VLSI Implementation of Block Error Correction Coding Techniques

Communication Engineering has become the most vital field of Engineering in today’s life. The world is dreaded to think beyond any communication gadgets. Data communication basically involves transfers of data from one place to another or from one point of time to another. Error may be introduced by the channel which makes data unreliable for user. Hence we need different error detection and error correction schemes. In the present work, we perform the comparative study between different FECs like Turbo codes, Reed-Solomon codes and LPDC codes. But among all these we find Reed Solomon to be most efficient for data communication because of low coding complexity and high coding rate. The RS codes are non-binary, linear and cyclic codes used for burst error correction. They are used in numerous applications like CDs, DVDs and deep space communication. We simulate RS Encoder and RS Decoder for double error correcting RS (7, 3) code. Then we implement RS (255,239) code in VHDL. In RS (255,239) code, each data symbol consists of 8 bits which is quite practical as most of the data transfer is done in terms of bytes. The implementation has been done in the most efficient algorithms to optimize the design in terms of space utilization and latency of the code. The behavioral simulation has been carried out for each block and for the whole design also. Finally, the FPGA utilization and clock cycles needed are analyzed and compared with the already developed designs

Performance of encoding/decoding of bit strings using coded sound signals.

Encryption of the data using coded sound signals and evaluation of the performance of the coded sound signal.Encryption of the data using coded sound signals and evaluation of the performance of the coded sound signal

Hardware Implementations of CCSDS Deep Space LDPC Codes for a Satellite Transponder

Error-correction coding is a technique that adds mathematical structure to a message, allowing corruptions to be detected and corrected when the message is received. This is especially important for deep space satellite communications, since the long distances and low signal power levels often cause message corruption. A very strong type of error-correction coding known as LDPC codes was recently standardized for use with space communications. This project implements the encoding and decoding algorithms required for a small satellite radio to be able to use these LDPC codes. Several decoder architectures are implemented and compared by their performance, speed, and complexity. Using these LDPC decoders requires knowledge of the received signal and noise levels, so an appropriate algorithm for estimating these parameters is developed and implemented. The LDPC encoder is implemented using a flexible architecture that allows the entire standardized family of ten LDPC codes to be encoded using the same hardware

An investigation of error correcting techniques for OMV data

Papers on the following topics are presented: considerations of testing the Orbital Maneuvering Vehicle (OMV) system with CLASS; OMV CLASS test results (first go around); equivalent system gain available from R-S encoding versus a desire to lower the power amplifier from 25 watts to 20 watts for OMV; command word acceptance/rejection rates for OMV; a memo concerning energy-to-noise ratio for the Viterbi-BSC Channel and the impact of Manchester coding loss; and an investigation of error correcting techniques for OMV and Advanced X-ray Astrophysics Facility (AXAF)

Low-complexity iterative detection techniques for Slow-Frequency-Hop spread-spectrum communications with Reed-Solomon coding.

Slow-frequency-hop (SFH) spread-spectrum communications provide a high level of robustness in packet-radio networks for both military and commercial applications. The use of a Reed-Solomon (R-S) code has proven to be a good choice for use in a SFH system for countering the critical channel impairments of partial-band fading and partial-band interference. In particular, it is effective when reliability information of dwell intervals and individual code symbols can be obtained and errors-and-erasures decoding (EE) can be employed at the receiver. In this dissertation, we consider high-data-rate SFH communications for which the channel in each frequency slot is frequency selective, manifesting itself as intersymbol interference (ISI) at the receiver. The use of a packet-level iterative equalization and decoding technique is considered in conjunction with a SFH system employing R-S coding. In each packet-level iteration, MLSE equalization followed by bounded distance EE decoding is used in each dwell interval. Several per-dwell interleaver designs are considered for the SFH systems and it is shown that packet-level iterations result in a significant improvement in performance with a modest increase in detection complexity for a variety of ISI channels. The use of differential encoding in conjunction with the SFH system and packet-level iterations is also considered, and it is shown to provide further improvements in performance with only a modest additional increase in detection complexity. SFH systems employing packet-level iterations with and without differential encoding are evaluated for channels with partial-band interference. Comparisons are made between the performance of this system and the performance of SFH systems using some other codes and iterative decoding techniques