S-NET

 

Satellite Status NORAD Uplink Downlink Beacon Mode Callsign Reports Info IARU freq coord Telemetry Decoder
S-NET A
S-NET B
S-NET C
S-NET D
ACTIVE 43186 – 43189 435.950 1k2 FFSK DP0TBB
DP0TBC
DP0TBD
DP0TBE
latest report details YES

 

Networks of autonomous satellites that can communicate with each other: this is how the future of space travel should look and how it can be used in key areas such as communication, Earth observation, and the exploration of distant planets. With the “S-NET” mission, a world-wide unique flying association consisting of four micro-satellites will test new technologies for this purpose in space and prove their functionality. On February 1, 2018, at 3:07 pm Central European Time (CET), a Russian Soyuz-2-1a Fregat-M launcher launched from the Vostochny Space Station has launched the quartet into low earth orbit orbit. The technology mission of the TU Berlin is funded by the German Aerospace Center (DLR).

Downlink: 435.950 MHz, 1k2 FFSK

A space network of nanosatellites can achieve a higher local and temporal coverage of the earth’s surface through the targeted exchange of information among themselves than larger individual satellites. In addition, the possible failure of a single satellite within an autonomous network can be better compensated.

It is also possible to transmit data and signals much faster to the receiving stations on earth: In the previously customary satellite communication in low Earth orbit, resulting raw data are sent to a ground flight over ground stations with a delay of several hours to Earth, processed, archived and distributed. The delivery of data products usually takes one to several days. The new satellite constellations will make this possible in one to two hours. Especially in the prediction of natural disasters and in the emergency response would be a time gain through immediate processing in orbit and the communication from satellite to satellite to the nearest ground station a big win.

Amateur Radio Payload (will be activated later)

A selected S-Net satellite transmits a specific data packet at a fixed period (e.g., several times per minute) and over a particular area.

* the packet contains an sequence (140 bytes) in ASCII plain text (without encoding). Currently it says something like: “Hello World! This is S-NET: the intersatellite communication network of TU Berlin and DLR, vist also www.bit.ly/S-NET”)
* the transmitted byte sequence can be freely changed in advance in the memory of the satellite by the S-Net team

Every radio amateur can send his message to the S-Net team, together with the desire, when, over which area and how often it should be sent.


RF Spectrum – all four satellites active


Telemetry

Frame Structure

assignment SrcID to call sign

0 = SNET-A / COM0 -> DPOTBB
1 = SNET-A / COM1 -> DPOTBB
2 = SNET-B / COM0 -> DPOTBC
3 = SNET-B / COM1 -> DPOTBC
4 = SNET-C / COM0 -> DPOTBD
5 = SNET-C / COM1 -> DPOTBD
6 = SNET-D / COM0 -> DPOTBE
7 = SNET-D / COM1 -> DPOTBE

EPS telemetry packet

1: [S-NET] [12:35:57R]
[SrcId:0 DstId:127 FrCntTx:0 FrCntRx:0 SNR:15 AiTypeSrc:1 AiTypeDst:3 DfcId:0 Caller:0 Arq:0 PduTypeId:0 BchRq:0 Hailing:0 UdFl1:0 PduLength:62]
F3 50 34 E0 C0 01 20 36 9F 96 09 00 00 92 22 00 90 80 21 00 00 01 47 00 48 00 14 00 01 05 03 01 08 00 00 00 00 00 00 18 00 00 67 6A A6 2A 0A 07 08 04 04 10 00 00 07 01 00 00 00 00 D1 D3 
1: [S-NET] [12:36:01R]
[SrcId:0 DstId:127 FrCntTx:0 FrCntRx:0 SNR:15 AiTypeSrc:1 AiTypeDst:3 DfcId:0 Caller:0 Arq:0 PduTypeId:0 BchRq:0 Hailing:0 UdFl1:0 PduLength:62]
F3 50 2B A0 C0 01 20 36 7B 9C 09 00 00 92 22 00 90 80 21 00 00 01 47 00 48 00 14 00 01 05 03 01 1E 00 00 00 00 00 00 18 00 00 69 68 A8 2A 0A 05 08 02 04 10 00 00 07 01 00 00 00 00 67 D4 

SrcID = 0 -> 0 = SNET-A / COM0 -> DPOTBB

HDR parameter Value HDR parameter Value
Server time 2018-02-21 08:30:23.000000 UTC Type TM
FRSYNC 249152 Urgent NO
CRC 15896 RFU NO
FCID_MAJ FCIDM_EPS_HK_TELEMETRY CRC active YES
FCID_SUB EPS_STD_TM Multiframe NO
Data length 50 TT setting YES
Time tag 2018-02-21 08:30:23.000000 UTC TT active YES

 

Parameter Description Value Unit Parameter Description Value Unit
EPS_PGET_S00_CUR_SOLX_POS current X+ solar panel 15.56 mA EPS_PGET_S01_CUR_SOLX_NEG current X- solar panel 17.08 mA
EPS_PGET_S02_CUR_SOLY_POS current Y+ solar panel 0.3 mA EPS_PGET_S03_CUR_SOLY_NEG current Y- solar panel 192.72 mA
EPS_PGET_S04_CUR_SOLZ_POS current Z+ solar panel 3.06 mA EPS_PGET_S05_CUR_SOLZ_NEG current Z- solar panel 482.18 mA
EPS_PGET_S06_V_SOL main solar voltage (2,42V = 25V) 16520 mV EPS_PGET_S24_V_BAT0 voltage battery 0 (2.37V@12.6V) 12256 mV
EPS_PGET_S26_A_IN_CHARGER0 input current charger0 (2.5V@2500mA) 378.417 mA EPS_PGET_S25_A_OUT_CHARGER0 output current0 (2.5V@5000mA) 212.333 mA
EPS_PGET_S13_V_BAT1 voltage battery 1 (2.37V@12.6V) 12291.5 mV EPS_PGET_S23_A_IN_CHARGER1 input current charger1 (2.5V@2500mA) 326.5 mA
EPS_PGET_S14_A_OUT_CHARGER1 output current charger1 (2.5V@5000mA) 170.833 mA EPS_PGET_S22_V_SUM sum voltage unregulated bus (2.39V = 14V) 12052.5 mV
EPS_PGET_S44_V_3V3 voltage 3V3 bus (2.4V@3.6V) 3166.75 mV EPS_PGET_S45_V_5V voltage 5V bus (2.39V@5.5V) 5180 mV
THM_PGET_S31_TH_BAT0 temperature of battery 0 8 °C THM_PGET_S15_TH_BAT1 temperature of battery 1 9 °C
THM_PGET_TH_OBC temperature OBC external sensor (LMT85) 16 °C EPS_PGET_A_OBC current of OBC (2V@400mA) 55 mA
EPS_PGET_V_OBC voltage of OBC (2.048V@4.096V) 3257 mV EPS_PGET_S30_A_IN_BAT0 charge current battery 0 (2.5V@2500mA) 244.167 mA
EPS_PGET_S29_A_OUT_BAT0 discharge current battery 0 (2.5V@2500mA) 3.08333 mA EPS_PGET_S12_A_IN_BAT1 charge current battery 1 (2.5V@5A) 245.333 mA
EPS_PGET_S20_A_OUT_BAT1 discharge current battery 1 (2.5V@2500mA) 4.25 mA


RF spectrum


great thanks to Andy, UZ7HO for his continuous and competent work

1: [S-NET] [23:36:04R]
[SrcId:0 DstId:127 FrCntTx:0 FrCntRx:0 SNR:15 AiTypeSrc:1 AiTypeDst:3 DfcId:0 Caller:0 Arq:0 PduTypeId:0 BchRq:0 Hailing:0 UdFl1:0 PduLength:62]
F3 50 18 F0 C0 01 20 36 E7 0D 09 00 00 92 22 00 90 80 21 00 00 01 47 00 48 00 14 00 01 05 03 01 1C 00 00 00 00 00 00 17 00 00 65 6C 9C 2A 0B 08 09 04 04 10 00 00 07 01 00 00 00 00 25 C6
1: [S-NET] [23:36:06R]
[SrcId:0 DstId:127 FrCntTx:0 FrCntRx:0 SNR:15 AiTypeSrc:1 AiTypeDst:3 DfcId:0 Caller:0 Arq:0 PduTypeId:0 BchRq:0 Hailing:0 UdFl1:0 PduLength:62]
F3 50 25 B0 C0 01 20 36 C3 13 09 00 00 92 22 00 90 80 21 00 00 01 47 00 48 00 14 00 01 05 03 01 32 00 00 00 00 00 00 17 00 00 68 69 A8 2A 0B 07 09 04 04 10 00 00 07 01 00 00 00 00 BB C6
1: [S-NET] [23:36:11R]
[SrcId:0 DstId:127 FrCntTx:0 FrCntRx:0 SNR:15 AiTypeSrc:1 AiTypeDst:3 DfcId:0 Caller:0 Arq:0 PduTypeId:0 BchRq:0 Hailing:0 UdFl1:0 PduLength:62]
F3 50 2D E0 C0 01 20 36 63 23 09 00 00 92 22 00 90 80 21 00 00 01 47 00 48 00 14 00 01 05 03 01 02 00 00 00 00 00 00 17 00 00 67 69 3F 2A 0B 08 09 05 04 10 00 00 07 01 00 00 00 00 4B C8



great thanks also to Dani, EA4GPZ for his continously work on gr-satellites

http://destevez.net/2018/03/decoding-s-net/


Links

http://www.raumfahrttechnik.tu-berlin.de/menue/forschung/aktuelle_projekte/s_net/parameter/en/parameter/en/parameter/en/
http://destevez.net/2018/03/decoding-s-net/
https://www.youtube.com/watch?v=jfk1yyKtU9A