antenna in 20mm circle PCB

RE: antenna in 20mm circle PCB

KnightYusuf — Sun, 23 Oct 2016 07:52:08 GMT

What effect has the DCDC on the antenna ?

RE: antenna in 20mm circle PCB

Jose Xavier — Tue, 10 Mar 2015 13:57:32 GMT

What do you suggest to not use the DCDC internal regulator?

RE: antenna in 20mm circle PCB

Jose Xavier — Tue, 10 Mar 2015 13:56:12 GMT

Can you point on the image what "huge slot" on the ground plane you're saying is bad for the antenna? thank you

RE: antenna in 20mm circle PCB

Håkon Alseth — Tue, 01 Jul 2014 12:45:23 GMT

There are two things that I can pin-point to regarding the range, other than what other users have suggested. The first thing is that you're lacking an antenna tuner network (PI-network). This is essential for every antenna, as every design has different characteristics in terms of stray capacitance, component placement, ground plane, layers, PCB size and shape, and the casing usually has effect on the antenna impedance.

Each design is unique in terms of the antenna impedance. If you have a perfect 50 ohm antenna for one design, and copy it into a completely different design, you're not guaranteed the same performance.

There are a couple of threads on this:

devzone.nordicsemi.com/.../ devzone.nordicsemi.com/.../

The second thing, if you're testing with the internal DCDC enabled (we do not recommend using it), you may see reduced range due to the DCDC's stabilizing time causing ripple on certain regulators internally, thus raising your noise level in RX (and you'll get a dirty TX modulation).

RE: antenna in 20mm circle PCB

Janek Mann — Tue, 01 Jul 2014 10:03:26 GMT

I have used variants of the meandered inverted-F antenna from this TI app note: www.ti.com/.../swra161b.pdf for several years with good success in space-constrained applications.

RE: antenna in 20mm circle PCB

Nikita — Tue, 01 Jul 2014 09:45:35 GMT

I would suggest inverted-F antenna. colinkarpfinger.com/.../

RE: antenna in 20mm circle PCB

nan — Tue, 01 Jul 2014 09:16:40 GMT

Which kind of PCB antenna is better? any suggestion?

RE: antenna in 20mm circle PCB

nan — Tue, 01 Jul 2014 09:12:26 GMT

The right PCB Layout:

Which kind of PCB antenna is better? any suggestion?

RE: antenna in 20mm circle PCB

nan — Tue, 01 Jul 2014 09:09:33 GMT

I get it. So sorry for the bad layout.

RE: antenna in 20mm circle PCB

nan — Tue, 01 Jul 2014 09:06:10 GMT

Thinks a lot. I;ll make more space for the antenna, and good ground plane. The Molex "on-ground" one is 4mm high, so, it can't be used. Thinks a lot for the advices.

RE: antenna in 20mm circle PCB

Mihail — Tue, 01 Jul 2014 06:41:23 GMT

I see now it is the BAL for nRF51422, but in general bad soldering of the BAL is a common cause for such range problems.

RE: antenna in 20mm circle PCB

Nikita — Tue, 01 Jul 2014 06:29:53 GMT

That's BAL-NRF02D3 for WLCSP package.

RE: antenna in 20mm circle PCB

Mihail — Mon, 30 Jun 2014 20:52:52 GMT

I see you are using the BAL-NRF01D3. Bad soldering on it can cause the problem. Please check it with a microscope to see if all 5 pins are ok. Beside on the picture pads for it, does not seem right. Please check this document for the right layout.

RE: antenna in 20mm circle PCB

Janek Mann — Mon, 30 Jun 2014 15:39:47 GMT

You would struggle to fit a well-performing PCB antenna in the same space as that chip antenna. Though, as you experienced, a small chip antenna doesn't perform great either. Your best option is certainly to make more space for the antenna (at least in my experience). Your ground plane is not fantastic though (there's a huge slot created by the power trace, I would try to break up that power trace to get a better ground plane). For a really small antenna, the Molex "on-ground" one is excellent: www.molex.com/.../479480001_sd.pdf