antenna on flex pcb

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Anonymous
Not applicable

My application requires to use a flexible thin pcb.

I would like to use the antenna design form the cypress antenna reference guide (http://www.cypress.com/documentation/application-notes/an91445-antenna-design-and-rf-layout-guidelin... ), but in this document they only refers to pcb boards with thickness of 0,508mm (20mils). The flex pcb is only 0.1mm (4mils) thick. How I have to adjust the width of with of the transmission line?

And is it possible to have the antenna and ground plane at the same layer on a one layer pcb (would be a lot easer for prototyping)?

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1 Solution
Anonymous
Not applicable

I don't know how much you need to adjust the antenna width to compensate for the decrease in depth, but you can either do some wireless transmissions antenna calculations to determine that, or some trial and error?

You could have the ground plane on the same layer as the antenna, but the purpose of the ground plane is to provide the back wall of a monopole antenna. Moving the ground layer to the same layer prevents you placing it for a monopole arrangement, and prevents the noise reduction benefits of the ground plane wall behind the antenna. It does allow for a more omnidirectional antenna however.

Ultimately, I think you would need to test the layout you go with to find the best option, or to do some wireless design analysis at a more mathematical level to determine the affective results.

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1 Reply
Anonymous
Not applicable

I don't know how much you need to adjust the antenna width to compensate for the decrease in depth, but you can either do some wireless transmissions antenna calculations to determine that, or some trial and error?

You could have the ground plane on the same layer as the antenna, but the purpose of the ground plane is to provide the back wall of a monopole antenna. Moving the ground layer to the same layer prevents you placing it for a monopole arrangement, and prevents the noise reduction benefits of the ground plane wall behind the antenna. It does allow for a more omnidirectional antenna however.

Ultimately, I think you would need to test the layout you go with to find the best option, or to do some wireless design analysis at a more mathematical level to determine the affective results.