The cubesat D-Star One, the first German private cubesat will ship a D-Star communication capability should be launched on November 28, 2017.
D-Star One is a 3U CubeSat which is equipped with four identical radio modules with D-Star capabilities, all being operated in a half-duplex mode.
Two modules are used for telemetry and telecomand and operate on identical frequencies. Telemetry can be received on 435,7 MHz, the format will be disclosed after launch. Both modules receive, and both modules answer. To prevent information loss, they answer after each other. So each telemetry frame is repeated twice. Both modules have a D-Star Voice-Message Beacon, but it is only activated for one module during LEOP. The Beacon is repeated once in a minute.
The other two modules are dedicated to the radio amateur community. Both modules have the same frequencies, so one of them will be powered down as long as the other one shows no degradation effects. The downlink frequency is 435.525 MHz and the uplink frequency is 437.325 MHz. Also here half-duplex mode is applied. The modules are configured to work as D-Star repeaters, so they retranslate the received d-star frames on the downlink frequency. They also have a D-Star voice beacon signal.
All modules are operated in a power save mode. This means that they are in idle for 40 seconds and then in receive mode for 20 seconds. Once a signal has been received, the modules switch to receive mode for five minutes. So it might be necessary to „ping“ the satellite a couple of times until an answer is received.
The radio characteristics are:
- DStar
- Mount frequency: 437.325MHz
- Frequency of descent: 435.525MHz
- RF power: 800mW
- Code: DGP1GOS
- Telemetry
- Frequency of descent: 435.525MHz
Orbit parameters and TLE:
The target orbit for D-Star ONE spacecraft is a circular sun synchronous orbit with an altitude of approx. 585km
Prelimenary TLE details are here, updates comming.
D-Star ONE 1 99999U 17332.34739815 .00000000 00000-0 00000-0 0 00004
2 99999 097.7600 140.1500 0012940 103.0900 156.2816 14.93956737000011
Launch Time from Baikonur cosmodrome ( Time in UTC )
Tomorrows (based on UTC) live launch information Maybe live coverage via tv-tsenki.com/live.php
A WWW site is being set up with additional information: http://www.d-star.one
Links :
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