I was reviewing my old GPS Jamming slides and it terns out jamming can accrue
with a received jammer signal strength of -90dB. it is possible the 1575.02MHz
signal is still to strong and we are self jamming. is there a way we can change
the 25MHz clock to 12.5MHz to test this possibility?
I also recall that it was standard practice for GPS to implement an adaptive
notch filter in order to cancel out stray CW interference.
the transfer function for an analog notch filter is
where w= 2*pi*Frequency
and b is the bandwidth of the notch
while this may be the most functional option Kenny notified me it is
computationally expensive. I also don’t know if this is how it is actually
implemented in GPS receivers. that information shouldn't be hard to find but iv
been banned from working on PSAS stuff tell I’m done with capstone.
if it proves to be to costly in software than there is a hardware solution but
has special constraints and may not be enough. we can attach a shielded peace
of wire (probably coax) that is a quarter wavelength of the 1575.02MHz signal.
this would act as a very narrow notch filter.
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