PHASE NOISE MEASUREMENT AND FILTERING CIRCUIT

摘要

Methods and apparatuses for measuring a phase noise level in an input signal are disclosed. An input signal can be delayed to generate a delayed version of the input signal. Next, a phase difference can be detected between the input signal and the delayed version of the input signal. A phase noise level in the input signal can then be determined based on the detected phase difference. The measured phase noise level can then be used to suppress phase noise in the input signal.

主权项

1. A phase noise measurement (PNM) circuit, comprising:
a delay circuit, wherein an input of the delay circuit receives a first input signal, and wherein an output of the delay circuit outputs a delayed version of the first input signal; a phase detector (PD), wherein a first input of the PD receives the first input signal, wherein a second input of the PD receives the delayed version of the first input signal, and wherein the PD outputs a first voltage signal that corresponds to a phase difference between the first input signal and the delayed version of the first input signal; and circuitry to generate a second voltage signal based on the first voltage signal, wherein the second voltage signal corresponds to a phase noise level in the first input signal.