# 5700BH20 Link - Please Advise

I am working on a 18.06mile link, this was the distance Slave gave when it was able to register once, very low RSSI.

It is w/ 27RD reflector. Do you think 18-20mile link is just fine for this? Does the elevation attribute to poor signal as Point A is too high from Point B.

To give more scenario:

Point A = 300Ft Above Sea Level
Point B = 2400Ft Above Sea Level
Distance = 18.06miles.

Can you elaborate more?

This link should have -70dB at each end which should give you enough for a 1X link but probably not a 2X link.

What is the noise floor at the master and slave? (you will have to switch the master to a slave to do a spectrum analysis). If it’s close to -70 you may not get a link at all.

18 miles is a pretty long shot, you will have to spend quite a bit of time peaking the two dishes.

Are there any Fresnel issues? the Fresnel zone is 66’ at 9.5 miles.

What do you suggest if I make it a 2 hops/pair link, supposed, I will divide this 18.06 to make:

When you say 1X, means 10mb, right? and 2x is 20mb?

Link A: 8miles
Link B: 10miles

Can I be able to make 2x on it?

wht about earth curvature?

I cannot say without more information.

Are there other 5.7 BH’s and/or AP’s - canopy or otherwise?
What is the noise floor at each point in the path?
How much bandwidth are you trying to transport?

There are lot of APs 5735/5775/5815/5835.

I am using a Packetflux Synch to synch the BH Master.

The elevation is like this:

I hope you can advise me of more possibilities to make this work.

Or would you advise, 2400BH20/5400BH20 instead?

Bandwidth is like Internet up to 1mbps + frequent viewing of up to 6 IP Cameras from the other side.

Here is my Option B, making it into 2 Links/Hops:

This will make a 14mile and 6mile hops, from the original 18.06 direct link.

Have you done a spectrum analysis to see what the noise levels are across the 5.7 band?

I will do and post screenshot again.

Made it work already.

I have an 18.9 mile link with 2X running at 99%/99% link test. This is using Wireless Beehive Reflector Dishes. I get about -72dbm. Been up for years now.

Jerry, how are you determining the size of the Fresnel zone on these links?

Here are the calculations for the Fresnel zones.

http://en.wikipedia.org/wiki/Fresnel_zone

Remember, Fresnel is cylindrical so F1 (and the other F) are all around the path; above, below, left, right, odd angles.