Reception
We are inviting all radio-amateurs and satellite enthusiasts around the world to help us receive QUBIK twins while in orbit. This is what you need to know about reception of QUBIK signals:
Beacons
QUBIK-1 and QUBIK-2 will be beaconing 30 minutes after deployment at the same frequency (this is part of the experimentation) 435.240 Mhz.
The satellites are programmed with a specific beaconing pattern to enable various Experiments for LEOP orbit determination and identification.
The default beaconing pattern is as follows:
PA |
Power |
Telemetry Type |
Modulation |
Encoding |
Baud |
ms |
sec delay |
||
---|---|---|---|---|---|---|---|---|---|
1 |
1 |
-2 |
Basic |
GFSK |
RS |
9600 |
220 |
30 |
|
2 |
1 |
-2 |
Basic |
BPSK-RES |
CC12RS |
9600 |
1300 |
30 |
|
3 |
1 |
-2 |
Basic |
GFSK |
RS |
9600 |
220 |
30 |
|
4 |
1 |
-2 |
Basic |
GFSK |
CC12RS |
9600 |
400 |
30 |
|
5 |
1 |
-2 |
Basic |
GFSK |
RS |
9600 |
220 |
30 |
|
6 |
1 |
-2 |
Basic |
BPSK-RES |
CC12RS |
9600 |
1300 |
30 |
|
7 |
1 |
-2 |
Basic |
GFSK |
RS |
9600 |
220 |
30 |
|
8 |
1 |
-2 |
Basic |
GFSK |
CC12RS |
9600 |
400 |
30 |
|
9 |
1 |
-2 |
Basic |
GFSK |
RS |
9600 |
220 |
30 |
|
10 |
1 |
-2 |
Basic |
BPSK-RES |
CC12RS |
9600 |
1300 |
30 |
|
11 |
1 |
-2 |
Basic |
GFSK |
RS |
9600 |
220 |
30 |
|
12 |
0 |
15 |
Basic |
RILDOS |
RAW |
125000 |
2500 |
30 |
All modulations regardless of their encoding and baud rate are CCSDS TM Space Data Link packets with a specific payload (the actual telemetry).
The Telemetry structure is as follows:
Category |
Field |
Details |
Size |
Unit |
|
---|---|---|---|---|---|
Power |
Current |
Instantaneous |
16 |
s2 |
mA |
Power |
Voltage |
Instantaneous |
16 |
u2 |
mV |
Power |
Die Temperature |
Instantaneous |
8 |
s1 |
C |
Power |
Battery Temperature |
Instantaneous |
8 |
s1 |
C |
Power |
Current |
Min |
16 |
s2 |
mA |
Power |
Voltage |
Min |
16 |
u2 |
mV |
Power |
Battery Temperature |
Min |
8 |
s1 |
C |
Power |
Current |
Max |
16 |
s2 |
mA |
Power |
Voltage |
Max |
16 |
u2 |
mV |
Power |
Battery Temperature |
Max |
8 |
s1 |
C |
Power |
Current |
Average |
16 |
s2 |
mA |
Power |
Voltage |
Average |
16 |
u2 |
mV |
Power |
Battery Temperature |
Average |
8 |
s1 |
C |
Power |
Time to empty |
16 |
u2 |
min |
|
Power |
Remaining capacity |
16 |
s2 |
mAh |
|
Power |
Full capacity |
16 |
s2 |
mAh |
|
Power |
State of charge (%) |
8 |
s1 |
% |
|
Antenna |
Antenna Deploy Test voltage |
Acquired once on antenna deployment |
16 |
s2 |
mV |
Antenna |
Antenna Deploy Test current |
Acquired once on antenna deployment |
16 |
s2 |
mA |
Antenna |
Antenna Deploy Test result |
Acquired once on antenna deployment |
8 |
u1 |
n/a |
Antenna |
Antenna Deploy average voltage |
Acquired once on antenna deployment |
16 |
s2 |
mV |
Antenna |
Antenna Deploy average current |
Acquired once on antenna deployment |
16 |
s2 |
mA |
Antenna |
Antenna Deploy duration |
Acquired once on antenna deployment |
8 |
u1 |
s |
Antenna |
Antenna Deploy status |
Acquired once on antenna deployment |
8 |
u1 |
n/a |
Antenna |
Antenna Deploy retries |
Acquired during antenna deployment |
8 |
u1 |
n/a |
MCU |
Uptime |
32 |
u4 |
secs |
|
MCU |
Internal Temperature |
8 |
s1 |
C |
|
MCU |
RTC Battery Voltage |
16 |
u2 |
mV |
|
Operational |
First Deploy |
8 |
u1 |
n/a |
|
Operational |
Antenna first Deploy |
8 |
u1 |
n/a |
|
Statistics |
Reasons of reset |
8 |
u1 |
||
Statistics |
Dropped Frames |
16 |
u2 |
||
Statistics |
low_power_counter |
16 |
u2 |
||
Statistics |
independent_watchdog_counter |
16 |
u2 |
||
Statistics |
software_counter |
16 |
u2 |
||
Statistics |
brownout_counter |
16 |
u2 |
||
Status |
Power Save |
8 |
u1 |
n/a |
|
Status |
Power Monitor Fail |
8 |
u1 |
n/a |
|
OSDLP |
CLCW per VC |
160 |
20 |
||
Radio |
Tx Frames |
16 |
u2 |
||
Radio |
Rx Frames |
16 |
u2 |
||
Radio |
Rx corrected bits |
32 |
u4 |
||
Radio |
RSSI |
8 |
s1 |
dB |
|
Radio |
Frequency tracking |
16 |
s2 |
||
Radio |
AGC |
8 |
s1 |
||
Radio |
Data rate Tracking |
32 |
s4 |
||
Radio |
Phase Tracking |
16 |
s2 |
||
Radio |
RF Freq Tracking |
32 |
s4 |
||
Radio |
Rx-Tx turnaround |
16 |
u2 |
ms |
The kaitai struct for the whole PDU can be found here .
How to receive
The easiest way to receive is by setting up a SatNOGS station. SatNOGS is already setup for QUBIK tracking, demodulating, decoding and forwarding to the appropriate dashboard at dashboards.satnogs.org . Learn how to setup a SatNOGS station.