An Artificial Pulsar-signal Generator for Pulsar Search

Journal article, 2026

Pulsars, which are spinning neutron stars emit regular pulses and are essential to time-domain radio astronomy. Numerous observatories concentrate on detecting and researching faint pulsar signals, especially at radio frequencies. To enable rapid system verification, optimization, and troubleshooting, we have devised a cost-effective artificial pulsar signal generator utilizing an economical software-defined radio. These artificial signals are digitally synthesized with customizable parameters such as pulse period, dispersion measure, central frequency, bandwidth, sampling rate, pulse duration, and noise level. The central frequency can be set within 70 MHz-6 GHz, the instantaneous bandwidth up to 56 MHz, and the output power controlled via the gain setting, typically ranging from -20 to +10 dBm depending on frequency and gain. By incorporating frequency-dependent dispersion delays and Gaussian noise, these simulated signals can replicate the time and spectral features of actual pulsar emissions in a laboratory setting. Additionally, we performed single-dish experiments using the simulated pulsar signal and the 40 m radio telescope at Haoping Station, China. The resulting data were processed with standard pulsar signal analysis software. This demonstrates the signal generator's precision in fulfilling system calibration and verification needs for pulsar observations. As an affordable and compact device, the pulsar signal simulator enables researchers to design and experiment with new-generation pulsar backends anywhere and at any time without relying on a strong pulsar source. Moreover, it offers astronomers the opportunity to engage in pulsar-related educational activities using a small antenna at frequencies <6 GHz.