Hristo Kostadinov

Derivation on bit error probability of coded QAM using integer codes

Coded modulation refers to the process of combined and jointly optimized channel coding and modulation scheme. In this paper, block coded modulation using integer codes and its performance is evaluated by deriving a formula of its bit error probability for AWGN channel. The probability of correct detection of the received signal is a square of the corresponding probability. The detector correctly demodulates the received signal with an average probability in uncoded and coded case respectively.

Double error correctable integer code and its application to QAM

A new construction of double error correctable integer codes and their application to QAM scheme are presented. Soft decoding algorithm for multiple error correctable integer code which are suited to any modulation scheme (QAM, PSK, ASK) will be introduced. Comparison of bit error rate (BER) versus signal-to-noise ratio (SNR) between soft and hard decoding using integer coded modulation (ICM) shows us that we can obtain approximately 2 dB coding gain.

New Bounds for Probability of Error of Coded and Uncoded TQAM in AWGN Channel

We investigate the performance of coded modulation scheme based on the application of integer codes to triangular quadrature amplitude modulation (TQAM). An upper and a lower bounds for symbol error probability (SER) in the case of AWGN channel are derived. These bounds are so closed that it makes the calculation of the exact value of SER unnecessary in practice.

On coded modulation based on finite rings of integers

In this paper, we investigate the problem how to use codes over /spl Zopf//sub A/ to correct any single error which belongs to the set {/spl plusmn/e/sub 1/,/spl plusmn/e/sub 2/,...,/spl plusmn/e/sub s/}, where e/sub i/s are different elements in /spl Zopf//sub A/. We present some classes of such codes and describe how they can be applied to M-QAM.

Integer Codes for Flash Memories

This paper demonstrates the flexibility of integer codes with regard to various type of applications. New constructions of integer codes correcting asymmetric type of errors are proposed in the paper and how to apply the constructed codes to flash memories is discussed.

Symbol and Bit Error Probability for Coded TQAM in AWGN Channel

Abstract The performance of coded modulation scheme based on the application of integer codes to triangular quadrature amplitude modulation (TQAM) with 22m points constellation is investigated. A method of calculating the exact value of symbol error rate over AWGN channel in the case of TQAM combined with encoding by integer codes is described. Computation of error probability in the coded case is much more difficult because of more complex forms and in a sense uncertainties of decision regions. It is demonstrated that in the coded case computer simulation is a very good alternative. The results of simulations (symbol and bit error probabilities) in the case of coded 16, 64, and 256-TQAM simulations are graphically presented.

Error correcting codes and their usage in steganography and watermarking

Steganography and Digital Watermarking are concerned with embedding information in digital media such as images, audio signals and video. Both scientific disciplines develop methods for conceal message (a sequence of bits) by modifying the host (cover) digital object but their goals are slightly different. In this work we discuss two methods of information embedding in spatial domain: a matrix embedding by q-ary codes and a method based on pseudo-noise patterns and which explodes the erasure capability of error correcting codes. We have made numerous experiments with picture from several galleries (with grey-scale and color images) and many error control codes for both type of algorithms. Our observations show that q-ary codes are good choice in the case of syndrome embedding.