CoCom regulations and GPS receivers for balloons and cubesats (2016)
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CoCom regulations and GPS receivers for balloons and cubesats (2016)
1–10 of 16 posts
Re: CoCom regulations and GPS receivers for balloons and cubesats (2016)
#2Seems fairly useless to me, for a few dollars I can sample the L1 frequency with a dumb device which has no idea of speed or altitude, and do the calcs with FOSS which is in the wild.
Basically a rule which inconveniences the honest and has zero impact on the bad dudes, whoever they are
Re: CoCom regulations and GPS receivers for balloons and cubesats (2016)
#3Seems fairly useless to me, for a few dollars I can sample the L1 frequency with a dumb device which has no idea of speed or altitude, and do the calcs with FOSS which is in the wild. Basically a rule which inconveniences the honest and has zero impact on the bad dudes, whoever they are
Have you done that?
Re: CoCom regulations and GPS receivers for balloons and cubesats (2016)
#4Seems fairly useless to me, for a few dollars I can sample the L1 frequency with a dumb device which has no idea of speed or altitude, and do the calcs with FOSS which is in the wild. Basically a rule which inconveniences the honest and has zero impact on the bad dudes, whoever they are
Have you done that?
I have. It works.
Used a huge amount of compute though and takes a long time to get a fix.
Re: CoCom regulations and GPS receivers for balloons and cubesats (2016)
#5Re: CoCom regulations and GPS receivers for balloons and cubesats (2016)
#6[2016]
Re: CoCom regulations and GPS receivers for balloons and cubesats (2016)
#7Have fun. https://github.com/gnss-sdr/gnss-sdr
Re: CoCom regulations and GPS receivers for balloons and cubesats (2016)
#8It's important to note that this is in relation to real time position estimation. You can collect the signal measurements and process offline later for telemetry reconstruction.
Re: CoCom regulations and GPS receivers for balloons and cubesats (2016)
#9Earlier quoted context omitted.
I have. It works. Used a huge amount of compute though and takes a long time to get a fix.
Maybe that's why nobody else does
You can use a FPGA, like this 2013 project: http://www.aholme.co.uk/GPS/Main.htm
Or go old school (1991-1992): https://lea.hamradio.si/~s53mv/navsats/theory.html
So yeah, this regulation is absolutely an inconvenient measure.
Re: CoCom regulations and GPS receivers for balloons and cubesats (2016)
#10Earlier quoted context omitted.
Have you done that?
I have. It works. Used a huge amount of compute though and takes a long time to get a fix.
For L1 I think a raspberry pi can have a reasonably fast time to first fix, for offline processing you can go faster than real time. L2/L5 need large sampling rate and a pi is probably not fast enough.. unless if you ditch float32 processing and do 2 bit signal processing, a uni commercialized that: https://radionavlab.ae.utexas.edu/wp-content/uploads/2022/10...