Phase noise tracking and reduction

摘要

A group of data symbols for a current block of data symbols in multiple blocks received over a communication channel is equalized, based on a pilot block, to generate a group of equalized symbols. The group of equalized symbols is de-rotated as a function of a current phase estimate to determine initial de-rotated equalized symbols. The phase estimate is an estimate of phase caused by noise for blocks previous to the current block. Additionally, a phase metric is calculated from real and imaginary parts of the initial de-rotated equalized symbols, wherein the phase metric estimates phase caused by noise for the current block. The current phase estimate is updated with the phase metric. The initial de-rotated equalized symbols are de-rotated by the phase metric to determine final equalized and de-rotated symbol estimates. The final equalized and de-rotated symbol estimates are output. Apparatus, methods, and computer program products are disclosed.

主权项

1. A method, comprising:
equalizing by an apparatus, based on a pilot block, a group of data symbols for a current block of data symbols in a plurality of blocks received over a communication channel to generate a group of equalized symbols; de-rotating by the apparatus the group of equalized symbols as a function of a phase estimate to determine initial de-rotated equalized symbols, wherein the phase estimate is an estimate of phase caused by noise for blocks previous to the current block of data symbols; and calculating by the apparatus a phase metric from real and imaginary parts of the initial de-rotated equalized symbols in the group, wherein the phase metric estimates phase caused by noise for the current block; wherein the data symbols form a constellation comprising a plurality of constellation points and comprising inner and outer constellation points, and the phase metric is calculated as a function of the sum of the magnitude of the imaginary part of constellation points in one or more sets of outer constellation points minus the sum of the magnitude of the real part of constellation points in one or more sets of outer constellation points.