Channel estimator circuitry, and associated method, for a digital communication system

A channel estimator for estimating a channel impulse response of a transmission channel upon which a communication signal having synchronization symbols is transmitted by a transmitter, the communication signal transmitter at a communication signal symbol rate to a receiver, said channel estimator comprising:

• a symbol sampler coupled to receive signals representative of the communication signal received by the receiver, said symbol sampler for sampling values of at least each of the synchronization symbols of the signal at a rate at least corresponding to the communication symbol rate and for generating a sampled signal representative thereof;
• and
• metric calculating circuitry coupled to receive the sampled signal generated by said symbol sampler, said metric calculating circuitry for calculating metrics between portions of the sampled signal and stored data words, the stored data words of values representative of the synchronization symbols modified by selected levels of distortion introduced upon the communications signal by the transmitter and the receiver, prior to transmission and subsequent to reception, respectively, of the communication signal, said metric calculating circuitry further for selecting, responsive to the metrics, a stored data word of the stored data words which corresponds most closely with the sampled signal, thereby to estimate the channel impulse response.

A method for estimating a channel impulse response of a transmission channel upon which a communication signal having synchronization symbols is transmitted by a transmitter, the communication signal transmitted at a communication signal symbol rate to a receiver, said method comprising the steps of:

• sampling values of at least the synchronization symbols of the signal at a sampling rate greater than the communication signal symbol rate, thereby to sample each of the synchronization symbols at least at a first sampling point and at a second sampling point;
• generating at least a first sampled signal and a second sampled signal of values representative of the synchronization symbols sampled at the at least first and second sampling points, respectively, during said step of sampling;
• calculating metrics between portions of the first sampled signal and a stored data word and the second sampled signal, the stored data word of values representative of the synchronization symbols modified by a selected level of distortion introduced upon the communication signal by the transmitter and the receiver, prior to transmission and subsequent to reception, respectively, of the communication signal;
• and
• selecting which of the at least first sampled signal and the second sampled signal corresponds most closely with the stored data word, thereby to estimate the channel impulse response.

A method for estimating a channel impulse response of a transmission channel upon which a communication signal having synchronization symbols is transmitted by a transmitter, the communication signal transmitted at a communication signal symbol rate to a receiver, said method comprising the steps of:

• sampling values of at least each of the synchronization symbols of a signal representative of the communication signal at a rate at least corresponding to the communication signal symbol rate;
• generating a sampled signal representative of the values sampled during said step of sampling;
• calculating metrics between portions of the sampled signal and stored data words, the stored data words of values representative of the synchronization symbols modified by selected levels of distortion introduced upon the communication signal by the transmitter and receiver, prior to transmission and subsequent to reception, respectively, of the communication signal;
• and
• selecting which of the stored data words corresponds most closely with the sampled signal, thereby to estimate the channel impulse response.