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[Cree415]

Hi, I'm a student working on a project that involving RF interference. I'm working with facility that can only open up 10 channels at a time, and there are more than 30 stations. Each station can open up a channel if its clear, if it sees that no other station is using that channel. Each station contain antennas that are omnidirectional. The facility would like to use more than 10 channels, originally I thought this could be done using a faraday cage, however, they don't want to create a faraday cage for each station. Then I came across the idea of an antenna array. Lets say for simplicity sake, there are 20 stations, there are 10 stations on the left and 10 on the right, and the antenna array in the center. Can I use the antenna array to "block the signal coming from the right" like as if i'm creating a null from 90 to 270 degrees?

[bigSteve]

Generally you can't use arrays to create nulls across entire angular ranges, such as half the sphere.

You can use them to minimize radiation in particular directions, but the isolation will only be on the order of 30 dB (I would guess) for 10 elements.

Possibly you could try TDMA, CDMA or FDMA to multiplex your system?

[Cree415]