Patent ID: 7251291

Claim:
A method of transmitting comprising: generating I/Q imbalance compensation pilot symbols located in time and frequency; generating a set of pilot symbols for channel estimation located in time and frequency; transmitting an orthogonal frequency division multiplexing (OFDM) signal containing the I/Q imbalance compensation pilot symbols and the pilot symbols for channel estimation; wherein the I/Q imbalance compensation pilot symbols are for use by a receiver to perform I/Q imbalance compensation to produce a corrected signal; and the pilot symbols for channel estimation are for use by the receiver to perform channel estimation based on the corrected signal; wherein the step of generating I/Q imbalance compensation pilot symbols comprises the steps of: generating a first transmit signal, including a first plurality of data symbols and a first I/Q imbalance compensation pilot symbol, at a first transmit time, wherein the first l/Q imbalance compensation pilot symbol is represented by a first pilot carrier, having a first predetermined value, and a second pilot carrier, having a different, second predetermined value, located at a first predetermined sample frequency and a second predetermined sample frequency respectively, in a bandwidth of a communication channel; and generating a second transmit signal, including a second plurality of data symbols and a second I/Q imbalance compensation pilot symbol, at a different, second transmit time, wherein the second I/Q imbalance compensation pilot symbol is represented by the first pilot carrier, having a third predetermined value, and the second pilot carrier, having a fourth predetermined value, located at the first predetermined sample frequency and the second predetermined sample frequency, respectively, in the bandwidth of the communication channel; wherein the first pilot carrier and the second pilot carrier are selected so that I/Q imbalance compensation is decoupled from channel estimation by said receiver receiving the first and second transmit signals; wherein the first predetermined sample frequency and the second predetermined sample frequency correspond to a predetermined positive frequency and a predetermined negative frequency, respectively; and the predetermined positive frequency and the predetermined negative frequency are symmetrical about a direct current (DC) frequency in the bandwidth of the communication channel.