Hi Sylvain,
Thanks again for your suggestions.
I have performed some captures with some offsets w.r.t. to channel frequency. Then I ran the gmr1_rx binary on the recording. In your presentation video during CCCH, you mentioned that sps should be set to 4. The Wireshark output is shown below.
GSM TAP Header, ARFCN: 0 (Downlink), TS: 0, Channel: CCCH (0)
Version: 2
Header Length: 16 bytes
Payload Type: GMR-1 air interfeace (MES-MS<->GTS) (10)
Time Slot: 0
..00 0000 0000 0000 = ARFCN: 0
.0.. .... .... .... = Uplink: 0
Signal Level (dBm): 0
Signal/Noise Ratio (dB): 0
GSM Frame Number: 30
Channel Type: CCCH (2)
Antenna Number: 0
Sub-Slot: 0
Perhaps the reception of the Thuraya signal is rather bad on my side. When I used the osmocom_fft to check the broadcast channel, I could not identify it. Switching to a homemade LHCP antenna didn't seem to help either.
I might try different locations next time. Currently I used a compass to roughly align my antenna direction towards the satellite (at 44deg E).
What do you think? Thank you in advance.
Best regards,
Johann