A reference frequency generation method and apparatus for communication systems that transmit and receive data by use of an ultra wide band of at least two frequency groups having at least two reference frequencies. The method and apparatus generate the reference frequencies by generating generation frequencies by use of a frequency generated from the local oscillator, and generating adjustment frequencies for adjusting the generation frequency. One generation frequency and one adjustment frequency are selected from the generation frequencies and adjustment frequencies, and the reference frequencies are generated by use of the selected generation frequency and adjustment frequency.