Digitally controlled oscillator with storage based randomization for spurs reduction
This paper presents a storage based randomization method for spurs reduction in digitally controlled oscillator (DCO). The storage size is very compact as compared with conventional large size. A modified linear feedback shift register is applied for random address generator. The proposed method has been demonstrated in field programmable gate array (FPGA) with a digitally controlled oscillator. The spurious-free dynamic range (SFDR) of proposed method is 32.3 dB as compared with conventional method's 28.9 dB. The proposed method has successfully reduced the spurs with very small storage for randomization.