Patent ID: 7376399

Claim:
Transmit path circuitry for a communication system, comprising: transmit circuitry coupled to receive a signal at an intermediate frequency (IF) and to output a transmit signal at a desired output frequency; oscillator circuitry configured to output a local oscillator (LO) signal; mixing signal generation circuitry configured to receive the LO signal and to output I and Q mixing signals that differ by an amount other than 90-degrees; and mixing circuitry coupled to receive the I and Q mixing signals from the mixing signal generation circuitry and to output the IF signal to the transmit circuitry, the mixing circuitry being configured to perform a weighted mix of I and Q baseband signals and the I and Q mixing signals to produce the IF signal; wherein an I mixing signal is mixed with a weighted version of the I baseband signal and with a weighted version of the Q baseband signal, and wherein a Q mixing signal is mixed with a weighted version of the I baseband signal and with a weighted version of the Q baseband signal; and wherein a first weighting is used for the Q baseband signal with respect to the I mixing signal and for the I baseband signal with respect to the Q mixing signal, and a second weighting is used for the Q baseband signal with respect to the Q mixing signal and for the I baseband signal with respect to the I mixing signal.