Bluetooth Antenna for NRF51822

[test22]

Hello,

I am using the NRF51822 in a low power application and need to transfer the data from the PCB (with the NRF) to the PC over Bluetooth. I need the biggest possible Bluetooth communication range (50-100m?) using a chip antenna. 

All proposed third party modules/smart beacons have a relatively high power consumption for my application. Is it possible to use the NRF51822 in connection with just a matched chip antenna to transfer the data over Bluetooth? If yes, which antennas and matching circuits are suitable?

Thanks,

BR

[Andreas]

Hi,

 

50-100m range using a chip antenna is ambitious, but might be doable depending on your environment. To have a realistic chance you need to do your layout and antenna design well, replicate the nRF51 reference layout or use a matched balun (Johanson 2450BM14E0003 or ST BALF-NRF01E3) and add a pi network for matching the chip antenna. For optimal performance you should choose a chip antenna that is designed for mounting where you intend to mount it on your PCB, either in a corner, along a long rectangle edge or along a short rectangle edge. If your PCB is large enough to accomodate a monopole this is recommended. Without knowing your design we can not recommend a part. The matching circuit will depend on whatever antenna you use and the impedance it has in your design, a pi network will let you match for pretty much any combination though.

 

Keep in mind though that making your own PCB is not going to reduce the power consumption compared to a module with only a nRF51822 on it. If the current consumption is too high you might want to look into the nRF52 series instead, which will give you both lower power consumption and longer range.

 

Best regards,

Andreas

[test22]

Thank you very much for the support. It helped me a lot.

My PCB is large enough for a monopole antenna. My design would consist just of the NRF51822, the matching network and the monopole antenna. I would transfer sensor data (connected over I2C bus) over Bluetooth. Can you possibly just give me a hint, which monopole antenna I could use or at least which manufacturers I can base my search on? I cannot find any suitable part. 

Thanks,

BR

[Andreas]

Hi,

 

You can make your own printed antenna (in your PCB). See this white paper.

 

Best regards,

Andreas