1 Fast alert downlink

Upon detection of a transient source, its alert information will be downlinked to the ground segment with a latency about 10 minutes or so. The alert data includes the coordinates, flux, spectral hardness ratio, and possibly a simple lightcurve of the source. To do this, the Beidou system will be utilised by taking advantage of its short text message capability and global coverage. To enhance the alert capability to transmit more of the quick-look data of transients, the VHF network system of the CNES (France), which is built for the Chinese-French SVOM mission, will be used via collaboration. The quick-look data will be helpful for the assessment and diagnostics of the transients.

2.ToO uplink

EP satellite is able to maneuver in-orbit to set the FXT pointing to transient astronautic objects found and located by other ground-based facilities, via uplinked telecommands from ground stations. The near-real-time telecommands uplinked is realized through the short-message-broadcast service provided by Beidou navigation system, with the telemetry telecommand system as an alternative backup.