Optimized multi-pam finite impulse response (FIR) filter
AssigneeMarvell Asia Pte Ltd
InventorsOliver Weiss, Martin Broich
Life of this patent
Estimating the term…
Abstract
A receiver circuit is disclosed. The receiver circuit includes a multi-PAM input circuit to receive a multi-PAM input symbol. The input symbol exhibits one of multiple threshold levels during a sampling period. The threshold levels correspond to a set of M-bit two's-complement values within a defined set of threshold values. An adaptive filtering circuit includes a first transcoder to transcode the set of M-bit two's-complement values to a set of N-bit values, where N<M. An adaptive filter operates to filter the set of N-bit values to generate a filtered set of data values. A second transcoder transforms the filtered set of data values to a second set of data values that corresponds to a set of filtered M-bit two's-complement values.
Claims15
A receiver circuit, comprising:
- a multi-PAM input circuit configured to receive a multi-PAM input symbol, the input symbol exhibiting a signal level that falls within one of multiple signal ranges during a sampling period, the signal ranges corresponding to a first set of M-bit two's-complement values, the multi-PAM input circuit configured to identify the input symbol signal level and corresponding M-bit two's-complement code corresponding to the identified signal level;
- and
- an adaptive filtering circuit including
- a first transcoder to transcode the identified M-bit two's-complement code to an N-bit code representing a value from a set of N-bit two's complement values, wherein N<M;
- an adaptive filter to receive the N-bit code and to generate a filtered data value;
- and
- a second transcoder to transform the filtered data value to a second data value that corresponds to a filtered M-bit two's-complement value.
An adaptive filtering circuit including
- a first transcoder to transcode a multi-PAM input symbol encoded in a first M-bit two's-complement value to an N-bit value, wherein N<M;
- an adaptive filter to receive the N-bit value and generate a filtered data value;
- and
- a second transcoder to transform the filtered data value to a second data value that corresponds to a filtered M-bit two's-complement value.
A method of operation for a receiver circuit, the method comprising:
- receiving a multi-PAM input symbol, the input symbol exhibiting a signal level that falls within one of multiple signal ranges during a sampling period, the signal ranges corresponding to a first set of M-bit two's-complement values;
- identifying the input symbol signal level and corresponding M-bit two's-complement code corresponding to the identified signal level;
- and
- adaptively filtering the multi-PAM input symbol, including
- transcoding the identified M-bit two's-complement code, with a first transcoder, to an N-bit code representing a value from a set of N-bit two's complement values, wherein N<M;
- adaptively filtering the N-bit code to generate a filtered data value;
- and
- recoding the filtered data value to a second data value that corresponds to a filtered M-bit two's-complement value.
Dependencies are inferred from the claim text.