Directional Antenna
Directional Antenna
(OP)
Hi all,
Looking for a special small size cellular band antenna with very sharp front end radiation pattern. I hope it could be less than 10 degree at half power point. Of course the smaller the better. I have tried Yagi, but it's not narrow enough. The antenna will be used as a receiver only, and we want it to receive the signal in a range of 40 ft away and at most 12 ft wide.
I'm thinking of small size parabolic antenna or special Yagi antenna. I wonder if there is any "magic" to make the antenna small in size and sharp in radiation pattern.
You guys have any idea about this?
Thanks a lot.
Looking for a special small size cellular band antenna with very sharp front end radiation pattern. I hope it could be less than 10 degree at half power point. Of course the smaller the better. I have tried Yagi, but it's not narrow enough. The antenna will be used as a receiver only, and we want it to receive the signal in a range of 40 ft away and at most 12 ft wide.
I'm thinking of small size parabolic antenna or special Yagi antenna. I wonder if there is any "magic" to make the antenna small in size and sharp in radiation pattern.
You guys have any idea about this?
Thanks a lot.





RE: Directional Antenna
Also, what is your purpose? You mentioned range and 40 feet. Is this for testing of some sort?
RE: Directional Antenna
It's a kind of cellphone signal receiver.
RE: Directional Antenna
Yikes.
RE: Directional Antenna
RE: Directional Antenna
RE: Directional Antenna
RE: Directional Antenna
Are you assuming that you require a very narrow beamwidth in order to measure the pattern of your device under test?
RE: Directional Antenna
I think parabolic antenna should have relatively narrow lobe compared to Yagi.
RE: Directional Antenna
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These calculators will allow you to see the relationship between beamwidth, gain, losses, diameter, frequency, etc.
There are many antenna test ranges that seen to get by without such stringent beamwidth requirements on their EMC antenna. You might want to review the situation to see how they do it without, for example, using a 2-m dish to test a cellphone.
RE: Directional Antenna
RE: Directional Antenna
Space antenna elements 0.8 lambda at 2 ghz and you'd get a 10 degree beamwidth at 800 Mhz and 4.25 degree beamwidth at 2 ghz. You could even the beamwidths up by curving the shape of your array if the 4.25 degree beam is too narrow.
It's 75 inches long x very thin if that works. H pole is easiest to make, consider a notch antenna array. Cheap to build too.
kch
RE: Directional Antenna