Low Complexity and High Performance Coded Modulation Systems - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Low Complexity and High Performance Coded Modulation Systems write by Sandeep Rajpal. This book was released on 1994. Low Complexity and High Performance Coded Modulation Systems available in PDF, EPUB and Kindle.
Low-complexity Forward Error Correction and Modulation for Optical Communication
Low-complexity Forward Error Correction and Modulation for Optical Communication - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Low-complexity Forward Error Correction and Modulation for Optical Communication write by Masoud Barakatain. This book was released on 2021. Low-complexity Forward Error Correction and Modulation for Optical Communication available in PDF, EPUB and Kindle. A novel low-complexity architecture for forward error correction (FEC) in optical communication is proposed. The architecture consists of an inner soft-decision low-density parity check (LDPC) code concatenated with an outer hard-decision staircase or zipper code. The inner code is tasked with reducing the bit error probability below the level that allows the outer code to deliver on the stringent output bit error rate required in optical communication. A hardware-friendly quasi-cyclic construction is adopted for the inner codes. The concatenated code is optimized by minimizing the estimated data-flow at the decoder. A method is developed to obtain complexity-optimized inner-code ensembles. A key feature emerging from this optimization is that it pays to leave some inner codeword bits completely uncoded, thereby greatly reducing the decoding complexity. The trade-off between performance and complexity of the designed codes is characterized by a Pareto frontier. In binary modulation, up to 71% reduction in complexity is achieved compared to previously existing designs. Higher-order modulation via multilevel coding (MLC) is compared with bit-interleaved coded modulation (BICM) from a performance-versus-complexity standpoint. In both approaches, complexity-optimized error-reducing LDPC inner codes are designed for concatenation with an outer hard-decision code, for various modulation orders. Code designs for MLC are shown to provide significant advantages relative to designs for BICM over the entire performance-complexity tradeoff space, for a range of modulation orders. Codes designed for MLC can operate with 78% less complexity, or provide up to 1.2 dB coding gain compared to designs for BICM. A multi-rate and channel-adaptive inner-code architecture is also proposed. A tool is developed to optimize low-complexity rate- and channel-configurable concatenated FEC schemes via an MLC architecture. Compared to previously existing FEC schemes, up to 63% reduction in decoding complexity, or up to 0.6 dB coding gain is obtained. Code designs for MLC in combination with four-dimensional signal constellations are also considered. The design method is generalized to obtain complexity-optimized non-binary LDPC codes to concatenate with outer zipper codes. Gains of up to 1 dB over the conventional schemes are reported. The possibility of using a novel class of nonlinear codes in FEC design is also investigated.
LDPC Coded Modulations
LDPC Coded Modulations - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook LDPC Coded Modulations write by Michele Franceschini. This book was released on 2009-04-09. LDPC Coded Modulations available in PDF, EPUB and Kindle. This book focuses on the analysis and design of low-density parity-check (LDPC) coded modulations, which are becoming part of several current and future communication systems, such as high-throughput terrestrial and satellite wireless networks. In this book, a two-sided perspective on the design of LDPC coded systems is proposed, encompassing both code/modulation optimization (transmitter side) and detection algorithm design (receiver side). After introducing key concepts on error control coding, in particular LDPC coding, and detection techniques, the book presents several relevant applications. More precisely, by using advanced performance evaluation techniques, such as extrinsic information transfer charts, the optimization of coded modulation schemes are considered for (i) memoryless channels, (ii) dispersive and partial response channels, and (iii) concatenated systems including differential encoding. This book is designed to be used by graduate students working in the field of communication theory, with particular emphasis on LDPC coded communication schemes, and industry experts working on related fields.
Low Complexity Block Coded Modulation
Low Complexity Block Coded Modulation - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Low Complexity Block Coded Modulation write by Richard G. C. Williams. This book was released on 1988. Low Complexity Block Coded Modulation available in PDF, EPUB and Kindle.
Coded Modulation Systems
Coded Modulation Systems - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Coded Modulation Systems write by John B. Anderson. This book was released on 2006-04-11. Coded Modulation Systems available in PDF, EPUB and Kindle. Coded Modulation Systems is an introduction to the subject of coded modulation in digital communication. It is designed for classroom use and for anyone wanting to learn the ideas behind this modern kind of coding. Coded modulation is signal encoding that takes into account the nature of the channel over which it is used. Traditional error correcting codes work with bits and add redundant bits in order to correct transmission errors. In coded modulation, continuous time signals and their phases and amplitudes play the major role. The coding can be seen as a patterning of these quantities. The object is still to correct errors, but more fundamentally, it is to conserve signal energy and bandwidth at a given error performance. The book divides coded modulation into three major parts. Trellis coded modulation (TCM) schemes encode the points of QAM constellations; lattice coding and set-partition techniques play major roles here. Continuous-phase modulation (CPM) codes encode the signal phase, and create constant envelope RF signals. The partial-response signaling (PRS) field includes intersymbol interference problems, signals generated by real convolution, and signals created by lowpass filtering. In addition to these topics, the book covers coding techniques of several kinds for fading channels, spread spectrum and repeat-request systems. The history of the subject is fully traced back to the formative work of Shannon in 1949. Full explanation of the basics and complete homework problems make the book ideal for self-study or classroom use.
