• The KIPS Transactions:PartA
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• v.9A no.3
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• pp.295-300
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• 2002

In this paper, we apply the 3-dimension algorithm to the random interleaver and s-random interleaver and analyze the performance of the turbo code system with random interleaver (or s-random interleaver). In general, the performance of interleaver is determined by minimum distance between neighbor data, thus we could improve the performance of interleaver by increasing the distance of the nearest data. The interleaver using 3-dimension algorithm has longer minimum distance and average distance compared to existing random-interleaver (s-random interleaver) because the output data is generated randomly from 3-dimension storage. To verify and compare the performance of our proposed system, the computer simulations have been performed in turbo code system under gaussian noise environment.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.788-791
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• 2005

In this paper, We propose performance of improvement method for eHDR-WPAN system using Interleaver. Burst error pattern caused by fading in indoor wireless channel. for the reason, using of Interleave method (make burst error to random error) can be enhance to error-rate in system. This paper is used Convolutional, Block, Random Interleaver. We make use of 9 and 27 for symbol spacing. Block-Interleaver is show that performance about 0.6dB of E$_b$/N$_o$ at $10^{-4}$. In result, the suitable Interleaver for eHDR-WPAN system is Block Interleaver of 9 symbol spacing.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.12C
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• pp.1129-1134
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• 2006

In this paper, we analyze the cycle structure of punctured finite-length RA-type LDPC codes and design interleavers which have good memory efficiency and avoid short cycles. Furthermore, we introduce the check-node merging scheme for punctured finite-length RA-type LDPC codes and design simple interleavers. Simulation results show that punctured finite-length RA-type LDPC codes using the proposed simple interleavers have better performance than those with random and S-random interleavers.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.39 no.4
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• pp.165-172
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• 2002

In the next generation mobile communications, powerful channel coding is essential in order to obtain high quality multimedia services. Turbo code can achieve good error performance by iterative decoding, but more iterations result in additional computational complexity and delay. Thus, a method to reduce the number of iterations without additional performance degradation is needed. Turbo code with CRC is known to be the most efficient method to reduce the number of iterations. In this scheme, the performance may be degraded by the edge-effect like the conventional turbo code without CRC. In this paper, a method to eliminate the edge-effect is proposed by adopting D-parameter to the conventional s-random interleaver. As results of simulation, the edge-effect of the turbo code with CRC is shown to be successfully eliminated by using the new interleaver designed with D-parameter.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.3A
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• pp.173-179
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• 2002

In this paper, we suggest more precise performance analysis method of turbo interleavers based on two criteria; performance bounds like Union Bound and weight frequency of codewords. In order to present our new method, we employ block pseudo random, and so-called prime interleavers in compliance of 3GPP standard, respectively, We also applied this method to S-random interleavers that have different window size, S. 3GPP complied turbo encoder, decoder, and AWGN channel are implemented by using MATLAB for our performance analysis. According to our analysis, both criteria should be taken into account coincidently to predict the performance of newly designed interleavers.

• The Journal of the Acoustical Society of Korea
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• v.27 no.6
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• pp.286-295
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• 2008

Underwater acoustic communication has multi path error because of reflection by sea-level and sea-bottom. The multipath of underwater channel causes signal distortion and error floor. In this paper, we consider the use of various channel coding schemes such as RS code, convolutional code, cross-layer code and LDPC code in order to compensate the multipath effect in underwater channel. As shown in simulation results, characteristic of multipath error is similar to that of random error, so interleaver has little effect for error correcting. For correcting of error floor by multipath error, it is necessary strong channel codes like LDPC code that is similar to Shannon's limit. And the performance of concatenated codes including RS codes has better performance than using singular channel codes.