Microwave Networking

AliceCooper

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Hello fellow [H] members, as seen in the network pics thread, I recently acquired some Exalt R5005 Microwave bridge. They operate in unlicensed bands (5.8ghz). I have some fun plans for these, but I want to make sure I am not breaking any laws. They can go up to 18 miles. My house is up on a hill and a camping spot I frequent is in line of sight from my back deck about 7 miles away. I was wondering, since these operate in the unlicensed band, should it be ok for me to beam my network connection from one to the other while out camping? I already have everything needed to make this work, just wanting to know if I am breaking any FCC rules or any laws. I am in WA state. I tried googling, but there isn't much info the is easily available.
 

Dawizman

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As long as tire EIRP is within limits, you will be fine.

Chances are though, you may need some decent height on both ends to get line of sight. Those radios won't penetrate trees very well. GPS of both locations would help with running a path analysis.
 

Blue Fox

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While things might be line of sight for you, don't forget about the fresnel zone. Radius is about 40ft at that frequency and distance.
 

AliceCooper

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Trees might be an issue, but I can always climb, it's been a little over a year since I went to the spot, but I'm planning on going there this summer and would be cool to stream some music or something while out camping.

And by EIRP you mean dbm? The specifications sheet says +22dbm at full power in the 5.7-5.8ghz range on a 8/10mhz channel using QPSK.
 

AliceCooper

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While things might be line of sight for you, don't forget about the fresnel zone. Radius is about 40ft at that frequency and distance.

So it would be optimal to have a 40ft buffer around both ends for proper transmission?

Sorry if everything sounds noobish guys lol, I've never done this type of networking before, I got them from my work for free and like to learn new things :).
 

Blue Fox

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So it would be optimal to have a 40ft buffer around both ends for proper transmission?

Sorry if everything sounds noobish guys lol, I've never done this type of networking before, I got them from my work for free and like to learn new things :).
That would actually be in the middle. You'll still need clearance as you get closer to the transmitters, but progressively less to be affected by interference.
 

AliceCooper

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Bumping my old thread as I got my fourth microwave and am ready to put them into action. But before I do I want to make sure I am calculating the EIRP right.

Integrated Antenna (dB Beamwidth) = 23 dBi / 10 degrees
Output Power (Full Power) = +22 dBi
Cable loss = obviously greater than 0, but for the sake of calculating it purely on the antenna I am going with 0.
EIRP = 45 dB

There is another setting called System Gain (dB). But I am thinking that doesn't matter when it comes to EIRP? System gain numbers are 80+ dB. Also I have a tool to help with the fresnel zone and I should be OK.

Note: Just did a path analysis, only have ground interference with the third fresnel zone and point B.
 
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rma

Limp Gawd
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Bumping my old thread as I got my fourth microwave and am ready to put them into action. But before I do I want to make sure I am calculating the EIRP right.

Integrated Antenna (dB Beamwidth) = 23 dBi / 10 degrees
Output Power (Full Power) = +22 dBi
Cable loss = obviously greater than 0, but for the sake of calculating it purely on the antenna I am going with 0.
EIRP = 45 dB

There is another setting called System Gain (dB). But I am thinking that doesn't matter when it comes to EIRP? System gain numbers are 80+ dB. Also I have a tool to help with the fresnel zone and I should be OK.

Note: Just did a path analysis, only have ground interference with the third fresnel zone and point B.

how long is the cable?, a quick subtraction should be -2dB
 

Eickst

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At those lengths you could lose 4 to 20db depending on what coax you used.....
 

Dawizman

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At those lengths you could lose 4 to 20db depending on what coax you used.....
That's cat6 to the radio he's talking about. I believe the antennas are integrated, therefore the loss should be minimal... 1dB or so.
 

Dawizman

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I do believe the maximum EIRP for 5.8ghz in the US is 53dBm. So you should be fine at 45.
 

AliceCooper

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I do believe the maximum EIRP for 5.8ghz in the US is 53dBm. So you should be fine at 45.

Great, these devices are under the old limitation as well which is 53dBm, but I just wanted to make sure how I was figuring out the EIRP looked correct. Thanks!
 
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