Journal articles: 'Multipath channels'

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Materum, Lawrence, and Antipas T. Teologo Jr. "An Improved K-Power Means Technique Using Minkowski Distance Metric and Dimension Weights for Clustering Wireless Multipaths in Indoor Channel Scenarios." Journal of Information and Communication Technology 20, No.4 (September 27, 2021): 541–63. http://dx.doi.org/10.32890/jict2021.20.4.4.

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Wireless multipath clustering is an important area in channel modeling, and an accurate channel model can lead to a reliable wireless environment. Finding the best technique in clustering wireless multipath is still challenging due to the radio channels’ time-variant characteristics. Several clustering techniques have been developed that offer an improved performance but only consider one or two parameters of the multipath components. This study improved the K-PowerMeans technique by incorporating weights or loads based on the principal component analysis and utilizing the Minkowski distance metric to replace the Euclidean distance. K-PowerMeans is one of the several methods in clustering wireless propagation multipaths and has been widely studied. This improved clustering technique was applied to the indoor datasets generated from the COST 2100 channel Model and considered the multipath components’ angular domains and their delay. The Jaccard index was used to determine the new method’s accuracy performance. The results showed a significant improvement in the clustering of the developed algorithm than the standard K-PowerMeans.

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Zhengyuan Xu. "Multipath CDMA channels." IEEE Transactions on Signal Processing 49, no. 9 (2001): 2003–17. http://dx.doi.org/10.1109/78.942629.

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Ng, Benjamin K., and Chan-Tong Lam. "Single-Carrier Rotation-Interleaved Space-Time Code for Frequency-Selective Fading Channels." Applied Sciences 12, no. 24 (December 13, 2022): 12803. http://dx.doi.org/10.3390/app122412803.

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A novel single-carrier-based space-time code construction scheme to exploit the advantages of a frequency-selective fading channel is investigated in this paper. The proposed construction scheme is based on multiplexing independent streams of phase-rotated space-time codes in a time-interleaved fashion. The advantage of such design is that it guarantees full space-time-multipath diversity by using traditional space-time codes or MIMO signaling schemes originally designed for flat fading channels as the constituent codes. Another advantage is that this approach incurs no loss in bandwidth efficiency and it alleviates the problem of high PAPR in OFDM-based space-time codes. By employing random or algebraic rotations, the design is potentially suitable for any number of transmit antennas or multipaths. The simulation results indicate that full space-time-multipath diversity is attained using this new approach, and comparisons with some existing space-time codes designed for frequency-selective channels are made to show its performance advantage.

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Gajanada, I. Gede Arya Gangga, Nyoman Pramaita, and I. Gusti Agung Komang Diafari Djuni Hartawan. "Design of Orthogonal Variable Spreading Factor (OVSF) Performance Simulation Program in Multipath Fading Channels." Journal of Electrical, Electronics and Informatics 4, no. 2 (August 31, 2020): 64. http://dx.doi.org/10.24843/jeei.2020.v04.i02.p05.

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The characteristics of wireless channel are determined by multipath propagation. The transmitted signal will be scattered so that it produces fading. Fading influenced by multipath component will cause delay spread which damages the signal. Thus, spread spectrum technology is used by using a bandwidth that is greater than the original signal. The objective of this study was to determine the effect of the number of multipath components on orthogonal variable spreading factor (OVSF) codes on multipath fading channels viewed from values and Bit Error Rate (BER) graphs versus Energy Bits per Noise (Eb/No). This study would compare the performance of OVSF code communication system on multipath channels by varying multipath components of 4, 8, 12, 16 and the length of OVSF codes used of 16, 8 and 4. The simulation results showed an increase in BER values when the number of multipath components was added. The more the number of multipath components used, the more the number of reflected signals that will interfere with the desired signal in the receiver. The length of the OVSF code influences the performance of the OVSF code on the multipath fading channel, because each code has a different processing gain value that is affected by the length of the code used

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A. Rida, Jafaar Fahad. "Improvement for performance radio frequency in wireless communication based on impulse signal." Indonesian Journal of Electrical Engineering and Computer Science 18, no. 2 (May 1, 2020): 903. http://dx.doi.org/10.11591/ijeecs.v18.i2.pp903-916.

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This research presents the improved performance of mobile wireless communication channel is based on non-line of sight because the mobile propagation channel is very hard to work with direct path between the transmitter and mobile receiver because of city-based area has objects such as rise building, trees, surround structures, and other objects. The mobile wireless spread radio channels have radio propagation mechanisms as a reflection, diffraction, and scattering effect on radio signal as lessening, and distortion or spread time. The most important thing to make real is that the wireless channel is a multipath radio channel. Multipath copies of the same signal with distinct amplitudes, stages and delay times for all multipaths between the transmitter and the receiver. The multipath fading is defined by its impulse response, which includes the facts about the relative time of the recipient's arrival of various indices of multipath additives. The impulse response expresses great characteristics in the time domain such the large bandwidth frequencies and the amplitude output only the value impulse response δ(t) equal to one when the value of time t=0, otherwise, the value impulse response δ(t) equal to zero in all values of the time. Over a time period reaction, the cellular radio channel could be designed as a linear filter with various impulses.

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Leftah, Hussein. "Performance Evaluation of DHT Based Optical OFDM for IM/DD Transmission Over Diffused Multipath Optical Wireless Channel." Iraqi Journal for Electrical and Electronic Engineering 15, no. 1 (June 1, 2019): 72–75. http://dx.doi.org/10.37917/ijeee.15.1.7.

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Optical OFDM based on discrete Hartley transform (DHT-O-OFDM) has been proposed for large-size data mapping intensity modulation direct detection (IM/DD) scheme as an alternative to the conventional optical OFDM. This paper presents a performance analysis and evaluation of IM/DD optical DC-biased DHT-O-OFDM over diffused multipath optical wireless channels. Zero-padding guard interval along with minimum mean-square error (MMSE) equalizer are used in electrical domain after the direct detection to remove the intersymbol interference (ISI) and eliminate the deleterious effects of the multipath channels. Simulation results show that the ZP-MMSE can effectively reduce the effects of multipath channels. The results also show that the effects of optical wireless multipath channel become more serious as the data signaling order increases.

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Jiang, Ting, Maozhong Song, Xiaorong Zhu, and Xu Liu. "Channel Estimation for Broadband Millimeter Wave MIMO Systems Based on High-Order PARALIND Model." Wireless Communications and Mobile Computing 2021 (November 23, 2021): 1–12. http://dx.doi.org/10.1155/2021/6408442.

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Channel state information (CSI) is important to improve the performance of wireless transmission. However, the problems of high propagation path loss, multipath, and frequency selective fading make it difficult to obtain the CSI in broadband millimeter-wave (mmWave) system. Based on the inherent multidimensional structure of mmWave multipath channels and the correlation between channel dimensions, mmWave multiple input multiple output (MIMO) channels are modelled as high-order parallel profiles with linear dependence (PARALIND) model in this paper, and a new PARALIND-based channel estimation algorithm is proposed for broadband mmWave system. Due to the structural property of PARALIND model, the proposed algorithm firstly separates the multipath channels of different scatterers by PARALIND decomposition and then estimates the channel parameters from the factor matrices decomposed from the model based on their structures. Meanwhile, the performance of mmWave channel estimation is analysed theoretically. A necessary condition for channel parameter estimation is given based on the uniqueness principle of PARALIND model. Simulation results show that the proposed algorithm performs better than traditional compressive sensing-based channel estimation algorithms.

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Singh, Rupender, and Meenakshi Rawat. "Closed-form Distribution and Analysis of a Combined Nakagami-lognormal Shadowing and Unshadowing Fading Channel." Journal of Telecommunications and Information Technology, no. 4 (December 30, 2016): 81–87. http://dx.doi.org/10.26636/jtit.2016.4.765.

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The realistic wireless channels face combined (time shared) Nakagami-lognormal shadowing and unshadowing fading because of time varying nature of radio channel and mobile user. These channels can be modeled as time-shared sum of multipath-shadowing and unshadowing Rician distributions. These fading create severe problems in long distance wireless systems where multipath fading is superim-posed on shadowing fading (called multipath-shadowing fading). The multipath effect can be modeled using Rayleigh, Rician, Nakagami-m or Weibull distribution and shadowing effect is modeled using lognormal distribution. In this paper, authors present a new closed-form probability distribution function of a Nakagami-lognormal fading channel. Using this result, the closed-form expression of combined Nakagami-lognormal shadowing and unshadowing fading is presented. The obtained closed-form result facilitates to derive the important performance metrics of a communication system such as amount of fading, outage probability, and average channel capacity in closed-form expressions.

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Xia, Wenhe, Wenting Guan, Zujun Jiang, Yingfeng Meng, and Bo Tang. "Modeling and measurement of microwave propagation multipath channels in drill pipe bore." International Journal of Microwave and Wireless Technologies 11, no. 3 (September 28, 2018): 220–26. http://dx.doi.org/10.1017/s1759078718001277.

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AbstractIn this paper, the characteristics of microwave propagation channels in drill pipe bore are analyzed by regarding the drill pipe as an irregular lossy cylindrical waveguide. An attenuation law is modeled using multipath propagation theory and an experimental statistical method. It is shown from physical measurement results that 5″ and $5^{1/2 \prime \prime} $ drill pipe bores, widely applied in the field of air drilling, can be used as 2.4 GHz band microwave channels with the caveat that the numerous reflective surfaces in the joint section of the drill pipe produce a great deal of reflected waves. Hence, the drill pipe bore has the characteristics of a dual cluster multipath channel, and multipath fading and delay are the primary factors affecting propagation quality. The study's constructed microwave attenuation model, based on multipath channels, can be regarded as the average attenuation of the unit length in the drill pipe bore, and can be used as the basis for simulation and analysis of the longer drill pipe string. In addition, a large delay between the two clusters leads to a significant increase of the root mean square delay spread. Consequently, multipath fading and delay are the main factors affecting the channel transmission rate.

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Pan, Chenyu, Songzuo Liu, Xin Qing, and Gang Qiao. "Feature extraction and classification of deep-sea mobile underwater acoustic channels." Journal of the Acoustical Society of America 154, no. 4_supplement (October 1, 2023): A309. http://dx.doi.org/10.1121/10.0023625.

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The reliable acoustic path (RAP) is one of the crucial channels for deep-sea sound propagation, which is affected weakly by the interface and has lower transmission loss, enabling long-distance communication. However, RAP-based deep-sea acoustic communication may face channel model mismatch issues. In order to analyze the dynamic characteristics of spatial-temporalvariability channels, deep-sea mobile underwater acoustic channel measurement experiments were conducted. This work proposes a deep learning method based on multi-dimensional properties to classify deep-sea channels. Specifically, the sound ray convergence zone leads to a complex multipath structure and severe delay spread in the RAP channel. The fuzzy c-means (FCM) algorithm is used for multipath clustering to extract accurate channel features, and then the Markov chain (MC) is introduced to track the evolution characteristics of multipath clusters. Finally, the coupling features of channel time-variant impulse response (TVIR) and multi-dimensionalstatistical properties are used as the input of convolutional neural networks (CNNs) to obtain the quantitative evaluation index as the channel classification to build a channel feature dataset for underwater mobile platforms. This dataset can effectively assist in identifying deep-sea mobile channels and promote the development of adaptive underwater acoustic communication systems on mobile platforms.

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Nowak, Thorsten, and Andreas Eidloth. "Dynamic multipath mitigation applying unscented Kalman filters in local positioning systems." International Journal of Microwave and Wireless Technologies 3, no. 3 (March 25, 2011): 365–72. http://dx.doi.org/10.1017/s1759078711000274.

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Multipath propagation is still one of the major problems in local positioning systems today. Especially in indoor environments, the received signals are disturbed by blockages and reflections. This can lead to a large bias in the user's time-of-arrival (TOA) value. Thus multipath is the most dominant error source for positioning. In order to improve the positioning performance in multipath environments, recent multipath mitigation algorithms based upon the concept of sequential Bayesian estimation are used. The presented approach tries to overcome the multipath problem by estimating the channel dynamics, using unscented Kalman filters (UKF). Simulations on artificial and measured channels from indoor as well as outdoor environments show the profit of the proposed estimator model. Furthermore, the quality of channel estimation applying the UKF and the channel sounding capabilities of the estimator are shown.

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Khan, Alisha, and Saurabh Shrivastava. "Performance Evaluation of OFDM System with Rician, Rayleigh, Rayleigh with Awgn and Awgn Channel for Bluetooth, Fixed and Mobile Wimax Application." International Journal of Advance Research and Innovation 2, no. 2 (2014): 78–84. http://dx.doi.org/10.51976/ijari.221412.

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The emergence of WIMAX has attracted interest from wireless communication researchers. This paper discusses the OFDM for wireless communication. It include Bit Error Rate and Symbol Error Rate versus the ratio of bit energy to noise power spectral density (Eb/No) for different communication channels like AWGN channel, Rayleigh multipath channel, combined Rayleigh multipath with AWGN channel and Rician channel. The simulation is designed on computer MATLAB 9 version with 64-point FFT. It demonstrates that AWGN has better performance than any other channel. The BER of AWGN channel is 10-5 at 8dB SNR for Rayleigh multipath channel is 10-4.5 at 40dB SNR for Rayleigh multipath channel with AWGN is 10-4 at 30dB SNR and for Rician channel is 10-3 at 30dB SNR. The SER of AWGN channel is 0.02 at 12dB and approximately 0 at 14dB whereas SER for Rayleigh multipath channel with AWGN is 0.0009 at 30dB. So, AWGN channel has better SNR than any other channel. It can be used for OFDM Bluetooth 802.11g-2003, fixed WIMAX 802.16-2004 and mobile WIMAX 802.16e-2005

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Blanza, Jojo, Emmanuel Trinidad, and Lawrence Materum. "Scedasticity descriptor of terrestrial wireless communications channels for multipath clustering datasets." International Journal of Electrical and Computer Engineering (IJECE) 13, no. 6 (December 1, 2023): 6547. http://dx.doi.org/10.11591/ijece.v13i6.pp6547-6557.

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Fifth-generation (5G) wireless systems increased the bandwidth, improved the speed, and shortened the latency of communications systems. Various channel models are developed to study 5G. These channel models reproduce the stochastic properties of multiple-input multiple-output (MIMO) antennas by generating wireless multipath components (MPCs). The MPCs that have similar properties in delay, angles of departure, and angles of arrival form clusters. The multipaths and multipath clusters serve as datasets to understand the properties of 5G. These datasets generated by the Cooperation in Science and Technology 2100 (COST 2100), International Mobile Telecommunications-2020 (IMT-2020), quasi deterministic radio channel generator (QuaDRiGa), and wireless world initiative new radio II (WINNER II) channel models are tested for their homoscedasticity based on Johansen's procedure. Results show that the COST 2100, QuaDRiGa, and WINNER II datasets are heteroscedastic, while the IMT-2020 dataset is homoscedastic.

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Sanz-González, José L., Santiago Zazo, Iván A. Pérez-Álvarez, and Javier López-Pérez. "Multipath-channel estimation and application to ionospheric channels." Wireless Networks 17, no. 6 (June 12, 2011): 1461–73. http://dx.doi.org/10.1007/s11276-011-0358-3.

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She, Feng, Hsiao Hwa Chen, and Hongyang Li. "Joint Angular and Time Diversity of Multi-Antenna CDMA Systems in Wireless Fading Channels." International Journal of Wireless Networks and Broadband Technologies 1, no. 1 (January 2011): 1–14. http://dx.doi.org/10.4018/ijwnbt.2011010101.

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In this paper, a multi-antenna based receiver structure for direct sequence code division multiple access (DS/CDMA) system is proposed. The proposed scheme exploits the excellent time resolution of a CDMA RAKE receiver and uses an antenna array beamforming structure to resolve multipath returns in both angular and time domains. A much higher diversity gain than that based only on the time domain diversity can be achieved. This work suggests a new space-time diversity paradigm, namely angular-time diversity, which differs from traditional Alamouti-type space-time coded schemes. The impairments caused by multipath and multiuser interference are analyzed. The performance of the proposed receiver in multipath fading channel is explicitly evaluated. An expression for uncoded system bit error probability is derived. Simulation results show the performance improvement in terms of BER due to the use of multi-antenna in the receiver, and the results illustrate that the multi-antenna based receiver works effectively in resolving multipaths in both angular and time domains to achieve performance improvement due to angular and time diversity gain provided by the multi-antenna system.

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Ndzi, David L., Nick Savage, and Boris Gremont. "Spatial and Temporal Variation of Wideband Indoor Channels." International Journal of Antennas and Propagation 2010 (2010): 1–11. http://dx.doi.org/10.1155/2010/735434.

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Extensive studies of the impact of temporal variations induced by people on the characteristics of indoor wideband channels are reported. Singular Value Decomposition Prony algorithm has been used to compute the impulse response from measured channel transfer functions. The high multipath resolution of the algorithm has allowed a detailed assessment of the shapes of individual multipath clusters and their variation in time and space in indoor channels. Large- and small-scale analyses show that there is a significant dependency of the channel response on room size. The presence of people in the channel has been found to induce both signal enhancements and fading with short-term dynamic variations of up to 30 dB, depending on the number of people and their positions within the room. A joint amplitude and time of arrival model has been used to successfully model measured impulse response clusters.

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Tuzlukov, Vyacheslav. "Employment of Generalized Receiver for Group-Blind Intersymbol Detection in Downlink CDMA over Fading Multipath Channels." WSEAS TRANSACTIONS ON SYSTEMS AND CONTROL 16 (November 3, 2021): 541–59. http://dx.doi.org/10.37394/23203.2021.16.51.

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Group-blind multiuser detectors for uplink code-division multiple-access (CDMA) were developed by Wang and Host-Madsen. These detectors make use of the spreading sequences of known users to construct a group constraint to suppress the intracell interference. However, such techniques demand the estimation of the multipath channels and the delays of the known users. In the present paper, the blind generalized receiver is de-veloped for CDMA in fading multipath channels. The proposed generalized receiver utilizes the correlation in-formation between consecutively received signals to generate the corresponding group constraint. It is shown that by incorporating this group constraint, the proposed generalized receiver can provide different performance gains in both the uplink and downlink environments. Compared with the well-known group-blind detectors, our new methods only need to estimate the multipath channel of the desired user and do not require the channel es-timation of other users. Simulation results demonstrate that the proposed generalized receiver outperforms the conventional blind linear multiuser detectors.

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Widi Arjana Yasa, I. Ketut, Nyoman Pramaita, and Ni Made Ary Esta Dewi Wirastuti. "DESAIN PROGRAM SIMULASI UNJUK KERJA KODE LARGE KASAMI PADA SISTEM KOMUNIKASI DIRECT SQUENCE SPREAD SPECTRUM MELALUI KANAL MULTIPATH FADING." Jurnal SPEKTRUM 8, no. 3 (October 31, 2021): 51. http://dx.doi.org/10.24843/spektrum.2021.v08.i03.p7.

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Selection of Pseudo Noise (PN) code in CDMA multiple access is needed to overcomeproblems related to interference. In this study, we simulate the large kasami code with the aimof knowing the performance of the large kasami code on flat fading channels and frequencyselective fading channels with variations in the number of multipath components. The receiversystem uses a correlation receiver to correlate the code used by each user. The simulationresults from the performance of the large kasami code through the flat fading channel show thatthe simulation carried out is valid, where the simulation BER value is close to the flat theoreticalBER value. The frequency selective fading channel shows different BER values from variationsin the number of multipath components, where the multipath 60 component produces the worstBER value. Auto correlation code large kasami has a value when the time is not equal to zerowhich can interfere with the desired signal and there is a cross-correlation signal level value thatwill interfere with each other's users.

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Wilding, Thomas, Stefan Grebien, Ulrich Mühlmann, and Klaus Witrisal. "Accuracy Bounds for Array-Based Positioning in Dense Multipath Channels." Sensors 18, no. 12 (December 3, 2018): 4249. http://dx.doi.org/10.3390/s18124249.

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The accuracy of radio-based positioning systems will be limited by multipath interference in realistic application scenarios. This paper derives closed-form expressions for the Cramér–Rao lower bound (CRLB) on the achievable time-of-arrival (ToA) and angle-of-arrival (AoA) estimation-error variances, considering the presence of multipath radio channels, and extends these results to position estimation. The derivations are based on channel models comprising deterministic, specular multipath components as well as stochastic, diffuse/dense multipath. The derived CRLBs thus allow an evaluation of the influence of channel parameters, the geometric configuration of the environment, and system parameters such as signal bandwidth and array geometry. Our results quantify how the ToA and AoA accuracies decrease when the signal bandwidth is reduced, because more multipath will then interfere with the useful LoS component. Antenna arrays can (partly) compensate this performance loss, exploiting diversity among the multipath interference. For example, the AoA accuracy with a 16-element linear array at 1 MHz bandwidth is similar to a two-element array at 1 GHz , in the magnitude order of one degree. The ToA accuracy, on the other hand, still scales by a factor of 100 from the cm-regime to the m-regime because of the dominating influence of the signal bandwidth. The position error bound shows the relationship between the range and angle information under realistic indoor channel conditions and their different scaling behaviors as a function of the anchor–agent placement. Specular multipath components have a maximum detrimental influence near the walls. It is shown for an L-shaped room that a fairly even distribution of the position error bound can be achieved throughout the environment, using two anchors equipped with 2 × 2 -array antennas. The accuracy limit due to multipath increases from the 1–10-cm-range at 1 GHz bandwidth to the 0.5–1-m-range at 100 MHz .

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Keshvadi, Hatef, Ali Broumandan, and Gérard Lachapelle. "Spatial Characterization of GNSS Multipath Channels." International Journal of Antennas and Propagation 2012 (2012): 1–15. http://dx.doi.org/10.1155/2012/236464.

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There is a growing interest in detecting and processing Global Navigation Satellite System (GNSS) signals in indoors and urban canyons by handheld devices. To overcome the signal attenuation problem in such adverse fading environments, long coherent integration is normally used. Moving the antenna arbitrarily while collecting signals is generally avoided as it temporally decorrelates the signals and limits the coherent integration gain. This decorrelation is a function of the antenna displacement and geometry of reflectors and angle of arrival of the received signal. Hence, to have an optimum receiver processing strategy it is crucial to characterize the multipath fading channel parameters. Herein, Angle of Arrival (AoA) and Angle Spread (AS) along with signal spatial correlation coefficient and fading intensity in GNSS multipath indoor channels are defined and quantified theoretically and practically. A synthetic uniform circular array utilizing a right-hand circular polarized (RHCP) antenna has been used to measure the spatial characteristics of indoor GNSS fading channels. Furthermore, rotating effect of a circular polarized antenna on the synthetic array processing and AoA estimation has been characterized. The performance of the beamforming technique via array gain is also assessed to explore the advantages and limitations of beamforming in fading conditions.

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Allanki Sanyasi Rao and Kallepelli Srikanth, Karthik Kumar Vaigandla,. "Study of Modulation Schemes over a Multipath Fading Channels." International Journal for Modern Trends in Science and Technology 7, no. 10 (October 31, 2021): 34–39. http://dx.doi.org/10.46501/ijmtst0710005.

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Communications systems concerted over wireless channels depend on the environment. Communications system can be more reliable and efficient by properly analyzing wireless channels. Today's most important features are a high data rate and reliable performance to exploiting viable networks during this new information age. The channel is not time-invariant in wireless communication, so the received signal exhibits amplitude, phase, and angle variations due to multipath fading. Increasing data rates and reducing bandwidth make Orthogonal Frequency Division Multiplexing (OFDM) an important component of wireless communication systems. The OFDM technique uses many carriers very efficiently. With this scheme, interference is robustly reduced, and fading scenarios are easily accommodated. Analyzing digital modulation schemes requires evaluating link performance with fading channels. The paper compares channel performance over varying fading environments using a variety of modulation schemes. We study the BER and SNR properties of the AWGN, Rician fading and Rayleigh fading channels modulated with BPSK, QPSK, and M-ary QAM.

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Mohammed, Hasan Fadhil, and Ghanim Abdulkareem Mughir. "Performance evaluation of 4-quadrature amplitude modulation over orthogonal frequency division multiplexing system in different fading channels scenarios." International Journal of Electrical and Computer Engineering (IJECE) 12, no. 5 (October 1, 2022): 5123. http://dx.doi.org/10.11591/ijece.v12i5.pp5123-5135.

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Orthogonal frequency division multiplexing (OFDM) is a multicarrier modulation (MCM) technique that divides the wide bandwidth into parallel narrow bands, each of which is modulated by orthogonal subcarriers. Currently, OFDM is a high-spectral efficiency modulation technique that is used in a variety of wired and wireless applications. The transmitted signal in a wireless communication channel spreads from transmitter to receiver through multiple reflective paths. This triggers multipath fading, which causes variations in the received signal's amplitude and phase. Slow/fast and frequency-selective/frequency-nonselective are the main types of multipath fading channels. Therefore, in this paper, we proposed new models for modeling multipath fading channels, such as the exponential fading channel and the Gamma fading channel. In addition, new bit-error-rate (BER) derivations have been derived. The performance of the OFDM system over proposed channel models has been evaluated using Monte-Carlo simulation and compared to the Rayleigh fading channel model. The obtained results via simulations show that the exponential fading channel at a rate parameter (λ=0.5) outperforms the Rayleigh fading channel by 6 dB for all values of Eb/No, while the Gamma fading channel at (α=2) outperforms the Rayleigh fading channel by 3 dB for all values of Eb/No.

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Пензин, Максим, Maksim Penzin, Николай Ильин, and Nikolay Ilyin. "Modeling of Doppler frequency shift in multipath radio channels." Solar-Terrestrial Physics 2, no. 2 (August 10, 2016): 66–76. http://dx.doi.org/10.12737/21000.

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We discuss the modeling of propagation of a quasi-monochromatic radio signal, represented by a coherent pulse sequence, in a non-stationary multipath radio channel. In such a channel, signal propagation results in the observed frequency shift for each ray (Doppler effect). The modeling is based on the assumption that during propagation of a single pulse a channel can be considered stationary. A phase variation in the channel transfer function is shown to cause the observed frequency shift in the received signal. Thus, instead of measuring the Doppler frequency shift, we can measure the rate of variation in the mean phase of one pulse relative to another. The modeling is carried out within the framework of the method of normal waves. The method enables us to model the dynamics of the electromagnetic field at a given point with the required accuracy. The modeling reveals that a local change in ionospheric conditions more severely affects the rays whose reflection region is in the area where the changes occur.

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Zainul Halim, Muhamad, Nyoman Pramaita, and Pande Ketut Sudiarta. "SIMULASI KINERJA GOLD CODE PADA SISTEM KOMUNIKASI DIRECT SEQUENCE SPREAD SPECTRUM (DSSS) MELALUI KANAL MULTIPATH FADING." Jurnal SPEKTRUM 8, no. 2 (July 12, 2021): 257. http://dx.doi.org/10.24843/spektrum.2021.v08.i02.p29.

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The communication channel cannot be separated from noise, interference and fading.To minimize mutual interference, you can use a scatter code. This research uses Gold Codewith a code length of 31. This simulation aims to determine the effect of the number of multipathcomponents on the Gold Code performance of multipath fading channels. This simulation usesdigital modulation, namely BPSK (Binary Phase Shift Keying). In the simulation of flat fadingchannel with 1 multipath component number, the results of the comparison of simulated BERwith theoretical BER are almost the same so that the simulation results can be said to be validand can be used on selective fading channels. In the simulation of frequency selective fadingchannels with variations of multipath components have different values, this happens due tointerference. In this simulation, the number of multipath 27 components that have the mostdisruptive signals results in the worst performance. In multi-user cross-correlation, it has poorperformance, seen from the cross-correlation function, where the correlation value of user 1with 2, 3 and 4 is more than 0, this value indicates the user is being interfered with by otherusers.

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Rekkal, Kahina, Sara Rekkal, and Abdesselam Bassou. "Advanced hybrid algorithms for precise multipath channel estimation in next-generation wireless networks." International Journal of Electrical and Computer Engineering (IJECE) 14, no. 2 (April 1, 2024): 1654. http://dx.doi.org/10.11591/ijece.v14i2.pp1654-1664.

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Multipath channels continue to present challenges in wireless communication for both 5G and 6G networks. A multipath channel is a phenomenon in wireless communications where signals traverse from the sender to the receiver along various paths. This end occurs due to the reflection, diffraction, and refraction of signals of various objects and structures in the environment. Such pathways can cause symbol interference in the transmitted signal, leading to communication issues. To this end, our paper proposes the integration of three algorithms: teaching-learning-based optimization (TLBO), particle swarm optimization (PSO), and artificial neural networks (ANN). This combination effectively analyzes and stabilizes the transmission channel, minimizing symbol interference. We have developed, simulated, and evaluated this hybrid approach for multipath fading channels. We apply it to various coding schemes, including tail-biting convolutional code, turbo codes, low-density parity-check, and polar code. Additionally, we have explored various decoding methods such as Viterbi, maximum logarithmic maximum a posteriori, minimum sum, and cyclic redundancy check soft cancellation list. Our study encompasses new channel equalization schemes and coding gains derived from simulations and mathematical analysis. Our proposed method significantly enhances channel equalization, reducing interference and improving error correction in wireless communication systems.

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Jaime-Rodríguez, José Jimmy, Carlos Antonio Gómez-Vega, Carlos A. Gutiérrez, José Martín Luna-Rivera, Daniel Ulises Campos-Delgado, and Ramiro Velázquez. "A Non-WSSUS Channel Simulator for V2X Communication Systems." Electronics 9, no. 8 (July 24, 2020): 1190. http://dx.doi.org/10.3390/electronics9081190.

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This paper presents a simulator of non-wide sense stationary uncorrelated scattering (non-WSSUS) multipath fading channels for the performance analysis of vehicle-to-everything (V2X) communication systems. The proposed simulator is constructed with the combination of the Monte Carlo and sum-of-cisoids (SOC) principles, and it is suitable for multicarrier transmission schemes such as those defined for dedicated short-range communications (DSRC) and cellular-based V2X (C-V2X) communications. The channel simulator provides an accurate and flexible solution to reproduce the time and frequency (TF) correlation properties of non-WSSUS vehicular channels under arbitrary isotropic and non-isotropic scattering conditions. Furthermore, the proposed simulator allows velocity variations and non-linear trajectories of the mobile stations (MSs). To demonstrate the practical value of the presented simulator, we evaluate the bit error rate (BER) performance of two channel estimation techniques that are considered for IEEE 802.11p transceivers, namely the least squares (LS) estimator and the spectral temporal averaging (STA) technique. The BER performance of both channel estimators was analyzed by considering three propagating scenarios for road safety applications. Our results show that the non-stationary characteristics of the vehicular multipath fading channel have nearly no effects on the LS estimator’s BER performance. In contrast, the performance of the STA estimator is significantly affected by the channel’s non-stationary characteristics. A variation of the original STA technique that applies only a temporal averaging is introduced in this work to improve the system’s BER in non-WSSUS channels.

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Song, S. H., and Q. T. Zhang. "Mutual Information of Multipath Channels with Imperfect Channel Information." IEEE Transactions on Communications 57, no. 5 (May 2009): 1523–31. http://dx.doi.org/10.1109/tcomm.2009.05.070273.

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Hatzinakos, D., and C. L. Nikias. "Estimation of multipath channel response in frequency selective channels." IEEE Journal on Selected Areas in Communications 7, no. 1 (January 1989): 12–19. http://dx.doi.org/10.1109/49.16839.

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Manhas, Pratima, and M. K. Soni. "Performance of OFDM System under Different Fading Channels and Channel Coding." Bulletin of Electrical Engineering and Informatics 6, no. 1 (March 1, 2017): 54–61. http://dx.doi.org/10.11591/eei.v6i1.591.

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Orthogonal frequency division multiplexing (OFDM) is a type of multicarrier modulation (MCM) technique in which larger bandwidth is divided into parallel narrow bands each of which is modulated by different subcarriers. All the subcarriers are orthogonal to each other and hence it reduces the interference among various subcarriers. OFDM technique is an efficient modulation technique used in certain wired and wireless application.In a wireless communication channel, the transmitted signal can travel from transmitter to receiver over multiple reflective paths. This results to multipath fading which causes fluctuations in amplitude, phase and angle of arrival of the received signal. For example, the signal which is transmitted from BTS (base transceiver station) may suffer multiple reflections from the buildings nearby, before reaching the mobile station. Such multipath fading channels are classified into slow fading/fast fading and frequency-selective/flat fading channels. This paper discusses the performance of OFDM system using various fading channels and channel coding. The parameter which is known as Bit error rate (BER) is calculated under different fading channels (AWGN, Rayleigh and Rician) for different digital modulation (BPSK, QPSK and QAM) and Channel coding (linear/Cyclic coding). Matlab Simulink tool is used to calculate the BER parameter.

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Shinkevich, Artem, Dmitriy Pokamestov, Yakov Kryukov, Georgiy Shalin, Andrey Brovkin, and Eugeniy Rogozhnikov. "Evaluation of LDPC codes efficiency in channels with fading." E3S Web of Conferences 376 (2023): 01061. http://dx.doi.org/10.1051/e3sconf/202337601061.

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The article discusses the operation of communication systems using a low-density parity check codes in channels with multipath propagation. This class of codes has found wide application in modern communication and broadcasting systems and is one of the most effective in now. Some theoretical and practical issues of combating the effects arising from multipath propagation are presented. The description of the developed simulation model, channel codec, equalizer, and transmission channel is given. The channel encoder in the model is designed in accordance with the specifications for the 5G New Radio (5G NR) communication standard. The multipath parameters in the transmission channel correspond to the TDL models for 5G NR, with the exception of the Doppler shift, which is not taken into account in the simulation. In addition, there is additive interference in the channel. The decoding algorithm used was also described in detail. As a result of the study, the dependences of the bit error probability on the signal-to-noise ratio were obtained for the code rates 1/2 and 1/8, as well as for the system without coding. Based on the results obtained, it is possible to judge the correcting ability of this class of codes.

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Widi Adnyana, Komang Gede, Nyoman Pramaita, and I. Made Oka Widyantara. "UNJUK KERJA KODE ORTHOGONAL M-SEQUENCE DALAM SISTEM DIRECT SEQUENCE SPREAD SPECTRUM MELALUI KANAL MULTIPATH FA." Jurnal SPEKTRUM 9, no. 4 (December 19, 2022): 1. http://dx.doi.org/10.24843/spektrum.2022.v09.i04.p1.

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Multipath and multi-user interference are the main challenges in wireless communication systems. This has become a driving force for the development of data transmission technology that is focused to overcome these problems, one of which is spread spectrum. Spread spectrum is applied to CDMA technology which has the limitations of MAI, so a spreading code is required with specifications that have a very low cross-correlation value as in the orthogonal m-sequence code. In this study, simulate the orthogonal m-sequence code with a length of 8 chips on a multipath fading channel using the Direct Sequence Spread Spectrum system with aims of assessing the performance of the orthogonal m-sequence code on a multipath fading channel, based on the effect of changes in the number of multipath components. The research method used is a Monte Carlo simulation on simulink with the output data in the form of a graph of the comparison value of BER with Eb/No. The results show that on the flat fading channel with the number of components multipath 1, the BER value of the simulation results is in accordance with the BER theory so that the simulation is valid and can be applied to frequency selective fading channels. In the frequency selective fading channel with the number of multipath components 4,6, and 8, the best performance was shown in the multipath 4 component with the smallest BER value, this was influenced by the ACF and CCF values so that the multipath 4 component had the lowest ISI and interference between users.

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Chen, Jiajing, Xuefeng Yin, Li Tian, Nan Zhang, Yongyu He, Xiang Cheng, Weiming Duan, and Silvia Ruiz Boqué. "Measurement-Based LoS/NLoS Channel Modeling for Hot-Spot Urban Scenarios in UMTS Networks." International Journal of Antennas and Propagation 2014 (2014): 1–12. http://dx.doi.org/10.1155/2014/454976.

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A measurement campaign is introduced for modeling radio channels with either line-of-sight (LoS) or non-line-of-sight (NLoS) connection between user equipment (UE) and NodeB (NB) in an operating universal mobile telecommunications system. A space-alternating generalized expectation-maximization (SAGE) algorithm is applied to estimate the delays and the complex attenuations of multipath components from the obtained channel impulse responses. Based on a novel LoS detection method of multipath parameter estimates, channels are classified into LoS and NLoS categories. Deterministic models which are named “channel maps” and fading statistical models have been constructed for LoS and NLoS, respectively. In addition, statistics of new parameters, such as the distance between the NB and the UE in LoS/NLoS scenarios, the life-distance of LoS channel, the LoS existence probability per location and per NB, the power variation at LoS to NLoS transition and vice versa, and the transition duration, are extracted. These models are applicable for designing and performance evaluation of transmission techniques or systems used by distinguishing the LoS and NLoS channels.

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Cotae, Paul, and Matt Aguirre. "Method for Minimizing Total Generalized Squared Correlation of Synchronous DS-CDMA Signature Sequence Sets in Multipath Channels." Journal of Communications Software and Systems 2, no. 1 (April 6, 2017): 20. http://dx.doi.org/10.24138/jcomss.v2i1.302.

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We characterize the Total Generalized Squared Correlation (TGSC) for a given signature sequence set used in uplink synchronous code division multiple access (S-CDMA) when channel state information is known perfectly at bothtransmitter and receiver. We give a definition of the TGSC based on the eigenvalues of Gram matrix associated to signature sequences set for multipath channels in the presence of the colored noise. Total Squared Correlation (TSC) and Total Weighted Squared Correlation (TWSC) measures are particular cases of TGSC. We present a method for minimizing TGSC (TSC, TWSC) in multipath channels and in the presence of the colored noise. Numerical results for overloaded synchronous CDMA systems are presented in order to support our analysis.

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Marjanović, Zvezdan, Dejan N. Milić, and Goran T. Đorđević. "On Numerical Evaluation of Packet-Error Rate for Binary Phase-Modulated Signals Reception over Generalized-K Fading Channels." Facta Universitatis, Series: Mathematics and Informatics 33, no. 2 (September 7, 2018): 203. http://dx.doi.org/10.22190/fumi1802203m.

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We present a numerical evaluation of packet error rate (PER) for digital binary phase modulations over wireless communication channels. The analysis is valid for a quasistatic fading communication channel, where multipath fading and shadowing appear simultaneously. The approach is based on numerical evaluation of signal-to-noise ratio threshold that is further used in PER computation. We analyze the threshold and PER dependence on signal power, multipath fading and shadowing severity, as well as packet length.

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Sadrieh, Seyed Nima, Ali Broumandan, and Gérard Lachapelle. "Doppler Characterization of a Mobile GNSS Receiver in Multipath Fading Channels." Journal of Navigation 65, no. 3 (April 4, 2012): 477–94. http://dx.doi.org/10.1017/s037346331200015x.

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Global Navigation Satellite Systems (GNSS) Doppler measurements are commonly used for velocity-based relative positioning and aiding Inertial Navigation Systems (INS) in signal degraded environments. The aim of this paper is to characterise the Doppler measurements in GNSS harsh multipath environments. In multipath fading situations such as indoor and urban canyon environments, multipath components arrive to the receiver antenna from different paths and directions. These give rise to various Doppler shifts that cause errors in the velocity solution. In this work the Doppler measurements discrepancy characterised by Doppler spread in multipath environments is investigated. By assuming a ‘sphere of scatterers’ model and considering the antenna gain pattern, the theoretical Power Spectral Density (PSD) observed by a receiver is formulated. The theoretical findings are examined using two sets of measurements in dense multipath environments. Global Positioning System (GPS) live signals using non-isotropic antennas with different orientations are used for this purpose. Different motion directions are also examined using different data sets. An Assisted GPS (A-GPS) approach is utilised where the code phase and the navigation data bits are provided by a nearby outdoor antenna. By applying a ‘Block Processing’ technique, an epoch-by-epoch Doppler and velocity estimation is implemented. Herein, the Doppler and velocity measurements accuracy in addition to the Doppler spread characterization are studied. As shown both theoretically and experimentally, in harsh multipath environments the PSD of the observed signals is a function of the scatterers' geometry and the antenna gain pattern. The Doppler estimation accuracies in multipath and multipath-free cases are compared for different ranges of Carrier-to-Noise ratio (C/N0). Theoretical and experimental results revealed inaccurate Doppler estimation and poor Doppler-derived velocity solutions in dense multipath environments.

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McCarthy, Ryan A., Ananya Sen Gupta, and Madison Kemerling. "Estimation and interpretation of multipath channel activity using braiding techniques." Journal of the Acoustical Society of America 151, no. 4 (April 2022): A267. http://dx.doi.org/10.1121/10.0011295.

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Robust underwater acoustic channel estimation is critical towards improving communications efforts and enhancing awareness of changing environments. To explore these channels in-depth, machine learning algorithms are developed through feature geometric representations, referred to as “braiding,” to interpret multipath ray bundles within shallow water acoustic channels in two ways. The first application of this work predicts the number of reflections an acoustic signal may undergo through the environment by applying known physical parameters and braid features. The second application explores the importance of a braid feature within the acoustic channel for estimation purposes by using braid path information. Three unique machine learning techniques are trained to predict the applications using a diverse set of shallow water acoustic channels generated through the BELLHOP model. Machine learning models developed for the applications demonstrate high testing accuracies with an accuracy of 86.70% in the first application and an accuracy of 99.94% in the second application. As a further demonstration, braid feature representations and model predictions are used for channel estimation and determining the number of reflections using SPACE08 field data.

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Khan, Rehan, Qiao Gang, and Wang Wei. "Performance Evaluation of ZP-OFDM Scheme in Underwater Multipath Channel." Applied Mechanics and Materials 321-324 (June 2013): 2868–76. http://dx.doi.org/10.4028/www.scientific.net/amm.321-324.2868.

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One of the major problems while dealing with underwater acoustic communication (UWAC) is the occurrence of unwanted multipath having long delay spreads. Higher probability of reflections (from wavy sea surface, uneven sea bottom, other obstacles, etc.) and refraction of sound are the main causes of these grievous multipath signals. Multipath effects further offer severe degradation in the packet (s) and mutilation of entire signal in terms of inter-symbolic interference (ISI) is occurred. During last decade, multicarrier modulation in terms of OFDM was considered as one of the viable solutions to mitigate the multipath effect and provide high-rate communication. In this article, we are performing the practical evaluation of Zero-Padded Orthogonal Frequency Division Multiplexing (ZP-OFDM) based communication system. The data using various packet structures are used to demonstrate the effectiveness of ZP-OFDM scheme in the flat multipath channel of the water pool of acoustic lab, Harbin Engineering University. Satisfactory performance results are obtained even within high noisy environment. These results suggest that ZP-OFDM is a viable choice for high-rate communications over multipath induced underwater channels.

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Karbolin, V. A., and V. I. Nosov. "Recommendations for the modulation index choice of UWB radio systems with BPPM in indoor channels." Herald of the Siberian State University of Telecommunications and Informatics, no. 1 (May 13, 2022): 3–17. http://dx.doi.org/10.55648/1998-6920-2022-16-1-3-17.

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The impact of modulation index on the BER performance of BPPM in UWB radio is analyzed in multipath indoor channels. The recommendations for the optimal modulation index choice are drawn up with respect to minimum bit error rate in multipath indoor channel. The theoretical expression for BER performance of BPPM is derived. The BER performance figures for different data rates as a function of a signal to a noise ratio produced by using the theoretical expression and computer simulations are presented. MATLAB is used for computer simulations.

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Shostak, S. V., and A. V. Bengard. "Application of the Gauss–Markov Theorem for Equalization of a Hydroacoustic Transmission Channel." LETI Transactions on Electrical Engineering & Computer Science 17, no. 1 (2024): 13–18. http://dx.doi.org/10.32603/2071-8985-2024-17-1-13-18.

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Researchers in the field of modern hydroacoustics frequently encounter such problems as interference and noise in communication channels. Multipath propagation is an inevitable hydroacoustic communication problem arising in a sound channel due to reflections from the water surface and seabed. In general, this may decrease the overall communication quality. As a rule, noise cannot be completely eliminated, although its influence can be minimized. In this article, we describe a method for equalizing the hydroacoustic transmission channel using the Gauss–Markov theorem. This method can be used for reducing the multipath propagation effect and obtaining an unbiased estimate with minimal variance.

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Do-Sik Yoo and W. E. Stark. "Characterization of multipath fading channels: channels with specular components." IEEE Transactions on Wireless Communications 4, no. 4 (July 2005): 1471–82. http://dx.doi.org/10.1109/twc.2005.847092.

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Xie, Yong Gang, and Dong Ya Shen. "A Novel Hybrid Algorithm for Equalization of WBAN Channel." Applied Mechanics and Materials 543-547 (March 2014): 1868–71. http://dx.doi.org/10.4028/www.scientific.net/amm.543-547.1868.

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Equalization technology is important in WBAN channels for resolving ISI problem. However, traditional algorithms, such as LMS and RBF are not suitable to be applied in WBAN channel, due to the fact that channels of WBAN are particularly time variable and have severe multipath effect. In this study, we proposed a novel hybrid algorithm by combining NFN and RBFN algorithms. Experimental results show better performance compared to both NFN and RBFN algorithms in prediction problem in WBAN Channels.

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42

T.S., Kavya, and Sunil Jacob. "Energy Efficient TRDMA over Multipath Channels." Communications on Applied Electronics 2, no. 7 (August 25, 2015): 6–11. http://dx.doi.org/10.5120/cae2015651797.

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43

Medard, M., and R. G. Gallager. "Bandwidth scaling for fading multipath channels." IEEE Transactions on Information Theory 48, no. 4 (April 2002): 840–52. http://dx.doi.org/10.1109/18.992769.

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Cable, Peter. "Statistical characterization of multipath sound channels." Journal of the Acoustical Society of America 132, no. 3 (September 2012): 1931. http://dx.doi.org/10.1121/1.4755096.

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Raviteja, P., Emanuele Viterbo, and Yi Hong. "OTFS Performance on Static Multipath Channels." IEEE Wireless Communications Letters 8, no. 3 (June 2019): 745–48. http://dx.doi.org/10.1109/lwc.2018.2890643.

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Mehmood, Rashid, Jon W. Wallace, and Michael A. Jensen. "Secure Array Synthesis in Multipath Channels." IEEE Transactions on Antennas and Propagation 66, no. 7 (July 2018): 3383–90. http://dx.doi.org/10.1109/tap.2018.2829838.

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Sylvain, M. "Experimental probing of multipath microwave channels." Radio Science 24, no. 2 (March 1989): 160–78. http://dx.doi.org/10.1029/rs024i002p00160.

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Samosir, Pebri Yeni, Nyoman Pramaita, I. Gst A. Komang Diafari Djuni Hartawan, and Ni Made Ary Esta Dewi Wirastuti. "Performance Analysis of MIMO STBC System in Flat Fading and Frequency Selective Fading Channels." Journal of Electrical, Electronics and Informatics 3, no. 1 (June 18, 2019): 19. http://dx.doi.org/10.24843/jeei.2019.v03.i01.p04.

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Multiple Input Multiple Output (MIMO) technology is a technique that can be used to overcome multipath fading. The multipath fading is caused by signals coming from several paths that experience different attenuations, delays and phases. In a multipath condition, an impulse that sent by the transmitter, will be received by the recipient not as an impulse but as a pulse with a spread width that called delay spread. Delay spread can cause intersymbol interference (ISI) and bit translation errors from the information received. To determine the effect of delay spread on the MIMO system, then MIMO system performance research was performed on flat fading and frequency selective fading channels using the Space Time Block Code (STBC) coding technique. This research was conducted using MatLab 2018a software. The simulation results show that the MIMO STBC system performance on flat fading channels is better than the MIMO STBC system performance on the frequency selective fading channel. This result is analyzed based on the value of BER vs. Eb/No and eye diagram.

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Li, Yingsong, Zhan Jin, and Yanyan Wang. "Adaptive Channel Estimation Based on an Improved Norm-Constrained Set-Membership Normalized Least Mean Square Algorithm." Wireless Communications and Mobile Computing 2017 (2017): 1–8. http://dx.doi.org/10.1155/2017/8056126.

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An improved norm-constrained set-membership normalized least mean square (INCSM-NLMS) algorithm is proposed for adaptive sparse channel estimation (ASCE). The proposed INCSM-NLMS algorithm is implemented by incorporating an lp-norm penalty into the cost function of the traditional set-membership normalized least mean square (SM-NLMS) algorithm, which is also denoted as lp-norm penalized SM-NLMS (LPSM-NLMS) algorithm. The derivation of the proposed LPSM-NLMS algorithm is given theoretically, resulting in a zero attractor in its iteration. By using this proposed zero attractor, the convergence speed is effectively accelerated and the channel estimation steady-state error is also observably reduced in comparison with the existing popular SM-NLMS algorithms for estimating exact sparse multipath channels. The estimation behaviors are investigated via a typical sparse wireless multipath channel, a typical network echo channel, and an acoustic channel. The computer simulation results show that the proposed LPSM-NLMS algorithm is better than those corresponding sparse SM-NLMS and traditional SM-NLMS algorithms when the channels are exactly sparse.

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Kong, Lingjin, Xiaoying Zhang, Haitao Zhao, and Jibo Wei. "Variational Sparse Bayesian Learning for Estimation of Gaussian Mixture Distributed Wireless Channels." Entropy 23, no. 10 (September 28, 2021): 1268. http://dx.doi.org/10.3390/e23101268.

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In this paper, variational sparse Bayesian learning is utilized to estimate the multipath parameters for wireless channels. Due to its flexibility to fit any probability density function (PDF), the Gaussian mixture model (GMM) is introduced to represent the complicated fading phenomena in various communication scenarios. First, the expectation-maximization (EM) algorithm is applied to the parameter initialization. Then, the variational update scheme is proposed and implemented for the channel parameters’ posterior PDF approximation. Finally, in order to prevent the derived channel model from overfitting, an effective pruning criterion is designed to eliminate the virtual multipath components. The numerical results show that the proposed method outperforms the variational Bayesian scheme with Gaussian prior in terms of root mean squared error (RMSE) and selection accuracy of model order.

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Journal articles on the topic 'Multipath channels'

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