This paper presents a bi-level quadraturemodulation (QM) low-pass (LP) envelope-pulse-widthmodulation (EPWM) transmitter using a half side of tri-level EPWM. Simulation including digital signal processing with the QM LP-EPWM and microwave circuit simulation with a class-D power amplifier (PA) using n-MOSFETs shows an excellent error vector magnitude (EVM) of 36 dB at 1 GHz. The transmitter with a class-D PA for bi-level EPWM signal shows much better EVM performance than the one for trilevel signal.Index Terms -transmitterpower amplifierclass-D envelope pulse-width modulationquadrature modulation, error vector magnitudepower-added efficiency

We previously proposed a bilevel quadrature-modulation (QM) envelope-pulse-width-modulation (EPWM) transmitter using half a side of a trilevel EPWM architecture. However, the optimum relationship between the  modulation (DSM) sampling frequency (f s ), the interleaving frequency (f i ) and the carrier frequency (f c ) for a bilevel QM EPWM transmitter has not been investigated. This paper presents this optimum relationship, with the error vector magnitude (EVM) and the coding efficiency (CE) as figures of merit (FOMs).