Performance Analysis of Iterative Turbo Decoding Stopping Criteria with Quadrature Amplitude Modulation

Two simple stopping criteria for turbo decoding

This paper presents two simple and effective criteria for stopping the iteration process in turbo decoding with a negligible degradation of the error performance. Both criteria are devised based on the cross-entropy (CE) concept. They are as efficient as the CE criterion, but require much less and simpler computations.

A Low-Complexity Stopping Criterion for Iterative Turbo Decoding

This letter proposes an efficient and simple stopping criterion for turbo decoding, which is derived by observing the behavior of log-likelihood ratio (LLR) values. Based on the behavior, the proposed criterion counts the number of absolute LLR values less than a threshold and the number of hard decision 1’s in order to complete the iterative decoding procedure. Simulation results show that the...

Comparison and Analysis of Stopping Rules for Iterative Decoding of Turbo Codes

Noncoherent iterative (turbo) decoding

Recently, noncoherent sequence detection schemes for coded linear and continuous phase modulations have been proposed, which deliver hard decisions by means of a Viterbi algorithm. The current trend in digital transmission systems toward iterative decoding algorithms motivates an extension of these schemes. In this paper, we propose two noncoherent soft-output decoding algorithms. The first sol...

Quadrature Amplitude Modulation

The simplest type of digital modulation involves transmitting a sequence of waveforms (“symbols”) si(t) of equal durationT where eachwaveform is chosen independently from a set of M. This allows us to transmit up to b = log2(M) bits per symbol. A common sets of such symbols are those where the real and imaginary parts of the complex baseband signal are each modulated in amplitude. This known as...