nRF9160 smallest antenna option

[Pretensor]

Hi all.

I want develop device with  nRF9160. goal - to get smallest size with chip antenna. 

I not so good in RF design, so usually I using recommendation from datasheets. 

I use PCA10090 design as reference, but as I see P822601 that use in devboard very big.

Can anyone recommend a smaller option.  // I mainly focus on US region.

Thanks advance.

Best Regards,

Anatoly

[Jay Tyzzer]

Hi Anatoly,

You can contact the major antenna manufactures.  Linx, Taoglas, etc.  I did see some small ones that Linx had at CES.  You can also check out Digikey and Mouser as they have some drop down options for different type antennas and frequencies. 

[Andreas]

Hi Anatoly,

 

As Jay points out, you need to consult manufacturers and distributors. They should know what alternatives exist and have some numbers to back up which one is how good, etc. We have very little concrete numbers on this yet.

 

In general though, antennas scale with the (qaurter-) wavelength of the frequency they are to support. That is, if you want to support a band with a low frequency, the antenna (and ground plane) will be quite large. nRF9160 support sub-GHz bands, which have a wavelength around three times the wavelength at 2.4GHz, meaning antennas (and ground plane) are approximately three times as large. You might be able to find smaller alternatives, but scaling down an antenna generally degrades the efficiency.

 

Best regards,

Andreas

[rkguy]

I presume that the antenna on the DK was selected because it provided the best reception at a reasonable manufacturing price point. Is that true?

I also wonder if there are alternatives at a higher price point with better gain at similar size

[Andreas]

Hi,

 

The antenna on the DK was selected to give good reception at an as wide number of bands as possible.

 

There are probably smaller antennas out there, but some other performance parameter will have to be sacrificed. First and foremost this would be gain at lower frequency bands, at some point as the antenna becomes smaller also mid and higher frequency bands will also start suffering. This is a trade-off caused by physical laws and indicates the general trend of performance versus size, but obviously one small antenna might be better/worse than other similar sized (small) antennas. Even if better per the datasheet/test board though, it might still not be the best choice in your end-product, you need to choose an antenna that suits your mounting position, enclosure etc. to avoid reducing the performance. You probably also want to do some testing/comparing in your samples between different antennas before deciding.

 

Best regards,

Andreas