Title | Adaptive discrete stochastic approximation algorithms for spreading code optimization in DS/CDMA |
Publication Type | Conference Paper |
Year of Publication | 2003 |
Authors | Krishnamurthy, V., X. Wang, and G. Yin |
Conference Name | Decision and Control, 2003. Proceedings. 42nd IEEE Conference on |
Pagination | 86 - 91 Vol.1 |
Date Published | dec. |
Keywords | adaptive codes, adaptive discrete stochastic approximation algorithms, adaptive step size algorithm, channel coding, code division multiple access, discrete time systems, DS-CDMA, least mean squares methods, linear minimum mean squared error receivers, linear MMSE receivers, mean square convergence, observations, optimisation, radio receivers, radio tracking, self learning capability, spread spectrum communication, spreading code optimization, step size adjustment, stochastic processes, stochastic systems, time varying channel, time-varying channels, tracking analysis, unsupervised learning |
Abstract | The aim of this paper is to present discrete stochastic approximation algorithms that adaptively optimize the spreading codes of users in a CDMA system employing linear MMSE receivers. The proposed algorithm is able to adapt to slowly time-varying channel conditions. One of the most important properties of the algorithm is its self-learning capability - it spends most of the computational effort at the global optimizer of the objective function. A tracking analysis of the adaptive algorithms is presented together with mean square convergence. An adaptive-step-size algorithm is also presented for optimally adjusting the step size based on the observations. |
URL | http://dx.doi.org/10.1109/CDC.2003.1272540 |
DOI | 10.1109/CDC.2003.1272540 |