Title :
A multimode adaptive beamformer for quadrature-amplitude-modulated signals
Author :
Gooch, Richard P. ; Sublett, Brian J.
Author_Institution :
Appl. Signal Technol. Inc., Sunnyvale, CA, USA
Abstract :
The authors present the results of recent work on an adaptive beamformer designed to enhance the reception of N-state quadrature amplitude modulated (N-QAM) signal in the presence of multipath distortion and cochannel interference. Adaptation of the beamformer is based on a series of performance criteria derived from known properties of the transmitted signal. Neither calibrated look-direction constraints nor prearranged training signals are required. Instead, the beamformer uses blind adaptation to initially suppress multipath distortion and cochannel interference and then switches into decision-directed adaptation to achieve optimal combining
Keywords :
amplitude modulation; diversity reception; interference suppression; radio links; signal detection; N-QAM; blind adaptation; cochannel interference; decision-directed adaptation; diversity reception; multimode adaptive beamformer; multipath distortion; optimal combining; quadrature-amplitude-modulated signals; radio links; signal reception enhancement; Adaptive equalizers; Algorithm design and analysis; Dispersion; Distortion; Diversity reception; Fading; Interchannel interference; Interference constraints; Phase measurement; Spread spectrum communication;
Conference_Titel :
Acoustics, Speech, and Signal Processing, 1988. ICASSP-88., 1988 International Conference on
Conference_Location :
New York, NY
DOI :
10.1109/ICASSP.1988.197224
