DocumentCode :
2090962
Title :
Adaptive compensation for microwave linearizer
Author :
Buoli, C. ; Cervi, L.A. ; Abbiati, A.
Author_Institution :
SIEMENS Telecomunicazioni S.p.A., 20060 Cassina de´´Pecchi (MI) - Italy
fYear :
1993
fDate :
6-10 Sept. 1993
Firstpage :
439
Lastpage :
442
Abstract :
This paper presents a new adaptive microwave linearizer compensation system against temperature drifts and operating frequency variations (1). The main principle rests on the fact that for a QAM modulated RF carrier the signal envelope exhibits a fixed peak value to average value ratio which depends only on the constellation and on the roll-off factor. It follows that the peak to average value ratio of the SSPA output signal envelope has to be constant when the SSPA operates in the linear amplitude region. Moreover the peak to average ratio decreases or increases as the amplifier goes through a gain compression or gain expansion due to a change in temperature, operating frequency or in any other parameter. Therefore it can be used as a criterion on which to base the amount of AM/AM compensation to be introduced by the linearizer. This method exhibits good performance in a wide range of temperatures and frequencies while employing easy to implement low cost hardware.
Keywords :
Amplitude modulation; Constellation diagram; Equations; Frequency measurement; Peak to average power ratio; Quadrature amplitude modulation; Radio frequency; Radiofrequency amplifiers; Temperature distribution; Virtual manufacturing;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Microwave Conference, 1993. 23rd European
Conference_Location :
Madrid, Spain
Type :
conf
DOI :
10.1109/EUMA.1993.336589
Filename :
4136650
Link To Document :
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