LOW-POWER DIRECT DIGITAL FREQUENCY SYNTHESIZER ARCHITECTURE

摘要

A direct digital frequency synthesizer forgenerating a digital. sine or cosine function waveformincludes input means to receive digital input.Memory stores digital samples along portions of sineand cosine function waveforms. The memory outputsthe digital samples in response to a first portion ofthe digital input. Control logic responsive to theinput means controls the output of the digitalsamples from the memory to allow digital samplesalong a complete cycle of the sine or cosine functionwaveform to be output even though only portions ofthe sine and cosine function waveforms are stored inthe memory. Linear interpolation means receives asecond portion of the digital input and modifiesdigital samples output by the memory to generateintermediate digital samples between the digitalsamples stored in the memory to improve accuracy.