We consider the problem of mitigating intersymbol interference (ISI) due to multipath fading as well as multiple-access interference (MAI) in direct sequence code-division multiple-access (DS-CDMA) systems. The proposed multiuser receiver is based on the constant-modulus algorithm (CMA), which is known to provide satisfactory performance in a blind setting. In order to overcome the CMA interference capture problem typical of a multiuser scenario, we propose to adopt a two-stage receiver: in the first stage, partial MAI suppression is achieved by exploiting the desired user signature structure properties; in the second stage, based on CMA, the residual MAI and the ISI are removed, and the desired symbols are reliably recovered. Computer simulations show that, in a severe multipath environment, the proposed blind approach achieves a significant performance gain in comparison with existing blind methods.
Two-stage CMA blind multiuser detection for DS-CDMA systems in multipath fading / Gelli, Giacinto; Verde, Francesco. - STAMPA. - (2001), pp. 622-627. (Intervento presentato al convegno 2nd International Symposium on Image and Signal Processing and Analysis (ISPA'2001) tenutosi a Pula (Croatia) nel Giugno 2001) [10.1109/ISPA.2001.938702].
Two-stage CMA blind multiuser detection for DS-CDMA systems in multipath fading
GELLI, GIACINTO;VERDE, FRANCESCO
2001
Abstract
We consider the problem of mitigating intersymbol interference (ISI) due to multipath fading as well as multiple-access interference (MAI) in direct sequence code-division multiple-access (DS-CDMA) systems. The proposed multiuser receiver is based on the constant-modulus algorithm (CMA), which is known to provide satisfactory performance in a blind setting. In order to overcome the CMA interference capture problem typical of a multiuser scenario, we propose to adopt a two-stage receiver: in the first stage, partial MAI suppression is achieved by exploiting the desired user signature structure properties; in the second stage, based on CMA, the residual MAI and the ISI are removed, and the desired symbols are reliably recovered. Computer simulations show that, in a severe multipath environment, the proposed blind approach achieves a significant performance gain in comparison with existing blind methods.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.