A theoretical analysis of frequency/time quantization noise in polar transmitters

Abstract

The polar transmitter is an increasingly interesting architecture for building up transmitters. One of the most important components of the polar transmitter is the Digitally Controlled Oscillator (DCO). This component takes digital codewords representing instantaneous frequencies as input and produces either square waves or cosine waves with periods corresponding to the instantaneous frequencies. Therefore, it suffers from frequency quantization noise. There are a lot of works in literature which analyze the effect of amplitude quantization. However, no works have been done on analyzing the effect of frequency quantization. In this paper, we perform an analytical study of the frequency quantization in polar transmitters. The analysis helps hardware designers to understand the frequency quantization noise behavior as well as to evaluate the hardware by comparing measurements to theory.