless channel suffers severe attenuation. The effective techniques to mitigate multipath fading are time and frequency diversity. In most situations, the wireless channel is slow varying and frequency non-selective. Hence, antenna diversity is a practical technique for reducing the effect of multipath fading. Multiple input multiple output wireless channels can introduce spatial diversity and increased information capacity. These results have motivated a new area in error correcting codes. Space-time codeing(STC) schemes combine the channel code design and the use of multiple transmit antennas. With combining Multi-level coding technique and set partition of space-time block code set, We will propose a novel design of space-time block codes. Using Multi-level coding technique can get lower complexity and the better performance.
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29

Li, Ssu-Hsien, and 李思賢. "Concatenation of Turbo Product Codes and Space Time Block Codes." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/42h364.

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碩士
中原大學
電機工程研究所
92
Abstract The multipath wireless channel suffers severe attenuation. The Effective techniques to mitigate multipath fading are time and frequency diversity. Foschini,Gans and Telatar proved that multiple input multiple output can introduce spatial diversity and increased information capacity. These results have motivated a new area in error correcting codes . Space-Time Coding (STC) schemes can combine the channel code design and the use of multiple transmit antennas . The Space Time Trellis Codes (STTC) proposed by Tarkoh combine the trellis coding with symbol mapping into multiple transmit antennas . The Coding scheme expansion is done in antenna space. The Turbo Codes proposed by Berrou have powerful error correcting abilities. It would be benefit to design turbo codes for multiple antenna systems. To design space-time turbo codes with maximum space diversity and outstanding performance is still an open question. The Turbo Codes exhibited a troublesome error floor. Besides, the MAP algorithm which performs maximum likelihood bit estimation has a very large computation complexity . Recently turbo product codes (TPC) have been proposed . It can proved the performance of turbo codes. It is expected that TPC for multiple antenna systems would be powerful coding schemes with maximum diversity gain and large coding gain.
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Tarasak, Poramate. "Improving performance of differential space-time block codes." 2004. http://hdl.handle.net/1828/359.

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Chuang, Ya-Shen, and 莊雅善. "Differential Space-Time Block Codes under Rayleigh Fading." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/70099555865287744871.

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碩士
國立成功大學
電機工程學系碩博士班
93
Space-time coding and modulation exploit the presence of multiple transmit antennas to improve the performance on multipath radio channels. Various space-time coding schemes have been proposed. However so far, most research on space-time coding has assumed that perfect estimates of current channel fading conditions are available at the receiver. However, in certain situations, we may want to forego channel estimation in order to reduce the complexity and cost of the handset, or perhaps fading conditions change so rapidly that channel estimation is difficult or requires too many training symbols.  The thesis presents several practical, feasible, and simple transmission schemes for exploiting diversity given by multiple transmit antennas when neither the transmitter nor the receiver has access to channel state information. The new detection scheme can use equal energy constellations and encoding is simple. At the receiver, decoding is achieved with low decoding complexity. The transmission requires no channel state side information at the receiver. The schemes can be considered as the extension of differential detection schemes to two transmit antennas.
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32

Cheng, Hao-Wei, and 鄭皓瑋. "Twofold Concatenated High-Rate Space-Time Block Codes." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/s3sxw4.

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碩士
國立臺北科技大學
電機工程系
106
The 5th generation mobile networks (5G) meets the requirements of high transmission rate and communication stability. The technology of 5G also provides higher spectral efficiency, wider coverage rate, and lower signal delay than those of 4G. In this thesis, we concentrate on the study of high-rate space-time block codes in the MIMO system. Multilevel coding scheme is adopted to improve the coding gain. Then, Reed-Solomon Codes are further concatenated to provide better error correcting capability. Computer simulation is performed to verify the error performance.
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33

Chow, William. "Concatenated space-time block codes and turbo codes with unstructured interference." 2004. http://hdl.handle.net/1828/452.

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The performance of space-time block codes in providing transmit diversity is severely degraded when strong localized interference is present. This problem is addressed by investigating a recently proposed coherent space-time block code decoding algorithm for unknown interference suppression. The algorithm assumes a Gaussian noise and interference approximation and is based on a cyclic-based maximum-likelihood estimation technique (CML). In this thesis, simulations are done applying CML in a coherent system with unstructured interference to validate previous work. An extension of these results is obtained by examining factors that affect CML performance and modifying CML for use in a noncoherent system. To improve bit error rate performance, a turbo code for channel coding was added to both systems. This addition required the development of reliability metrics for soft-information transfer between the space-time block code detector and the turbo code decoder. Significant coding gains exceeding 8dB at a bit error rate of are achieved for the turbo-coded system when compared to that of an uncoded system.
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34

Lee, Jia-Jhan, and 李佳展. "Design Scheme of Space-Time Block Codes Concatenated with Turbo Codes." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/65108082199099493675.

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碩士
中興大學
電機工程學系所
95
The wireless channel suffers severe attenuation caused by multipath fading. The effective technique to mitigate multipath fading is to use the time or frequency diversity. The communication system with multiple input multiple output can combat the channel attenuation by spatial diversity and increase the channel information capacity. The principle of space-time coding schemes is to combine the concept of channel coding design and multiple transmit antennas, which are then effectively applied to multipath wireless channel. Since the amount of data transfer of the modern digital or mobile communication is increasing, the reliability of the data transfer has become more and more important. Therefore, the error correction coding has played a very important role in wireless communication channel. The turbo code is one of the most popular error correction codes at present due to its good error correction ability. Besides, the turbo code is adopted in the 3G mobile communication standard. In this thesis, we present the application of several important concepts of wireless digital communications, i.e., serial concatenation, turbo coding, and temporal and antenna diversity . We combine the turbo code and the space-time block code and use the LogMAP algorithm to implement the soft in/soft out decoding algorithms of turbo code. Finally, we present our simulation results under different encoding scheme of the space time block code. Furthermore, we also present the comparison of the simulation result under different rate of space-time block codes but the same number of transmit antennas.
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35

YI, ZHIHANG. "Distributed Space-Time Block Codes in Wireless Cooperative Networks." Thesis, 2009. http://hdl.handle.net/1974/1978.

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In cooperative networks, relays cooperate and form a distributed multi-antenna system to provide spatial diversity. In order to achieve high bandwidth efficiency, distributed space-time block codes (DSTBCs) are proposed and have been studied extensively. Among all DSTBCs, this thesis focuses on the codes which are single-symbol maximum likelihood (ML) decodable and can achieve the full diversity order. This thesis presents four works on single-symbol ML decodable DSTBCs. The first work proposes the row-monomial distributed orthogonal space-time block codes (DOSTBCs). We find an upper bound of the data-rate of the row-monomial DOSTBC and construct the codes achieving this upper bound. In the second work, we first study the general DOSTBCs and derive an upper bound of the data-rate of the DOSTBC. Secondly, we propose the row-monomial DOSTBCs with channel phase information (DOSTBCs-CPI) and derive an upper bound of the data-rate of those codes. Furthermore, we find the actual row-monomial DOSTBCs-CPI which achieve the upper bound of the data-rate. In the third and fourth works of this thesis, we focus on error performance analysis of single-symbol ML decodable DSTBCs. Specifically, we study the distributed Alamouti's code in dissimilar cooperative networks. In the third work, we assume that the relays are blind relays and we derive two very accurate approximate bit error rate (BER) expressions of the distributed Alamouti's code. In the fourth work, we assume that the relays are CSI-assisted relays. When those CSI-assisted relays adopt the amplifying coefficients that was proposed in [33] and widely used in many previous publications, upper and lower bounds of the BER of the distributed Alamouti's code are derived. Very surprisingly, the lower bound indicates that the code cannot achieve the full diversity order when the CSI-assisted relays adopt the amplifying coefficients proposed in [33]. Therefore, we propose a new threshold-based amplifying coefficient and it makes the code achieve the full diversity order two. Moreover, three optimum and one suboptimum schemes are developed to calculate the threshold used in this new amplifying coefficient.
Thesis (Ph.D, Electrical & Computer Engineering) -- Queen's University, 2009-06-27 19:07:47.066
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36

Jithamithra, G. R. "Space-Time Block Codes With Low Sphere-Decoding Complexity." Thesis, 2013. https://etd.iisc.ac.in/handle/2005/2612.

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One of the most popular ways to exploit the advantages of a multiple-input multiple-output (MIMO) system is using space time block coding. A space time block code (STBC) is a finite set of complex matrices whose entries consist of the information symbols to be transmitted. A linear STBC is one in which the information symbols are linearly combined to form a two-dimensional code matrix. A well known method of maximum-likelihood (ML) decoding of such STBCs is using the sphere decoder (SD). In this thesis, new constructions of STBCs with low sphere decoding complexity are presented and various ways of characterizing and reducing the sphere decoding complexity of an STBC are addressed. The construction of low sphere decoding complexity STBCs is tackled using irreducible matrix representations of Clifford algebras, cyclic division algebras and crossed-product algebras. The complexity reduction algorithms for the STBCs constructed are explored using tree based search algorithms. Considering an STBC as a vector space over the set of weight matrices, the problem of characterizing the sphere decoding complexity is addressed using quadratic form representations. The main results are as follows. A sub-class of fast decodable STBCs known as Block Orthogonal STBCs (BOSTBCs) are explored. A set of sufficient conditions to obtain BOSTBCs are explained. How the block orthogonal structure of these codes can be exploited to reduce the SD complexity of the STBC is then explained using a depth first tree search algorithm. Bounds on the SD complexity reduction and its relationship with the block orthogonal structure are then addressed. A set of constructions to obtain BOSTBCs are presented next using Clifford unitary weight designs (CUWDs), Coordinate-interleaved orthogonal designs (CIODs), cyclic division algebras and crossed product algebras which show that a lot of codes existing in literature exhibit the block orthogonal property. Next, the dependency of the ordering of information symbols on the SD complexity is discussed following which a quadratic form representation known as the Hurwitz-Radon quadratic form (HRQF) of an STBC is presented which is solely dependent on the weight matrices of the STBC and their ordering. It is then shown that the SD complexity is only a function of the weight matrices defining the code and their ordering, and not of the channel realization (even though the equivalent channel when SD is used depends on the channel realization). It is also shown that the SD complexity is completely captured into a single matrix obtained from the HRQF. Also, for a given set of weight matrices, an algorithm to obtain a best ordering of them leading to the least SD complexity is presented using the HRQF matrix.
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37

Jithamithra, G. R. "Space-Time Block Codes With Low Sphere-Decoding Complexity." Thesis, 2013. http://etd.iisc.ernet.in/handle/2005/2612.

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One of the most popular ways to exploit the advantages of a multiple-input multiple-output (MIMO) system is using space time block coding. A space time block code (STBC) is a finite set of complex matrices whose entries consist of the information symbols to be transmitted. A linear STBC is one in which the information symbols are linearly combined to form a two-dimensional code matrix. A well known method of maximum-likelihood (ML) decoding of such STBCs is using the sphere decoder (SD). In this thesis, new constructions of STBCs with low sphere decoding complexity are presented and various ways of characterizing and reducing the sphere decoding complexity of an STBC are addressed. The construction of low sphere decoding complexity STBCs is tackled using irreducible matrix representations of Clifford algebras, cyclic division algebras and crossed-product algebras. The complexity reduction algorithms for the STBCs constructed are explored using tree based search algorithms. Considering an STBC as a vector space over the set of weight matrices, the problem of characterizing the sphere decoding complexity is addressed using quadratic form representations. The main results are as follows. A sub-class of fast decodable STBCs known as Block Orthogonal STBCs (BOSTBCs) are explored. A set of sufficient conditions to obtain BOSTBCs are explained. How the block orthogonal structure of these codes can be exploited to reduce the SD complexity of the STBC is then explained using a depth first tree search algorithm. Bounds on the SD complexity reduction and its relationship with the block orthogonal structure are then addressed. A set of constructions to obtain BOSTBCs are presented next using Clifford unitary weight designs (CUWDs), Coordinate-interleaved orthogonal designs (CIODs), cyclic division algebras and crossed product algebras which show that a lot of codes existing in literature exhibit the block orthogonal property. Next, the dependency of the ordering of information symbols on the SD complexity is discussed following which a quadratic form representation known as the Hurwitz-Radon quadratic form (HRQF) of an STBC is presented which is solely dependent on the weight matrices of the STBC and their ordering. It is then shown that the SD complexity is only a function of the weight matrices defining the code and their ordering, and not of the channel realization (even though the equivalent channel when SD is used depends on the channel realization). It is also shown that the SD complexity is completely captured into a single matrix obtained from the HRQF. Also, for a given set of weight matrices, an algorithm to obtain a best ordering of them leading to the least SD complexity is presented using the HRQF matrix.
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38

Huei-Min, Huang, and 黃暉閔. "Performance Evaluation of Space-Time Block Codes Concatenated with Turbo Codes and LDPC Codes." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/96876167066577233975.

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碩士
國立中興大學
電機工程學系所
96
The multi-input-multi-output (MINO) technique is one in the breakthroughs of wireless communications. Space time block code (STBC) with maximal ratio receive combining (MRRC) is one of the systems using MIMO to reduce error rate by increasing the numbers of antennas in transmitter and receiver. The system performance can be greatly improved by applying error correcting coding, such as turbo codes and low density party check (LDPC) codes which are known because of performance approaching their to Shannon limits. In this thesis, we first introduce the traditional MRRC with 1 transmitter antenna and multi receiver antennas. Then we describe the property of STBC with multi transmitter antennas and multi receiver antennas. For error correcting codes, we use turbo codes and LDPC codes. In turbo codes, we use two parallel concatenated convolution codes for encoding and BCJR algorithm for decoding. For LDPC codes, we use IEEE 802.16e standard for encoding and sum-product algorithm for decoding. Finally, we combine turbo codes and LDPC codes with MIMO system and discuss the bandwidth efficiency of these combinations.
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39

Tsai, Chia-Hung, and 蔡嘉紘. "BCH Coded Multilevel Space-Time Block Codes with Three Time Slots and Two Transmit Antennas." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/y94yxw.

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碩士
國立臺北科技大學
電機工程研究所
105
In digital transmission, the technical of error control coding can improve the error rate. In recent years, multiple-input multiple output (MIMO) schemes can be used to over the problem of multipath fading in wireless communication environments. In this thesis, we proposed a multilevel space-time block code with two transmit antennas and three time slots which can be applied to LTE-A frame structure. A transmission system which can achieve high transmission rate requirements in the MIMO. This new structure is designed by multilevel space-time block code and BCH code. The simulation results show that this new structure can achieve full rate transmission and outstanding error performance.
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40

Botha, P. R. (Philippus Rudolph). "Iterative decoding of space-time-frequency block coded mimo concatenated with LDPH codes." Diss., 2013. http://hdl.handle.net/2263/33344.

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In this dissertation the aim was to investigate the usage of algorithms found in computer science and apply suitable algorithms to the problem of decoding multiple-input multipleoutput (MIMO) space-time-frequency block coded signals. It was found that the sphere decoder is a specific implementation of the A* tree search algorithm that is well known in computer science. Based on this knowledge, the sphere decoder was extended to include a priori information in the maximum a posteriori probability (MAP) joint decoding of the STFC block coded MIMO signals. The added complexity the addition of a priori information has on the sphere decoder was investigated and compared to the sphere decoder without a priori information. To mitigate the potential additional complexity several algorithms that determine the order in which the symbols are decoded were investigated. Three new algorithms incorporating a priori information were developed and compared with two existing algorithms. The existing algorithms compared against are sorting based on the norms of the channel matrix columns and the sorted QR decomposition. Additionally, the zero forcing (ZF) and minimum mean squared error (MMSE) decoderswith and without decision feedback (DF) were also extended to include a priori information. The developed method of incorporating a priori information was compared to an existing algorithm based on receive vector translation (RVT). The limitation of RVT to quadrature phase shift keying (QPSK) and binary shift keying (BPSK) constellations was also shown in its derivation. The impact of the various symbol sorting algorithms initially developed for the sphere decoder on these decoders was also investigated. The developed a priori decoders operate in the log domain and as such accept a priori information in log-likelihood ratios (LLRs). In order to output LLRs to the forward error correcting (FEC) code, use of the max-log approximation, occasionally referred to as hard-to-soft decoding, was made. In order to test the developed decoders, an iterative turbo decoder structure was used together with an LDPC decoder to decode threaded algebraic space-time (TAST) codes in a Rayleigh faded MIMO channel. Two variables that have the greatest impact on the performance of the turbo decoder were identified: the hard limit value of the LLRs to the LDPC decoder and the number of independently faded bits in the LDPC code.
Dissertation (MEng)--University of Pretoria, 2013.
gm2014
Electrical, Electronic and Computer Engineering
unrestricted
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41

Sripati, U. "Space-Time-Block Codes For MIMO Fading Channels From Codes Over Finite Fields." Thesis, 2004. https://etd.iisc.ac.in/handle/2005/1195.

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Sripati, U. "Space-Time-Block Codes For MIMO Fading Channels From Codes Over Finite Fields." Thesis, 2004. http://etd.iisc.ernet.in/handle/2005/1195.

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43

"Expanded Super-Orthogonal Space-Time Block Codes with Systematic Construction." 2006. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0016-1303200709274168.

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44

Kiarashi, Nooshin. "Reliability-based Detection of Variable-rate Space-time Block Codes." Thesis, 2008. http://hdl.handle.net/1974/1490.

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We present a new sub-optimal near-maximum-likelihood (ML) detection method for the family of variable-rate space-time block codes (VRSTBC). The proposed detection method is based on the concept of symbol reliability and provides a wide range of performance-complexity trade-offs. The reliability measures are defined with the help of a recent generic ML metric expression. The error performance and complexity analysis of the method via simulations show an achievable near-ML error performance with significant reduction in complexity. The performance of the proposed method is also compared with the group interference cancellation (GIC) method which was the detection method originally applied to VRSTBCs and the results show a significant improvement. The new method offers various levels of error protection via a simple parameter and hence can provide the users of a wireless network with different performance levels according to their cost allowance. Unequal error protection by VRSTBCs under the new detection method was explored. Several applications integrating data with different levels of sensitivity to error can benefit from the wide range of possibilities that the combination of the proposed detection method and VRSTBCs provides. To further explore these flexibilities, four practically interesting power allocation schemes were applied to the transmission and the behaviors were observed through case studies.
Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2008-09-26 23:45:07.81
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45

丁元玟. "Expanded Super-Orthogonal Space-Time Block Codes with Systematic Construction." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/92681399502022704182.

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碩士
國立清華大學
通訊工程研究所
94
Space-time codes in both spatial and temporal domains have been proposed and become very popular for use in multi-input multi output systems. This thesis introduces a more general structure for super-orthogonal space-time codes called expanded super-orthogonal space time codes, which can retain the property that the maximum-likelihood decoding complexity is linear in the number of transmit antennas. Its codebook can be obtained by expanding the original space-time block code via both sides of unitary transformations. Besides, with a systematic parameterization, we can show a systematic procedure to obtain codebooks with optimal diversity gain. The results demonstrate better performance compared with super-orthogonal space-time block codes in terms of bit error rate.
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46

Tsai, Hao-Chain, and 蔡晧謙. "Single-Carrier Space-Time Block Codes with Frequency Domain Equalization." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/31548536142672938594.

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碩士
國立成功大學
電腦與通信工程研究所
94
Abstract In 2002, FCC decided to release 3.6~10.1 GHz spectrum for commercial use, and this indicates that future communication systems is of wideband and high transmission rate. However, for high data rate transmission the multipath channel results in time dispersive phenomenon and causes each symbol interfered by lots of symbols several time periods ago. For such intersymbol interference (ISI), or frequency-selective fading, the system needs complex time-domain equalization (TDE), for which the number of tap coefficients increases with the channel delay spread, and conventional time-domain equalization (TDE) may be of high complexity since the necessary number of tap coefficients increases with the channel delay spread. In this thesis, to avoid the complex time-domain equalization in the multipath channel, we first study the single-carrier block transmission with frequency-domain equalization (FDE). Similar to the orthogonal frequency-division multiplexing (OFDM) transmission, frequency-domain equalization has lower complexity than time-domain equalization. The SC block transmission also avoids the problem of high peak to average power ratio (PAPR) that occurs in OFDM transmission. We further consider SC block transmission with space time block coding (STBC), in which we study how to use permutation on the data sequences of the two antennas such that the receiver could have low-complexity data detection. Practical channel estimation based on a least square fitting (LSF) approach is also considered.
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47

Lai, Jian-Wei, and 賴建薳. "Application of Space-Time-Block-Codes to MIMO-OFDM Systems." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/68195145140011433348.

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Abstract:
碩士
輔仁大學
電機工程學系碩士班
102
The space–time-block-code (STBC) multiple-input- multiple-output (MIMO) cyclic-prefix orthogonal frequency-division multiplexing (CP-OFDM) provides a good performance for the multiuser scenario. In this thesis, the channel impulse responses of the space- time-coded MIMO CP-OFDM system are shown to be identifiable up to two ambiguity matrices by subspace channel estimation. The time domain zero-forcing equalizer (ZF)) is used to detect OFDM symbols. Based on the Circular structure of channel matrix, We propose a novel approach to largely increase the number of OFDM symbols. The proposed subspace channel estimation can converge within a small amount of OFDM symbols.
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48

Li, Yan-Cheng, and 黎彥呈. "Soft-Output Sphere Detection of Double Space-Time Block Codes." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/43077901374646431988.

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Abstract:
碩士
國立臺北大學
通訊工程研究所
101
A fast maximum-likelihood (ML) detection algorithm with low computational complexity was proposed for double space-time block codes (DSTBCs) recently. However, it only provides hard outputs. In this thesis, we extend the fast ML detection algorithm to offer soft outputs such that near-optimum performance of the DSTBC is obtained. This extension is done by using the single-tree search (STS) technique which was developed for spatial multiplexing in multiple-input multiple-output communication systems. Simulation results show that the proposed soft-output algorithm outperforms the hard-output one approximately by 3 dB while its complexity is lower than the brute-force algorithm around 61.15%.
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49

Shiao, Yat-Tai, and 蕭義泰. "An Implementation of Space Time Block Codes by Verilog HDL." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/39828380361265411230.

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Abstract:
碩士
中原大學
電機工程研究所
93
Foschini,Gans and Telatar proved that multiple input multiple output can introduce spatial diversity and increased information capacity. These results have motivated a new area in error correcting codes . The Space Time Block Codes (STBC) proposed by Tarkoh .Space-Time Coding (STC) schemes can combine the channel code design and the use of multiple transmit antennas . The Verilog language be Gateway Design Automation company build up since 1994 , Verilog language already become a standard hardware description language, Popularly use in VLSI and Digital System Design . Otherwise, Verilog language was first language can support any mix design level , At the same time provide Switch level、Logic level、Register Transfer Level and more than High-level describe. The Verilog simulation environment to provide a powerful combine environment to improve Digital Design step and test process. In our thesis, We will simply introduce Space Time Block Codes and Verilog HDL, we firstly use Matlab program to verify the correctness of our design ,After write Verilog HDL code to describe its function, Let the function can implement on chip.
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50

Natarajan, Lakshmi Prasad. "Low-Complexity Decoding and Construction of Space-Time Block Codes." Thesis, 2013. http://etd.iisc.ac.in/handle/2005/3372.

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Space-Time Block Coding is an efficient communication technique used in multiple-input multiple-output wireless systems. The complexity with which a Space-Time Block Code (STBC) can be decoded is important from an implementation point of view since it directly affects the receiver complexity and speed. In this thesis, we address the problem of designing low complexity decoding techniques for STBCs, and constructing STBCs that achieve high rate and full-diversity with these decoders. This thesis is divided into two parts; the first is concerned with the optimal decoder, viz. the maximum-likelihood (ML) decoder, and the second with non-ML decoders. An STBC is said to be multigroup ML decodable if the information symbols encoded by it can be partitioned into several groups such that each symbol group can be ML decoded independently of the others, and thereby admitting low complexity ML decoding. In this thesis, we first give a new framework for constructing low ML decoding complexity STBCs using codes over the Klein group, and show that almost all known low ML decoding complexity STBCs can be obtained by this method. Using this framework we then construct new full-diversity STBCs that have the least known ML decoding complexity for a large set of choices of number of transmit antennas and rate. We then introduce the notion of Asymptotically-Good (AG) multigroup ML decodable codes, which are families of multigroup ML decodable codes whose rate increases linearly with the number of transmit antennas. We give constructions for full-diversity AG multigroup ML decodable codes for each number of groups g > 1. For g > 2, these are the first instances of g-group ML decodable codes that are AG or have rate more than 1. For g = 2 and identical delay, the new codes match the known families of AG codes in terms of rate. In the final section of the first part we show that the upper triangular matrix R encountered during the sphere-decoding of STBCs can be rank-deficient, thus leading to higher sphere-decoding complexity, even when the rate is less than the minimum of the number of transmit antennas and the number receive antennas. We show that all known AG multigroup ML decodable codes suffer from such rank-deficiency, and we explicitly derive the sphere-decoding complexities of most known AG multigroup ML decodable codes. In the second part of this thesis we first study a low complexity non-ML decoder introduced by Guo and Xia called Partial Interference Cancellation (PIC) decoder. We give a new full-diversity criterion for PIC decoding of STBCs which is equivalent to the criterion of Guo and Xia, and is easier to check. We then show that Distributed STBCs (DSTBCs) used in wireless relay networks can be full-diversity PIC decoded, and we give a full-diversity criterion for the same. We then construct full-diversity PIC decodable STBCs and DSTBCs which give higher rate and better error performance than known multigroup ML decodable codes for similar decoding complexity, and which include other known full-diversity PIC decodable codes as special cases. Finally, inspired by a low complexity essentially-ML decoder given by Sirianunpiboon et al. for the two and three antenna Perfect codes, we introduce a new non-ML decoder called Adaptive Conditional Zero-Forcing (ACZF) decoder which includes the technique of Sirianunpiboon et al. as a special case. We give a full-diversity criterion for ACZF decoding, and show that the Perfect codes for two, three and four antennas, the Threaded Algebraic Space-Time code, and the 4 antenna rate 2 code of Srinath and Rajan satisfy this criterion. Simulation results show that the proposed decoder performs identical to ML decoding for these five codes. These STBCs along with ACZF decoding have the best error performance with least complexity among all known STBCs for four or less transmit antennas.
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