Abstract: A frequency synthesizer for providing clock signals with different frequencies for corresponding band transceivers and associated frequency synthesizing method are provided. The frequency synthesizer includes a phase-locked loop module having a single voltage controlled oscillator, a first frequency divider and a second frequency divider. At first, the single voltage controlled oscillator is activated to generate a primary clock signal. The first frequency divider frequency-divides the primary clock signal to generate a first clock signal for a first band transceiver. The first clock signal is further frequency-divided into a second clock signal for a second band transceiver. Therefore, the frequency synthesizer with the single voltage controlled oscillator can generate clock signals covering more than one frequency band.

Abstract: A clock generator includes a delta sigma modulator, a counter and a first phase lock loop. The delta sigma modulator sequentially generates a plurality of variable parameters according to a predetermined value and a first input clock signal. The counter, which is connected to the delta sigma modulator, is used to generate an output clock signal in accordance with a counting value and a second input clock signal. The counting value is relevant to the variable parameters. The first phase lock loop, which is connected to the output of the counter, is used to generate an objective clock signal in accordance with the output clock signal.

Abstract: A frequency synthesizer for providing clock signals with different frequencies for corresponding band transceivers and associated frequency synthesizing method are provided. The frequency synthesizer includes a phase-locked loop module having a single voltage controlled oscillator, a first frequency divider and a second frequency divider. At first, the single voltage controlled oscillator is activated to generate a primary clock signal. The first frequency divider frequency-divides the primary clock signal to generate a first clock signal for a first band transceiver. The first clock signal is further frequency-divided into a second clock signal for a second band transceiver. Therefore, the frequency synthesizer with the single voltage controlled oscillator can generate clock signals covering more than one frequency band.

Abstract: A clock generator includes a delta sigma modulator, a counter and a first phase lock loop. The delta sigma modulator sequentially generates a plurality of variable parameters according to a predetermined value and a first input clock signal. The counter, which is connected to the delta sigma modulator, is used to generate an output clock signal in accordance with a counting value and a second input clock signal. The counting value is relevant to the variable parameters. The first phase lock loop, which is connected to the output of the counter, is used to generate an objective clock signal in accordance with the output clock signal.