Patent ID: 7856216
Filing Date: 2010-12-21
Classification: H04B

Abstract:
1. A diversity receiver including a plurality of branches each comprised of a direct conversion type receiver, said diversity receiver comprising: a plurality of variable gain amplifiers, the gains of which can be controlled, for amplifying a received signal of each of said branches; a plurality of reception level measuring circuits for measuring a reception level in each of said branches to deliver the result of the measurement; a reception level selector circuit for comparing the results of the measurements of the reception levels in the respective branches to select and deliver the result of the measurement of a maximum reception level which is the highest reception level; and a gain setting circuit for adjusting the variable gain amplifiers of all branches, including variable gain amplifiers belonging to a branch corresponding to the maximum reception level, to the same gain such that output levels of said variable gain amplifiers are set to a preset predetermined value, wherein: said reception level measuring circuit calculates average power of the reception levels on a slot-by-slot basis for each of said branches, said slot indicating a preset predetermined time interval, to deliver the calculated average power as the result of the measurement of the reception level, and said reception level selector circuit determines the maximum reception level for each of the slots by comparing the result of the measurement of the reception for all said branches during each of said slots, and sets all the variable gain amplifiers to the same gain based on the maximum reception level.