Wideband OFDM Transmitter for Wireless Communications

An OFDM transmitter with digital IF is demonstrated. The OFDM modulator is designed with an on-chip digital to analog converter. An image frequency mixer and an RF amplifier chain is realized partly with commercial GaAs MMIC circuits and partly with discrete transistors. About 10% power added efficiency in the power stage is achieved with ACPR level of -35 dB applying an A-class amplifier.