Synchronization and acquisition in radio communication systems

摘要

Systems and methods are described for synchronizing a receiver to a received signal and other signal processing approaches and/or components associated with the receiver. For example, a signal (e.g., a radio frequency (RF) signal such as a broadband TV signal in UHF and VHF frequencies) can be received at a receiver. Before the signal is provided to other components of the receiver, the signal can be processed in a component of the receiver commonly known as the digital front-end, where such processing can include amongst others, various synchronization and acquisition techniques.

主权项

1. A method, comprising:
receiving an orthogonal frequency-division multiplexing (OFDM) transmission; analyzing a first portion of the OFDM transmission, the first portion including at least a fixed pilot symbol that carries signaling fields including one or more transmission parameters; determining a coarse carrier frequency offset (CFO) fractional compensation of the OFDM transmission based at least in part on the first portion of the OFDM transmission; determining a guard interval of the OFDM transmission; determining, based at least in part on the guard interval, a fine CFO fractional compensation of the OFDM transmission; performing a Fast Fourier transform (FFT) of the OFDM transmission based at least in part on the CFO fractional compensation and the fine CFO fractional compensation; and tracking at least one of a sampling clock offset (SCO) or a CFO based at least in part on the FFT of the OFDM transmission, wherein at least one of the SCO or the CFO is configured to synchronize at least a portion of a receiver, wherein tracking the CFO further includes:
determining a conjugate product of a first FFT output and a second FFT output of the OFDM transmission, the first FFT output and the second FFT output including one of a plurality of OFDM symbols of the OFDM transmission;determining a phase of the product of the first FFT output and the second FFT output anddetermining an average of the phase of subsequent products of the plurality of OFDM symbols with the phase of the product of the first FFT output and the second FFT output.