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Bearing from GPS

S

SeniorSe

Lurker
I'm looking for an app which allows me to log gps data including position, speed and bearing. The last two should be calculated using doppler shifts, independent from the position measurements. I have tried Androsensor which according to the specification should be able to log bearing (in all versions after 1.9.4.4) but I cannot find where this is logged or shown.

Thank you.
 
GPS doesn't work off of doppler shift. GPS uses triangulation to locate a postiion and just a position. Doppler shift is the change in measured/perceived frequency due to relative velocities (the passing car's horn's pitch rises as it nears and drops as it goes away.). Instantaneous velocity (speed and direction) can only be estimated with GPS by a change in distance divided by a change in time function (perhaps employing Kalman Filtering).
 
GrouchoM is right. And even if your cell phone had a Doppler radar gun built into it, I don't see how Doppler could reasonably be used to determine bearing.

But most smartphones have built-in compasses which can determine bearing (if the phone is affixed to a vehicle), and GPS, which can be used to calculate position, speed, and perhaps bearing (though I've never seen it used to calculate bearing).
 
SeniorSe isn't completely off. There used to be a navigation system that worked on land and "near shore" called LORAN. It actually did use the doppler shift to determine your position and to determine speed and bearing. LORAN was a series of ground based towers. Each tower emitted a signal at a certain frequency and a carrier code. Your receiver would read the carrier code and analyze the received frequency and, based on the received actual frequency (which does vary slightly over distance), determined your position. It required at least three towers to be within range to "do its thing."

So, in general, LORAN was based on frequency shift and straight lines and GPS is based on signal degradation and concentric circles.
 
Is the LORAN for Android? SUre, doppler can be used for position & velocity (think Radar) but the OP was asking about an Android app.
 
No, LORAN is from an antiquated system used years ago. Android was still a twinkle in someone's eye during the LORAN system days.
 
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