Generation of Coherent Signals for the Verification of Signal Processing Algorithms in Radio Astronomy

Next generation radio telescopes (e.g. SKA, ngVLA) are required to meet stringent requirements in signal quality. Simulation methods have been extensively used for both design and verification of the signal chains of these telescopes. A key aspect of the simulation methods is the generation of coherent ‘noise-like’ test sequences that mimic celestial radiation and the variation of propagation delays to the different receptors due to the rotation of the Earth. The large decimation factors associated with the signal chains of these radio telescopes require the generation of long sequences of coherent wideband signals. An efficient method based on the chirp-z transform (CZT) for generating wideband coherent pseudo-random test sequences is presented in the following.