TMPOB: A Real-Time Pulsar Observation Backend for the Tianma Radio Telescope

Abstract

Pulsar observations require backend systems capable of converting telescope signals into data products suitable for scientific analysis while supporting high time resolution, coherent dedispersion, and multiple observing modes. We present the development and performance evaluation of the Tianma Pulsar Observation Backend (TMPOB), a heterogeneous RFSoC-CPU-GPU system that supports fold, search, and baseband modes. In fold and search modes, TMPOB provides a maximum observing bandwidth of 512 MHz, with data streams processed at an aggregate payload rate of up to 32.8 Gb s -1 . A unified control framework enables automated operation, remote management, and real-time monitoring. We evaluated TMPOB using S- and X-band observations conducted with the Tianma Radio Telescope (TMRT) between February and September 2025. In fold mode, TMPOB maintained a stable 10 s output cadence during long-duration observations, with a mean end-to-end latency of 8.638 s in short-term tests. Repeated observations conducted over a three-month campaign demonstrated reproducible short-term timing-residual performance, and an X-band observation successfully detected pulsars across the full bandwidth. Search and baseband data were further verified using standard pulsar processing software. These results demonstrate that TMPOB is a robust digital backend for broadband pulsar observations with the TMRT.