osqzss / gps-sdr-sim

Software-Defined GPS Signal Simulator
MIT License
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Can't get a stable 3D fix with Adalm-Pluto #364

Open Papabearer opened 1 year ago

Papabearer commented 1 year ago

Hello everybody,

At the moment I am having an issue regarding getting a stable 3D gps fix from my ADALM-Pluto and would appreciate some recommendations on how to get a more consistent fix. Just as a heads up, I'm using the linux terminal with Debian.

This is what I compiled:

./gps-sdr-sim -e brdc0060.23n -l 30.286502,120.032669,100

What I use to run it:

player/plutoplayer -t gpssim.bin

So far I have tried adjusting the bandwidth and attenuation to no avail. These are some images I captured regarding what my gps-receiver finds when I run the script.

image

So my question is, is there anything else I can try to maintain a stable 3D fix? Help would be greatly appreciated 😄

osqzss commented 1 year ago

Try a good exernal clock. The frequency offset of the onboard XO could be too big.

vxling commented 1 year ago

i cant get a stable 3d fixed too, for pluto SDR i replaced the crystal with a 0.5ppm model: DSB321SDN 40M 40.000MHZ 3225 TCXO XTW40000PBA, I don’t know why.

Receiver is U-Blox M8030 72ch.

i also tested with hackrf One with an external clock, no 3d fixed too.

vxling commented 1 year ago

I got 3d fix with ublox now, but the iphone can’t locate

yosefzh commented 4 months ago

I got 3d fix with ublox now, but the iphone can’t locate

i have the same issue i managed to spoof my android phone but couldn't spoof my iphone, do you have any idea why ?