Transceiver signal processor for digital, cordless telephone

摘要

The pressor has a transmitter for conversion and transmission of a signal as a radio wave via an aerial input, and a receiver for connecting the signal from the aerial input for processing. A frequency synthesiser has a first PLL (120) for channel conversion, during which the loop frequency of the PLL is not switched over. A received second IF is used for setting a corresp. offset at 0 Hz. A second PLL (130) provides high oscillation change-over between the transmit and reception frequency by setting the output frequency of the first PLL as a reference signal.