Add PY4 satellites to DB
Satellite name
Mission Name: PY4
There are four satellites: PY4-1, PY4-2, PY4-3, PY4-4. All have identical transmitter details and modulation parameters.
Description
PY4 is a low-cost, rapid-turn-around, four-satellite technology demonstration based on the open-source PyCubed avionics framework led by Carnegie Mellon University in collaboration with NASA SSTP. PY4 will demonstrate low SWaP-C SC-to-SC ranging, on-orbit topology determination, and coordinated measurements for future spacecraft swarm systems.
Image
Transmitter 1
Transmitter Name
UHF Beacon
Type
Transmitter
Service
Space Operation, Inter-satellite
Downlink Frequency
915.6 MHz
Downlink Mode
LoRa Parameter | Value |
---|---|
Center Frequency | 915.6 MHz |
Spreading Factor | 7 |
Bandwidth | 62.5 kHz |
Coding Rate | 4 (CR4/8) |
CRC | True |
Preamble Length | 8 Bytes |
Explicit Header? | True |
Low Datarate Optimize? | True |
Semtech Sync Word | 0x12 |
Packets are readily demodulated using common SDR tools such as SDRangel (confirmed, uses "Chirp Chat demod plugin"), GNUradio with LoRa demodulator, etc...
Dowlink Encoding
Beacons are raw bytes, with each beacon being 60 bytes. At launch beacons occur every 30 seconds.
- Simple webapp for decoding beacons: https://maholli.github.io/PY4_gs/
- Python script for decoding beacons (as well as running a simple standalone ground station): https://github.com/maholli/PY4_gs
To Do
-
Mission website (to be announced) -
NORAD catalog numbers (not yet assigned)