The Minimum Mean Square Error (MMSE) receiver is a widely known linear de-tector that reduces the Multiple Access Interference (MAI) in DS-CDMA systems. Its optimal implementation in frequency selective scenarios requires the knowledge of the received signal covariance matrix and of the channel signature waveform that impairs the communication of each user. These quantities are generally not known and therefore they must be estimated by some techniques. This paper considers a chip-based MMSE receiver with a blind channel estimation technique characterised by a subspace approach. The aim is to investigate by simulations the BER degradation caused by the estimation errors of the covariance matrix and of the channel signature waveform, in order to point out problems and limitations in a realistic environment.
Estimation Errors Sensitivity of MMSE Multiuser Receivers in DS-CDMA
BANELLI, Paolo;CACOPARDI, Saverio;RUGINI, LUCA
2001
Abstract
The Minimum Mean Square Error (MMSE) receiver is a widely known linear de-tector that reduces the Multiple Access Interference (MAI) in DS-CDMA systems. Its optimal implementation in frequency selective scenarios requires the knowledge of the received signal covariance matrix and of the channel signature waveform that impairs the communication of each user. These quantities are generally not known and therefore they must be estimated by some techniques. This paper considers a chip-based MMSE receiver with a blind channel estimation technique characterised by a subspace approach. The aim is to investigate by simulations the BER degradation caused by the estimation errors of the covariance matrix and of the channel signature waveform, in order to point out problems and limitations in a realistic environment.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
