planar inverted f antenna

Hi,

With a PIFA, you can either use a planar inverted F structure (the 3-dimensional structure), or you can implement using PCB traces. Are there pro's and con's to both structures? Or do they both have similar performance?

To me it seems like the PCB trace would be the ideal solution. It's just a PCB trace, so it essentially costs nothing. The planar version seems more complex. Does the planar version offer better performance (better radiation patterns, more efficiency, etc.)?

Thanks.

Actually the names are different. One is PIFA (Planar Inverted F Antenna), and the other is IFA.
Compare to IFA, PIFA has less radiation through the direction of the ground plane (which is an advantage in mobile phones, reducing SAR), and also has slightly higher gain in both vertical and horizontal polarization (another advantage for mobile phones).

Thanks for the response. For me, I like the simplicity of a PCB trace. I'd also like to have as omni-directional of a pattern as possible. Are there any big negatives with using an IFA?

Also, how far does an IFA need to be from other components on a PCB? (my concerns being the components distorting the antenna performance, and also the antenna inducing noise on the components)

For IFA if the ground length provided below the active element is approximately λ/4, the omni-directionality of the antenna is fine for most of the applications.

If the ground-plane is longer than λ/4 the pattern become multi-lobed, and if the ground is much smaller than λ/4 the tuning become critical.

To don’t affect the IFA performances the components shall be placed at a distance from the active element, greater than the distance between active element and ground.

I was planning on putting the IFA on my main PCB, which would have a wavelength much greater than λ/4. According to this statement, this would give me a multi-lobed pattern, which I would not want. Are there any ways I can avoide this? Can I somehow isolate the antenna ground plane from my main ground plane (split the planes)?

To make smaller ground plane always is easier than make greater.
Do some cuttings, but simulate or measure in the same time the antenna pattern.