Transmitter, RF transmitter signal processor and method for operation of transmitter

摘要

An internal operation of RF IC is adjusted so that the level of an RF transmitter signal is substantially stopped from rising, or made to descend in course of ramp-up of the RF transmitter signal. This adjustment is enabled by ramp-up adjustment data Last 4 symbols contained in preamble data precedent to real transmission data transmitted after completion of ramp-up. The ramp-up adjustment data and real transmission data are supplied from a baseband LSI. The RF transmitter signal contains phase and amplitude modulation components according to the EDGE system. RF IC includes phase and amplitude modulation control loops PM LP and AM LP. Ramp-up of RF power amplifiers PA1 and PA2 is performed by controlling the gain of the first variable amplifier MVGA included in the AM LP according to ramp information. Thus, unwanted radiation's level is reduced during ramp-up of the RF transmitter signal of the RF power amplifiers.