Dissertations / Theses on the topic 'Smart Antenna System'
To see the other types of publications on this topic, follow the link: Smart Antenna System.
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Smart Antenna System.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Tidd, William Graves. "Sequential beamspace smart antenna system." Thesis, Montana State University, 2011. http://etd.lib.montana.edu/etd/2011/tidd/TiddW0511.pdf.
Full textAbstract:
This thesis proposes a design of a novel and innovative sequential beamspace (SBS) smart antenna system. The system is capable of accurate direction of arrival (DOA) estimation in beamspace and efficient beamforming. Moreover, the robust functionality of such a system includes high resolution radio frequency (RF) emitter DOA estimation and beamforming in a noisy environment in the presence of strong interference. Simulations for DOA estimation using beamspace MUSIC and beamspace Capon methods are presented in conjunction with Capon beamforming. These methods are compared and contrasted with proven element space DOA estimation techniques to demonstrate the validity and advantages of pursuing a SBS smart antenna for real-world applications. The beamspace DOA estimation accuracy, resolution, beamforming pattern, and output signal quality have been thoroughly studied and quantified. The algorithms have been tailored to utilize an 8 element uniform circular array (UCA) and an 8 channel analog beamformer (BF) operating at 5.8 GHz to gather lab-based experimental results. The simulations and experimental results show that the proposed system can achieve good performance once it is properly synchronized using a time delay correction filter. In addition, a significant decrease in hardware is realized when operating in beamspace versus element space.
2
Tung, Edwin Tai-Wing. "A multiport antenna for an indoor PCS smart antenna system." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ38646.pdf.
Full text
3
Lee, Gil Young. "Conformal Body-Worn Smart Antenna System for Wideband UHF Operation." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1323756546.
Full text
4
Janapsatya, Januar. "Switched-beam smart antenna system for indoor wireless LAN /." [St. Lucia, Qld.], 2004. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18419.pdf.
Full text
5
Chakravorti, Mark F. J. "CMOS analog signal processing for a smart antenna system." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0018/MQ49671.pdf.
Full text
6
Roh, Mark C. (Mark Charles) 1975. "A base station smart antenna system for CDMA cellular." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/47613.
Full text
7
Ng, Kok Keng. "Smart antenna application in DS-CDMA mobile communication system." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2002. http://library.nps.navy.mil/uhtbin/hyperion-image/02sep%5FNg.pdf.
Full text
8
Schacht, Mirko [Verfasser]. "System Performance Gains from Smart Antenna Concepts in CDMA / Mirko Schacht." Aachen : Shaker, 2005. http://d-nb.info/1181620074/34.
Full text
9
Ng, Stewart Siew Loon. "Smart antenna in DS-CDMA mobile communication system using circular array /." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2003. http://library.nps.navy.mil/uhtbin/hyperion-image/03Mar%5FNg.pdf.
Full text
10
Yoon, Hwan-Sik. "Design, Modeling, and Optimization of a Mechanically Reconfigurable Smart Reflector Antenna System." The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1036426477.
Full text
11
Khallaayoun, Ahmed. "High resolution direction of arrival estimation analysis and implementation in a smart antenna system." Thesis, Montana State University, 2010. http://etd.lib.montana.edu/etd/2010/khallaayoun/KhallaayounA0510.pdf.
Full textAbstract:
The goal of this research is to equip the smart antenna system designed by the telecommunication group at the department of Electrical and Computer Engineering at Montana State University with high resolution direction of arrival estimation (DOA) capabilities; the DOA block should provide accurate estimates of emitters' DOAs while being computationally efficient. Intensive study on DOA estimation algorithms was carried out to pinpoint the most suitable algorithm for the application of interest, and the spectral methods were chosen for this study. The outcome of the study consisted of generating a novel algorithm, spatial selective MUSIC, which is comparable in accuracy to other high resolution algorithms but does not require the intensive computational burden that is typical of high resolution spectral methods. Spatial selective MUSIC is compared in terms of bias, resolution, robustness and computational efficiency against the most widely used DOA estimation algorithms, namely, Bartlett, Capon, MUSIC, and beamspace MUSIC. The design, troubleshooting, and implementation of the hardware needed to implement the DOA estimation in a real case scenario was achieved. Two design phases were necessary to implement the center piece of the hardware needed to achieve DOA estimation. The 5.8 GHz 8 channel receiver board along with a casing that egg crates the RF channels for channel-to-channel isolation was designed and built. A National Instrument data acquisition card was used to simultaneously sample all the 8 channels at 2.5 MSPS, the data was processed using the PC interface built in LabView. Phase calibration that accounts for the overall system magnitude and phase differences along with a novel calibration method to mitigate the effects of magnitude and phase variations along with mutual coupling was produced during this research and was imperative to achieving high resolution DOA estimation in the lab. The DOA estimation capabilities of the built system was tested within the overall smart antenna system and showed promising results. The overall performance enhancement that the DOA estimation block can provide cannot however be fully realized until the beamforming block is revised to provide accurate and deep null placing along with a narrower beam width. This cannot be achieved with the current system due to limitations in the number of the array elements used and the granularity in the phase shifters and attenuators used in the analog beamformer.
12
Choi, Junsung. "Latency Study and System Design Guidelines for Cooperative LTE-DSRC Vehicle-to-Everything (V2X) Communications including Smart Antenna." Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/78083.
Full textAbstract:
Vehicle-related communications are a key application to be enabled by Fifth Generation (5G) wireless systems. The communications enabled by the future Internet of Vehicles (IoV) that are connected to every wireless device are referred to as Vehicle-to-Everything (V2X) communications. A major application of V2X communication systems will be to provide emergency warnings. This thesis evaluates Long-Term Evolution (LTE) and Dedicated Short Range Communications (DSRC) in terms of service quality and latency, and provides guidelines for design of cooperative LTE-DSRC systems for V2X communications. An extensive simulation analysis shows that (1) the number of users in need of warning has an effect on latency, and more so for LTE than for DSRC, (2) the DSRC priority parameter has an impact on the latency, and (3) wider system bandwidths and smaller cell sizes reduce latency for LTE. The end-to-end latency of LTE can be as high as 1.3 s, whereas the DSRC latency is below 15 ms for up to 250 users.
Also, improving performance of systems is as much as important as studying about latency. One method to improving performance is using a better suitable antenna for physical communication. The mobility of vehicles results in a highly variable propagation channel that complicates communication. Use of a smart, steerable antenna can be one solution. The most commonly used antennas for vehicular communication are omnidirectional. Such antennas have consistent performance over all angles in the horizontal plane; however, rapidly steerable directional antennas should perform better in a dynamic propagation environment. A linear array antenna can perform dynamical appropriate azimuth pattern by having different weights of each element. The later section includes (1) identifying beam pattern parameters based on locations of a vehicular transmitter and fixed receivers and (2) an approach to find weights of each element of linear array antenna. Through the simulations with our approach and realistic scenarios, the desired array pattern can be achieved and array element weights can be calculated for the desired beam pattern. Based on the simulation results, DSRC is preferred to use in the scenario which contains large number of users with setup of higher priority, and LTE is preferred to use with wider bandwidth and smaller cell size. Also, the approach to find the controllable array antenna can be developed to the actual implementation of hardware with USRP.Master of Science
13
Panique, Michael David. "Design and evaluation of test bed software for a smart antenna system supporting wireless communication in rural areas." Thesis, Montana State University, 2008. http://etd.lib.montana.edu/etd/2008/panique/PaniqueM0508.pdf.
Full textAbstract:
This paper explores the design and development of a test bed to analyze feasibility of utilizing adaptive smart antennas in conjunction with high bandwidth WiMAX radio systems to achieve improved performance for mobile nodes and to suppress potential interference from unwanted signals. Although the new WiMAX standard offers the potential for using smart, adaptive antennas, this functionality has not been implemented. This design serves as a common platform for testing adaptive array algorithms including direction of arrival (DOA) estimation, beamforming, and adaptive tracking, as well as complete wireless communication with a WiMAX radio. Heavy emphasis will be placed on ease of implementation in a multi-channel / multi-user environment. Detailed here, is the design and development of an 8-channel adaptive smart antenna test bed for WiMAX radio systems. The test bed consists of an 8-element circular antenna array, a PC running a software interface, and RF receiver and transmission boards which enable DOA estimation and beamforming to take place. We have developed a LabVIEW interface for a PC controlled smart antenna test bed supporting two mobile targets. The main system has three components, DOA estimation and signal validation, beamforming (null steering or multi-beam), and target tracking. The interface is implemented in a modular fashion so that a maximum amount of flexibility is available to test bed users. The test bed was used in conjunction with MATLAB simulations to analyze DOA estimation, beamforming, and nullsteering algorithms necessary to realize a smart antenna system capable of handling multiple users and suppressing nearby strong interference. The results of tests run using the test bed showed that communication delay and hardware limitations on the RF transmission board were a limiting factor in the performance of the smart antenna system.
14
Hwang, Seung-Hyeon. "Adaptive antenna techniques for smart antennas and radar systems." Related electronic resource: Current Research at SU : database of SU dissertations, recent titles available full text, 2005. http://wwwlib.umi.com/cr/syr/main.
Full text
15
Dorni, Aljoša. "IEEE 802.11 Networks: MAC Protocols for Heterogeneous Multi-Antenna Scenarios and Software-Defined Radio PHY Layer Implementation." Doctoral thesis, Università degli studi di Trieste, 2013. http://hdl.handle.net/10077/8538.
Full textAbstract:
2011/2012The objective of this thesis is to discuss the performance achieved by IEEE 802.11 networks, considering in detail their simulation and experimental analysis, as well as the implementation aspects. The original contribution of this dissertation involves three main research fields within the context of distributed wireless networks: the experimental and theoretical analysis of IEEE 802.11e networks in presence of quality of service mechanisms, the development and the simulation of backward compatible medium access control protocols in presence of smart antenna systems, and, finally, the implementation of the IEEE 802.11ag physical layer on software-defined radio platforms.
L’obiettivo di questa tesi è discutere le prestazioni ottenibili nelle reti IEEE 802.11, prendendo in considerazione sia la loro simulazione ed analisi sperimentale, sia gli aspetti implementativi. Il contributo originale di questa tesi include tre argomenti principali che riguardano le reti wireless distribuite: l’analisi sperimentale e teorica delle reti 802.11e che adottano meccanismi di qualità del servizio, lo sviluppo e la simulazione di schemi di accesso multiplo retrocompatibili basati sull’utilizzo di sistemi di antenne intelligenti, e, infine, l’implementazione su piattaforme software-defined radio del livello fisico 802.11ag.
XXV Ciclo
1980
16
Palantei, Elyas. "Switched Parasitic Smart Antenna: Design and Implementation for Wireless Communication Systems." Thesis, Griffith University, 2012. http://hdl.handle.net/10072/366219.
Full textAbstract:
Smart antenna technology in applications such as the next-G wireless communication networks may improve the quality of service (QoS). One category of smart antennas is the switched beam smart antenna (SBA). These antennas can be grouped into plug and play antennas and adaptive internal antennas. Four types of switched beam smart antennas were investigated including a six monopole array on circular ground plane with conducting sleeve, five monopoles on a circular ground plane without a conducting sleeve, a reconfigurable monopole on a cylindrical hollow ground structure, and a reconfigurable adaptive internal antenna. The first two antennas were constructed with a switched parasitic array of elements combined with an RF circuit with microcontroller. Two of the four antenna prototypes were capable for steering the beam pattern automatically based on signal strength (RSSI) or bit error rate (BER) scanning. The two remaining antennas were designed for electronic beamforming and electronic frequency tuning. Both numerical and empirical investigations were undertaken to measure performance and investigate manufacture difficulties. The numerical investigations were undertaken using both the method of moment (MoM)-NEC and the finite element method (FEM)-HFSS modeling. The fabrication and testing in an anechoic chamber were used to explore the actual performance of the designed antennas. The fabrication of the last two types of antennas was not implemented. Further work is required to find the optimal design for all antennas investigated. This study suggests significant promise for these antennas in wireless networks.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Engineering
Science, Environment, Engineering and Technology
Full Text
17
OLIVEIRA, Elias Marques Ferreira De. "Desenvolvimento de sistema inteligente de controle de arranjo de antenas para aplicação no sistema Celpe." Univesidade Federal de Pernambuco, 2016. https://repositorio.ufpe.br/handle/123456789/18271.
Full textAbstract:
Submitted by Irene Nascimento (irene.kessia@ufpe.br) on 2017-01-30T18:03:51Z
No. of bitstreams: 2
license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5)
Dissertação - Elias Marques V4.2 (Revisão Biblioteca).pdf: 4899848 bytes, checksum: 78834b022de3c1d5eb7fcee1273f65c7 (MD5)Made available in DSpace on 2017-01-30T18:03:51Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação - Elias Marques V4.2 (Revisão Biblioteca).pdf: 4899848 bytes, checksum: 78834b022de3c1d5eb7fcee1273f65c7 (MD5) Previous issue date: 2016-02-22
FACEPE
Este trabalho de dissertação apresenta a concepção e implantação de um sistema controlador de arranjo de antenas capaz de integrar-se a uma rede de comunicação SCADA e direcionar o diagrama de radiação de um arranjo de antenas, garantindo melhor comunicação entre estação base e remota. É apresentado um circuito de RF capaz de realizar o controle automático das fases de alimentação de um arranjo de antenas composto por diversos dispositivos de RF, incluindo um defasador de 8 bits. São apresentados testes destes dispositivos bem como a caracterização de ramos constituídos por estes componentes. Desenvolveu-se também um circuito controlador de arranjo de antenas que desempenha funções de identificação de endereços e determina as fases a serem utilizadas no controle dos defasadores. O circuito foi testado em um projeto piloto no campus da UFPE e está instalado na subestação da CELPE na cidade de Gravatá, no interior do estado de Pernambuco.
This dissertation presents the design and implementation of a Antenna Array Controller System capable of integrating into a SCADA network and directing the main radiation lobe, granting best communication between base and remote stations. An RF circuit is presented capable of automatically controlling the phases fed to the antenna array composed by several RF devices, including an 8-bit phase shifter. Tests of the devices and the characterization of braches composed by them are shown. In addition, an antenna array controller has been developed to perform functions that include the identification of an address and the determination of the phase to be used in the phase shifters’ control. The circuit was tested in a pilot project at the UFPE campus and is installed at a CELPE substation in the city of Gravatá.
18
Elfarawi, Shaaban M. "Indoor CDMA capacity using smart antenna base station." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0019/MQ54885.pdf.
Full text
19
Yu, Xiaoming. "Multibeam smart antenna systems for wireless communications." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0034/NQ66298.pdf.
Full text
20
Zhou, Wei. "Autonomous smart antenna systems for future mobile devices." Thesis, University of Edinburgh, 2015. http://hdl.handle.net/1842/9959.
Full textAbstract:
Along with the current trend of wireless technology innovation, wideband, compact size, low-profile, lightweight and multiple functional antenna and array designs are becoming more attractive in many applications. Conventional wireless systems utilise omni-directional or sectored antenna systems. The disadvantage of such antenna systems is that the electromagnetic energy, required by a particular user located in a certain direction, is radiated unnecessarily in every direction within the entire cell, hence causing interference to other users in the system. In order to limit this source of interference and direct the energy to the desired user, smart antenna systems have been investigated and developed. This thesis presents the design, simulation, fabrication and full implementation of a novel smart antenna system for future mobile applications. The design and characterisation of a novel antenna structure and four-element liner array geometry for smart antenna systems are proposed in the first stage of this study. Firstly, a miniaturised microstrip-fed planar monopole antenna with Archimedean spiral slots to cover WiFi/Bluetooth and LTE mobile applications has been demonstrated. The fundamental structure of the proposed antenna element is a circular patch, which operates in high frequency range, for the purpose of miniaturising the circuit dimension. In order to achieve a multi-band performance, Archimedean spiral slots, acting as resonance paths, have been etched on the circular patch antenna. Different shapes of Archimedean spiral slots have been investigated and compared. The miniaturised and optimised antenna achieves a bandwidth of 2.2GHz to 2.9GHz covering WiFi/Bluetooth (2.45GHz) and LTE (2.6GHz) mobile standards. Then a four-element linear antenna array geometry utilising the planar monopole elements with Archimedean spiral slots has been described. All the relevant parameters have been studied and evaluated. Different phase shifts are excited for the array elements, and the main beam scanning range has been simulated and analysed. The second stage of the study presents several feeding network structures, which control the amplitude and phase excitations of the smart antenna elements. Research begins with the basic Wilkinson power divider configuration. Then this thesis presents a compact feeding network for circular antenna array, reconfigurable feeding networks for tuning the operating frequency and polarisations, a feeding network on high resistivity silicon (HRS), and an ultrawide-band (UWB) feeding network covering from 0.5GHz to 10GHz. The UWB feeding network is used to establish the smart antenna array system. Different topologies of phase shifters are discussed in the third stage, including ferrite phase shifters and planar phase shifters using switched delay line and loaded transmission line technologies. Diodes, FETs, MMIC and MEMS are integrated into different configurations. Based on the comparison, a low loss and high accurate Hittite MMIC analogue phase shifter has been selected and fully evaluated for this implementation. For the purpose of impedance matching and field matching, compact and ultra wideband CPW-to-Microstrip transitions are utilised between the phase shifters, feeding network and antenna elements. Finally, the fully integrated smart antenna array achieves a 10dB reflection coefficient from 2.25GHz to 2.8GHz, which covers WiFi/Bluetooth (2.45GHz) and LTE (2.6GHz) mobile applications. By appropriately controlling the voltage on the phase shifters, the main beam of the antenna array is steered ±50° and ±52°, for 2.45GHz and 2.6GHz, respectively. Furthermore, the smart antenna array demonstrates a gain of 8.5dBi with 40° 3dB bandwidth in broadside direction, and has more than 10dB side lobe level suppression across the scan. The final stage of the study investigates hardware and software automatic control systems for the smart antenna array. Two microcontrollers PIC18F4550 and LPC1768 are utilised to build the control PCBs. Using the graphical user interfaces provided in this thesis, it is able to configure the beam steering of the smart antenna array, which allows the user to analyse and optimise the signal strength of the received WiFi signals around the mobile device. The design strategies proposed in this thesis contribute to the realisation of adaptable and autonomous smart phone systems.
21
Haghdad, Mehdi, and Kamilo Feher. "PSEUDO ERROR DETECTION IN SMART ANTENNA/DIVERSITY SYSTEMS." International Foundation for Telemetering, 2003. http://hdl.handle.net/10150/605363.
Full textAbstract:
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, NevadaAn implementation of a Pseudo Error Detection (PSED) system is presented and its performance in conjunction with smart antenna and smart diversity systems tested and evaluated. Non redundancy, instant response and relative simplicity make the Pseudo Error Detectors excellent real time error monitoring systems in smart antenna and smart diversity systems. Because of the Non-redundant Error Detection mechanism in Pseudo Error Detectors, we can monitor the error quality without any coding or overhead. The output of the pseudo error detector in AWGN, selective fading Doppler shift and other interference environments is directly correlated to the BER and BLER. This direct correlation makes it a great tool for online error monitoring of a system and can have numerous applications In a PSED the Eye diagram from the demodulator is sampled once per symbol. By monitoring and comparison of the eye at sampled intervals at different thresholds, we would know if an error has occurred. By integrating this result over a period of time we can get the averaged error level. The results provided in this paper were obtained and verified by both MatLab simulations using dynamic simulation techniques and hardware measurements over dynamic channels.
22
Lei, Yu. "Resource Management with Smart Antenna in CDMA Systems." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/30876.
Full textAbstract:
Third generation (3G) mobile communication systems will provide services
supporting high-speed data network and multimedia applications in addition to voice
applications. The Smart antenna technique is one of the leading technologies that helps to
meet the requirement by such services to radio network capacity. Resource management
schemes such as power control, handoff and channel reservation/assignment are also
essential for providing the seamless services with high quality. Smart antenna techniques
will help to enhance the capability of resource management through more efficient and
flexible use of resources. In this thesis, adaptive array and switched beam antenna
techniques are compared in terms of algorithm, performance, complexity and hardware
requirements. Based on these comparisons, sub-optimal code gate algorithm are most
likely the suitable algorithms for next generation code division multiple access (CDMA)
systems due to its good performances, robustness, and low complexity. A multi-cell
CDMA simulator is developed for investigating the gain from smart antenna techniques
in both bit error rate (BER) performance improvement and enhancement to resource
management schemes. Our study shows that smart antenna techniques can significantly
improve the performance of the system and help to build more powerful and flexible
resource management schemes. With eight array elements, the system capacity can be
increased by a factor of four. Power control command rates can be reduced through the
tradeoff with the interference reduction by smart antennas. Smart antennas will also
reduce handover failure rates and further increase the system capacity by reducing the
resources reserved for soft handover.Master of Science
23
Chim, Kwok Chi. "Investigating the impact of smart antenna on SAR /." View Abstract or Full-Text, 2002. http://library.ust.hk/cgi/db/thesis.pl?ELEC%202002%20CHIM.
Full textAbstract:
Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2002.Includes bibliographical references (leaves 53-54). Also available in electronic version. Access restricted to campus users.
24
Puska, H. (Henri). "Code acquisition in direct sequence spread spectrum systems using smart antennas." Doctoral thesis, University of Oulu, 2009. http://urn.fi/urn:isbn:9789514290497.
Full textAbstract:
Abstract In this doctoral thesis, initial code synchronization (i.e., code acquisition) of a direct sequence spread spectrum (DS/SS) system is studied when a smart antenna is used in a receiver. Code synchronization means time synchronization of the used spreading code in the receiver. After an introduction to the topic, a literature review of code acquisition is presented. In addition, a review of the results in the literature under fading, data modulation, Doppler, intentional interference, multiple-access interference, other system interference, and multiple antennas is given. After that, an overview of the smart antennas, especially focusing on digital beamforming and direction-of-arrival (DOA) estimation algorithms is presented. The end part of the thesis concentrates on the author’s own research of the topic. Original articles of this article dissertation have been classified according to their contents into two groups. The first group covers DS/SS code acquisition performance in intentional interference by exploiting how well different beamforming algorithms can eliminate narrowband and wideband interfering signals in the case, where the DOA of the desired signal is known. The obtained results show that most spatial beamforming algorithms are capable of cancelling multiple different types of interfering signals if they are not arriving from the same direction as the desired signal. If angle separation between desired and interfering signals is not sufficient, then more complex methods have to be used. The second group of articles focuses on a theoretical analysis of synchronization probabilities and mean acquisition times. If the DOA of the desired signal is unknown, the whole angular uncertainty region can be divided into small angular cells using beamforming techniques, as is proposed in the literature. Then there is a two-dimensional (delay-angle) acquisition problem. In this thesis, the research work of that area is expanded to cover also advanced beamforming techniques, since they offer increased interference suppression capability. It is shown that the code acquisition performance of the delay-angle method can be improved in some cases by adding a DOA estimator into the system, because it may reduce the number of required angular cells. In addition, such a minimum mean square error (MMSE) beamforming structure is proposed, where only one period of the known pseudo noise spreading code is used as a reference signal. The method was shown to have better acquisition performance than the delay-angle method has, since MMSE beamforming does not need DOA information. However, in this thesis, such a method was not found which outperforms the rest of the methods in all scenariosTiivistelmä Tässä väitöstyössä tutkitaan suorahajotushajaspektrijärjestelmän (DS/SS, direct sequence spread spectrum) koodisynkronoinnin etsintävaihetta, kun vastaanottimessa käytetään älyantennia. Koodisynkronoinnilla tarkoitetaan järjestelmän käyttämän hajotuskoodin ajastuksen synkronointia vastaanottimessa. Johdannon jälkeen esitetään kirjallisuuskatsaus koodisynkronointiin sekä tuodaan esille kirjallisuudesta löytyviä tutkimustuloksia aihepiiristä seuraavissa tilanteissa: häipyvä kanava, Doppler-ilmiö, tahallinen häirintä, monikäyttöhäiriö, muiden järjestelmien aiheuttama häiriö sekä moniantennijärjestelmät. Tämän jälkeen esitetään yleiskatsaus älyantenneihin kohdistuen erityisesti digitaalisiin keilanmuodostus- sekä suuntaestimointialgoritmeihin. Työn loppuosa keskittyy kirjoittajan omaan tutkimukseen aiheesta. Tämän nippuväitöskirjan alkuperäiset artikkelit on luokiteltu kahteen ryhmään niiden sisältöön perustuen. Ensimmäinen ryhmä käsittelee DS/SS-järjestelmän koodisynkronoinnin etsintävaiheen suorituskykyä tahallisessa häirinnässä tutkimalla, miten hyvin erilaiset keilanmuodostusalgoritmit kykenevät poistamaan kapea- ja leveäkaistaisia häirintäsignaaleja tilanteessa, jossa hyötysignaalin tulosuunta tiedetään. Tutkimustulokset osoittavat, että monet tilatason keilanmuodostusalgoritmit kykenevät poistamaan useita erityyppisiä häirintäsignaaleita, jos ne eivät saavu hyötysignaalin kanssa samasta suunnasta. Mikäli kulmaero hyöty- ja häirintäsignaalien välillä ei ole riittävä, joudutaan käyttämään rakenteeltaan monimutkaisempia menetelmiä. Toinen ryhmä artikkeleita keskittyy synkronointiin liittyvien todennäköisyyksien ja keskimääräisen etsintäajan teoreettiseen analyysiin. Jos hyötysignaalin tulosuunta on tuntematon, voidaan kulmaepävarmuusalue jakaa pieniin kulmasoluihin käyttäen keilanmuodostustekniikoita, kuten kirjallisuudessa esitetään. Tällöin kyseessä on kaksiulotteinen (viive-kulma) etsintäongelma. Tässä työssä kyseistä tutkimusaihetta laajennetaan koskemaan myös edistyneet keilanmuodostusmenetelmät, koska ne tarjoavat parantuneen häiriönvaimennuskyvyn. Työssä osoitetaan, että viive-kulma menetelmän suorituskykyä voidaan parantaa joissakin tilanteissa lisäämällä järjestelmään suuntaestimaattori, koska se saattaa vähentää tarvittavien kulmasolujen lukumäärää. Lisäksi tutkitaan sellaista pienimmän keskineliövirheen (MMSE, minimum mean square error) keilanmuodostusmenetelmää, jossa ainoastaan yhtä hajotuskoodin koodijaksoa käytetään opetukseen. Kyseisellä menetelmällä todettiin olevan parempi suorituskyky kuin viive-kulma etsinnällä, koska MMSE-menetelmä ei tarvitse suuntainformaatiota. Tässä työssä ei kuitenkaan löydetty yhtä sellaista menetelmää, jonka suorituskyky on muita parempi kaikissa tilanteissa
25
Lakshmanan, Sriram. "Securing wireless networks against eavesdropping using smart antennas." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/26698.
Full textAbstract:
Thesis (M. S.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2008.Committee Chair: Raghupathy, Sivakumar; Committee Member: Farmarz Fekri; Committee Member: Mary Ann, Ingram. Part of the SMARTech Electronic Thesis and Dissertation Collection.
26
Kavak, Adnan. "Vector propagation channel studies for smart antenna wireless communication systems /." Full text (PDF) from UMI/Dissertation Abstracts International, 2000. http://wwwlib.umi.com/cr/utexas/fullcit?p3004302.
Full text
27
Noordin, Nurul Hazlina. "Adaptive array antenna design for wireless communication systems." Thesis, University of Edinburgh, 2013. http://hdl.handle.net/1842/8950.
Full textAbstract:
Adaptive array antennas use has been limited to non-commercial applications due to their high cost and hardware complexity. The implementation cost of adaptive array antennas can be kept to a minimum by using cost effective antennas, reducing the number of elements in the array and implementing efficient beamforming techniques. This thesis presents techniques for the design of adaptive array antennas which will enable their cost effective implementation in wireless communication systems. The techniques are investigated from three perspectives, namely, reconfigurable antenna design, wide scan array design and single-port beamforming technique. A novel single-feed polarisation reconfigurable antenna design is proposed in the first stage of this study. Different polarisation states, namely, linear polarisation (LP), left-hand circular polarisation (LHCP) and right-hand circular polarisation (RHCP), are achieved by perturbing the shape of the main radiating structure of the antenna. The proposed antenna exhibits good axial ratio (< 3 dB at 2.4 GHz) and has high radiation efficiency in both polarisation modes (91.5 % - LHCP and 86.9 % - RHCP). With a compact single feeding structure, the antenna is suitable for implementation in wireless communication devices. The second stage of the study presents the design procedure of wide scan adaptive array antennas with reduced number of elements. Adaptive array antennas with limited number of elements have limited scanning range, reduced angular scanning resolution and high sidelobe levels. To date, design synthesis of adaptive array antennas has been targeted on arrays with a large number of elements. This thesis presents a comprehensive analysis of adaptive array antennas with less than 10 elements. Different array configurations are analysed and various array design parameters such as number of elements, separation between elements and orientation of the elements are analysed in terms of their 3 dB scan range. The proposed array, the 3-faceted array, achieves a scanning range up to ±70°, which is higher than ±56° obtained from the Uniform Linear Array. The faceted arrays are then evaluated in the context of adaptive beamforming properties. It was shown that the 3-faceted array is suitable for adaptive array applications in wireless communication systems as it achieves the highest directivity compared to other faceted structures. The 3-faceted array is then synthesised for low sidelobe level. Phase correction together with amplitude tapering technique is applied to the 3-faceted array. The use of conventional and tuneable windowing techniques on the 3- faceted array is also analysed. The final stage of the study investigates beamforming techniques for the adaptive array antenna. In the first part, beamforming algorithms using different performance criteria, which include maximum signal-to noise-ratio (SINR), minimum (mean-square Error) MSE and power minimisation, are evaluated. In the second part, single-port beamforming techniques are explored. In previous single-port beamforming methods, the spatial information of the signals is not fully recovered and this limits the use of conventional adaptive beamforming algorithms. In this thesis, a novel signal estimation technique using pseudo-inverse function for single-port beamforming is proposed. The proposed polarisation reconfigurable antenna, the 3-faceted array antenna and the single-port beamforming technique achieve the required performance, which suggests the potential of adaptive array antennas to be deployed commercially, especially in wireless communication industry.
28
Durrani, Salman. "Investigations into smart antennas for CDMA wireless systems /." [St. Lucia, Qld.], 2004. http://adt.library.uq.edu.au/public/adt-QU20041201.165143/index.html.
Full text
29
Hu, Bin. "Multicarrier DS-CDMA communication systems using smart antennas." Thesis, University of Southampton, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.430726.
Full text
30
Marikar, Shakheela H. "Resource Management In 3G Systems Employing Smart Antennas." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/30875.
Full textAbstract:
Modern mobile communication systems will provide enhanced high-speed data, multimedia, and voice services to mobile users. The integration of such heterogeneous traffic types implies that the network must provide differentiated Quality of Service (QoS). Beam forming techniques have been proposed to increase the spectral efficiency of the wireless channel. Using beamforming in the network will lead to intra-cell handoffs within the cell due to user mobility. In a commercially deployed next generation cellular system, it is likely that beam forming and QoS guarantees to the users will co-exist. In this work we propose a resource allocation and management scheme tailored for a network that employs smart antennas in support of a heterogeneous user mix.
Resource management in a wireless system should take care of channel impairments and non-ideal antenna patterns. Mobile users moving from one beam to the other give rise to resource reallocation issues. Depending on the scatterer distribution in the cell, the Angle of Arrival (AoA) of the users will also change, affecting the interference pattern in the cell. In a system with data and multimedia users, some of the users are likely to be elastic in their demands for bandwidth. In this work, we propose a resource allocation and management scheme tailored for systems with smart antennas having heterogeneous users. The algorithm works by comparing the received power in the beams. Elasticity of user requirement for data services is exploited to provide adaptive QoS, thereby reducing the call dropping probability due to user mobility.
Simulation results showing the channel and Multiple Access Interference (MAI) effects on system performance are presented. The effect of channel coding to provide Bit Error Rate (BER) guarantees is studied. We also show the throughput advantage obtained using the resource management algorithms. It is also seen that the throughput of the system increases for a user population having a higher elasticity. A modified resource allocation algorithm to reduce the blocking probability of the calls is presented and performance verified using simulation. The probability of call dropping in an unmanaged system due to user mobility is shown. Our studies show that using managed system the call drop probability can be minimized.Master of Science
31
Torlak, Murat. "Estimation and capacity of channels in smart antenna wireless communication systems /." Digital version accessible at:, 1999. http://wwwlib.umi.com/cr/utexas/main.
Full text
32
Abusultan, Monther Younis. "Digital implementation of direction-of-arrival estimation techniques for smart antenna systems." Thesis, Montana State University, 2010. http://etd.lib.montana.edu/etd/2010/abusultan/AbusultanM0510.pdf.
Full textAbstract:
Adaptive antenna arrays use multiple antenna elements to form directional patterns in order to improve the performance of wireless communication systems. The antenna arrays also have the ability to detect the direction of incoming signals. These two capabilities allow a smart antenna system to adaptively beamform to more efficiently communicate between nodes. The direction-of-arrival estimation is a crucial component of the smart antenna system that uses open-loop adaptive approach. Historically this estimation has been accomplished using a personal computer. Implementing the estimation in the digital domain has the potential to provide a low cost and light weight solution due to recent advances in digital integrated circuit fabrication processes. Furthermore, digital circuitry allows for more sophisticated estimation algorithms to be implemented using the computational power of modern digital devices. This thesis presents the design and prototyping of direction-of-arrival (DOA) estimation for a smart antenna system implemented on a reconfigurable digital hardware fabric. Two DOA estimation algorithms are implemented and the performance tradeoffs between a custom hardware approach and a microprocessor-based system are compared. The algorithms were implemented for a 5.8 GHz, 8-element circular antenna array and their functionality was verified using a testbed platform. The implementation and analysis presented in this work will aid system designers to understand the tradeoffs between implementing algorithms in custom hardware versus an embedded system and when a hybrid approach is more advantageous.
33
Yiu, Candy. "High Speed Wireless Networking for 60GHz." PDXScholar, 2011. https://pdxscholar.library.pdx.edu/open_access_etds/373.
Full textAbstract:
This thesis examines the problem of providing high data-rate wireless connectivity to users in indoor environments. The goal is to be able to reach Gbps/user rates even when there are multiple users present. The technology that we study is to use the 60 GHz spectrum whose special propagation properties make it ideally suited to this task. The approaches developed include using multiple spatially distributed smart antennas in a room or multiple co-located antennas to provide coverage where needed and when needed. All the antennas are connected to a single access point which allows us to dynamically change spectrum and link allocation among the users (as they move or as their needs change). The innovations in this work include the exploitation of the special properties of 60 GHz and the corresponding design of algorithms for efficient spectrum allocation. We use detailed simulations to demonstrate that very high data rates are indeed achievable.
34
Stridh, Rickard. "Smart Antennas in Wireless Networks : Systems Issues and Performance Limits." Doctoral thesis, KTH, Signals, Sensors and Systems, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3467.
Full textAbstract:
This work deals with performance limits when using smartantennas in future wireless systems. The current evolution inthe field of wireless communication implicates a substantiallyincreased demand on transport capacity. Smart antennas is onevery powerful means to fulfill these demands. In this work theuse of smart antennas, deployed at either the access point orboth the access point and the mobile terminal isinvestigated.
In order to find out how the evolution within wirelesscommunication will continue during the ten years to come, ascenario analysis is performed where driving forces areidentified and scenarios are created.
The system aspects of uplink and downlink communicationsutilizing smart antenna algorithms are investigated. For theuplink case, the impact of different smart antenna algorithmson a packet switched radio interface is investigated. In thedownlink case, the use of joint optimal beamforming and powercontrol is examined and compared to suboptimal downlinkalgorithms. Further, an algorithm for admission control isintroduced and evaluated and the issue of optimal access pointassignment is assessed.
The extension to use smart antennas with both multipletransmitters and multiple receivers, i.e. dual arrays, canprovide high link capacity in future wireless systems. Ananalysis of indoor environment channel measurements in the 5.8GHz band is performed and the possible increase in linkcapacity is examined. It is found that in the measured indoorenvironment, the scattering is sufficiently rich to providesubstantial link capacity increase and that moderateintra-antenna-element distances is enough to give this capacityincrease.
It is concluded that smart antennas promise substantialcapacity increase and remains a strong enabling technology forfuture systems for wireless communication
35
Soodmand, Soheyl. "Optimised inductively coupled reader antennas for smart HF RFID systems." Thesis, University of Surrey, 2015. http://epubs.surrey.ac.uk/807246/.
Full textAbstract:
The Internet of things (IoT) refers to uniquely identifiable objects and their virtual representations in an Internet-like structure to be managed and inventoried by computers. Radio-frequency identification (RFID) - a prerequisite for the IoT - is an automatic way for data transaction in object identification and is used to improve automation, inventory control and checkout operations. An RFID system consists of a reader device and one or several tags. Smart reader systems are building blocks for cutting edge applications of RFID and as a subdivision of these systems, RFID smart shelf solutions are started to be implemented for large-scale item-level management where characteristics of reader antennas are critical issue. This work focuses on designing optimised reader antennas for high frequency (HF) RFID smart shelf systems which operate based on inductive coupling between the tag and the reader antennas and have good performance in crowded environments. Firstly, an approach is presented to increase band-width of HF RFID reader antennas to improve the reception of sub-carrier frequencies. A fabricated enhanced band-width antenna at 13.56 MHz is evaluated for its capability in being used for smart shelf applications. The obtained band-width supports sub-carrier frequencies for all the HF RFID standards to be detected easier and thus leads to increased identification range. It is shown the HF RFID technology is capable of identifying the distance of tagged books based on the received magnetic field intensity. Secondly, multi turn small self resonant coil (MT SSRC) antennas are introduced and analysed as a new model of inductively coupled reader antennas. Based on the analysis, two turn planar SSRC (TTP SSRC) antennas having similar dimension with the current HF RFID reader antennas are investigated. Fabricated TTP SSRC antenna operating at 13.56 MHz is resulted to optimised Q factor and more uniform near field pattern in comparison with the similar antennas. Also, a number of TTP SSRC antennas operating at a distinct frequency, 13.56MHz, are fabricated on different substrates and it is shown the desired Q factor and antenna dimension can be obtained based on the dielectric characteristics of the substrate.
36
Huang, Fei, and 黄菲. "Design and analysis of transmission protocols in wireless networks with smart antennas." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B46421610.
Full text
37
Kim, Sang-youb. "A fast estimation algorithm of array response vector for adaptive smart antenna systems /." Digital version accessible at:, 2000. http://wwwlib.umi.com/cr/utexas/main.
Full text
38
Kongara, Gopichand V. R. "Performance of a smart base station antenna in IS-136 cellular systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0004/MQ36710.pdf.
Full text
39
Tang, Hongyan. "Non-mechanical phase shifting techniques for semi-smart mobile basestation antenna systems." Thesis, Queen Mary, University of London, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.498269.
Full text
40
Alam, Fakhrul. "Space Time Processing for Third Generation CDMA Systems." Diss., Virginia Tech, 2002. http://hdl.handle.net/10919/29669.
Full textAbstract:
The capacity of a cellular system is limited by two different phenomena, namely multipath fading and multiple access interference (MAI). A Two Dimensional (2-D) receiver combats both of these by processing the signal both in the spatial and temporal domain. An ideal 2-D receiver would perform joint space-time processing, but at the price of high computational complexity. In this dissertation we investigate computationally simpler technique termed as a Beamformer-Rake. In a Beamformer-Rake, the output of a beamformer is fed into a succeeding temporal processor to take advantage of both the beamformer and Rake receiver. Wireless service providers throughout the world are working to introduce the third generation (3G) cellular service that will provide higher data rates and better spectral efficiency. Wideband CDMA (WCDMA) has been widely accepted as one of the air interfaces for 3G. A Beamformer-Rake receiver can be an effective solution to provide the receivers enhanced capabilities needed to achieve the required performance of a WCDMA system. This dissertation investigates different Beamformer-Rake receiver structures suitable for the WCDMA system and compares their performance under different operating conditions. This work develops Beamformer-Rake receivers for WCDMA uplink that employ Eigen-Beamforming techniques based on the Maximum Signal to Noise Ratio (MSNR) and Maximum Signal to Interference and Noise Ratio (MSINR) criteria. Both the structures employ Maximal Ratio Combining (MRC) to exploit temporal diversity.
MSNR based Eigen-Beamforming leads to a Simple Eigenvalue problem (SE). This work investigates several algorithms that can be employed to solve the SE and compare the algorithms in terms of their computational complexity and their performance. MSINR based Eigen-Beamforming results in a Generalized Eigenvalue problem (GE). The dissertation describes several techniques to form the GE and algorithms to solve it. We propose a new low-complexity algorithm, termed as the Adaptive Matrix Inversion (AMI), to solve the GE. We compare the performance of the AMI to other existing algorithms. Comparison between different techniques to form the GE is also compared. The MSINR based beamforming is demonstrated to be superior to the MSNR based beamforming in the presence of strong interference.
There are Pilot Symbol Assisted (PSA) beamforming techniques that exploit the Minimum Mean Squared Error (MMSE) criterion. We compare the MSINR based Beamformer-Rake with the same that utilizes Direct Matrix Inversion (DMI) to perform MMSE based beamforming in terms of Bit Error Rate (BER). In a wireless system where the number of co-channel interferers is larger than the number of elements of a practical antenna array, we can not perform explicit null-steering. As a result the advantage of beamforming is partially lost. In this scenario it is better to attain diversity gain at the cost of spatial aliasing. We demonstrate this with the aid of simulation.
Orthogonal Frequency Division Multiplexing (OFDM) is a multi-carrier technique that has recently received considerable attention for high speed wireless communication. OFDM has been accepted as the standard for Digital Audio Broadcast (DAB) and Digital Video Broadcast (DVB) in Europe. It has also been established as one of the modulation formats for the IEEE 802.11a wireless LAN standard. OFDM has emerged as one of the primary candidates for the Fourth Generation (4G) wireless communication systems and high speed ad hoc wireless networks. We propose a simple pilot symbol assisted frequency domain beamforming technique for OFDM receiver and demonstrate the concept of sub-band beamforming. Vector channel models measured with the MPRG Viper test-bed is also employed to investigate the performance of the beamforming scheme.Ph. D.
41
Tin, Noel Tai-Tung. "An experimental system for characterizing wideband CDMA vector channels and smart antennas." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ55935.pdf.
Full text
42
Pan, Yaobin. "Impact of DOA (direction of arrival) : in 4G MIMO Systems." Thesis, Linnéuniversitetet, Institutionen för fysik och elektroteknik (IFE), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-42158.
Full text
43
Petrus, Paul. "Novel Adaptive Array Algorithms and Their Impact on Cellular System Capacity." Diss., Virginia Tech, 1997. http://hdl.handle.net/10919/30375.
Full textAbstract:
This report focuses on the application of adaptive arrays to the Advanced Mobile Phone Service (AMPS) and Code Division Multiple Access (CDMA) cellular systems. Adaptive arrays have been proposed as early as in the 1960s to improve the signal quality, but most of its applications were restricted to defense purposes. Recently, there has been a surge in interest of applying adaptive arrays for cellular systems. This work introduces new blind adaptive array algorithms for AMPS and CDMA signals. The theoretical capacity limit using an adaptive array at the base station for an AMPS cellular system is derived in this work. One of the significant contributions in this research is a macrocell channel model which provides angle-of-arrival (AOA) statistics of the multipath components. Practical issues involved in the implementation of an adaptive array are addressed and the author's implementation of an 8-element adaptive array operating at 2.05 GHz is explained. This research also analyzes the capacity that can be o ered by an adaptive array in a system where CDMA users co-exist with existing AMPS users. A novel cellular CDMA system which exploits adaptive arrays is introduced and the capacity o ered by this system is compared with existing and other systems exploiting spatial dimension.Ph. D.
44
Juswardy, Budi. "Integrated broadband microphotonic beamformer for adaptive nulling in smart antennas." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2010. https://ro.ecu.edu.au/theses/1843.
Full textAbstract:
The tremendous growth of the wireless communications sector and the problem of limited available spectrum that can be used to cater the wireless demand have spurred the need for better data transmission capacity and signal rates for wireless communication systems. Smart antennas are the promising technology for improving the wireless communication systems performance. Smart antennas are system that consist of antenna arrays capable of adaptively adjusting the beam pattern, thereby enhancing the desired signals (beam steering) and suppressing the interference signals (null steering), which is also known as Space Division Multiple Access (SDMA). SDMA systems allow significant improvement in the area of capacity, signal bandwidth, signal-to-interference ratio, and frequency reuse. Due to the increasing complexity of the smart antennas system, innovations and improvements in miniaturisation, power consumption, and cost are needed. These breakthroughs could be achieved by combining the microelectronic and photonic technologies, leading to an innovative software-driven broadband MicroPhotonic beamforming system.
This thesis presents a doctoral study of integrated MicroPhotonic smart antenna beamformers. The beamformers presented in this study is based on microminiaturisation of hotonic and electronic components, which processes RF-modulated optical signals and adaptively synthesises multiple broadband null for interference suppression. Two types of beamformer are investigated in this thesis; the first form is based on delaying the input RF signal via discrete, high-resolution true-time delay (TTD) through the use of free space optics. The second type is based on continuous TTD generation using an Opto-VLSI processor in conjunction with high-dispersive optical fibres.
Design, simulation and proof-of-concept demonstration of some of the photonic building blocks and RF components of smart antennas that employ the MicroPhotonic beamformer are presented. These smart antennas are designed for use in adaptive broadband phased-array antenna applications including multimedia wireless transmission and RADAR.
45
Khosrowabadi, Allen, Richard Gurr, and Amy Fleishans. "SUBMINIATURE GPS INERTIAL TIME SPACE POSITION INFORMATION." International Foundation for Telemetering, 2000. http://hdl.handle.net/10150/608299.
Full textAbstract:
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, CaliforniaIn the past few years, GPS has proven itself as an effective source of time space position information (TSPI) data for air vehicles. Currently, GPS truth systems are used to track aircraft ranging from low dynamic vehicles to high dynamic fighters. However, low-cost GPS TSPI instrumentation is not currently available for stores and weapons delivered by air vehicles. To date, data is collected by tracking dropped items using radar or optical means. This process is costly and time consuming. The purpose of this project is to leverage the recent advances in micro-electromechanical systems (MEMS) technology to develop a subminiature, inexpensive, low power, disposable telemetrytransmitting package. The purpose of this transmitting package is to up-link the GPS positional data from the weapon or store to the host aircraft. This data is then retransmitted by the host aircraft to a ground station and/or recorded on board for post processing. The transmission of the data to the host aircraft can provide near real- time position data for the released object. The transmitting package must have a unique identification method for application in tracking multiple objects. Since most of the systems used in weapons testing will be destroyed, it is extremely important to keep the development and maintenance cost low. In addition, the package must be non-intrusive to avoid any significant modification to the weapon and to facilitate quick instrumentation of the weapon for test and evaluation.
46
PAIVA, ANA PAULA DE LACERDA. "PERFORMANCE OF JOINT DETECTION RECEIVERS TD/CDMA SYSTEM WITH AND WITHOUT USING SMART ANTENNAS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 1999. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=7269@1.
Full textAbstract:
COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIORSeveral multiple acess techniques are under discussion for third generation cellular systems. One of them is based on a hybrid time division, code division multiple acess (TD/CDMA). Since in this acess technique all users sharing the same slot are time synchronized, it is possible to jointly detect the different user signals arriving at the base station, eliminating both intersymbol and multiple acess interferences. Besides the use of techniques aiming to improve the receiver performance, another way to increase the capacity of a cellular system is adaptive antennas at the base station. A simulation tool was developed to verify the performance of a TD/CDMA system with with and without joint detection in three different situations: varying the number of simultaneous active users, in presence of failures on the power control mechanism and in presence of imprecisions of the channel estimator. It was compared also the performance of both receivers considering the effects of using smart antennas. The obtained results indicate that, in spite of increasing system complexity, the use of joint detection receivers might be a better option since its performance wes shown to be significantly better than that of conventional CDMA receivers.
Várias técnicas de múltiplo acesso estão sob discussão para sistemas celulares de 3a. geração. Uma delas é baseada em um sistema híbrido TD/CDMA (Time Division, Code Division Multiple Access). Neste sistema os sinais de todos os usuários simultaneamente ativos são síncronos, o que permite o emprego de receptores de detecção conjunta. Estes receptores conseguem cancelar idealmente as componentes de interferência de múltiplo acesso e entre símbolos e assim apresentam desempenho superior aos receptores CDMA convencionais. Além do desenvolvimento de receptores com melhor desempenho, outra técnica para aumentar a capacidade dos sistemas celulares é o emprego de antenas inteligentes. Neste trabalho, uma ferramenta de simulação foi desenvolvida para verificar o desempenho de sistemas TD/CDMA com e sem o emprego de receptores de detecção conjunta, em três situações: com a variação do número de usuários, considerando-se falhas no mecanismo de controle de potência e de estimação do canal. Adicionalmente, foi estudada a conveniência do emprego antenas inteligentes em conjunto com receptores CDMA convencionais e com detecção conjunta. Os resultados obtidos indicam que, apesar de aumentar a complexidade do sistema, o uso de receptores de detecção conjunta é bastante atraente, já que seu desempenho mostrou-se significativamente superior ao dos receptores CDMA convencionais.
47
Do-Hong, Tuan [Verfasser]. "Wideband Direction-of-Arrival Estimation and Wideband Beamforming for Smart Antenna Systems / Tuan Do-Hong." Aachen : Shaker, 2004. http://d-nb.info/1170534392/34.
Full text
48
Newhall, William George. "Radio Channel Measurements and Modeling for Smart Antenna Array Systems Using a Software Radio Receiver." Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/27115.
Full textAbstract:
This dissertation presents research performed in the areas of radio wave propagation measurement and modeling, smart antenna arrays, and software-defined radio development. A four-channel, wideband, software-defined receiver was developed to serve as a test bed for wideband measurements and antenna array experiments. This receiver was used to perform vector channel measurements in terrestrial and air-to-ground environments using an antenna array. ent results served as input to radio channel simulations based on three geometric channel models. The simulation results were compared to measurement results to evaluate the performance of the radio channel models under test. Criteria for evaluation include RMS delay spread, excess delay spread, signal envelope fading, antenna diversity gain, and gain achieved through the use of a two-dimensional rake receiver.
This research makes contributions to the wireless communications field through analysis, development, measurement, and simulation that builds upon past theoretical and experimental results. Contributions include a software-defined radio architecture, based on object oriented techniques, that has been developed and successfully demonstrated using the wideband receiver. This research has produced new wideband vector channel measurements to provide extensive characterization results facilitating simulation of emerging wireless technology for commercial and military communications systems. Original ways of interpreting multipath component strength and correlation for antenna arrays have been developed and investigated. A novel geometric air-to-ground ellipsoidal channel model has been developed, simulated, and evaluated. Other contributions include an evaluation of two popular radio channel models, a geometric channel simulator for producing channel impulse responses, and analytical derivation results related to channel modeling geometries and multipath channel measurement processing.
In addition to new results, existing theory and earlier research results are discussed. Fundamental theory for antenna arrays, vector channels, multipath characterization, and channel modeling is presented. Contemporary issues in software radio and object orientation are described, and measurement results from other propagation research are summarized.Ph. D.
49
De, Kuo Ren, and 郭仁德. "Design of 2.4GHz Smart Antenna System Testbed." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/89717646372452611148.
Full textAbstract:
碩士中原大學
電子工程學系
88
In wireless communication, smart antenna system can be used to suppress multipath fading by antenna diversity and increase system capacity by supporting multiple cochannel users in reception and transmission. The purpose of this thesis is to design a testbed, which has the function of smart antenna system. This testbed is helpful for the research, evaluation and provability of smart antenna system algorithm and vector propagation channel modeling. First, we''re going to introduce the specifications of this system, also the circuit design and fabrication for the three main modules (RF module, Baseband module and Common module), which comprise this testbed. The RF module consists of transmitter and receiver unit . Most of the components in the above unit have been tested and meet the specifications. The Baseband module consists of DAQ unit and I/O interface. Circuits of DAQ unit have been designed and realized. Also the control programs between I/O interface and the control unit of common module have been finished and an elementary test has been done. The Common module consists of synthesizer, control unit and mother broad. The synthesizer has been realized and tested, and the circuits of mother broad have been designed well.
50
Kao, Ming-tse, and 高銘澤. "Indoor Location Estimation Using Smart Antenna System." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/51559282224551739713.
Full textAbstract:
碩士國立中央大學
通訊工程研究所
100
During the last few years, Wireless LAN (WLAN) has been rapidly growing and becoming more and more popular. In particular, the techniques of indoor location estimation are receiving a lot of attentions due to wide variety of service such as building the medical health care, tracking people for security issue, sustaining emergency supplement system, providing directional guidance, and so on. With the matured indoor location technology, the new demand on wireless applications is location-based service (LBS). It is toward the usage for the business, public securities and safety requirements. Therefore, increasing the accuracy of positioning is a significant issue for indoor location technologies. In indoor environments, the shadowing of positioning environment, the multi-path and reflection phenomenon make the position estimation inaccurate. In traditional location fingerprint method shows that more Access Point (AP) deployments can obtain enough Receive Signal Strength (RSS) information to describe signal characteristics of the target space. However, it does not make sense and increase waste costs. On the other hand, insufficient AP deployments would significantly downgrade the accuracy of position estimation, because RSS information which is measured for the target object could be not enough. This thesis provides a novel indoor positioning solution to increase the accuracy of location estimation by gathering abundant RSS from the AP which has multi-antennas architecture. Since the AP equipped multi-antennas, the AP gathers RSS from all of antenna sets periodically. This system obtains enough RSS to compute the user position. Experimental results show that the proposed indoor location estimation demonstrates a high accuracy of positioning and outstanding performance while RSS is collected by smart antenna technique. Our proposed method not only achieves the high-precision positioning but also provides a rational deployments of cost in indoor location environments. The numerical results show that the accuracy is increased from 1.34% to 92.4% and the error variance is reduced by 96% as compared to the traditional location fingerprint method.