Title :
Transmitter-based inverse filters for reducing MAI and ISI in CDMA-TDD downlink
Author :
Georgoulis, S.L. ; Cruickshank, D.G.M.
Author_Institution :
Sch. of Eng. & Electron., Univ. of Edinburgh, UK
fDate :
3/1/2004 12:00:00 AM
Abstract :
Inverse filters (INVF) are introduced as a new transmitter-based precoding scheme for the code-division multiple access-time division duplex (TDD) downlink. Multiple access interference and intersymbol interference are significantly reduced while the mobile station´s structure is reduced to a filter matched to the user´s spreading code. The method assumes knowledge of the channel at the transmitter which is feasible under TDD. The new algorithm uses a minimum mean-squared error criterion with power constraint. When compared with existing schemes, INVF increase the system performance while maintaining a low computational cost. The theoretical analysis is supported with simulation results. Analytical bit-error rates for any precoding algorithm is also calculated.
Keywords :
cellular radio; code division multiple access; codes; error statistics; interference suppression; intersymbol interference; least mean squares methods; matched filters; multiuser detection; radio transmitters; radiofrequency interference; time division multiplexing; CDMA-TDD downlink; bit error rates; code division multiple access; intersymbol interference; inverse filters; minimum-squared error criterion; multiple access interference; multiuser detection; power constraints; spreading code; time division duplex; transmitter-based precoding scheme; Analytical models; Computational efficiency; Computational modeling; Downlink; Interference constraints; Intersymbol interference; Matched filters; Multiple access interference; System performance; Transmitters;
Journal_Title :
Wireless Communications, IEEE Transactions on
DOI :
10.1109/TWC.2003.821137