90 degrees rotated MIFA 2.4GHz Antenna reference design?
There needs to be a ground plane and some distance between the antenna and that ground plane. If you change anything in that respect, you've changed the design.
That doesn't mean that the antenna will stop working, it will work but it might be less efficient (less power is transmitted / received) and more power reflects back into the amplifier driving the antenna. So performance is expected to degrade.
If you're fine with that then you can still do &quot;whatever&quot; you like. Some cheap RF modules from China have antenna designs that look like little thought/design has gone into them. But these still work just don't expect the maximum performance (range) from them.
So in the end it is your choice, stick exactly to the NXP design and you know what you will get. Or change it to your needs and your results may vary.
Have you considered using a &quot;chip antenna&quot;, these might give you more flexibility regarding the ground plane.