Joint estimation of communication channel effects in communication receivers

An apparatus for estimating channel effects on a radio signal conveyed over a communication channel, the apparatus comprising:

• memory circuitry configured to store receiver signal samples;
• and
• processor circuitry configured to:
• generate the receiver signal samples by sequentially sampling a receiver signal at a sampling rate equivalent to a chip rate at which chips of a known signal are timed;
• segment the receiver signal samples into receiver signal segments;
• filter the receiver signal segments by respective matched filters to produce respective filter response sequences, the matched filters being maximally responsive to respective known signal segments segmented from the known signal;
• assign indexes to elements of the filter response sequences to define an array thereof, the elements of the filter response sequences being indexed in a first row order defined by a first sequence order of the known signal segments as distributed across the matched filters and in a first column order defined by a second sequence order in which the receiver signal samples of the receiver signal segments are filtered;
• compute frequency transforms of elements of the filter response sequences indexed in respective columns of the array to produce respective frequency response sequences;
• assign indexes to elements of the frequency response sequences to define another array thereof, the elements of the frequency response sequences being indexed in a second column order defined by a third sequence order in which the receiver signal samples of the receiver signal segments are filtered and in a second row order defined by a fourth sequence order of the frequency response sequences;
• and
• jointly estimate the channel effects from characteristics of the other array at which at least one local maximum is located.

An apparatus for recovering message bits representing information in an information bearing signal conveyed over a communication channel that imparts effects on the information bearing signal, the message bits being timed at a predetermined message bit rate, the apparatus comprising:

• memory circuitry configured for storing receiver signal samples;
• and
• processing circuitry configured to:
• generate the receiver signal samples by sequentially sampling a receiver signal at a sampling rate equivalent to a chip rate at which chips of a known signal are timed;
• segment the receiver signal samples into receiver signal segments;
• filter the receiver signal segments by respective matched filters to produce respective filter response sequences, the matched filters being maximally responsive to respective known signal segments segmented from the known signal;
• assign indexes to elements of the filter response sequences to define an array thereof, the elements of the filter response sequences being indexed in a first row order defined by a first sequence order of the known signal segments as distributed across the matched filters and in a first column order defined by a second sequence order in which the receiver signal samples of the receiver signal segments are filtered;
• compute frequency transforms of elements of the filter response sequences indexed in respective columns of the array to produce respective frequency response sequences;
• assign indexes to elements of the frequency response sequences to define another array thereof, the elements of the frequency response sequences being indexed in a second column order defined by a third sequence order in which the receiver signal samples of the receiver signal segments are filtered and in a second row order defined by a fourth sequence order of the frequency response sequences;
• jointly estimate the channel effects from characteristics of the other array at which local maxima are located;
• and
• generate the message bits from the receiver signal samples using the estimated effects of the communication channel.