SparkFun Forums

[Andrew02E]

Who found that new chip-scale GPS antenna?! I just got done designing a project around Antenova's GPS antenna (http://www.antenova.com/?id=524) and the GR-10 module.

I haven't received the boards yet, but I've never used the GR-10 before and was wondering how well it performs. Who here has used it before, and how did it do?

[dwrenne]

Has anyone any idea how you would wire this in to a GPS rec. unit

Cheers

Diarmuid

[cytos]

Who found that new chip-scale GPS antenna?! I just got done designing a project around Antenova's GPS antenna (http://www.antenova.com/?id=524) and the GR-10 module.

Can I ask how you got on with this? I've been looking at trying to replace a ceramic antenna with the Antenova module and (being a novice) got all worried about vias and RF fencing. Any advice for using the Antenova would be great...

[ohararp]

Checkout www.ohararp.com/blog to see my latest use of the antenova antenna.

Implementing it was pretty simple. Just make sure you have a 50 ohm trace with a 100 pf capacitor in series in the trace tied to directly to the rf input of the gps.

[Andrew02E]

Cytos,

Digikey and Mouser both stock the Antenova antenna. I believe there is information on it readily available on Antenova's website. If not, just e-mail them for more information.

[ohararp]

Andrew,

I found the Antenova was able to get a signal but could not lock on more that 4-6 satellites. I think I will be putting an additional lna on this design. Have you had any better luck?

Ryan

[Andrew02E]

Unfortunately the project is sorta at a stand-still. My design does include a LNA though (RF Micro Devices RF2373), so when progress is made I will post the results.

[cytos]

I'd already got some of the antenova here in the UK, but I've decided to press on using the new tiny ones from SparkFun that just arrived. I'll let you know how I get on.

In case anyones interested there's another small antenna available from Fractus that seems to have similar abilities:

http://www.fractus.com/main/fractus/srw_1.575/

[ohararp]

I think that with all these antennas an lna is going to be a must.

[cytos]

I've been using the Antenova and fixing 4-6 satellites as Ohararp mentioned - did anyone have any better results with a LNA?

[scalegps]

With these new little planar/inverted F linear polarized antennas an LNA is basically a must. You will get some operation in ideal (open sky) conditions, but under foliage and other obstructions you will lose lock almost immediately.

In addition, due to the linear polarization the sensitivity pattern is usually less than ideal. One other issue that might come up is multipath. In a multipath environment your position stability will suffer as compared to a normal circularly polarized ceramic patch or helix antenna.

In the applications that these antennas are designed for (cell phone/PDA) the linear polarization is actually a good thing as it allows the antenna to pull in reflected signals, such as when you are in a building. The position accuracy may not be great, but it's better than no fix at all.