In this paper, we examine the performance enhancements that can be achieved by employing adaptive antennas in Code Division Multiple Access (CDMA) cellular radio systems. The goal is to determine what improvements are possible using narrowbeam antenna techniques, assuming that adaptive algo. rithms and the associated hardware to implement these systems can be realized. Simulations and analytica...

In this paper, we propose an adaptive encoding method of xed codebook in CELP coders and implement an adaptive xed code excited linear prediction (AF-CELP) speech coder. AF-CELP exploits the fact that the xed codebook contribution to speech signal is also periodic as the adaptive codebook (or pitch lter) contribution. By modeling the xed codebook with the pitch lag and the gain from the adaptiv...

The problem of constructing adaptive minimum bit error rate (MBER) linear multiuser detectors is considered for direct-sequence code division multiple access (DS-CDMA) signals transmitted through multipath channels. Based on the approach of kernel density estimation for approximating the bit error rate (BER) from training data, a least mean squares (LMS) style stochastic gradient adaptive algor...

The adaptive antenna array and adaptive modulation aided network performance of a Frequency Division Duplex (FDD) Code Division Multiple Access (CDMA) based system is investigated using system parameters similar to those of the Universal Mobile Telecommunication System (UMTS). A number of performance metrics, such as the call dropping probability, the average throughput as well as the required ...

| Linear minimum mean squared error (LMMSE) criterion can be used to obtain near-far resistant single-user receivers in direct-sequence code-division multiple-access (DS-CDMA) systems. A mod-iied version of the receiver, called LMMSE-RAKE receiver , has previously shown promising performance in frequency-selective fading channels. In this paper, both the convergence and BER performance of an ad...

The Iris recognition has become as one of the promising biometrics feature in human identification system. In addition to conventional IRIS capture challenges, IRIS code searching and similarity matching of IRIS code has also become a challenging task in IRIS code VLOB (Very Large Object database). Hamming Distance (HD), a sequential similarity matching technique, proves in-efficient for VLOB I...

A quantitative theory on the construction and the evolution of the genetic code is proposed. Through introducing the concept of mutational deterioration (MD) and developing a theoretical formalism on MD minimization we have proved: 1,the redundancy distribution of codons in the genetic code obeys MD minimization principle; 2, the hydrophilic-hydrophobic distribution of amino acids on the code t...