Journal articles: 'Rayleigh fading channel'

1

Heider, Inaam Abbas. "Improvement of Fading Channel Modeling Performance for Wireless Channel." International Journal of Electrical and Computer Engineering (IJECE) 8, no. 3 (June 1, 2018): 1451. http://dx.doi.org/10.11591/ijece.v8i3.pp1451-1459.

Full text

Abstract:

Fading channel modeling is generally defined as the variation of the attenuation of a signal with various variables. Time, geographical position, and radio frequency which is included. Fading is often modeled as a random process. Thus, a fading channel is a communication channel that experiences fading. In this paper, the proposed system presents a new design and simulate a wireless channel using Rayleigh channels. Rayleigh channels using two approaches (flat and frequency-selective fading channels) in order to calculate some path space loss efforts and analysis the performance of different wireless fading channel modeling. The results show that the bite error rate (BER) performance is dramatically improved in the value of signal to noise ratio (SNR) is equal to 45dB. Finally, the experimental results show that the proposed method enhances the performance of fading channel modeling by reducing the error of BER when the SNR is reduced also. Moreover, the more accurate model is Rayleigh model which can be considered for developing fading channel model.

APA, Harvard, Vancouver, ISO, and other styles

2

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.

Full text

Abstract:

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.

APA, Harvard, Vancouver, ISO, and other styles

3

Gnanaselvam, R., and M. S. Vasanthi. "Coverage Optimization in LoRa with Diverse Fading Wireless Channels." Journal of Physics: Conference Series 2335, no. 1 (September 1, 2022): 012008. http://dx.doi.org/10.1088/1742-6596/2335/1/012008.

Full text

Abstract:

Abstract In LoRa (Long Range) network, the Probability of Coverage (PoCov) in the LoRa User Equipment (UEs) is evaluated in diverse fading wireless channels through closed expressions, particularly considering the distribution of Nakagami and Rayleigh wireless fading channels. The PoCov in Nakagami-m fading channel has been calculated approximately, similarly, the PoCov in Rayleigh fading channel was evaluated in an extract manner. Moreover, we see the effect of diverse interference under PoCov performance. In particular, consider interferences such as intra Spreading Factor (SF), inter SF, and both inter and intra SF.

APA, Harvard, Vancouver, ISO, and other styles

4

Ni'amah, Khoirun, Muhammad Panji Kusuma Praja, and Yuninda Dwianti Marimbun. "Comparative Analysis of 16-QAM and 64-QAM Modulation in Additive White Gaussian Noise and Rayleigh Fading Channels." CESS (Journal of Computer Engineering, System and Science) 7, no. 1 (December 27, 2021): 90. http://dx.doi.org/10.24114/cess.v7i1.26729.

Full text

Abstract:

This reseach simulates and analyzes paramaters bit error rate (BER) of 16-QAM and 64-QAM modulation on Additive White Gaussian Noise and Rayleigh Fading channels. This research aims to determine 5G modulation with the level of data quality after the transmission process is carried out. The modulation simulation results obtained will be compared with the theoretical bit error rate (BER). The simulation results obtained from the two channel scenarios used are 16-QAM modulation reaching BER 10-4, AWGN channel only requires 15 dB Eb/N0 and for Rayleigh Fading channel it requires 38 dB Eb/N0. The BER theoretical results obtained for the 16-QAM modulation of the AWGN channel have a difference of 3 dB with the simulation results, while for the Rayleigh Fading channel it is 5 dB. Then, the simulation results of 64-QAM modulation AWGN channel to achieve BER 10-4 requires Eb/N0 of 24.6 dB, Rayleigh Fading of 47 dB. The theoretical results of BER obtained for the 64-QAM modulation of the AWGN channel have a difference of 1 dB with the simulation results, while for the Rayleigh Fading channel it is 0.5 dB. In this study, between 16-QAM and 64-QAM 5G modulation is more suitable to use 16-QAM modulation because it requires less power to achieve the desired BER 10-4.

APA, Harvard, Vancouver, ISO, and other styles

5

Yang, Yi Huai, Li Fang Wang, and Yuan Li. "Propagation Channel Modeling for Rayleigh and Rice Fading." Applied Mechanics and Materials 687-691 (November 2014): 3648–51. http://dx.doi.org/10.4028/www.scientific.net/amm.687-691.3648.

Full text

Abstract:

An important requirement for assessing technology for wireless applications is to have an accurate description of the wireless channel. Rayleigh and Rice are the most popular models for wireless channels. In this paper, we simulation study the most important statistical properties, such as PDF and CDF, of Rayleigh and Rice channels, we also simulate the outputs of complex signals which passed the Rayleigh and Rice channels, and give some useful results.

APA, Harvard, Vancouver, ISO, and other styles

6

Gómez-Déniz, E., L. Gómez, and H. W. Gómez. "The Slashed-Rayleigh Fading Channel Distribution." Mathematical Problems in Engineering 2019 (February 11, 2019): 1–14. http://dx.doi.org/10.1155/2019/2719849.

Full text

Abstract:

We propose an alternative distribution for modelling fading-shadowing wireless channels. This distribution presents certain advantages over the Rayleigh-lognormal distribution and the K distribution and has proved useful in the setting described. We obtain closed-form expressions for the average channel capacity and for the average bit error rate of differential phase-shift keying and of minimum shift keying when the new distribution is used. This distribution can be obtained exactly as the sum of mutual independent Gaussian stochastic processes, because it must represent the simulation of the fading channel; that is, it simulates the signal envelope. Finally, we describe practical applications of this distribution, comparing it with the Rayleigh-lognormal and K distributions.

APA, Harvard, Vancouver, ISO, and other styles

7

Yu, Xiao Lei, Yin Shan Yu, Yu Yu Ji, and Dong Hua Wang. "Communication Performance of RFID System and Anti-Interference in the Multipath Rayleigh Fading Channel." Applied Mechanics and Materials 239-240 (December 2012): 1022–26. http://dx.doi.org/10.4028/www.scientific.net/amm.239-240.1022.

Full text

Abstract:

With the communication environment of RFID system developing from near field communication to long distance communication, Rayleigh fading with Doppler frequency shift emerges from multipath effect between the readers and electronic tags. A systemic study was focused on modeling and analysis of channel transmission for Type A tag signals in the multipath Rayleigh fading channel. Furthermore, the OFDM system was added to the RFID tag signals to improve the sensitivity of SNR in the Rayleigh fading channel. The SNR of tag signal is not sensitive in the multipath Rayleigh fading channel. However, the sensitivity increases after OFDM is added to the RFID system and the anti-interference ability is highly improved.

APA, Harvard, Vancouver, ISO, and other styles

8

Kang, Weimin. "A Nonbinary LDPC-Coded Probabilistic Shaping Scheme for a Rayleigh Fading Channel." Entropy 24, no. 11 (November 14, 2022): 1649. http://dx.doi.org/10.3390/e24111649.

Full text

Abstract:

In this paper, a novel, nonbinary (NB) LDPC-coded probabilistic shaping (PS) scheme for a Rayleigh fading channel is proposed. For the NB LDPC-coded PS scheme in Rayleigh fading channel, the rotation angle of 16 quadrature amplitude modulation (QAM) constellations, 64QAM constellations and 256QAM constellations are optimized by the exhaustive search. The simulation results verify the information–theoretical analysis. Compared with the binary LDPC-coded PS scheme for Rayleigh fading channel, the proposed NB LDPC-coded PS scheme can improve error performance. In summary, the proposed NB LDPC-coded PS scheme for Rayleigh fading channel is reliable and thus suitable for future communication systems.

APA, Harvard, Vancouver, ISO, and other styles

9

Aráuz, Julio, Prashant Krishnamurthy, and Miguel A. Labrador. "Discrete Rayleigh fading channel modeling." Wireless Communications and Mobile Computing 4, no. 4 (June 2004): 413–25. http://dx.doi.org/10.1002/wcm.185.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Gambe, Hirohisa, Kenji Yokoyama, Miyoshi Saito, and Kiyomichi Araki. "Channel parameter estimation in Rayleigh fading channel." Electronics and Communications in Japan (Part III: Fundamental Electronic Science) 88, no. 5 (2005): 1–11. http://dx.doi.org/10.1002/ecjc.20152.

Full text

APA, Harvard, Vancouver, ISO, and other styles

11

Noga, Krystyna, and Beata Pałczyńska. "Overview of Fading Channel Modeling." International Journal of Electronics and Telecommunications 56, no. 4 (November 1, 2010): 339–44. http://dx.doi.org/10.2478/v10177-010-0044-x.

Full text

Abstract:

Overview of Fading Channel ModelingVisSim and LabVIEW based approaches are proposed and implemented to demonstrate fading in the communication systems. The introduction to fading, models for flat fading like Rayleigh, Weibull, Nakagami-mand the results of simulations are presented.

APA, Harvard, Vancouver, ISO, and other styles

12

Grant, Alex. "Co-channel interference reduction in Rayleigh fading channels." Digital Signal Processing 16, no. 5 (September 2006): 619–27. http://dx.doi.org/10.1016/j.dsp.2004.10.005.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

González-Aurioles, Santiago, J. L. Padilla, P. Padilla, Juan F. Valenzuela-Valdés, and Juan C. Gonzalez-Macias. "On the MIMO Capacity for Distributed System under Composite Rayleigh/Rician Fading and Shadowing." International Journal of Antennas and Propagation 2015 (2015): 1–12. http://dx.doi.org/10.1155/2015/105017.

Full text

Abstract:

Wireless channels are commonly affected by short-term fading and long-term fading (shadowing). The shadowing effects must be taken into account also when mobility is present in the wireless scenario. Using a composite fading model, the total channel capacity can be studied for a scenario with short-term Rayleigh fading along with shadowing. This work provides quantitative results for these kinds of scenarios with Rayleigh fading and shadowing, considering also multiple-input and multiple-output systems, which have not been previously reported. In addition, the channel capacity has been studied in depth in its relation with the shadowing level, signal to noise ratio, and the number of elements in the multiple-input and multiple-output system. Moreover, the channel performance with shadowing has been compared to the one without it. Furthermore, Rician model with shadowing is studied and its results are reported. In addition, correlated and experimental results are provided. It is identified that the distributed MIMO systems can benefit from shadowing in Rician channels. This advantage has not been reported previously. This type of fading is proposed for massive MIMO by others and our results open the door to emulate massive MIMO on a reverberation chamber.

APA, Harvard, Vancouver, ISO, and other styles

14

Mitic, Dragan, Aleksandar Lebl, Branimir Trenkic, and Zarko Markov. "An overview and analysis of BER for three diversity techniques in wireless communication systems." Yugoslav Journal of Operations Research 25, no. 2 (2015): 251–69. http://dx.doi.org/10.2298/yjor131120007m.

Full text

Abstract:

Characteristics of a wireless communication channel are subjected to a large scale deterioration process, referred to as the problem of fading. This paper discusses different techniques for mitigating the fading problems. One solution to the problem is to add a fading margin on the transmitter, but it is not an effective solution. The other solution is to use an alternative statistical behavior of fading channels (applying the basic concepts of diversity), which use two or more inputs on the receiver to ensure the correlation of signal. So, the diversity technique is used to improve system performance in fading channels. Instead of transmitting and receiving the desired signal through one channel, we have L copies of desired signal transferred over M different channels. This paper presents analytical results of the probability of error for diversity techniques which use Rayleigh Fading Channel for BPSK modulation.

APA, Harvard, Vancouver, ISO, and other styles

15

Gómez-Déniz, Emilio, and Luis Gómez. "The Rayleigh Birnbaum Saunders Distribution: A General Fading Model." Symmetry 12, no. 3 (March 3, 2020): 389. http://dx.doi.org/10.3390/sym12030389.

Full text

Abstract:

A new compound non-symmetric distribution for modeling arbitrary fading-shadowing wireless channels is introduced and studied here. This distribution has some advantages in front of other well-known non-symmetric fading distributions such as the Rayleigh–lognormal distribution and the K distribution especially in the tails. We give closed-form expressions for the average BER of DPSK and MSK when the new distribution is used. Applications to compare how the new distribution works in comparisons with the Rayleigh–lognormal, K distributions and others recently proposed in the literature of fading channel are also provided.

APA, Harvard, Vancouver, ISO, and other styles

16

Daba, Jihad. "Stochastic Models for the Fading Channel Success Rate of Sub-6G UWB Systems." WSEAS TRANSACTIONS ON CIRCUITS AND SYSTEMS 21 (December 31, 2022): 223–30. http://dx.doi.org/10.37394/23201.2022.21.24.

Full text

Abstract:

This paper presents different stochastic models for entangled UWB fading channels. Closed-form canonical expressions are derived for the statistical distribution of the fading power difference of interfering independent and dependent mixture of flat-fading Rayleigh and Rician channels. The link success probability is derived in terms of the cumulative distribution function of the channel fading power differences. An alternative metric for link success rate (LSR) is developed in terms of the statistical distribution of the ratio of the diffuse powers. Under this alternative formulation, and for the case of 2 independent Rayleigh paths, the LSR statistical distribution was consistent with the heavy-tail Lomax distribution. The scope of future research includes the validation of theoretical and simulated models with real measurements on actual multi-user massive multiple-input-multiple-output (MU-mMIMO) beam-forming sub-6G physical systems.

APA, Harvard, Vancouver, ISO, and other styles

17

Gutiérrez, Carlos A., J. J. Jaime-Rodríguez, J. M. Luna-Rivera, Daniel U. Campos-Delgado, and Javier Vázquez Castillo. "Modeling of Non-WSSUS Double-Rayleigh Fading Channels for Vehicular Communications." Wireless Communications and Mobile Computing 2017 (2017): 1–15. http://dx.doi.org/10.1155/2017/6394653.

Full text

Abstract:

This paper deals with the modeling of nonstationary time-frequency (TF) dispersive multipath fading channels for vehicle-to-vehicle (V2V) communication systems. As a main contribution, the paper presents a novel geometry-based statistical channel model that facilitates the analysis of the nonstationarities of V2V fading channels arising at a small-scale level due to the time-varying nature of the propagation delays. This new geometrical channel model has been formulated following the principles of plane wave propagation (PWP) and assuming that the transmitted signal reaches the receiver antenna through double interactions with multiple interfering objects (IOs) randomly located in the propagation area. As a consequence of such interactions, the first-order statistics of the channel model’s envelope are shown to follow a worse-than-Rayleigh distribution; specifically, they follow a double-Rayleigh distribution. General expressions are derived for the envelope and phase distributions, four-dimensional (4D) TF correlation function (TF-CF), and TF-dependent delay and Doppler profiles of the proposed channel model. Such expressions are valid regardless of the underlying geometry of the propagation area. Furthermore, a closed-form solution of the 4D TF-CF is presented for the particular case of the geometrical two-ring scattering model. The obtained results provide new theoretical insights into the correlation and spectral properties of small-scale nonstationary V2V double-Rayleigh fading channels.

APA, Harvard, Vancouver, ISO, and other styles

18

Kumar B, Santhosh, and K. Ayyappa Swamy. "FPGA Implementation of a Nakagami-m fading channel Simulator using Random Number Generator." Indonesian Journal of Electrical Engineering and Computer Science 4, no. 1 (October 1, 2016): 133. http://dx.doi.org/10.11591/ijeecs.v4.i1.pp133-140.

Full text

Abstract:

By realizing the concept of implementation of the radio propagation channels on simulators is the eminent intention of this work. Even though prototyping software simulators are effortless to design we prefer hardware simulators as they endeavors distinguishable quickness, compared to earlier. Prior to this work fading channels like Gaussian, Rayleigh and Rician fading channel simulators were executed on hard ware.(i.e. FPGA) The significant target of this attempt is to implement Nakagami-m fading channel on hardware as they preserved for unsubstantial consideration. While differentiating with other fading channels Nakagami-m fading channel acquires wide spread applications, as its capability of providing appropriate fit for practical fading data, as this is flexible through its size parameter ‘m’, over which representation of signal fading conditions that vary from serious to modest, to normal fading or no fading is accomplished . The proposed hardware simulator can hatches complex Nakagami variates after it was implemented on XilinxSpartan-xc3s500e-4fg320 FPGA. This is operated at 50MHz.

APA, Harvard, Vancouver, ISO, and other styles

19

D'Andrea, Aldo N., Antonello Diglio, and Umberto Mengali. "Symbol-aided channel estimation with nonselective Rayleigh fading channels." IEEE Transactions on Vehicular Technology 44, no. 1 (February 1995): 41–49. http://dx.doi.org/10.1109/25.350268.

Full text

APA, Harvard, Vancouver, ISO, and other styles

20

Patil, Hemlata, Sai Vennela Nekkanti, Disha Negi, Nikita Masanagi, and Sakshi More. "Spectrum Sensing Using Energy Detector in Rayleigh Fading Channel." ITM Web of Conferences 32 (2020): 02005. http://dx.doi.org/10.1051/itmconf/20203202005.

Full text

Abstract:

Cognitive Radio, which is an adaptive and intelligent radio has an important feature called spectrum sensing. It monitors the presence or absence of the authorized users in a fixed or licensed spectrum. There is a rise in the use of wireless communications in recent times, which has led to the underutilization of the available bandwidth. This problem can be solved to some extent by using cognitive radio technology. Cognitive radio gives an opportunity for unauthorized users to use the licensed spectrum, resourcefully, when not in use. Using spectrum sensing energy detection methods, the existence of authorized users, in various fading channels can be done. The operating characteristics of the receiver can be analyzed using parameters of performance like signal to noise ratio, probability of false-alarm, probability of detection. In this paper we assess Rayleigh fading channel and compare with AWGN (non- fading) channel. Theoretical and simulated results are compared, and observations are being made.

APA, Harvard, Vancouver, ISO, and other styles

21

Kharchenko, Volodymir, Andrii Grekhov, Vasyl Kondratiuk, and Karina Nagorna. "ADS-B Satellite Communication Channel Based on IEEE 802.16 Standard." Transport and Aerospace Engineering 5, no. 1 (December 1, 2017): 18–27. http://dx.doi.org/10.1515/tae-2017-0014.

Full text

Abstract:

AbstractOriginal models of “Aircraft-Satellite-Ground Station” communication channel based on IEEE 802.16 standard were built by using MATLAB Simulink. The influence of aircraft transmitter nonlinearity for different types of fading in the channel (Rayleigh and Rician) was studied and the possibility of correcting nonlinearity by using pre-distortion was revealed. The impact of space-time diversity (MISO 2 × 1) for different types of fading in channels was investigated. The effect of the Doppler frequency shift on the operation of communication channels was analyzed.

APA, Harvard, Vancouver, ISO, and other styles

22

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.

Full text

Abstract:

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.

APA, Harvard, Vancouver, ISO, and other styles

23

Liu, Yuyu, Jinbao Zhang, and Dan Zhang. "Saddle Point Approximation of Mutual Information for Finite-Alphabet Inputs over Doubly Correlated MIMO Rayleigh Fading Channels." Applied Sciences 11, no. 10 (May 20, 2021): 4700. http://dx.doi.org/10.3390/app11104700.

Full text

Abstract:

Given the mutual information of finite-alphabet inputs cannot be calculated concisely and accurately over fading channels, this paper proposes a new method to calculate the mutual information. First, the applicability of the saddle point method is studied, and then the mutual information is estimated by the saddle point approximation method with known channel state information. Furthermore, we induce the expectation of mutual information over doubly correlated multiple-input multiple-output (MIMO) Rayleigh fading channels. The validity of the saddle point approximation method is verified by comparing the numerical results of the Monte Carlo method and the saddle point approximation method under different doubly correlated MIMO fading channel scenarios.

APA, Harvard, Vancouver, ISO, and other styles

24

Mandal, Nasiba, and Tapan P. Bagchi. "A New Analytical Approach to Estimate Fading in Mobile Communication System Design." Applied Mechanics and Materials 619 (August 2014): 322–26. http://dx.doi.org/10.4028/www.scientific.net/amm.619.322.

Full text

Abstract:

This paperprovides a novel analytical platform for evaluating theessential second order statistical boundaries for fading in mobile communication for average fade duration (AFD) and levelcrossing rate (LCR) of Rayleigh, Rician and Nakagami fading channels. We derive new expressions for average LCR and AFD. We then model and computationally simulate the proposed method for Rayleigh, Rician and Nakagami channels and separately calculate the LCR and AFD for each channel by this approach. Simulated results obtained for all three channels show that the values of LCR and AFD calculated by using the proposed approach are much closer to actual simulated values than what conventional theoretical formulas deliver.

APA, Harvard, Vancouver, ISO, and other styles

25

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.

Full text

Abstract:

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.

APA, Harvard, Vancouver, ISO, and other styles

26

Behruzifar, Amir, and Abolfazl Falahati. "Maximizing Outage Capacity in Rayleigh Fading Channel." International Journal of Computer Science and Artificial Intelligence 2, no. 1 (March 30, 2012): 15–17. http://dx.doi.org/10.5963/ijcsai0201003.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

Girand, X., and J. C. Belfiore. "Constellations matched to the Rayleigh fading channel." IEEE Transactions on Information Theory 42, no. 1 (1996): 106–15. http://dx.doi.org/10.1109/18.481782.

Full text

APA, Harvard, Vancouver, ISO, and other styles

28

Bravo-Santos, Angel. "Polar Codes for the Rayleigh Fading Channel." IEEE Communications Letters 17, no. 12 (December 2013): 2352–55. http://dx.doi.org/10.1109/lcomm.2013.111113.132103.

Full text

APA, Harvard, Vancouver, ISO, and other styles

29

Li, Ying, Yi Jun Zhu, Lan Ma, and Yao Zhu. "On the Capacity of MIMO Channels with Outdated Channel State Information." Advanced Materials Research 204-210 (February 2011): 2053–56. http://dx.doi.org/10.4028/www.scientific.net/amr.204-210.2053.

Full text

Abstract:

A Multiple-input multiple-output (MIMO) time-varying flat fading channel is considered. The transmitter obtained the channel state information (CSI) relying on the reciprocity principle or by the feedback from the receiver. Thus, channel state information at the transmitter (CSIT) is outdated due to the delay between the estimation of the channel and the transmission of the data. In order to achieve the maximum channel capacity, the transmitter linearly precoded the signal before transmission based on the outdated CSIT. Under the assumptions of wide-sense stationary uncorrelated scattering Rayleigh fading channels and Jake’s model, the instantaneous mutual information and ergodic capacity is derived for MIMO channels with outdated CSIT. The information outage probability of MIMO channel with outdated CSIT is also presented.

APA, Harvard, Vancouver, ISO, and other styles

30

Zhang, Gang, Chuan gang Wang, Guo quan Li, and Jin zhao Lin. "Design and Performance Analysis of MISO-ORM-DCSK System over Rayleigh Fading Channels." International Journal of Antennas and Propagation 2016 (2016): 1–8. http://dx.doi.org/10.1155/2016/8459109.

Full text

Abstract:

A novel chaotic communication system, named Orthogonality-based Reference Modulated-Differential Chaos Shift Keying (ORM-DCSK), is proposed to enhance the performance of RM-DCSK. By designing an orthogonal chaotic generator (OCG), the intrasignal interference components in RM-DCSK are eliminated. Also, the signal frame format is expanded so the average bit energy is reduced. As a result, the proposed system has less interference in decision variables. Furthermore, to investigate the bit error rate (BER) performance over Rayleigh fading channels, the MISO-ORM-DCSK is studied. The BER expressions of the new system are derived and analyzed over AWGN channel and multipath Rayleigh fading channel. All simulation results not only show that the proposed system can obtain significant improvement but also verify the analysis in theory.

APA, Harvard, Vancouver, ISO, and other styles

31

Dvornikov, Sergey V., Evgeniy V. Markov, and Adjan A. Manoshi. "NCREASING IMMUNITY OF DECAMETER RADIO CHANNEL TRANSMISSIONS UNDER UNINTENDED INTERFERENCE." T-Comm 15, no. 6 (2021): 4–9. http://dx.doi.org/10.36724/2072-8735-2021-15-6-4-9.

Full text

Abstract:

The transmission of messages is a complex process, which is largely determined by the properties of the radio channel used. Decameter radio channels are the most difficult for organizing communication, since the ionospheric propagation of radio waves is associated with their significant attenuation, due to the significant length of the paths, as well as the presence of Rayleigh fading in the channel. However, the possibility of transmitting information over long distances without serious resource costs stimulates further research to improve the reliability of decameter radio communication. In this paper, we investigate the possibility of increasing the noise immunity of frequency-shift keying transmissions of decameter radio channels in conditions of unintentional interference due to the use of broadband signals. An analytical expression of the dependence of the probability of a bit error on the level of the ratio of the peak signal power to the peak interference power is considered; a graph of this dependence is presented. It is shown that the plot is consistent with the overall noise immunity estimate for Rayleigh fading channels using double FSK signals. The rationality of methods for obtaining the required reception quality in decameter radio channels is analyzed. It is shown that the most rational direction for increasing the noise immunity of FM-2 transmissions in decameter radio channels with Rayleigh fading in conditions of unintended interference is the use of broadband signals. In this case, for expansion, it is advisable to choose a value kf = 7, which makes it possible to increase the noise immunity by 9 dB. The conclusions are illustrated by graphs.

APA, Harvard, Vancouver, ISO, and other styles

32

F. Mohammed, Hassan, and Ghanim A. Al-Rubaye. "BER PERFORMANCE ANALYSIS OF 4QAM/OFDM OVER DIFFERENT SCENARIOS OF LAPLACE FADING CHANNEL." Journal of Engineering and Sustainable Development 25, Special (September 20, 2021): 1–26. http://dx.doi.org/10.31272/jeasd.conf.2.1.4.

Full text

Abstract:

Multicarrier transmission, also known as (OFDM) Orthogonal Frequency Division multiplexing, in wireless communications, it has been proven to be an essential technique for countering multipath fading. It has been used successfully for HF radio applications and has been selected as the interface for digital audio transmission, digital terrestrial TV broadcasting, and high-speed wireless local area networks in Europe. In this paper, we suggested a new design for modeling multipath fading channels, such as the Laplace fading channel, in order to discover new simulation results and effects. Furthermore, the variance of the Laplace fading channel has been computed and the new Bit Error Rate (BER) derivation is established, and the performance of (M-QAM), M-ary Quadrature Amplitude Modulation (with M=4 over OFDM system under Laplace fading channels in Additive White Gaussian Noise (AWGN) is discussed and compared to the conventional M-QAM/OFDM system Rayleigh fading channel in AWGN. All the simulation results are examined using the optimum signal detection based on the Euclidean distance and evaluated using Monte-Carlo simulation.

APA, Harvard, Vancouver, ISO, and other styles

33

Wonjin Sung and In-Kyung Kim. "An MLSE receiver using channel classification for Rayleigh fading channels." IEEE Journal on Selected Areas in Communications 18, no. 11 (November 2000): 2336–44. http://dx.doi.org/10.1109/49.895038.

Full text

APA, Harvard, Vancouver, ISO, and other styles

34

Hoang Son, Vu Tran, and Dang Le Khoa. "BER Analysis for Downlink MIMO-NOMA Systems over Rayleigh Fading Channels." International journal of Computer Networks & Communications 13, no. 6 (September 30, 2021): 93–108. http://dx.doi.org/10.5121/ijcnc.2021.13606.

Full text

Abstract:

The Multiple-input multiple-output (MIMO) technique combined with non-orthogonal multiple access (NOMA) has been considered to enhance total system performance. This paper studies the bit error rate of two-user power-domain NOMA systems using successive interference cancellation receivers, with zeroforcing equalization over quasi-static Rayleigh fading channels. Successive interference cancellation technique at NOMA receivers has been the popular research topic due to its simple implementation, despite its vulnerability to error propagation. Closed-form expressions are derived for downlink NOMA in single-input single-output and uncorrelated quasi-static MIMO Rayleigh fading channel. Analytical results are consolidated with Monte Carlo simulation.

APA, Harvard, Vancouver, ISO, and other styles

35

Biazaran, Reza, and Hermann Joseph Helgert. "Improved noisy gradient descent bit-flipping algorithm over Rayleigh fading channel." International Journal of Electrical and Computer Engineering (IJECE) 12, no. 3 (June 1, 2022): 2699. http://dx.doi.org/10.11591/ijece.v12i3.pp2699-2710.

Full text

Abstract:

Gradient descent bit flipping (GDBF) and its many variants have offered remarkable improvements over legacy, or modified, bit flipping decoding techniques in case of decoding low density parity check (LDPC) codes. GDBF method and its many variants, such as noisy gradient descent bit flipping (NGDBF) have been extensively studied and their performances have been assessed over multiple channels such as binary symmetric channel (BSC), binary erasure channel (BEC) and additive white Gaussian noise (AWGN) channel. However, performance of the said decoders in more realistic channels or channel conditions have not been equally studied. An improved noisy gradient descent bit flipping algorithm is proposed in this paper that optimally decodes LDPC encoded codewords over Rayleigh fading channel and under various fade rates. Comparing to NGDBF method, our proposed decoder provides substantial improvements in both error performance of the code, and in the number of iterations required to achieve the said error performance. It subsequently reduces the end-to-end latency in applications with low or ultra-low latency requirements.

APA, Harvard, Vancouver, ISO, and other styles

36

Cuu, Ho Van, Hoang Hiep Le, and Nguyen Thi Thu-Hang. "EFFICIENT ANALYSIS OF MIMO-OFDM SYSTEM IN NAKAGAMI-m FADING CHANNEL." Vietnam Journal of Science and Technology 54, no. 6 (December 7, 2016): 698. http://dx.doi.org/10.15625/0866-708x/54/6/8311.

Full text

Abstract:

Bit error rate (BER) and symbol error rate (SER) performance response fading parameter for multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) system over Nakagami-m fading channel would be provided in this study. Some channel simulations and evaluations were for 2×2 MIMO-OFDM system in which data are sent from two transmit antennas to two receive antennas. In this study, authors have used binary phase-shift keying (BPSK) and quadrature phase-shift keying (QPSK) modulation techniques to modulate the data stream. In addition, numerical results have been presented and compared for several different environmental propagations such as Nakagami-m, Rician, Rayleigh multipath fading channels, and non-fading additive white Gaussian noise (AWGN) channel. Based on such obtained presentation and comparison, the paper would discuss further about relation between value of paramater m and quality of system.

APA, Harvard, Vancouver, ISO, and other styles

37

Kuo, Po Yu, and Gan Zhi Fan. "Analysis and Implementation of Rayleigh Fading Channel Using MATLAB." Applied Mechanics and Materials 764-765 (May 2015): 476–80. http://dx.doi.org/10.4028/www.scientific.net/amm.764-765.476.

Full text

Abstract:

Mobile wireless communication is the fastest growing segment of the communication industry. However, it is faced with the challenge of providing reliable high-speed communications due to channel impediments which change over time in unpredictable ways. To analyze the reliability and performance of real communication system, the Rayleigh fading channel is generally applied to simulate the real wireless communication. In this paper, we analyze and implement a flat Rayleigh fading channel based on the inverse discrete Fourier transform (IDFT). The simulation results of level crossing rate (LCR) and average fade duration (AFD) are shown in this paper.

APA, Harvard, Vancouver, ISO, and other styles

38

Xie, Bo, Congfang Ma, Haiqiong Li, Gaoyuan Zhang, and Congzheng Han. "Simple and Robust Log-Likelihood Ratio Calculation of Coded MPSK Signals in Wireless Sensor Networks for Healthcare." Applied Sciences 12, no. 5 (February 23, 2022): 2330. http://dx.doi.org/10.3390/app12052330.

Full text

Abstract:

The simple and robust log-likelihood ratio (LLR) computation of coded Multiple Phase Shift Keying (MPSK) signals in Wireless Sensor Networks (WSNs) is considered under both phase noncoherent and Rayleigh fading channels for healthcare applications. We first simplify the optimal LLR for phase noncoherent channel, the estimation of the instantaneous channel state information (CSI) for both the fading amplitude and the additive white Gaussian noise (AWGN) is successfully avoided, and the complexity-intensive process for zero-order Bessel function of the first kind is also perfectly eliminated. Furthermore, we also develop the simplified LLR under Rayleigh fading channel. Correspondingly, the variance estimation for both AWGN and the statistical characteristic of the fading amplitude is no longer required, and the complicated process for implementation of the exponential function is also successfully avoided. Compared to the calculation of optimal LLR with full complexity, the proposed method is implementation-friendly, which is practically desired for energy-limited WSNs. The simulations are developed in the context of low-density parity-check (LDPC) codes, and the corresponding results show that the detection performance is extremely close to that of the full-complexity LLR metrics. That is, the performance degradation is efficiently prevented, whereas complexity reduction is also successfully achieved.

APA, Harvard, Vancouver, ISO, and other styles

39

Akbari, Mohsen, Mohsen Riahi Manesh, Ayman A. El-Saleh, and Ahmed Wasif Reza. "Receiver Diversity Combining Using Evolutionary Algorithms in Rayleigh Fading Channel." Scientific World Journal 2014 (2014): 1–11. http://dx.doi.org/10.1155/2014/128195.

Full text

Abstract:

In diversity combining at the receiver, the output signal-to-noise ratio (SNR) is often maximized by using the maximal ratio combining (MRC) provided that the channel is perfectly estimated at the receiver. However, channel estimation is rarely perfect in practice, which results in deteriorating the system performance. In this paper, an imperialistic competitive algorithm (ICA) is proposed and compared with two other evolutionary based algorithms, namely, particle swarm optimization (PSO) and genetic algorithm (GA), for diversity combining of signals travelling across the imperfect channels. The proposed algorithm adjusts the combiner weights of the received signal components in such a way that maximizes the SNR and minimizes the bit error rate (BER). The results indicate that the proposed method eliminates the need of channel estimation and can outperform the conventional diversity combining methods.

APA, Harvard, Vancouver, ISO, and other styles

40

Uddin, Jia, Mohammed Faisal, Md Facihul Azam, and A. F. M. Muzahidur Rahman. "Performance Analysis of Multicarrier Code Division Multiple Access over Rayleigh Fading Channel." Advanced Materials Research 457-458 (January 2012): 985–88. http://dx.doi.org/10.4028/www.scientific.net/amr.457-458.985.

Full text

Abstract:

Recently, multi-carrier transmission schemes have been introduced into Code Division Multiple Access (CDMA) systems to gain advantages for high data rate transmission as well as security. Due to pseudorandom code there is no chance to Inter Symbol Interference (ISI). There are different techniques to mitigate multipath fading. One of the method is to transmit identical narrowband direct-sequence (DS) waveforms in parallel over a number of sub-channels using frequency diversity. Implementation this multi-carrier modulation technique in CDMA system is known as multi-carrier CDMA (MC-CDMA). In Rayleigh fading channel, due to multi-carrier modulation, when one subcarrier goes deep fade another subcarrier may remain safe. Therefore it combats multi-path fading and signal can be received in low bit error rate.

APA, Harvard, Vancouver, ISO, and other styles

41

N. Thakre, Prasheel, Sanjay Pokle, Radhika Deshpande, Samruddhi Paraskar, Shashwat Sinha, and Yash Lalwani. "Performance analysis of NOMA in Rayleigh and Nakagami Fading channel." 3C TIC: Cuadernos de desarrollo aplicados a las TIC 11, no. 2 (December 29, 2022): 183–93. http://dx.doi.org/10.17993/3ctic.2022.112.183-193.

Full text

Abstract:

Cellular connectivity is expanding rapidly in the modern world. The multiple access strategy is one of the highly used methods for allocating the range of users in cellular network. Spectrum allocation is a crucial element to take into account since cellular communication is becoming more and more popular. NOMA is a channel access mechanism used in 5G mobile communication. It is also known as non-orthogonal multiple access. NOMA is a potential strategy for enhancing spectral efficiency and sum rate. Using the NOMA method, we evaluated the BER versus transmitted power of two users in rayleigh and nakagami fading channels. In this NOMA setup, a single antenna is shared by two users. Two users can accept the same frequency using 5G NOMA technology, but at different power levels. The results of the MATLAB simulation show that the two user NOMA in the Nakagami channel performs better than the Rayleigh channel in terms of Bit Error Rate vs. Transmitted Power.

APA, Harvard, Vancouver, ISO, and other styles

42

Zheng, Jian Yun, Li Li, and Yi Sheng Zhu. "The Performance of Double-Binary Turbo Codes in the HAP-Based Communication System." Applied Mechanics and Materials 713-715 (January 2015): 1141–44. http://dx.doi.org/10.4028/www.scientific.net/amm.713-715.1141.

Full text

Abstract:

The small-scale fading model for HAP-based communication channel is analyzed, the structure and algorithm of double-binary Turbo encoding and decoding are studied. Numerical results show the BER performance with different interleaving depth and interleaving length of double-binary Turbo codes using QPSK modulation over Rayleigh fading channel.

APA, Harvard, Vancouver, ISO, and other styles

43

Swarts, F., H. C. Ferreira, and D. R. Oosthuizen. "Renewal channel models for PSK on slowly fading Rayleigh channel." Electronics Letters 25, no. 22 (1989): 1514. http://dx.doi.org/10.1049/el:19891016.

Full text

APA, Harvard, Vancouver, ISO, and other styles

44

Hayajneh, Mohammad Suleiman, and Chaouki Abdallah. "Game Theoretic Distributed Power Control Algorithms for Uplink Wireless Data in Flat Fading Channels." International Journal of Computers Communications & Control 10, no. 4 (June 23, 2015): 520. http://dx.doi.org/10.15837/ijccc.2015.4.380.

Full text

Abstract:

In this paper we present a game-theoretic power control algorithms for wireless data in CDMA cellular systems under two realistic channels: (a1) Fast flat fading channel and (a2) Slow flat fading channel. The fading coefficients under both (a1) and (a2) are studied for three appropriate small scale channel models that are used in the CDMA cellular systems: Rayleigh channel, Rician channel and Nakagami channel. This work is inspired by the results presented by [1] under nonfading channels. In other words, we study the impact of the realistic channel models on the findings in [1] through the followings: we evaluate the average utility function, the average number of bits received correctly at the receiver per one Joule expended, for each channel model. Then, using the average utility function we study the existence, uniqueness of Nash equilibrium (NE) if it exists, and the social desirability of NE in the Pareto sense. Results show that in a non-cooperative game (NPG) the best policy for all users in the cell is to target a fixed signal-to-interference and noise ratio (SINR) similar to what was shown in [1] for non-fading channel. The difference however is that the target SINR in fading channels is much higher than that in a non-fading channel. Also, for spreading gain less than or equal to 100, both NPG and non-cooperative power control game with pricing (NPGP) perform poorly, where all the terminals except the nearest one were not able to attain their corresponding minimum SINR even if sending at the maximum powers in their strategy spaces.

APA, Harvard, Vancouver, ISO, and other styles

45

Liao, Run-Fa, Hong Wen, Jinsong Wu, Huanhuan Song, Fei Pan, and Lian Dong. "The Rayleigh Fading Channel Prediction via Deep Learning." Wireless Communications and Mobile Computing 2018 (July 25, 2018): 1–11. http://dx.doi.org/10.1155/2018/6497340.

Full text

Abstract:

This paper presents a multi-time channel prediction system based on backpropagation (BP) neural network with multi-hidden layers, which can predict channel information effectively and benefit for massive MIMO performance, power control, and artificial noise physical layer security scheme design. Meanwhile, an early stopping strategy to avoid the overfitting of BP neural network is introduced. By comparing the predicted normalized mean square error (NMSE), the simulation results show that the performances of the proposed scheme are extremely improved. Moreover, a sparse channel sample construction method is proposed, which saves system resources effectively without weakening performances.

APA, Harvard, Vancouver, ISO, and other styles

46

Costa, Lucas, Dayan Guimarães, Rausley de Souza, and Roberto Bomfin. "Cooperative Spectrum Sensing with Coded and Uncoded Decision Fusion under Correlated Shadowed Fading Report Channels." Sensors 19, no. 1 (December 23, 2018): 51. http://dx.doi.org/10.3390/s19010051.

Full text

Abstract:

This article addresses the impact of forward error correction when applied to the report channel transmissions of a centralized decision fusion cooperative spectrum sensing scheme designed to detect idle orthogonal frequency division multiple access (OFDMA) subchannels. The OFDMA signal is transmitted over slow frequency-selective multipath Rayleigh fading channels and sensed using the maximum eigenvalue detection test statistic. The decisions on the OFDMA subchannel occupancy are transmitted to a fusion center over report channels represented by a shadowed fading model combining a three-dimensional spatially correlated shadowing with a slow and flat multipath Rayleigh fading. Binary Bose-Chaudhuri-Hochquenghem (BCH) and Repetition codes are used to protect these decisions. Results show that shadowing correlation severely deteriorates the overall spectrum sensing performance and that error correction may not be able to protect the report channel transmissions. It can be even worse with respect to the system performance especially at low signal-to-noise regimes. In the situations in which error correction is effective, the Repetition code is capable of outperforming the BCH, meaning that the diversity gain may be more relevant than the coding gain when the spectrum sensing decisions are subjected to correlated shadowing.

APA, Harvard, Vancouver, ISO, and other styles

47

Khairol Fauz, Muhammad Zarol Fitri, and Elsheikh Mohamed Ahmed Elsheikh. "AWGN and Rayleigh Fading Behavior of the Wireless Decode-and-Forward Relay Channel with Arbitrary Time and Power Allocation." Indonesian Journal of Electrical Engineering and Computer Science 10, no. 1 (April 1, 2018): 248. http://dx.doi.org/10.11591/ijeecs.v10.i1.pp248-257.

Full text

Abstract:

Relying has in use for decades to tackle some of the challenges of wireless communication such as extending transmitting distance, transmitting over rough terrains. Diversity achieved through relaying is also a means to combat the random behavior of fading channels. In this work, effect of time and power allocation on relay performance is studied. The channel considered is the three-node channel with half-duplex constraint on the relay. The relaying technique assumed is decode-and-forward. Mutual information is used as the criteria to measure channel performance. There is half-duplex constraint and a total transmission power constraint on the relay source node and the relay node. A model is established to analyze the mutual information as a function of time allocation and power allocation in the case of AWGN regime. The model is extended to the Rayleigh fading scenario. In both AWGN and Rayleigh fading, results showed that the importance of relaying is more apparent when more resources are allocated to the relay. It was also shown that quality of the source to destination link has direct impact on the decision to relay or not to relay. Relatively good source to destination channel makes relaying less useful. The opposite is true for the other two links, namely the source to relay channel and the relay to destination channel. When these two channels are good, relaying becomes advantageous. When applied to cellular systems, we concluded that relaying is more beneficial to battery-operated mobile nodes than to base stations.

APA, Harvard, Vancouver, ISO, and other styles

48

Zhou, Dekun, Kai Niu, and Chao Dong. "Construction of Polar Codes in Rayleigh Fading Channel." IEEE Communications Letters 23, no. 3 (March 2019): 402–5. http://dx.doi.org/10.1109/lcomm.2019.2892453.

Full text

APA, Harvard, Vancouver, ISO, and other styles

49

Lee, W. C. Y. "Estimate of channel capacity in Rayleigh fading environment." IEEE Transactions on Vehicular Technology 39, no. 3 (1990): 187–89. http://dx.doi.org/10.1109/25.130999.

Full text

APA, Harvard, Vancouver, ISO, and other styles

50

Cui, Hao, Chong Luo, Chang Wen Chen, and Feng Wu. "Robust Linear Video Transmission Over Rayleigh Fading Channel." IEEE Transactions on Communications 62, no. 8 (August 2014): 2790–801. http://dx.doi.org/10.1109/tcomm.2014.2332502.

Full text

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Rayleigh fading channel'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles