Multi carrier modulation (MCM) technique is essential for next generation wireless mobile communication system, which achieves high data rate with high spectral efficiency and high flexibility. Orthogonal Frequency Division multiplexing (OFDM) introduces multicarrier concept in Code Division Multiple Access (CDMA) to give rise to novel concept of MC-CDMA system. The OFDM mitigates multiple acce...

Fading in wireless environments is a major obstacle to reliable communications. In order to mitigate the e ects of fading, channel coding is often employed. In this thesis, the performance and design of the channel coding technique, turbo codes, [1] is examined over Rayleigh fading channels. The thesis considers coherent BPSK signaling over both time-correlated and fully-interleaved Rayleigh, s...

Wireless communication at near-capacity transmission throughputs is facilitated by employing sophisticated Error Correction Codes (ECCs), such as turbo codes. However, real time communication at high transmission throughputs is only possible if the challenge of implementing turbo decoders having equally high processing throughputs can be overcome. This motivates the implementation of turbo deco...

Bit interleaved coded modulation employing asymmetric turbo codes is investigated. An asymmetric turbo code uses two different constituent codes. The benefit of using different constituent codes is that they may complement each other during iterative decoding of the asymmetric turbo code. This can be visualized using the input-output extrinsic information transfer (EXIT) chart based on mutual i...

Absfract-It has long been recognized that graphical representations of parallel concatenated codes contain loops. These loops make it extremely difficult to use the standard, probabilistic methods for graphs to obtain any insight as to the functionality of turbo decoding. Graphbased techniques do, however, lead to useful extensions and generalizations of the turbo decoding concept. In this pape...

Turbo codes have gained considerable attention since their introduction by Berrou and al. in 1993 due to their near capacity performance and low decoding complexity. The conventional turbo code is a parallel concatenation of two identical recursive systematic convolutional encoders separated by a pseudo-random interleaver. In this work, we propose a modified three Dimensional Turbo Code (3D-TCs...

Turbo codes achieve performance near the Shannon limit. Standard sequential VLSI implementation of turbo decoding requires many iterations and incurs a long latency, which cannot be tolerated in some applications. A novel parallel VLSI architecture for turbo decoding is described, comprising multiple SISO elements, operating jointly on one turbo coded block, and a new parallel interleaver. Late...

The performance and design of turbo codes using coherent BPSK signaling on the Rayleigh fading channel is considered. In low signal-to-noise regions, performance analysis uses simulations of typical turbo coding systems. For higher signalto-noise regions beyond simulation capabilities, an average upper bound is used in which the average is over all possible interleaving schemes. Fully interleav...

Peter C. Massey and Daniel J. Costello, Jr. Dept. of Ele . Engr. University of Notre Dame Notre Dame, IN 46556 Phone: 219-631-5483, Fax: 219-631-4393 E-mail: pmassey nd.edu ostello.2 nd.edu Abstra t: Several new lasses of asymmetri turbo odes are introdu ed whi h o er improved performan e ompared to the original turbo ode over the entire range of signal-to-noise ratios. The new turbo odes make ...

| We study the performance of turbo codes for magnetic recording channels using realistic channel models. Our main objective is to provide a benchmark for the future studies on the subject. We examine a variety of schemes including the use of parallel concatenated turbo codes with and without turbo equalization and convolutional codes with an interleaver (can be regarded as a serial concatenati...