Plastic enclosure over reference design

[Victor Nascimento]

How does a Plastic enclosure affects the performance of my RF antenna?

I'm designing the PCB + housing and as it have to be small, i'd rather use a BALUN + Chip antenna to save space. As I am a undergrad student, anyone with more experience can help me on this?

Thanks in advance

[Victor Nascimento]

But in this case, my matching circuit is done by the BALUN, right? Do some extruded cuts near the antenna make any difference (like holes)?