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Taoglas FXP-14 U.FL antennas

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Horsa:
GPS signal reception has to be dealt with extreme care. Not to tell about indoor GPS reception.
As per my reply to your very first inquiry to your topic, the first think to consider when choosing a GPS antenna is whether the GPS receiver needs an active antenna or not. FXP-14 is obviously not.

* manual > GPS antenna specifications > active or passive?
* manual > GPS antenna specifications > if gain > 1 or dBic > 0 (typically > 10), then you need an active antenna
* manual > is a GPS input amplifier documented? then you probably need a passive antennaIf no info is given, everything is possible: try and measure with patience.

Plantje:
The only thing I can find on the antenna subject in the documentation is on page 17 of the documentation under this link: http://www.maxon.com.au/udocuments/EM770W_HW_SPECV1.12.pdf

There it does state: "It is recommended that the antenna whose gain value is greater than 1dBi be used."
So, this means I should have ordered an active antenna?

How is it possible that 3G does work?

To be honest: I am not a radio specialist. I am able to open my device, insert a mini pci-e card and connect antennas. But it is really frustrating to see that nobody can just sell me a mini pci-e card that supports 3G and GPS and works with the antennas that come with the card!

Horsa:

--- Quote from: Plantje on January 13, 2011, 12:29:19 PM ---So, this means I should have ordered an active antenna?

--- End quote ---
This means, you should have ordered an antenna with at least active GPS part. Documentation tells something like this:
- main antenna connector: U.FL antenna with passive cellular part + active GPS part
- aux antenna connector: ideally the same
I do not know of any of such antennas.

Alternatively, you could try like this:
- main antenna connector: passive cellular antenna (U.FL)
- aux antenna connector: active GPS antenna (U.FL)
and hope the diversity engine does a good job. Still, I do not know of any of such GPS antennas, but there could be some.


--- Quote from: Plantje on January 13, 2011, 12:29:19 PM ---How is it possible that 3G does work?

--- End quote ---
Because of the passive cellular part of FXP-14.


--- Quote from: Plantje on January 13, 2011, 12:29:19 PM ---... But it is really frustrating to see that nobody can just sell me a mini pci-e card that supports 3G and GPS and works with the antennas that come with the card!

--- End quote ---
You are not the first we are supporting with the same or worse problem...

PS: try to contact Maxon ...

Plantje:
Have you ever heard of these antennas?
http://www.taoglas.com/antennas/GPS_Antennas/Internal_GPS_-_SMT_Loop_Antennas/

Perhaps that will work.

Yes, I think I should try to contact Maxon.

Horsa:

--- Quote from: Plantje on January 13, 2011, 08:40:33 PM ---Have you ever heard of these antennas?
http://www.taoglas.com/antennas/GPS_Antennas/Internal_GPS_-_SMT_Loop_Antennas/
Perhaps that will work.

--- End quote ---
I have seen them before. But it is NOT a step forward toward your solution. Short GPS specifications are very similar. For example, the GPS Gain:

* FXP14: 2.2 dBi
* GLA.01: 2.5 dBiBut the GLA series needs a support PCB whit at least the following requirements:

* much more complex design (e.g. impedance-matched lines)
* much bigger ground-planethan FXP. By the way, I am really not sure that a gain of dBi > 1 (UMTS module documentation) is enough. Active antennas start with an overall gain (antenna intrinsic gain + amplifier gain - cable loss) of at least 10 dBi.

Do not forget that most active antenna are DC supplied through the same receiver connector. Probably it is nowhere documented that your UMTS module support that. So, you should start assuming that it is not supported.

Should you get qualified support from other sources, please do not forget to share back here.

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