A Novel Interpolation Method for Polar Signals in Radio Frequency Transmitters

This contribution describes an arbitrary sampling rate converter architecture for the generation of the modulation signals in polar radio frequency transmitters. The design utilizes a novel look-up table-based interpolation method, which is adaptively employed when certain signal trajectory conditions apply and which allows to deal with the bandwidth expansion inherent to polar signals. Simulation results are presented, which compare the performance of the described architecture to conventional interpolator designs.