Is anybody else working on decoding the Falcon 9 telemetry? - Page 1
Forum section: electronics / general

author: hamster_nz
author_rank: Super Contributor
timestamp: March 28, 2021, 09:28:52 pm
content: I'm working on it to learn a little more SDR techniques, and to understand a bit more about telemetry standards in general..Mine is more of a programming project than a using 'GNUradio" or "satdump"...

author: hamster_nz
author_rank: Super Contributor
timestamp: March 31, 2021, 10:58:58 am
content: I'm getting somewhere... can demodulate the I+Q signal, recover the bits, find the framing, and remove the pseudo-random scrambling.Can now see the GPS debug text... now need to learn a lot more about the CCSDS protocol.Code:1ACFFC1D 460688452 ( 2558:0) .j...}.....1....p...$'.....Kx4016> so.ution tnw:37423.9005.08231, w.:2149.1299752624367933861> 14 PLL stress.1299752644.E0 6A A4 00 B0 7D 01 17 CE 08 00 31 03 03 02 00 70 12 09 A6 24 27 09 12 1C 00 DA 4B 78 34 30 31 36 3E 20 73 6F EC 75 74--1ACFFC1D 482124492 ( 1279:0) .....}.....2....p...!...K..O.is(valid: 1) for GPS L1CA 32, fi:14400.1299752629281687460> New ephemeris(valid: 1) for GPSE0 AC 18 00 F0 7D 01 17 FE 08 00 32 03 03 02 00 70 12 09 A6 21 8C BF EF 4B 00 DE 4F 9B 69 73 28 76 61 6C 69 64 3A 20 31--1ACFFC1D 484262980 ( 1279:0) .....}.....2....p...!...*..P.GPS L1CA 28, fi:14400.1299752629286462898> New ephemeris(valid: 1) for GPS L1CA 14, fi:1440E0 B2 A0 00 F0 7D 01 17 FE 08 00 32 03 03 02 00 70 12 09 A6 21 B0 84 83 2A 00 DE 50 C7 47 50 53 20 4C 31 43 41 20 32 38--1ACFFC1D 486411700 ( 1279:0) ..0..}.....2....p...!.G....Q.4400.1299752630899779716> Track: [21e 22e 25s 01s 14e 32s 20s 23s 10s . . $. . . * .E0 B9 30 00 F0 7D 01 17 FE 08 00 32 03 03 02 00 70 12 09 A6 21 D4 47 EE 0D 00 DE 51 F3 34 34 30 30 0A 31 32 39 39 37 35--1ACFFC1D 499263092 ( 1279:0) ..0..<.....2..../..."......T.129.752635203819476> 14 PLL stress.#....."...........`].'.......H...."...........`...Z.+.E0 E0 30 00 F0 3C 01 17 FE 08 00 32 03 03 02 00 2F 12 09 A6 22 AA D7 1E A9 00 DE 54 04 31 32 39 B9 37 35 32 36 33 35 32--1ACFFC1D 499979332 ( 1279:0) .....Z.....2....M...".._...T'1299752635298822666> Channel 17, SID 2 got TOW H 12290: 354.5208.5....."...............Z..E0 E2 A0 00 F0 5A 01 17 FE 08 00 32 03 03 02 00 4D 12 09 A6 22 B6 C2 5F 09 00 DE 54 27 31 32 39 39 37 35 32 36 33 35 32--1ACFFC1D 537837732 ( 1279:0) .V@..}.....2....p...%..t_..W.1299752645900141511> 23 low CN0 too long, dropping (@ 77830231096000000.000).12997526459012E0 56 40 00 F0 7D 01 17 FE 08 00 32 03 03 02 00 70 12 09 A6 25 2E A1 74 5F 00 DE 57 98 31 32 39 39 37 35 32 36 34 35 39--1ACFFC1D 587831284 ( 1279:0) .....}.....2....p...(q.....^.for GPS L1CA 10, fi:14400.1299752659280612710> New ephemeris(valid: 1) for GPS L1CA 23, fi:E0 EE F0 00 F0 7D 01 17 FE 08 00 32 03 03 02 00 70 12 09 A6 28 71 0B BA D1 00 DE 5E C9 66 6F 72 20 47 50 53 20 4C 31 43--1ACFFC1D 588547524 ( 1279:0) .. ....7a.].'..1A.P...}.....2....p...(|....._-9752659280812646> New ephemeris(valid: 1) for GPS L1CA 13, fi:14400.129975E0 F1 20 11 A5 DB 99 37 61 18 5D EE 27 AA 15 31 41 0E 50 12 FD F0 7D 01 17 FE 08 00 32 03 03 02 00 70 12 09 A6 28 7C EE--1ACFFC1D 589263764 ( 1279:0) ..P..}.....2....p...(..t..._.is(valid: 1) for GPS L1CA 25, fi:14400.1299752659281874400> New ephemeris(valid: 1) for GPSE0 F3 50 00 F0 7D 01 17 FE 08 00 32 03 03 02 00 70 12 09 A6 28 88 EA 74 2E 00 DE 5F 91 69 73 28 76 61 6C 69 64 3A 20 31--

author: nali
author_rank: Frequent Contributor
timestamp: March 31, 2021, 12:02:02 pm
content: I saw that Scott Manley did a video on the subjectLink from his descriptionhttps://www.r00t.cz/Sats/Falcon9

author: DiTBho
author_rank: Super Contributor
timestamp: March 31, 2021, 02:11:26 pm
content: I don't work with rockets but I have recently developed my own protocol. It's simple, but it uses symmetric encryption (Blowfish) at the transport layer.

author: hamster_nz
author_rank: Super Contributor
timestamp: March 31, 2021, 08:24:52 pm
content: Quote from: nali on March 31, 2021, 12:02:02 pmAh! That answers the missing bit I was up to... they are using custom framing embedder in the CCSDS stream.

author: coromonadalix
author_rank: Super Contributor
timestamp: April 09, 2021, 05:49:47 pm
content: I think they have encrypted the telemetry ....