Use of alias harmonic components in D/A conversion for generating high frequency IF signals

This paper studies on the use of alias harmonic components in D/A conversion for generating high-IF (intermediate frequency) signals. The performance of D/A converter in transmitter is important for high-speed communication, but it restricts the maximum sampling frequency and requires high-cost analog circuits for up conversion. Recalling that the zeroth order hold analog signal generated by D/A converter contains periodic alias harmonic components, high-IF signals can be directly generated from the alias components provided that we have an accurate analog bandpass filter. The results of our simulation and experiments will show that the IF signal of 410MHz and 510MHz can be respectively generated by the 40MHz and 80MHz D/A converters (with zero interpolation in the case of 80MHz), under the condition of EVM (error vector magnitude) less than 6%.