Feed Line

[Zsolesz]

Hi,
Please have a look and let me know about it.

This board is two layers and i used chip antenna. I would like to ask you, Is this design is correct? How can i plan with less antenna area?
I try YJ-18010-nrf52840 module and worked very well. I could communicate between two boards at 150 meters. I dont understand YJ-18010-nrf52840 module design, I saw an short feed line. Can you explain how it work?

YJ-18010-nrf52840 module link : http://www.holyiot.com/eacp_view.asp?id=278

Thanks for the reply in advance.

[Andreas]

Hi,

 

You are short one component in the RF matching network. You need to add C4

You should also replicate the reference RF matching network PCB layout:

 

Except for that you can move the other components around as you wish (within reason) to minimize the size of the design. The feed can be made much more straight, just re-organize the components a bit. If you are not able to fit a wide trace in this area it is not critical if it is not 50 ohms. E.g.

 

Best regards,

Andreas

[Zsolesz]

Hi,
Thank for answer!
I made version 2.0 PCB, Can you check this too?

I used (JOHANSON TECHNOLOGY 2450AT43B100E) chip antenna.
2450AT43B100 Datasheet

[Andreas]

Hi,

 

This antenna is 'corner mount' (see the datasheet), while you have mounted it as 'end mount' (see this guide by Johanson). It will probably still work, just not optimally, varying between different models. It probably causes the antenna to detune quite a bit though, you should add another component to the antenna matching network to make sure you can match any antenna impedance. Either a parallel component between L3 and the antenna, or a series component between L4 and C28.

 

Best regards,

Andreas

[Zsolesz]

Hi,

Thank you for the all answer helped a lot!
I am looking for 'end mount' chip antenna and change it.

Best wishes!