Sparse channel estimation for orthogonal frequency division multiplexed signals

A communication device, for use in a communication system implementing orthogonal frequency division multiplexing (OFDM), comprising:

• a receiver subsystem configured to receive an OFDM symbol from a communication channel, wherein the OFDM symbol includes a plurality of data subcarriers, and
• an equalization subsystem including:
• a pilot vector unit configured to extract a pilot vector from the OFDM symbol;
• a subcarrier tracking unit configured to track subcarriers of interest, wherein subcarriers of interest are those data subcarriers assigned to user terminals on a dynamic basis;
• an interpolation vector retrieval unit configured to retrieve an interpolation vector stored in a memory for each subcarrier of interest;
• and
• a computation unit configured to generate an equalization coefficient for each subcarrier of interest by calculating a dot product between the pilot vector and each retrieved interpolation vector and to modify the subcarriers of interest within the received OFDM symbol using the equalization coefficients.

A radio frequency (RF) transceiver comprising:

• a receiver subsystem configured to receive an orthogonal frequency division multiplexing (OFDM) symbol from a communication channel, wherein the OFDM symbol includes a plurality of data subcarriers;
• and
• an equalization subsystem including:
• a pilot vector unit configured to extract a pilot vector from the OFDM symbol;
• a subcarrier tracking unit configured to track subcarriers of interest, wherein a subset of the plurality of data subcarriers are dynamically assigned to a user terminal, and wherein the subcarriers of interest are those data subcarriers assigned to user terminals;
• a flash memory to store a predetermined interpolation vector for each subcarrier of interest;
• an interpolation vector retrieval unit configured to retrieve a interpolation vector for each subcarrier of interest from the flash memory;
• and
• a computation unit configured to generate an equalization coefficient for each subcarrier of interest by calculating a dot product between the pilot vector and each of the retrieved interpolation vectors and modify the subcarriers of interest within the received OFDM symbol using the equalization coefficients.