The two initial frequency band groups specified by 5G NTN are called FR1 and FR2.
There are two specified 5G NR bands in NTN FR1: n255 (L-Band) and n256 (S-Band).
Echostar also appears to be in the process of setting up a separate 28-LEO-sattelite constellation just for NTN, where the actual gNB (or at least part of it) is in the sattelite itself. That's not deployed as of now (2023).
The setup was not ideal since the antenna was not the most appropriate (linear polarization while the sat should be LHCP) and the view is also partially obstructed. A good setup should be able to provide higher signal strength.
There seems to be 4 carriers that look like 4G/LTE NBIoT.
And then we can decode it with `npdsch_ue` which will also save the MIB/SIB into a pcap :
RF device 'UHD' successfully opened
Set RX gain: 65.0 dB
Set RX freq: 2198.400000 MHz
Setting sampling rate 1.92 MHz
Actual sampling rate 1.92 MHz
[INFO]: Stopping RF and flushing buffer...
[INFO]: Generating NRS for n_id_ncell=11
[INFO]:
Entering main loop...
[INFO]: Realigning frame, reading 13591 sampleste: 0
[INFO]: Successfully decoded NPBCH sfn_offset=0te: 1
[INFO]: Time offset adjustment: -1 samples (-0.09), mean SFO: -1.80 Hz, -0.00900 samples/10-sf, ema=0.100000, length=10
[INFO]: Successfully decoded NPBCH sfn_offset=0
[INFO]: MIB-NB decoded: 1 with offset 0
MIB received (CFO: +1.19 kHz)
- N_id_ncell: 11
- Release: r14
- Nof ports: 1
- SFN: 64
- HFN (2 LSB): 0
- Sched. Info SIB1 0
- First frame 48
- #repetitions 4
- TBS 208
- System Info Val 0
- AC barring No
- Operating mode Standalone
[INFO]: Init NPDCCH: Max bits: 336, 0 ports.
[INFO]: Init NPDSCH: max_re's: 1600
[INFO]: Generating NRS for n_id_ncell=11
[INFO]: NPDSCH: Cell config n_id_ncell=11, 1 ports, 1 PRBs base cell, max_symbols: 1600
[INFO]: 16 DL SIB1-NB SFNs:
[48, 112, 176, 240, 304, 368, 432, 496, 560, 624, 688, 752, 816, 880, 944, 1008, ];
[INFO]: 64.x: Activated SIB1 decoding in sfn=304
[INFO]: Time offset adjustment: -1 samples (-0.10), mean SFO: -2.56 Hz, -0.01282 samples/10-sf, ema=0.100000, length=10
[INFO]: Time offset adjustment: -1 samples (-0.09), mean SFO: -3.41 Hz, -0.01707 samples/10-sf, ema=0.100000, length=10
[INFO]: 304.4: NPDSCH processing sf_idx=1/8 rep=1/4 tot=1/32
[INFO]: 306.4: NPDSCH processing sf_idx=2/8 rep=1/4 tot=2/32
[INFO]: 308.4: NPDSCH processing sf_idx=3/8 rep=1/4 tot=3/32
[INFO]: 310.4: NPDSCH processing sf_idx=4/8 rep=1/4 tot=4/32
[INFO]: 312.4: NPDSCH processing sf_idx=5/8 rep=1/4 tot=5/32
[INFO]: 314.4: NPDSCH processing sf_idx=6/8 rep=1/4 tot=6/32
[INFO]: 316.4: NPDSCH processing sf_idx=7/8 rep=1/4 tot=7/32
[INFO]: 318.4: NPDSCH processing sf_idx=8/8 rep=1/4 tot=8/32
[INFO]: 318.4: Trying to decode NPDSCH with 8 subframe(s).
[INFO]: 318.x: Decoding NPDSCH: RNTI: 0xffff, Mod QPSK, TBS: 208, NofSymbols: 8 * 160, NofBitsE: 8 * 320
[INFO]: Decoded Message:
[40 50 80 c8 0a 62 1f 56 02 1b 11 60 00 ff 0e 05 60 55 88 4c 80 00 00 00 00 00 ];
SIB1 received
[INFO]: 318.x: Activated SIB2 reception in hfn=32, sfn=512
[INFO]: Time offset adjustment: -1 samples (-0.10), mean SFO: -3.55 Hz, -0.01775 samples/10-sf, ema=0.100000, length=10
[INFO]: Time offset adjustment: -1 samples (-0.10), mean SFO: -3.60 Hz, -0.01799 samples/10-sf, ema=0.100000, length=10
[INFO]: 512.1: NPDSCH processing sf_idx=1/8 rep=1/1 tot=1/8
[INFO]: 512.2: NPDSCH processing sf_idx=2/8 rep=1/1 tot=2/8
[INFO]: 512.3: NPDSCH processing sf_idx=3/8 rep=1/1 tot=3/8
[INFO]: 512.4: NPDSCH processing sf_idx=4/8 rep=1/1 tot=4/8
[INFO]: 512.6: NPDSCH processing sf_idx=5/8 rep=1/1 tot=5/8
[INFO]: 512.7: NPDSCH processing sf_idx=6/8 rep=1/1 tot=6/8
[INFO]: 512.8: NPDSCH processing sf_idx=7/8 rep=1/1 tot=7/8
[INFO]: 513.1: NPDSCH processing sf_idx=8/8 rep=1/1 tot=8/8
[INFO]: 513.1: Trying to decode NPDSCH with 8 subframe(s).
[INFO]: 513.x: Decoding NPDSCH: RNTI: 0xffff, Mod QPSK, TBS: 440, NofSymbols: 8 * 160, NofBitsE: 8 * 320
[INFO]: Decoded Message:
[00 42 40 3e 7f ca 69 50 f0 cc bb 81 00 5d 88 50 40 61 96 ee c0 1c 1a 00 e0 42 8d 81 f3 31 91 4b 04 37 8f 34 45 d4 00 6b 00 1c 40 86 1f c6 ac 7b fe 25 00 01 d1 30 00 ];
SIB2 received
[INFO]: 513.x: Activated SIB1 decoding in sfn=560
[INFO]: Time offset adjustment: -1 samples (-0.07), mean SFO: -2.97 Hz, -0.01487 samples/10-sf, ema=0.100000, length=10DSCH-Rate: 0.12 kbit/ss
[INFO]: 560.4: NPDSCH processing sf_idx=1/8 rep=1/4 tot=1/32 NPDCCH detected: 0, NPDSCH-BLER: 0.00% (0 of total 2), NPDSCH-Rate: 0.12 kbit/s
[INFO]: 562.4: NPDSCH processing sf_idx=2/8 rep=1/4 tot=2/32 NPDCCH detected: 0, NPDSCH-BLER: 0.00% (0 of total 3), NPDSCH-Rate: 0.12 kbit/s
[INFO]: 564.4: NPDSCH processing sf_idx=3/8 rep=1/4 tot=3/32 NPDCCH detected: 0, NPDSCH-BLER: 0.00% (0 of total 3), NPDSCH-Rate: 0.11 kbit/s
[INFO]: 566.4: NPDSCH processing sf_idx=4/8 rep=1/4 tot=4/32 NPDCCH detected: 0, NPDSCH-BLER: 0.00% (0 of total 3), NPDSCH-Rate: 0.11 kbit/s
[INFO]: 568.4: NPDSCH processing sf_idx=5/8 rep=1/4 tot=5/32 NPDCCH detected: 0, NPDSCH-BLER: 0.00% (0 of total 3), NPDSCH-Rate: 0.11 kbit/s
[INFO]: 570.4: NPDSCH processing sf_idx=6/8 rep=1/4 tot=6/32 NPDCCH detected: 0, NPDSCH-BLER: 0.00% (0 of total 3), NPDSCH-Rate: 0.11 kbit/s
[INFO]: 572.4: NPDSCH processing sf_idx=7/8 rep=1/4 tot=7/32 NPDCCH detected: 0, NPDSCH-BLER: 0.00% (0 of total 3), NPDSCH-Rate: 0.11 kbit/s
[INFO]: 574.4: NPDSCH processing sf_idx=8/8 rep=1/4 tot=8/32 NPDCCH detected: 0, NPDSCH-BLER: 0.00% (0 of total 3), NPDSCH-Rate: 0.11 kbit/s
[INFO]: 574.4: Trying to decode NPDSCH with 8 subframe(s).
[INFO]: 574.x: Decoding NPDSCH: RNTI: 0xffff, Mod QPSK, TBS: 208, NofSymbols: 8 * 160, NofBitsE: 8 * 320
[INFO]: Decoded Message:
[40 50 80 c8 0a 62 1f 56 02 1b 11 60 00 ff 0e 05 60 55 88 4c 80 00 00 00 00 00 ];
[INFO]: 574.x: Activated SIB1 decoding in sfn=816
[INFO]: Time offset adjustment: -1 samples (-0.06), mean SFO: -2.24 Hz, -0.01118 samples/10-sf, ema=0.100000, length=10DSCH-Rate: 0.14 kbit/s
[INFO]: Time offset adjustment: -1 samples (-0.09), mean SFO: -2.76 Hz, -0.01380 samples/10-sf, ema=0.100000, length=10DSCH-Rate: 0.12 kbit/s
[INFO]: 816.4: NPDSCH processing sf_idx=1/8 rep=1/4 tot=1/32 NPDCCH detected: 0, NPDSCH-BLER: 0.00% (0 of total 3), NPDSCH-Rate: 0.10 kbit/s
[INFO]: 818.4: NPDSCH processing sf_idx=2/8 rep=1/4 tot=2/32 NPDCCH detected: 0, NPDSCH-BLER: 0.00% (0 of total 4), NPDSCH-Rate: 0.10 kbit/s
[INFO]: Time offset adjustment: -1 samples (-0.05), mean SFO: -2.07 Hz, -0.01035 samples/10-sf, ema=0.100000, length=10DSCH-Rate: 0.10 kbit/s
[INFO]: 820.4: NPDSCH processing sf_idx=3/8 rep=1/4 tot=3/32 NPDCCH detected: 0, NPDSCH-BLER: 0.00% (0 of total 4), NPDSCH-Rate: 0.10 kbit/s
[INFO]: 822.4: NPDSCH processing sf_idx=4/8 rep=1/4 tot=4/32 NPDCCH detected: 0, NPDSCH-BLER: 0.00% (0 of total 4), NPDSCH-Rate: 0.10 kbit/s
[INFO]: 824.4: NPDSCH processing sf_idx=5/8 rep=1/4 tot=5/32 NPDCCH detected: 0, NPDSCH-BLER: 0.00% (0 of total 4), NPDSCH-Rate: 0.10 kbit/s
[INFO]: 826.4: NPDSCH processing sf_idx=6/8 rep=1/4 tot=6/32 NPDCCH detected: 0, NPDSCH-BLER: 0.00% (0 of total 4), NPDSCH-Rate: 0.10 kbit/s
[INFO]: 828.4: NPDSCH processing sf_idx=7/8 rep=1/4 tot=7/32 NPDCCH detected: 0, NPDSCH-BLER: 0.00% (0 of total 4), NPDSCH-Rate: 0.10 kbit/s
[INFO]: 830.4: NPDSCH processing sf_idx=8/8 rep=1/4 tot=8/32 NPDCCH detected: 0, NPDSCH-BLER: 0.00% (0 of total 4), NPDSCH-Rate: 0.10 kbit/s
[INFO]: 830.4: Trying to decode NPDSCH with 8 subframe(s).
[INFO]: 830.x: Decoding NPDSCH: RNTI: 0xffff, Mod QPSK, TBS: 208, NofSymbols: 8 * 160, NofBitsE: 8 * 320
[INFO]: Decoded Message:
[40 50 80 c8 0a 62 1f 56 02 1b 11 60 00 ff 0e 05 60 55 88 4c 80 00 00 00 00 00 ];
[INFO]: 830.x: Activated SIB1 decoding in sfn=48
[INFO]: Time offset adjustment: -1 samples (-0.05), mean SFO: -1.72 Hz, -0.00861 samples/10-sf, ema=0.100000, length=10DSCH-Rate: 0.12 kbit/s
CFO: +1.32 kHz, RSRP: -3.2 dBm SNR: 7.8 dB, RSRQ: -3.9 dB, NPDCCH detected: 0, NPDSCH-BLER: 0.00% (0 of total 4), NPDSCH-Rate: 0.10 kbit/s
[INFO]: Time offset adjustment: -1 samples (-0.10), mean SFO: -2.90 Hz, -0.01450 samples/10-sf, ema=0.100000, length=10DSCH-Rate: 0.00 kbit/s
[INFO]: 48.4: NPDSCH processing sf_idx=1/8 rep=1/4 tot=1/32, NPDCCH detected: 0, NPDSCH-BLER: -nan% (0 of total 0), NPDSCH-Rate: 0.00 kbit/s
[INFO]: 50.4: NPDSCH processing sf_idx=2/8 rep=1/4 tot=2/32, NPDCCH detected: 0, NPDSCH-BLER: 0.00% (0 of total 1), NPDSCH-Rate: 0.00 kbit/s
[INFO]: 52.4: NPDSCH processing sf_idx=3/8 rep=1/4 tot=3/32, NPDCCH detected: 0, NPDSCH-BLER: 0.00% (0 of total 1), NPDSCH-Rate: 0.00 kbit/s
[INFO]: 54.4: NPDSCH processing sf_idx=4/8 rep=1/4 tot=4/32, NPDCCH detected: 0, NPDSCH-BLER: 0.00% (0 of total 1), NPDSCH-Rate: 0.00 kbit/s
[INFO]: 56.4: NPDSCH processing sf_idx=5/8 rep=1/4 tot=5/32, NPDCCH detected: 0, NPDSCH-BLER: 0.00% (0 of total 1), NPDSCH-Rate: 0.00 kbit/s
[INFO]: 58.4: NPDSCH processing sf_idx=6/8 rep=1/4 tot=6/32, NPDCCH detected: 0, NPDSCH-BLER: 0.00% (0 of total 1), NPDSCH-Rate: 0.00 kbit/s
[INFO]: 60.4: NPDSCH processing sf_idx=7/8 rep=1/4 tot=7/32, NPDCCH detected: 0, NPDSCH-BLER: 0.00% (0 of total 1), NPDSCH-Rate: 0.00 kbit/s
[INFO]: 62.4: NPDSCH processing sf_idx=8/8 rep=1/4 tot=8/32, NPDCCH detected: 0, NPDSCH-BLER: 0.00% (0 of total 1), NPDSCH-Rate: 0.00 kbit/s
[INFO]: 62.4: Trying to decode NPDSCH with 8 subframe(s).
[INFO]: 62.x: Decoding NPDSCH: RNTI: 0xffff, Mod QPSK, TBS: 208, NofSymbols: 8 * 160, NofBitsE: 8 * 320
[INFO]: Decoded Message:
[40 50 80 c8 0a 62 1f 56 02 1b 11 60 00 ff 0e 05 60 55 88 4c 80 00 00 00 00 00 ];
[INFO]: 62.x: Activated SIB1 decoding in sfn=304
[INFO]: Time offset adjustment: -1 samples (-0.07), mean SFO: -2.52 Hz, -0.01262 samples/10-sf, ema=0.100000, length=10DSCH-Rate: 0.22 kbit/s
SIGINT received. Exiting... dBm SNR: 10.8 dB, ^CRSRQ: -3.6 dB, NPDCCH detected: 0, NPDSCH-BLER: 0.00% (0 of total 1), NPDSCH-Rate: 0.19 kbit/s
Saving PCAP file
In the decoding, you can see for instance that the PLMN is 901/98 which is indeed assigned to Skylo Technologies.