Abstract In direct sequence code division multiple access (DS-CDMA), frequency-domain equalization (FDE) based on minimum mean square error (MMSE) criterion can be applied to exploit the channel frequency-selectivity and therefore achieves much improved bit error rate (BER) performance than using the conventional rake combining. Even if FDE is applied to DS-CDMA, however, the uplink BER perform...

In this paper, frequency and time interleaving algorithms used for soft decision Viterbi decoding for OFDM systems, performed on frequency-selective and time-selective channels respectively, are investigated.To achieve optimal performance in terms of Bit Error Rate (BER), the size of the interleavers must be specified depending on the properties of the channel and the characteristics of the cod...

This paper examines the performance by simulation of an intercode interleaving technique, for indoor portable radio channels. The intercode interleaving technique is implemented by placing a bit interleaver between two concatenated BCH codes. The modulation used is d4-shifted DQPSK, with differential detection. The envelope and phase fading in the quasi-static indoor radio channel is modeled by...

We present an analytical method for evaluating the performance of a communication system that employs a convolutional code, a block interleaving with finite interleaving depth, a binary channel that exhibits statistical dependence in the occurrence of errors, and a decoder that implements the Viterbi algorithm with Hamming metric. The main idea is to apply combinatorial methods to derive a form...

A programmable turbo decoder is designed for multiple third-generation (3G) wireless communication standards. It mainly consists of a configurable SISO decoder and a 16-bit SIMD processor equipped with five processing elements and specialized instructions customized for interleaving. A fast and flexible incremental block interleaving algorithm that causes no timing overhead in changing interlea...

In this paper, the theory of fair action systems is used in the speciication and development of the Alternating Bit Protocol. A version of the Movers Theorem for fair action systems is proved, which permits the interleaving of actions of one action system within another. This Movers Theorem is applied repeatedly in the development of the Alternating Bit Protocol.

In this paper, we propose a chaotic interleaving scheme for continuous-phase modulation based orthogonal frequency-division multiplexing (CPM-OFDM) systems. The idea of chaotic maps randomization (CMR) is exploited in this scheme. CMR generates permuted sequences from the sequences to be transmitted with lower correlation among their samples, and hence a better bit error rate (BER) performance ...

The use of frequency-domain interleaving on a frame-byframe basis for orthogonal frequency division multiplexing (OFDM) combined with time division multiplexing (OFDM/TDM) is presented. In conventional OFDM, FDE is not designed to exploit the channel frequencyselectivity and consequently, the frequency diversity gain cannot be obtained. To further improve the bit error rate (BER) performance of...