Channel estimation using linearly constrained filter coefficients

A method for reference symbol aided channel estimation comprising the steps of:

• selecting a set of demodulator output samples and a corresponding set of reference symbols each having a magnitude;
• generating a set of raw channel estimates based on the set of demodulator output samples and the corresponding set of reference symbols;
• subdividing the set of raw channel estimates into a plurality of subsets;
• applying a corresponding reference symbol magnitude quantization scheme to each subset;
• scaling each raw channel estimate in the subsets by a corresponding weighting value to generate a set of scaled raw channel estimates, wherein the corresponding weighting value is based on the magnitude of the reference symbol used to generate the corresponding raw channel estimate and the applied quantization scheme;
• determining a set of linearly-constrained filter coefficient parameters;
• and
• combining the set of scaled raw channel estimates with the set of linearly-constrained filter coefficient parameters to generate a channel estimate.

A receiver comprising:

• at least one antenna element for receiving a signal;
• receiver circuitry for generating a baseband signal from the received signal;
• a demodulator for generating output samples from the baseband signal;
• and
• a processor configured for performing the steps of:
• selecting a set of demodulator output samples and a corresponding set of reference symbols each having a magnitude;
• generating a set of raw channel estimates based on the set of demodulator output samples and the corresponding set of reference symbols;
• determining a set of linearly-constrained filter coefficient parameters;
• and
• combining the set of raw channel estimates with the set of linearly-constrained filter coefficient parameters to generate a channel estimate.