DocumentCode :
1209199
Title :
Effects of nonlinear distortion on switched multibeam FDMA systems
Author :
Wennström, Mattias ; Öberg, Tommy ; Rydberg, Anders
Author_Institution :
Atelier Telecom AB, Kista, Sweden
Volume :
51
Issue :
3
fYear :
2003
fDate :
3/1/2003 12:00:00 AM
Firstpage :
575
Lastpage :
584
Abstract :
The effects of using a multicarrier amplifier (MCPA) in the transmit chain of a cellular frequency-division multiple-access system utilizing switched multibeam base-station antennas is investigated. By combining several carriers prior to amplification, the signal envelope will be time varying and the MCPA will introduce nonlinear distortion of the amplified waveforms. It is shown how the main beam direction and frequency of any intermodulation product of any order can be calculated. A frequency allocation scheme is presented that reduces the intermodulation distortion for the mobile users. By Monte Carlo simulations, the probability distribution function of the received intermodulation distortion power is estimated, assuming a GSM system, as a function of the number of antenna elements and the number of active users. Comparisons with a one-element reference antenna are made, and it is shown that the received intermodulation distortion power for the users in the system is substantially reduced when the number of beams is increased or the user activity is reduced.
Keywords :
Monte Carlo methods; cellular radio; frequency allocation; frequency division multiple access; intermodulation distortion; multibeam antennas; nonlinear distortion; GSM system; Monte Carlo simulations; antenna elements; base-station antennas; cellular frequency-division multiple-access system; frequency allocation scheme; intermodulation product; multicarrier amplifier; nonlinear distortion; one-element reference antenna; probability distribution function; received intermodulation distortion power; signal envelope; switched multibeam FDMA systems; user activity; Antenna arrays; Array signal processing; Downlink; Frequency division multiaccess; Frequency estimation; GSM; Hardware; Intermodulation distortion; Nonlinear distortion; Transmitting antennas;
fLanguage :
English
Journal_Title :
Antennas and Propagation, IEEE Transactions on
Publisher :
ieee
ISSN :
0018-926X
Type :
jour
DOI :
10.1109/TAP.2003.809846
Filename :
1201334
Link To Document :
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