DIGITAL IF WIRELESS TRANSMITTER, RF MODULATOR AND MODULATING METHOD, CAPABLE OF ELIMINATING AN UNNECESSARY SIDEBAND BY APPLYING A HIGH FREQUENCY MODULATION MODE

摘要

PURPOSE: A digital IF wireless transmitter, a RF modulator and a modulating method are provided to enhance the effectiveness and linearity of an intermediate frequency modulation using a high frequency modulation mode for a digital intermediate frequency radio transmitter.;CONSTITUTION: An intermediate frequency up converter(110) up-converts an I signal and a Q signal of the base band. A first operation unit(120) subtracts the I signal and the Q signal. A DA converter(130) changes the output of the first operation unit. The intermediate frequency modulator respectively modulates the first and second signals separated from the output of the DA converter. A high pass filter part passes the single-side band of the first signal. The mismatch calibration part compensates the error of the second signal. The second operation unit subtracts the output of the high pass filter part and the output of the mismatch calibration part. A feedback unit extracts the error from the output of the second operation unit. The RF up converter up-converts the output of the second operation unit.;COPYRIGHT KIPO 2010