pocket_trk with raw option?

[CESBIOTEAM]

hello
you have done a wonderful work. congratulation
I have one question for you:
I have a receiver with 2 channels. My wish is to record only one channel (the first one). and best would be to track and to record at the same time... BUt I do not undertand how I can do that.

when I use this file to configurate pocket_L1L2_4MHz.conf and when I run
pocket_dump -c pocket_L1L2_4MHz.conf -t 1 ch1.bin
I have a file with 8Mo per seconds, seems to be logic. (2 bits * 2 (I&Q) * 4MHz *0.5 = 8Mo/s
Now if I use this command pocket_trk.exe -c pocket_L1L2_4MHz.conf -raw STEAM.out
I have a IF file for one second with a size about 4Mo.. why? I assume that it is not possible to record only the first channel. I thought my file would be 16Mo for one second ...

is it a normal behaviour?

thanks again

[tomojitakasu]

The option -raw of pocket_trk outputs IF data in RAW8, RAW16 or RAW32 format, not in INT8 or INT8X2. Refer p.31 of the following slides.

https://gpspp.sakura.ne.jp/paper2005/pocketsdr_seminar_202411_revA.pdf

[CESBIOTEAM]

Ok it is clear for me !
And just one point. Is there a way to dump or calculate for a specific duration for pocket_trk ?with pocket_dump i notice the -t option but it seems not to be implemented with pocket_trk

And an other point , is there a way to process tracking with L1 gps on the second Channel (rf2) not for the first one (rf1)? I know with your schematic it Can not work but i change your design to record L1 signal on the second channel also...

[tomojitakasu]

(1) Use -toff option to start at a specific time. Push Ctr-C to stop tracking.
(2) In FE 2CH, CH1 and CH2 are dedicated to L1 and L2/L5/L6 bands, respectively. In FE 4CH, all CHs can be configured for either L1 or L2/L5/L6 bands.

[CESBIOTEAM]

Ok I understand.
And last point concerning the LOG file written by pocket_try. I assume it is possible to plot this file with pocket_plot.py
anyway I have some problems if for example I write the following command:

And last point , if I want to plot SNR versus elevation angle (as your document in the last sheet) , I need to have NAV data. but where are the NAV data. I assume now NAV data are included in LOG file but I am not completely sure

if you can clarify this point, it would be very nice!? thanks so much

[tomojitakasu]

pocket_plot.py has not been maintained.
It will be removed in the next release.

[CESBIOTEAM]

Ok yes I saw that the last update was two years ago...And... is there a possibility to use the LOG file ,for exemple C/NO for a particular PRN versus élévation or Time for exemple ?maybe we may Do that with nmea file recorded but I do not know if a particular library (python or maltab) has already been written to do that...