The purpose of the communications system is to downlink science and housekeeping data and uplink commands. Therefore, it includes both the space segment and the ground segment. Useful pointers:
- Frequency Allocations
- Communication Architecture for MASSIVE Missions (includes task list)
- New ground station at NTNU
- Specifications of Available Ground Stations
- Frequency trade-off analysis - Available products
- How to apply for frequencies
TRANSMITTER ARCHITECTURE
RECEIVER ARCHITECTURE
GROUND STATIONS SPECIFICATIONS
- KSAT
Data acquisition-High data rate modem
| Specifications | Units | Values |
|---|---|---|
| Maximum sampling frequency | [Msps] | 600 |
| Maximum bandwidth | [MHz] | 75 |
| Modulation schemes | - | BPSK,QPSK, SQPSK, 8PSK,16APSK, 16QAM,32 APSK |
| FEC techniques | - | Convolutional, Reed-Solomon, LDPC |
Antenna performance
S-band
| Specifications | Units | Downlink | Uplink |
|---|---|---|---|
| Reflector size | [m] | 3.7 | |
| Frequency band | [MHz] | 2200-2300 | 2025-2110 |
| G/T | [dB/K] | 12.6 | - |
| Polarisation | - | RHCP/LHCP | |
| EIRP | [dBW] | - | 44.8 |
TT&C services
| Specifications | Units | Downlink | Uplink |
|---|---|---|---|
| Bandwidth | [MHz] | 5 | |
| Sampling frequency | [Msps] | 5 | 1 |
| Modulation schemes | - | PCM/FM, FSK, BPSK, QPSK, OQPSK | |
| Coding/decoding techniques | - | Viterbi decoding, Reed Solomon, Convolutional Encoding | |
- ISIS
| S-band | VHF | UHF | ||||
| Specifications | Units | Downlink | Downlink | Uplink | Downlink | Uplink |
|---|---|---|---|---|---|---|
| Antenna size | [m] | 2 | 3.2 | 3 | ||
| Frequency band | [MHz] | 2200-2500 | 143 – 148 | 432 – 440 | ||
| Antenna beamwidth | [°] | 5.1 | 52 | 30 | ||
| G/T | [dB/K] | 4.9 | - | - | - | - |
| Antenna gain | [dB] | 31.35 | 13.2 | 16.3 | ||
| Overall noise figure | [dB] | 15 | 1.6 | - | 2 | - |
| Antenna polarisation | - | RHCP/LHCP | RHCP-LHCP | RHCP-LHCP | ||
| Data rates | [kbps] | 14.4 – 115.2 | 1.2 – 9.6 | 1.2, 2.4, 4.8, 9.6 | 1.2 – 9.6 | 1.2, 2.4, 4.8, 9.6 |
| RF output power | [W] | - | - | 100 | - | 120 |
| Modulation schemes | - | - | Raised-Cosine BPSK, AFSK, FSK, GMSK. | AFSK, FSK, BPSK | Raised-Cosine BPSK, AFSK, FSK, GMSK. | AFSK, FSK, BPSK |
| Communications protocol | - | - | AX.25 | AX.25 | AX.25 | AX.25 |
...