Patent ID: 11916704
Assignee: HUGHES NETWORK SYSTEMS, LLC
Field: Digital communication (Electrical engineering)
Classification: CPC H | IPC H

Claim 8:
9. A pre-equalizer system comprising:
an integrated circuit substrate configured for integration into a satellite demodulator;
a dynamic coefficient processor disposed on the integrated circuit substrate to receive a segment of a channel-distorted sample stream, compute an updated set of compensation filter coefficients based on correlating the segment of the channel-distorted sample stream to a predetermined training sequence, and output the updated set of compensation filter coefficients;
a pre-equalizer filter block disposed on the integrated circuit substrate and having:
an input node configured to couple with an analog-to-digital converter (ADC) output of an ADC block to receive a stream of digital samples generated by the ADC block from analog forward downlink communications received via a satellite channel, the forward downlink communications manifesting satellite channel filter distortions associated with one or more channel filters in the satellite channel, such that the stream of digital samples is the channel-distorted sample stream;
a plurality of filter taps configurable based on the updated set of compensation filter coefficients previously computed by the dynamic coefficient processor to at least partially compensate for the satellite channel filter distortions of the satellite channel; and
an output node configured to output, to a demodulator path of the satellite demodulator, an undistorted sample stream by filtering the channel-distorted sample stream according to the plurality of filter taps;

a training buffer disposed on the integrated circuit substrate and coupled with the ADC output to receive the channel-distorted sample stream; and
an update trigger block disposed on the integrated circuit substrate to generate a trigger signal responsive to detecting decoding of a pre-equalizer frame code by the demodulator,
wherein the forward downlink communications include a sequence of communication frames having at least one pre-equalizer frame that each encodes an instance of the pre-equalizer frame code and an instance of the predetermined training sequence of digital symbols, such that the trigger signal indicates receipt of the at least one pre-equalizer frame and corresponding presence in the training buffer of a segment of the channel-distorted sample stream representing at least the predetermined training sequence of digital symbols, and
wherein the dynamic coefficient processor is to receive the segment of the channel-distorted sample stream from the training buffer responsive to the trigger signal.