Wideband direct conversion for multi-carrier base stations

This paper proposes a high performance multi-carrier broadband transmitter and receiver for base stations radio cards, addressing the challenges associated with 3G/4G broadband radio designs. The solution is based on a direct conversion approach. The transmitter and receiver use broadband quadrature modulator and demodulator respectively, as well as a wideband synthesizer with integrated VCO for local oscillator generation. This compact and cost effective solution allows transmission and reception of multiple adjacent modulated signals from 400 MHz to 4 GHz with superior signal quality and minimum impairments.