To suppress a noise from being mixed into a combined signal in diversity synthesis that uses an AGC and combines a plurality of signals.
A high frequency received by an antenna A1 is converted into an intermediate frequency signal in a multiplier 21. The intermediate frequency signal is amplified by a variable analog amplifier 31 controlled by an AGC 30, an amplified signal is converted into a digital signal by an A/D 41, and the converted signal is demodulated to a digital complex signal of a baseband by a quadrature demodulator 50 and output. The AGC 30 controls a gain of the variable analog amplifier 31 according to an output of the quadrature demodulator 50. The control voltage output of the AGC 30 is also output to a weight calculator 70. The weight calculator 70 calculates each gain from an AGC control voltage to a new weighting factor to which the AGC control voltage is not reflected, calculates the new weighting factor by multiplying an inverse number of the gain, and outputs the new weighting factor to complex multipliers 71, 72, 73 and 74. Consequently, an effect of a branch with a high gain is suppressed for the variable analog amplifiers 31 to 34.
MITA KATSUSHI
HARADA TOMOYASU
ITO NOBURO
| JPH11220346A | 1999-08-10 | |||
| JPH1155169A | 1999-02-26 | |||
| JPH11186946A | 1999-07-09 | |||
| JP2004343586A | 2004-12-02 | |||
| JP2004080191A | 2004-03-11 |
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