Re-post from ANS-329
The satellite frequency coordination committee of the International Amateur Radio Union (IARU) on November 15 completed approval of frequency requests from the Chinese Amateur Satellite Group (CAMSAT) for a new amateur satellite to be launched next year.
CAS-11, a 6U CubeSat will include:
- HF/UHF – H/U Mode Linear Transponder, with a bandwidth of 15kHz downlink centered at 435.505 MHz, EIRP 24 dBm
Uplink 21.320 MHz +/- 7.5 kHz. - VHF/UHF – V/U Mode Linear Transponder, with a bandwidth of 30kHz downlink centered at 435.540 MHz, EIRP 24 dBm.
Uplink 145.860 MHz +/- 15 kHz. - VHF/UHF – V/U Mode FM Transponder, downlink at 435.600 MHz, EIRP 24 dBm
Uplink at 145.925 MHz - VHF/UHF – V/U Mode digital store-and-forward Transponder, downlink at 435.700 MHz, EIRP 24 dBm
Uplink at 145.895 MHz - UHF – CW Telemetry Beacon and
- UHF telemetry beacon using AX.25 4.8k/9.6kbps GMSK at 435.570 MHz, EIRP 23 dBm.
The above transponders and beacon will work 24/7 when the satellite power supply is sufficient. Amateur radio enthusiasts around the world can use it for two-way radio relay communication, data storage and forwarding communication, and receive satellite CW beacons.
The CAS-11 satellite will also be equipped with a 2.4 GHz multi-mode amateur radio satellite beacon transmitter, which is designed and built by university students, high school students and primary school students from Beijing Donggaodi Science and Technology Museum and Beijing University of Posts and Telecommunications under the guidance of CAMSAT. This is an unprecedented satellite project in China. It has brought opportunities for learning and practicing amateur radio and amateur satellites to students of all grades from elementary school to university, and promoted the application of amateur radio in space. This 2.4 GHz experimental beacon transmitter can switch to transmit five different modes of radio signals, and it will work continuously when the satellite is fully powered.
This project aims to cultivate students’ knowledge, skills and interests in amateur radio satellites. All transmission modes operate at 2.4 GHz, and the working modes are converted by the on-board computer program and ground remote control commands. It can work in the following modes: CW Telemetry Beacon, FT8 Telemetry Beacon, PPM Telemetry Beacon, or USB/SSTV Robot36, PD120 1. This beacon will transmit at 2405.500 MHz, EIRP 27 dBm.
CAS-11 carries three cameras, and the photos it takes are stored in the flash memory on the satellite. The builders have designed a simple remote control system based on DTMF commands. Amateur radio enthusiasts around the world can send DTMF commands to download the photo catalog and all photos taken by all cameras.
Anticipating a launch in September, 2025 into a 536 km polar orbit from Haiyang Sea Launch Platform, Shandong, China.
[ANS thanks IARU and Alan Kung, BA1DU, of CAMSAT for the above information.]