Title :
MISO concepts for frequency-selective channels
Author :
Irmer, Ralf ; Fettweis, Gerhard
Author_Institution :
Inst. fdr Nachrichtentechnik, Dresden Univ. of Technol., Germany
Abstract :
In order to limit interference and increase system capacity in CDMA systems, the transmitted power required to achieve a certain performance should be as low as possible. Usually, receivers are designed to overcome the problems caused by the frequency-selective wireless channel. However, if the channel impulse response (CIR) is a priori known at the transmitter, the signal we want to transmit can be preprocessed. The CIR for the downlink can be estimated in the uplink in time-division duplex (TDD) systems or conveyed in a feedback channel from the receiver to the transmitter. By using multiple transmit antennas in multiple-input single-output (MISO) systems, performance improvement potentials are created. Several MISO concepts using FIR filters both in the transmitter and receiver are compared, their decision variables are given and the SNRs at the receivers are calculated analytically. The MISO generalized selection eigenprecoder is derived which offers the possibility to trade off performance and complexity
Keywords :
FIR filters; antenna arrays; cellular radio; code division multiple access; encoding; fading channels; multiuser channels; radiofrequency interference; receiving antennas; spread spectrum communication; transmitting antennas; BER; CDMA systems; FIR filters; MISO; SNR; cellular radio; channel impulse response; complexity; eigenprecoder; feedback channel; frequency-selective channels; frequency-selective fading channels; frequency-selective wireless channel; interference; multiple transmit antennas; multiple-input single-output systems; receivers; spread-spectrum signals; system capacity; time-division duplex systems; transmitter; Downlink; Fading; Finite impulse response filter; Frequency; Interference; Multiaccess communication; Multipath channels; RAKE receivers; Transmitters; Transmitting antennas;
Conference_Titel :
Broadband Communications, 2002. Access, Transmission, Networking. 2002 International Zurich Seminar on
Conference_Location :
Zurich
Print_ISBN :
0-7803-7257-3
DOI :
10.1109/IZSBC.2002.991783