gps returning wrong coordinates

[devil6600]

hi

my gps is returning wrong coordinates, about 30-40kms away from my place. i have tried restarting the gps but still i get the same coordinates. is there any way i can fix this?

thanks

 

[ckshivaram]

the resolution of GPS has gone for a toss........ Keep the GPS ON for an hour or so.. it should recover or else the dsp algorithm is not working properly in the gps....... what antenna are you using... and where is the antenna located.. try to keep it outside the window....

 

[devil6600]

thanks ckshivaram... i am using active antenna. gps and active antenna has a clear sky view (it is at terrace of my house), although i haven't kept it on for 1 hour, i'll try that...

 

[ckshivaram]

can you tell where are you testing it, on hyperterminal or the software for GPS.. Please test it on both and see the difference and update me please............

 

[devil6600]

i have bought few modules and prepared my own board for it. i am using application similar to hyperterminal for receiving gps strings, its Serial Communicator and it can be found in Microcode Studio. you can tell me the software on which you need results i'll test it and send you the results.

 

[ckshivaram]

download the software from the link
https://www.edaboard.com/threads/125778/

i had posted 3 years ago....

 

[ceg]

When your device start to report location NMEA data(GGA data), how much time is your GPS module cold start time?

 

[devil6600]

by cold start u mean time to get valid NMEA strings? earlier i didn't had u.fl connector so i used to connect antenna with alligator clips, so i noticed it took 20 minutes to get a fix, but now using u.fl i get fix within a minute...

---------- Post added at 11:29 ---------- Previous post was at 11:11 ----------

i downloaded the software but on starting it i get "no communication port found" error. i am using usb to rs232, i think the software is not able to recognize usb rs232. i tried changes the port but still i get the same error.

 

[ckshivaram]

Now problem is solved???

 

[devil6600]

yes problem is solved... how do i improve its resolution further? now its showing coordinates 100-200 meters away from my location...

 

[ckshivaram]

thats what you get in low cost gps... you cannot improve it... the cost of gps would be too high if you need accuracy of 100 to 200ft or less... but it is only for military application.. for commercial it is available at high cost.. not for student projects... where gps is available in market for less price....

 

[devil6600]

my gps support DGPS, does DGPS is available in India?

 

[ckshivaram]

Yes they are available in india.. and already used in many applications..