External GPS antenna for nRF9160dk

[saiff]

Hi, i've been trying to use gnss function indoors and therefore i need to install an external antenna on my nrf9160dk.

I've read the requirements but i'd like some professional help choosing between two antennas that i believe can be used for my case.

here's the datasheet of the antennas i chose :

 Echo_2_Rev_1_6_1-2930478.pdf (mouser.fr) 

2861064.pdf (farnell.com)

thanks in advance,

kind regards,

[Jared]

Hi,

In general we don't give recommendations on third party products that we don't use or haven't tested ourselves. Thus, this question should be directed to your distributor or manufacturer of the antennas that you are considering. One note regarding the two antennas, is that only one of them has an internal LNA, which is something that we strongly recommend. This means that if you choose to go with the one that doesn't have one, then you have to add one externally.

regards

Jared 

[saiff]

Hi Jared, thanks for your response,

can you give me a reference of an antenna that you have tested and know that it can do the trick?

thanks in advance,

kind regards,

[Jared]

Hi,

Not sure if that has the correct connector. In any case you should really direct this question to your distributor. They will be able to help you find the correct antenna from their supply.

regards

Jared 

[saiff]

Hi,

my supplier informed me that the SWF RF connector isn't intended to be used to hook up an external antenna, is there another way to improve the GNSS module results in order to get a fix indoors?

Thanks in advance,

regards,

[Jared]

Hi,

On that specific antenna that you asked about or in general? The SWF connector on our DK is specifically made to enable external antennas to be connected to the DK.

In general getting a fix indoors is hard, and there is really few improvements that you could implement except for using a bigger and better antenna.

regards

Jared 

[saiff]

Hi,

here's the response i got from my supplier "The SWF RF connector isn’t intended to be used to hook up an external antenna, it’s there to hook up a test probe adapter to measure power during operation." 

and this got me really confused, i'd really appreciate it if you can help me finding an external antenna that i can use.

regards,

[Jared]

Hi,

Not sure what the supplier was referring to but: 

From nRF9160 DK Antenna interfaces documentation:

The nRF9160 DK has three antenna interfaces for Long-Term Evolution (LTE), Global Navigation Satellite System (GNSS), and the 2.4 GHz radio.

The LTE and 2.4 GHz RF signals are propagated through two coaxial connectors with switches that can be used to disconnect the corresponding antenna from the radio if adapter cables are connected. This makes it possible to perform conducted measurements or to attach external antennas to the radio.

The GNSS signal is RX only. A Low-Noise Amplifier (LNA) with integrated filters amplifies and filters the signal before it is fed to the GNSS RF port on the nRF9160 DK. An external active GNSS antenna can be connected to J2. When using an external antenna, the LNA should be disabled.

The DK has the following antenna interface connectors:

• J1 – Connector with a switch for the LTE antenna (A1)
• J2 – Connector for an external GNSS antenna
• J3 – Connector with a switch for the 2.4 GHz antenna (A3)

For more information on the GNSS antenna interface, see GNSS.

 

[saiff]

hi,

the GNSS documentation you just send states "An external active GNSS antenna can be connected to the U.FL connector J2. 3.3 V DC is fed through J2 to supply the LNA of the external antenna."

but at the begining of this conversation you told me that i can't use the antennas i suggested because they had a u.fl connector

Jared said:

Well, we do not use any external antennas in our products. The two antennas that you have posted has u.FL connectors while we use SWF connector on our development kits. If you can find something like the one that has a internal LNA with SWF connector then it's probably ok,

did i understand something wrong ?

[saiff]

i found this recommendation from your colleague to another developer 4 years ago in the thread , i don't if this is still valid or not

antenna documentation : 206640-0001 Molex | Mouser France

 

[Jared]

Oh my days,

You're actually totally right on this. I just noted that the connector on the nRF9160 is actually indeed a u.fl, all of our other connector on our devkit including connector for nRF9160 LTE is SWF, which is why I assumed that the one for the GPS also was that. 

I'm so sorry for the confusion, 

saiff said:

antenna documentation : 206640-0001 Molex | Mouser France

That antenna looks ok to use. 

regards

Jared 

[saiff]

hahaha no problem glad that i found the one.

thank you for your time,

regards,