Research on UWL signal channelization for Xinjiang 110 m radio telescope

Abstract Aiming at the subband division of UWL (Ultra-Wide wideband Low-frequency) signal (frequency coverage range :704-4032 MHz) of Xinjiang 110 m radio telescope (QTT), a scheme of ultra-wide bandwidth signal is designed. Firstly, we analyze the effect of different window functions such as Hanning window, Hamming window and Kaiser window on the performance of FIR (Finite Impulse Response) digital filters, and implement a CS-PFB (Critical Sampling Polyphase Filter Bank) based on the Hamming window FIR digital filter. Secondly, we generate 3328 MHz simulation data of ultra-wideband pulsar baseband in the frequency range of 704-4032 MHz using the UBPB (Ultra-wide Bandwitdh Pulsar Baseband data generation) algorithm based on the 400 MHz bandwidth pulsar baseband data obtained from Parkes CASPSR observations. Thirdly, we obtain 26 subbands of 128 MHz based on CS-PFB and the simulation data, and the pulse profile of each subband by coherent dispersion, integration, and folding. Finally, the phase of each subband pulse profile is aligned by non-coherent dedispersion, and to generate a broadband pulse profile, which is basically the same as the pulse profile obtained from the original data using DSPSR. The experimental results show that the scheme of QTT UWL reception system is feasible, and the proposed channel algorithm in this paper is effective.