Method and apparatus for coherent communication in a spread-spectrum communication system

A communication unit comprising:

• (a) demodulating means for despreading a received communication signal with a spreading code to derive a stream of reference samples and a stream of data samples;
• (b) channel estimation means, operatively coupled to the extracting means, for estimating the channel response by utilizing the stream of reference samples;
• and
• (c) detection means, operatively coupled to the extracting means and the channel estimation means, for generating an estimated data symbol from the stream of data samples by utilizing the estimated channel response.

A communication system comprising:

• (a) a transmitter, comprising:
• (i) reference means for inserting reference symbols into a stream of input data symbols to form a reference coded stream of input data symbols;
• (ii) spreading means, operatively coupled to the reference means, for preparing the reference coded stream of input data symbols for transmission over a communication channel by spreading the reference coded stream of input data symbols with a spreading code prior to transmission over the communication channel;
• and
• (iii) a transmitting means, operatively coupled to the spreading means, for transmitting the spread reference coded stream of input data symbols over the communication channel;
• and
• (b) a receiver, comprising:
• (i) receiving means for receiving the communication signal over the communication channel;
• (ii) demodulating means, operatively coupled to the receiving means, for despreading the received communication signal with a spreading code to derive a stream of reference samples and a stream of data samples;
• (iii) channel estimation means, operatively coupled to the extracting means, for estimating the channel response by utilizing the stream of reference samples;
• and
• (iv) detection means, operatively coupled to the extracting means and the channel estimation means, for generating an estimated data symbol from the stream of data samples by utilizing the estimated channel response.

A method of communication comprising:

• (a) despreading a received communication signal with a spreading code to derive a stream of reference samples and a stream of data samples;
• (b) estimating the channel response by utilizing the stream of reference samples;
• and
• (c) generating an estimated data symbol from the stream of data samples by utilizing the estimated channel response.