Versions Compared

Old Version 8

changes.mady.by.user Lalanne Laurent

Saved on

compared with

New Version 9

changes.mady.by.user Lalanne Laurent

Saved on

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.

...

Section
Column
width60%

The backfire helix antenna is quite easy to build, cost near nothing and definitively solve this position error problem.

Various helix antennas can be found, i used this one as a guide : http://lea.hamradio.si/~s53mv/navsats/analog.html

Most GPS provides power through the antenna connector, in this case i had to add a 18pF capacitor for DC blocking purposes and avoid a short circuit with the new antenna.

A classic ceramic capacitor can be mounted on top antenna.

I also did the same modification with a M8N module that has a built in magnetometer.

 

Section

Another example using a SMA connector, the DC blocking capacitor is soldered between the antenna pin and SMA connector, close to the GPS module on other pcb side.

 

Column
width40%

Neo6 with helix

 

...

Results

Section

Neo6:

patch

Patch - Helix antenna

On the images bellow you can see two GPS traces, first image is obtained running the helix antenna with +/- 3m error.

The image on the right show the original patch result with more than 20 meters errors/jumps.

If you are really looking for a very high reliability i would recommend to use a NEO-6 GPS module instead of the now popular M8N, this old NEO-6 device is less subject to position glitches. (see next example)

If you want to use a magnetometer you can use a separate HMC5883l module.

 

 

Neo8m: Patch - Helix antenna

...