An Adaptive Blind Receiver for Asynchronous Ds-cdma Based on Recursive Svd and Rls
نویسندگان
چکیده
| In this paper we present an adaptive blind receiver for asynchronous direct sequence code division multiple access (DS-CDMA) communication over multipath channels. The algorithm can handle both multiuser interference (MUI) and intersymbol interference (ISI) by the use of a twofold spreading together with some spatial over-sampling. It is based on a blind virtual channel identiication using the singular value decomposition (SVD). Adaptivity is provided by a recur-sive SVD and user-speciic recursive least squares (RLS) schemes for subsequent symbol estimation.
منابع مشابه
Space-Time Joint Interference Cancellation Using Fuzzy-Inference-Based Adaptive Filtering Techniques in Frequency-Selective Multipath Channels
An adaptive minimummean-square error (MMSE) array receiver based on the fuzzy-logic recursive least-squares (RLS) algorithm is developed for asynchronous DS-CDMA interference suppression in the presence of frequency-selective multipath fading. This receiver employs a fuzzy-logic control mechanism to perform the nonlinear mapping of the squared error and squared error variation, denoted by (e2,Δ...
متن کاملMinimum Joint Probability of Error Based Adaptive Multiuser Detection for Multipath DS-CDMA Channels
Absbact-DS-CDMA h a popular multiple access le"logv for wireless rommuniatioar Howwer, its performance is limited by multiple access interference and multipath distortion. Multiuser detection and space lime pmssing are Iwo signal processing techniques employed to improve the performance of DS-CDMA. We propase a blind adaptive spacetime multiuser detedion algorithm in lhis paper. based on the cr...
متن کاملA Low-Complexity Joint Synchronization and Detection Algorithm for Single-Band DS-CDMA UWB Communications
The problem of asynchronous direct-sequence code-division multiple-access (DS-CDMA) detection over the ultra-wideband (UWB) multipath channel is considered. A joint synchronization, channel-estimation, and multiuser detection scheme based on the adaptive linear minimum mean square error (LMMSE) receiver is presented and evaluated. Further, a novel nonrecursive least-squares algorithm capable of...
متن کاملConstrained Adaptive Constant Modulus RLS Algorithm for Blind DS-CDMA Multiuser Receiver under Time-Varying Channels
The performance of the blind multiuser detector for a DSCDMA system with linearly constrained constant modulus (LCCM) criterion is known to highly depend on the exact knowledge of the desired user amplitude; it is usually not available at receiver end. In this paper, we propose a novel LC adaptive CM RLS (LC-ACM-RLS) algorithm to adaptively implement the optimal solution of the LCCM receiver, a...
متن کاملNonlinear Multiuser Receiver for Optimized Chaos-Based DS-CDMA Systems
Chaos based communications have drawn increasing attention over the past years. Chaotic signals are derived from non-linear dynamic systems. They are aperiodic, broadband and deterministic signals that appear random in the time domain. Because of these properties, chaotic signals have been proposed to generate spreading sequences for wide-band secure communication recently. Like conventional DS...
متن کامل