How do signal Boosters effect Antenna Gain and Beamwidth?

[scottjsee]

Hello..

I am currious of the effect of injected Amplification, and how a product like the LUXUL Shockwave 1 Watt amplifier would effect the Antenna Gain and Beamwidth.

http://www.wirelessnetworkproducts.com/download/hd25036_specs.pdf

It's my understanding Antenna dBi and Beamwidth are mutually exclusive. When dBi goes up Beamwidth goes down, and vice-versa. With a product like the LUXUL would the beamwidth shrink? Or, am I thinking about this wrong?

[Scott Fella]

Scott... Booster can put you pass the regulation and can get you in trouble. I don't think the pattern changes much but an amplifier does what it does. Amplifies both your signal and noise. I have used boosters in the past just to test it out. It's was for point to point links not client access.

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[George Stefanick]

Boosters have a place, like Scoot mentioned on PtP links. It could impact your antennas coverage a bit. But note like Scott mentioned it also boost your noise floor. I would never put this on an ap with client devices. As for antenna gain, you would calulate the radio power + boost + antenna gain - cable and connector loss

If you have a 100 mW (20 dBm) radio power and add 3 dBm boost (23 dBm) you would have 200mW. If you add 3 dBi antenna gain you would have an EIRP of (26 dBm).

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"Satisfaction does not come from knowing the solution, it comes from knowing why." - Rosalind Franklin
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‎"I'm in a serious relationship with my Wi-Fi. You could say we have a connection."

[Scott Fella]

Who is Scoot??? Haha

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[George Stefanick]

LOL thats your new nick name!

__________________________________________________________________________________________
"Satisfaction does not come from knowing the solution, it comes from knowing why." - Rosalind Franklin
__________________________________________________________________________________________
‎"I'm in a serious relationship with my Wi-Fi. You could say we have a connection."

[scottjsee]

Thank you gentlemen.

I am looking for a more scientific answer on dBi to beamwidth relationship..

I don't fully understand the calculated radio power example you posted George, but I'll look into the significance with an open perspective. This is question is mostly academic, I was discussing the relationship between antenna dBi and beamwidth to a co-working (as one goes up the other goes down) and we started talking about the significance 1000mM amps from LUXUL would alter these relationships.

Can either one of you recommend a good article explaining regulatory 802.11 math. I would like to satisfy my curiosity by calculating the effect of these devices.

[George Stefanick]

I can also recommed the CWNA study guide from CWNP.com ..

__________________________________________________________________________________________
"Satisfaction does not come from knowing the solution, it comes from knowing why." - Rosalind Franklin
__________________________________________________________________________________________
‎"I'm in a serious relationship with my Wi-Fi. You could say we have a connection."

[vlad.mihailov]

Scott,

The antenna gain will not be affected by the amplification of the signal (or so is in theory). Even antenna patterns are not related to mW in any way shape or form. Antenna pattern diagram shows you the main axe where the power is strongest and then shows how it drops as you move around the antenna. Say you have a gain of 10 dBi in the main direction - that simple means your signal (irrelevant to its power) will get an increase of 10 dB over the units you measure it in. As you move around that gain gets smaller and at some point will loose 3 dB - that will be your "main lobe" or beamwidth. Again irrelevant of the actual transmit power. Amplifiers are doing exactly that - they amplify the signal as it leaves the transmitter. That signal be bigger than the signal that leaves the radio or smaller - it will not affect the actual gain of the antenna.

I am not sure if this answers your question. Please provide your feedback.

Thank you.

[Scott Fella]

Here is a description of what you are looking

http://www.teletopix.org/4g-lte/beamwidth-and-relation-between-beamwidth-and-gain/

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