Patent ID: 8149977
Filing Date: 2012-04-03
Classification: H04L

Abstract:
1. Apparatus for recovering synchronous data samples from an asynchronously over-sampled stream of data samples derived from an input signal, where spectral characteristics of the input signal are subject to variation, the apparatus comprising; an FIR filter having an input for receiving the asynchronously over-sampled stream of data samples and operable to produce equalised asynchronous samples; a signal sample reconstruction arrangement operable to reconstruct the synchronous data samples from the equalised asynchronous samples; an automatic gain control loop responsive to a first slicing level error signal to apply gain control for producing gain controlled reconstructed synchronous samples; a slicer arrangement responsive to the gain controlled reconstructed synchronous samples to produce the first slicing level error signal and responsive to reconstructed synchronous samples substantially unaffected by gain control to produce a second slicing level error signal; a timing recovery arrangement responsive to the first error signal to provide timing information to the signal sample reconstruction arrangement; and a coefficient adaptation control loop, responsive to the second error signal to adapt the FIR filter coefficients to the variation in the spectral characteristics of the input signal.