Undergrad Question about microwave reflections

[kelly0303]

Hello! I have an experimental setup in which I need to send microwaves (MW). I would like to reduce the unwanted scattering of the MW as much as possible and I was wondering what materials are best for this (in vacuum). For example, if I make some holders of metal (e.g. aluminum or steel) I assume they will affect the MW trajectory. If I make them of ceramics for example would that help i.e. do microwave interact with ceramics?

 

[Baluncore]

To microwaves, aluminium will be like a mirror, while the edges, or wires, will diffract the beam.

Solid insulators, like glass, plastic or ceramic, will behave like a lens, so will refract the beam.

The most transparent will be thin glass fibres, or a low density ceramic foam.

 

[berkeman]

I have an experimental setup in which I need to send microwaves (MW). I would like to reduce the unwanted scattering of the MW as much as possible and I was wondering what materials are best for this (in vacuum).

Can you give any more details of the experiment? What band of microwaves and at what Tx level? Are you sure you will be compliant with EMI regulations outside of your lab?

More details would help, but have you looked at EM absorbent cone material to absorb any stray reflections? The material is commonly used in RF anechoic chambers and in places where you want to absorb EM:

https://theemcshop.com/anechoic-cha...-expandable-polypropylene-microwave-absorber/

 

[tech99]

I think wood might be useful as it is slightly lossy to microwaves.