I’m trying to figure out how this bad ride works, but I’m in over my head. I’m trying to use it to get an idea of where I can build 5.7GHz BH links. Can someone give me a sample configuration for the networks page.
I plotted the test locations. Figured that part out, I think.
For starters I entered the frequency range of 5175-5860MHz (the entire range listed in the spectrum analyzer. Selected vertical polarization, temperate continental climate.
The systems tab is where I get a bit lost. I entered 23dBm for the transmit power (from the BH UG), and 7dBi for antenna gain. Left the rest at the defaults, -119dBm Receiver threshold, etc.
Is this even close?
I’m assuming on the radio link output the innermost football is the 1st fresnel zone, the next two the 2nd, and third.
What should I be looking for? Or maybe the question I should be asking is, where is a good source for a decent background in RF theory?
Perhaps it would be easier if I just included my test radio link.
Greetings,
First, let me point you you to a great source of documentation:
“Greg Bur alternative source of documentation” link from the RMW website: http://pizon.org/rmw/index.html
The relationships of Networks, Systems, and Units in RMW is critical to using RMW effictively.
A Network is a grouping of all of the radio equipment that works together.
A System is a spesfic piece of radio equipment
A Unit is a location (IE: tower, subscriber, etc)
A Network is a collection of Units.
Each Unit is a member of one or more Networks.
Each Unit is assigned a System in its Network membership.
I have one network "Canopy 900"
I have four systems “AP 12dB”, “SM 12dB”, “SM 9dB Yagi”, “SM 13dB Yagi"
I have many units: the tower, and each subscriber
All of the units are members of the “Canopy 900” network, and each unit is assigned a system according to what equipment is at the unit (AP, SM, with Yagi, etc)
The more accurately you enter your System’s specs, the more accurate RMW will be. Most of the important values you can find easily:
Transmit Power: this value you set in the configuration page of the Canopy EQ
Antenna Gain: I know you know this
Receiver threashold: That is in the Canopy manual. (-90) on my 900 gear
Line Loss: if Nonconnectorized, its zero. If not, you’ve got some research to do
So, it looks like you’ve got to tweek your System specs alittle.
On to the profile you posted:
Yes, the inner “football” is the first fresnel zone; the middle is the second, outer is the third.
The two fields at the top of the profile that are going to give you the most valuable info are “Rx level” and “Fresnel”.
“Rx level” is the signal strength that RMW projects you will have at the slave site
"Fresnel” tells you what clearance you have of the first fresnel zone; basically “1” means 100% of the first fresnel zone is clear, 0.7 means 70% of the first fresnel zone is clear. WIth 18.5, you’ve got plenty of room.
According to “Rx Level,” you’re only going to get -97 dB at the customer’s location: that is obvisously below the reciever threashold of the Canopy gear. Since your threashold is set to -119.4 dB, RMW shows green.
Also, if you are truely using 7 dB antennas then you should set your TX power to higher then 23 dB. Your EIRP is less then a watt! In the US, the FCC alows 4 watts. Get that baby up there, man.
You’re on the right track. Just remember, RMW (or any radio propagation software) is only as accurate as the data you give it.