Dual frequency tracking loop for OFDMA systems

摘要

Methods and apparatus for correcting frequency errors between a carrier frequency of a signal received by a wireless device and a reference frequency local to the device. For certain aspects, such a method generally includes receiving a signal in a receiver having an LO producing a reference frequency, a radio frequency (RF) phase-locked loop (PLL), and a digital rotator, estimating a frequency difference between a carrier frequency of the received signal and the LO reference frequency, and applying the estimated frequency difference to the RF PLL and the digital rotator.

主权项

1. A method for wireless communications, comprising:
receiving a signal in a receiver having a resampler, having a local oscillator producing a reference frequency, having a radio frequency phase-locked loop, and having a digital rotator; estimating a frequency difference between a carrier frequency of the received signal and the local oscillator reference frequency; applying a portion of the estimated frequency difference to the radio frequency phase-locked loop; applying a remaining portion of the estimated frequency difference to the digital rotator; and configuring the resampler based on the remaining portion of the estimated frequency difference applied to the digital rotator simultaneously with applying the portion of the estimated frequency difference to the radio frequency phase-locked loop and applying the remaining portion to the digital rotator.