POSITIVE COEFFICIENT WEIGHTED QUADRATURE MODULATION METHOD AND APPARATUS

摘要

A differential positive coefficient weighted quadrature modulator is actuated responsive to quadrature clock signals and positive digital modulation signals input to the modulator. The modulator includes an l-channel positive coefficient weighted modulator (PCWM) and a Q-channel PCWM. The l-channel PCWM has differential output nodes configured to output a differential l-channel signal responsive to the state of first and second positive digital modulation signals and first and second complimentary quadrature clock signals input to the l-channel PCWM. The Q-channel PCWM has differential output nodes configured to output a differential Q-channel signal responsive to the state of third and fourth positive digital modulation signals and third and fourth complimentary quadrature clock signals input to the Q-channel PCWM. The positive digital modulation signals input to the l-channel and Q-channel PCWMs have positive amplitude and the l-channel and Q-channel PCWMs conduct at approximately half clock cycle or less of the corresponding quadrature clock signals.