Advances in the QTT Digital Backend: Design, Implementation and Verification

The Xinjiang Qitai Radio Telescope (QTT) in China is equipped with a variety of receivers covering 270 MHz–116 GHz (initially 50 GHz), presenting unique signal acquisition challenges due to varying bandwidths, beams, and locations, along with extreme data rates. To address these challenges, we developed the Wanxiang digital backend employing Radio Frequency System-on-Chip (RFSoC) technology for RF-direct signal digitization and an elastic high-performance computing (HPC) cluster for multifunctional post-processing. The system supports multiple observation modes, including pulsars, transients, spectral lines, continuum, and very long baseline interferometry/baseband. High-performance shielded enclosures minimize electromagnetic radiation from digital devices in receiver cabins. A 100 Gb s −1 network enables massive data transfer to the HPC cluster for real-time processing, integrating radio frequency interference mitigation, raw voltage capture, and coordinated observation capabilities. The scalable architecture enables expansion via additional RFSoC and computing nodes. We present verification results including custom RFSoC development, electromagnetic compatibility design and test, software implementation, and successful pulsar observations, demonstrating the system’s readiness for scientific operations. This integrated solution significantly enhances signal fidelity while optimizing resource utilization for QTT’s advanced research capabilities.