Method and apparatus for controlling digital filter of a radio transmitter

摘要

A digital filter control method and apparatus is provided. One embodiment of the invention comprises: an analog/digital converter for converting an analog signal to a digital signal; a data processing unit for compressing and error-correcting the digital signal; a coder for coding the signal provided by the data processing unit to an I signal and a Q signal; a digital filter for wave-filtering the I and Q signals; a modulator for modulating the I and Q signals into an intermediate frequency (IF) signal; a mixer for up-converting the IF signal into a radio frequency; a bandpass filter (BPF) for filtering the up-converted radio signal; an amplifier for amplifying the filtered radio frequency signal; and a filter control means for controlling a roll-off factor of the digital filter.