METHOD FOR REDUCING CROSS MODULATION AND TRANSCEIVER EMPLOYING THE METHOD

摘要

PROBLEM TO BE SOLVED: To reduce the cross modulation noise without using a low noise amplifier having the high linearity including a large tertiary breaking point by using a receiving amplifier which receives a receiving signal from a transmission/ reception switch and also has the gain that is modulated by an envelope signal proportional to a transmitting signal. SOLUTION: A transceiver 100 has a base band unit 160 which outputs a base band signal and a modulator 170 which modulates the base band signal and outputs a signal to be modulated. A transmitting amplifier 175 of the transceiver 100 amplifies the signal to be amplified and outputs a transmitting signal to a transmission/reception switch 120. The transceiver 100 also has a receiving amplifier 125 which receives a signal from the switch 120 and has the gain which is modulated by an envelope signal. The envelope signal is proportional to the transmitting signal so as to be proportional to the electric power of the transmitting signal and also to the square root of the electric power and supplied from the unit 160.