Title :
Hybrid RAKE/multiuser receivers for UWB
Author :
Li, Qinghua ; Rusch, Leslie A.
Author_Institution :
Intel Labs., Intel Corp., Santa Clara, CA, USA
Abstract :
We demonstrate the effectiveness of combining multiple arm RAKE reception with adaptive minimum mean square error (MMSE) combining to combat both narrow and wide band interference in an ultra-wide-band (UWB) pulse-based spread spectrum (SS) communications system. Whether a single user SS UWB system, or a direct sequence SS code division multiple access (CDMA) UWB system, the proposed receiver offers robust suppression of a narrowband interference, in marked contrast to the RAKE only receiver. When DSSS is used with CDMA, this receiver provides much greater rejection of multiuser access interference (wideband interference), avoiding an error floor for moderate system load. RAKE reception alone exhibits an error moderate system load. RAKE reception alone exhibits an error floor even at light system load. The proposed hybrid can be considered an enhancement of RAKE reception, replacing the maximum ration combining the MMSE, or as a reduced complexity alternative to adaptive MMSE multiuser detection.
Keywords :
broadband networks; code division multiple access; diversity reception; interference suppression; least mean squares methods; multiuser detection; radio receivers; radiofrequency interference; spread spectrum communication; ultra wideband communication; CDMA systems; MMSE; UWB system; adaptive minimum mean square error; direct sequence code division multiple access; hybrid RAKE; multiple arm RAKE reception; multiuser detection; multiuser receivers; narrowband interference; pulse-based spread spectrum communications system; robust suppression; ultrawideband systems; wideband interference; Interference suppression; Mean square error methods; Multiaccess communication; Multiuser detection; Narrowband; RAKE receivers; Robustness; Spread spectrum communication; Ultra wideband communication; Ultra wideband technology;
Conference_Titel :
Radio and Wireless Conference, 2003. RAWCON '03. Proceedings
Print_ISBN :
0-7803-7829-6
DOI :
10.1109/RAWCON.2003.1227928