• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.7
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• pp.3156-3167
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• 2020

One drawback of polar codes is that they are not universal, that is, to achieve optimal performance, different polar codes are required for different kinds of channel. This paper proposes a polar code construction scheme for Nakagami-m fading channel. The scheme fully considers the characteristics of Nakagami-m fading channel, and uses the optimized Bhattacharyya parameter bounds. The constructed code is applied to an orthogonal frequency division multiplexing (OFDM) system over Nakagami-m fading channel to prove the performance of polar code. Simulation result shows the proposed codes can get excellent bit error rate (BER) performance with successive cancellation list (SCL) decoding. For example, the designed polar code with cyclic redundancy check (CRC) aided SCL (L = 8) decoding achieves 1.1dB of gain over LDPC at average BER about 10^-5 under 4-quadrature amplitude modulation (4QAM) while the code length is 1024, rate is 0.5.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.10 no.7
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• pp.1074-1084
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• 1999

In this paper the bit error probability of noncoherent M-ary FSK system is derived from the probability density function of the envelope of the received signal over a frequency-nonselective slowly m-distributed Nakagami fading channel. Also, the performance of coherent M-ray FSK system is theoretically analyzed, using union bound over the similar fading channel. Then we compare uncoded performance results for M-ary FSK and DPSK signals in Nakagami fading channel.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.1
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• pp.41-48
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• 2004

In this paper, we analyzed channel performance of PPM modulated UWB communication system in indoor radio fading environment that consider amplitude characteristic of channel. Fading channel considered various channel environments by fading index m utilizing Nakagami-m distribution model with data through an UBW radio signal experiment that announced in existing. Also, we improved performance of system that it is decreased in fading environment employing convolution encoding techniques.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.11
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• pp.4469-4482
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• 2015

In this paper, we investigate the outage performance of a two-way decode-and-forward relaying network in an interference-limited Nakagami-m fading environment. More specifically, assuming the presence of Nakagami-m faded multiple co-channel interferers at the source/destination terminals, the closed-form approximate expression for the outage probability is derived by using moment-based estimators attaining the appropriate Nakagami-m fading parameter. Simulation results demonstrate that our analytical result is in excellent agreement with the Monte Carlo simulation.

• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.94-97
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• 1998

In this paper we derive the pdf for the envelope of the received signal in Nakagami fading environment. Then, using this pdf we analyze the performance of Noncoherent FSK and DPSK in Nakagami fading channel. For ASK it is difficult to find the threshold value in Nakagami fading we confine our discussion in the special case of m=1, which is in Rayleigh fading.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.5
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• pp.1010-1019
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• 2004

In this paper, we represent Nakagami-m fading channel as finite-State Markov Channel (FSMC) and analyze the performance of wireless communication system with varying the fading channel condition. In FSMC model, the received signal's SNR is divided into finite intervals and these intervals are formed into Markov chain states. Each state is modeled by a BSC and the transition probability is dependent upon the physical characterization of the channel. The steady state probability and average symbol error rate of each state and transition probability are derived by numerical analysis and FSMC model is formed with these values. We found that various fading channels can be represented with FSMC by changing state transition index. In fast fading environment in which state transition index is large, the channel can be viewed as i.i.d. channel and on the contrary, in slow fading channel where state transition index is small, the channel can be represented by simple FSMC model in which transitions occur between just adjacent states. And we applied the proposed FSMC model to analyze the coding gain of random error correcting code on various fading channels via computer simulation.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.34S no.11
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• pp.9-15
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• 1997

The Nakagami m-distribution is used to model different fading environments and shown to fit experimental resutls more accurately than other distributions. In this paper, the probability of symbol error for M-ary QAM with square signal constellation in frequency-nonselective shlow Nakagami fading and additive white Gaussian noise is derived. When Nakagami fading index is integer, the derived resutls leads to the closed-form of a finite series.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.1
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• pp.9-18
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• 2003

In this paper, we analyzed the throughput of DS/CDMA system applying packet combining scheme combined with Type- I Hybrid ARQ scheme over AWGN channel and Nakagami fading channel with RAKE receiver. As the parameter for analysis, we used number of combined packet(L), number of diversity branch$({L_c})$, fading index(m), and length of packet(N), and used CRC-12 error detection code and (2,1,3) convolutional code. As a results, we found that throughput of system over Nakagami fading channel with RAKE receiver was superior to throughput over AWGN channel, and throughput of system decreases rapidly as channel degrades when number of combined packet(L) was increased. However throughput of system with the combining scheme was achieved even at low ${E_b}/{N_o}$. Also, we found that throughput of system was increased when fading index(m) and number of diversity branch$({L_c})$ were increased, but it was decreased when number of user(K) and length of packet(N) were increased.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.8C
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• pp.754-761
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• 2005

We derive and analyze a bit error rate(BER) expression of a Gray coded rectangular QAM(R-QAM) signal with maximal ratio combining diversity(MRC) reception over Nakagami-n(Rician) fading channels. The derived result is provided in terms of the Whittaker function and the confluent hypergeometric function. In addition, by performance comparison with M-PSK, we see the Nakagami-n fading channel characteristics. Because the derived expression is general, it can readily allow numerical e·valuation for various cases of practical interest such as line-of-sight (LOS) or satellite communication channel analysis.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.6 no.8
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• pp.1161-1168
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• 2002

In this paper, the throughput performance of an ARQ scheme is analyzed with noisy feedback channel, in order to exactly analysis for performance of an ARQ scheme. An ARQ mechanism is presented by state diagram, and the throughput of an ARQ scheme is mathematically derived using generation function for a signal flow graph. The channel is modeled by the Nakagami-m fading channel which is distributed over far and wide, and the throughput performance of an ARQ scheme, which is applied in BPSK and BFSK systems, according to feedback gain and fading index m is analyzed through computer simulation. In the results, It is shown conformed that the throughput of an ARQ scheme decreased according to the increase of the noise for feedback channel, but it increased according to the increase of the feedback gain and fading index m. Also, it is shown that the throughput of an ARQ scheme using BPSK system is superior to BFSK system because of the difference of bit error probability between BPSK and BFSK systems.