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Coded modulations for mobile satellite communication channels.

机译：移动卫星通信信道的编码调制。

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摘要

The mobile satellite (MSAT) channel is subject to multipath fading, shadowing, Doppler frequency shift, and adjacent channel interference (ACI). Therefore, transmitted signals face severe amplitude and phase distortions.;This dissertation investigates various high performance and low decoding complexity coded modulation schemes for reliable voice and data transmissions over the shadowed mobile satellite channel and the Rayleigh fading channel. The dissertation consists of four parts. The first part presents a systematic technique for constructing MPSK trellis coded modulation (TCM) codes for voice transmission over the MSAT channel. The multilevel coding method is used for constructing TCM codes using convolutional codes with good free branch distances as the component codes or using both convolutional and block codes as the component codes. Simulation results show that these codes achieve good coding gains over the uncoded reference system and outperform existing TCM codes with the same decoding complexity.;In the second part, using the multilevel coding method, multilevel block coded modulation (BCM) codes are constructed for voice transmission over the MSAT channel. Even though BCM is generally less power efficient than TCM for AWGN channels, BCM has a great potential to compete with TCM in the MSAT channel because of its shorter decoding depth and hence more effective interleaving. Binary Reed-Muller (RM) codes of length up to 32 are used as component codes. Simulation results show that these codes achieve good coding gains over the uncoded reference system and outperform TCM codes with the same decoding complexity.;In the third part, a simple and systematic technique for constructing multilevel concatenated BCM schemes for data transmission over the shadowed MSAT channel and the Rayleigh fading channel is presented. These schemes are designed to achieve high-performance or large coding gain with reduced decoding complexity. Construction is based on a multilevel concatenation approach in which long powerful (binary or non-binary) codes are used as the outer codes and coset codes constructed from a linear BCM code and its subcodes are used as the inner codes. Simulation results show that these codes achieve large coding gains over the uncoded reference system and outperform single-level concatenated BCM codes with the same inner codes. Especially, some multilevel concatenated BCM codes achieve an error-floor free communication at BER of 10;In the final part of the dissertation, product coded modulation schemes are constructed by using multilevel concatenating approach. In product coded modulation, the product coding technique and coded modulation are combined to achieve high performance with reduced decoding complexity. Good product 8-PSK modulation codes are constructed for various shadowed MSAT channels. Simulation results show that these codes achieve large coding gains over the uncoded reference system and outperform single-level concatenated BCM codes with the same inner codes.
机译：移动卫星（MSAT）信道会受到多径衰落，阴影，多普勒频移和相邻信道干扰（ACI）的影响。因此，发射信号面临严重的幅度和相位失真。本论文研究了各种高性能和低解码复杂度的编码调制方案，以在阴影移动卫星信道和瑞利衰落信道上进行可靠的语音和数据传输。本文共分四个部分。第一部分介绍了用于构建MPSK网格编码调制（TCM）代码以通过MSAT信道进行语音传输的系统技术。多级编码方法用于使用具有良好自由分支距离的卷积码作为分量码或使用卷积码和块码两者作为分量码来构造TCM码。仿真结果表明，这些代码在未编码的参考系统上具有良好的编码增益，并且在相同的解码复杂度上优于现有的TCM代码。第二部分，利用多级编码方法，为语音构造了多级分组编码调制（BCM）码。通过MSAT信道传输。尽管对于AWGN信道，BCM通常在功率效率上不及TCM，但由于BCM的解码深度更短，因此交织更为有效，因此它在MSAT信道中具有与TCM竞争的巨大潜力。长度最大为32的二进制Reed-Muller（RM）代码用作组件代码。仿真结果表明，这些代码在未编码的参考系统上可获得良好的编码增益，并且在相同的解码复杂度上胜过TCM代码。第三部分，一种简单而系统的技术来构造多级串联BCM方案，以在阴影MSAT信道上进行数据传输并给出了瑞利衰落信道。这些方案旨在实现高性能或大编码增益，同时降低解码复杂度。构造基于多级串联方法，在该方法中，将长而有效的（二进制或非二进制）代码用作外部代码，并将由线性BCM代码及其子代码构造的陪集代码用作内部代码。仿真结果表明，这些代码在未编码的参考系统上具有较大的编码增益，并且在内部代码相同的情况下，性能优于单级串联BCM代码。特别是一些多层级联的BCM码在BER为10时实现了无误码通信；在论文的最后部分，采用多层级联的方法构造了产品编码调制方案。在乘积编码调制中，乘积编码技术和编码调制相结合以实现高性能，同时降低了解码复杂度。优质的8-PSK调制码可用于各种阴影MSAT信道。仿真结果表明，这些代码在未编码的参考系统上具有较大的编码增益，并且在内部代码相同的情况下，性能优于单级串联BCM代码。

著录项

  • 作者

    Rhee, Dojun.;

  • 作者单位

    University of Hawai'i at Manoa.;

  • 授予单位 University of Hawai'i at Manoa.;
  • 学科 Engineering Electronics and Electrical.;Physics Acoustics.;Physics Astronomy and Astrophysics.
  • 学位 Ph.D.
  • 年度 1995
  • 页码 303 p.
  • 总页数 303
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

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