A Digitally Controlled Oscillator for wireless communication application

In order to solve the defects in performance for analog RF circuit in deep submicron process, this paper discusses a new type of LC oscillators, that is Digitally Controlled Oscillator (DCO), which uses digital RF method to achieve the technology requirements of wireless communication. This new type of oscillator uses MOS varactor arrays to moderating the output frequency , through the using of digitally Sigma-Delta technology , we can get more precise resolution , and through using three modes progressively working way can make this kind of structure easily implement in process.