Topics

signal strength simulations


Cliff Dorr
 

I've recently joined the group to learn more about the efforts in getting Mesh Networks up and running in our region.  I've been thinking of setting up a node, but I don't have many potential connection possibilities as I see it.  I live in Lake Oswego and, in looking at the map, I see a few potential nodes to connect to from my location.  The most likely to yield good results is KG7OXP in West Slope.  Does AREDN or any other source have a signal strength simulation app based on topoggraphy etc?  I would appreciate any ideas anyone might have to get a better handle on the possibilities for my location.
Thanks
Cliff
KF7KU


Brett Popovich KG7GDB
 

HI Cliff,

Welcome to the mesh!

We tried a variety of simulation tools, but have found that the first step is to determine line of sight (LOS) from the area you want to operate to another access point.
Read this message from the group for a technique using Google Earth: https://groups.io/g/Salemmeshnetwork/message/18

We find the viewshed view of Google Earth Pro works well for us in areas where the tree heights are rendered properly. You should be able to mouse over houses and trees and read the elevation changes on the screen.
The rule for microwaves is always "If you see them you can work them." You can find likely spots where signal can reach by site surveys, but you will need a node set up as a target somewhere, such as the roof of a neighbor living on a hill. We use 7m height relative to ground for modeling the view from a typical house mount. A pair of binoculars and a visual landmark will help you in the field. You need to mount your device at least 7 feet above ground or objects.

We are not limited so much by signal strength, but more by terrain and ground clutter. We have solid connections now up to 34 miles on 5 GHz for hillside sites with clear views.
Signal strength modeling tools such as Ubiquiti airlink https://link.ui.com/# use mainly terrain modeling, and give overly optimistic predictions. It may help you visualize the beam pattern of a Ubiquit Device for a given height, but the default values given assume a commercial tower installation and newest AC routers which don't work with AREDN firmware.

Don't give up if your own home QTH is unreachable by RF. These devices can also be made into a Go-Kit for portable emergency communications.
We are trying to bring mesh access points up the valley to Clackamas County near the Woodburn and Aurora areas, but are still seeking locations.
For you, it would be really great to get together with other amateur operators in Clackamas and Washington County to try to get some access points near you and work your way back. Anyone can join the mesh with the AREDN.

We have mesh tunnel connections to Jeff, KE7OEK, and he has 3 MIkrotik LDF5 radios which can be mounted on Slimline DirecTV satellite dishes. These have a 20 mile range. As you mentioned, Stafford KG7OXP is also on the mesh. They are both residing in Multnomah County, but you will want to contact them because they are your closest connections to the mesh at this time. There have been ongoing efforts in Washington County by hams working at Intel campuses. We would really like to connect to them, too.

Hope that helps. Good Luck!
73,
Brett, KG7GDB


Cliff Dorr
 

Brett, 
Thanks for the all the info.   I’ll  pursue this locally and hopefully find some interest.  I did take a look at Google earth.  It looks like a good first approximation but, in my case at least, it’s showing good coverage in areas I know I can’t reach given terrain obstructions etc.  I think your suggestion of a field survey with a pair of binoculars might be the best start.  
I’ll keep monitoring the group for info and “interest” in my area.
Thanks again for the info.
Cliff
KF7KU

On Sep 11, 2020, at 10:58 PM, Brett Popovich KG7GDB via groups.io <brettkp@...> wrote:

HI Cliff,

Welcome to the mesh!

We tried a variety of simulation tools, but have found that the first step is to determine line of sight (LOS) from the area you want to operate to another access point.
Read this message from the group for a technique using Google Earth: https://groups.io/g/Salemmeshnetwork/message/18

We find the viewshed view of Google Earth Pro works well for us in areas where the tree heights are rendered properly. You should be able to mouse over houses and trees and read the elevation changes on the screen.
The rule for microwaves is always "If you see them you can work them." You can find likely spots where signal can reach by site surveys, but you will need a node set up as a target somewhere, such as the roof of a neighbor living on a hill. We use 7m height relative to ground for modeling the view from a typical house mount. A pair of binoculars and a visual landmark will help you in the field. You need to mount your device at least 7 feet above ground or objects.

We are not limited so much by signal strength, but more by terrain and ground clutter. We have solid connections now up to 34 miles on 5 GHz for hillside sites with clear views.
Signal strength modeling tools such as Ubiquiti airlink https://link.ui.com/# use mainly terrain modeling, and give overly optimistic predictions. It may help you visualize the beam pattern of a Ubiquit Device for a given height, but the default values given assume a commercial tower installation and newest AC routers which don't work with AREDN firmware.

Don't give up if your own home QTH is unreachable by RF. These devices can also be made into a Go-Kit for portable emergency communications.
We are trying to bring mesh access points up the valley to Clackamas County near the Woodburn and Aurora areas, but are still seeking locations.
For you, it would be really great to get together with other amateur operators in Clackamas and Washington County to try to get some access points near you and work your way back. Anyone can join the mesh with the AREDN.

We have mesh tunnel connections to Jeff, KE7OEK, and he has 3 MIkrotik LDF5 radios which can be mounted on Slimline DirecTV satellite dishes. These have a 20 mile range. As you mentioned, Stafford KG7OXP is also on the mesh. They are both residing in Multnomah County, but you will want to contact them because they are your closest connections to the mesh at this time. There have been ongoing efforts in Washington County by hams working at Intel campuses. We would really like to connect to them, too.

Hope that helps. Good Luck!
73,
Brett, KG7GDB


Cliff Dorr
 

Brett, 
Thanks for the all the info.   I’ll  pursue this locally and hopefully find some interest.  I did take a look at Google earth.  It looks like a good first approximation but, in my case at least, it’s showing good coverage in areas I know I can’t reach given terrain obstructions etc.  I think your suggestion of a field survey with a pair of binoculars might be the best start.  
I’ll keep monitoring the group for info and “interest” in my area.
Thanks again for the info.
Cliff
KF7KU

On Sep 11, 2020, at 10:58 PM, Brett Popovich KG7GDB via groups.io <brettkp@...> wrote:

HI Cliff,

Welcome to the mesh!

We tried a variety of simulation tools, but have found that the first step is to determine line of sight (LOS) from the area you want to operate to another access point.
Read this message from the group for a technique using Google Earth: https://groups.io/g/Salemmeshnetwork/message/18

We find the viewshed view of Google Earth Pro works well for us in areas where the tree heights are rendered properly. You should be able to mouse over houses and trees and read the elevation changes on the screen.
The rule for microwaves is always "If you see them you can work them." You can find likely spots where signal can reach by site surveys, but you will need a node set up as a target somewhere, such as the roof of a neighbor living on a hill. We use 7m height relative to ground for modeling the view from a typical house mount. A pair of binoculars and a visual landmark will help you in the field. You need to mount your device at least 7 feet above ground or objects.

We are not limited so much by signal strength, but more by terrain and ground clutter. We have solid connections now up to 34 miles on 5 GHz for hillside sites with clear views.
Signal strength modeling tools such as Ubiquiti airlink https://link.ui.com/# use mainly terrain modeling, and give overly optimistic predictions. It may help you visualize the beam pattern of a Ubiquit Device for a given height, but the default values given assume a commercial tower installation and newest AC routers which don't work with AREDN firmware.

Don't give up if your own home QTH is unreachable by RF. These devices can also be made into a Go-Kit for portable emergency communications.
We are trying to bring mesh access points up the valley to Clackamas County near the Woodburn and Aurora areas, but are still seeking locations.
For you, it would be really great to get together with other amateur operators in Clackamas and Washington County to try to get some access points near you and work your way back. Anyone can join the mesh with the AREDN.

We have mesh tunnel connections to Jeff, KE7OEK, and he has 3 MIkrotik LDF5 radios which can be mounted on Slimline DirecTV satellite dishes. These have a 20 mile range. As you mentioned, Stafford KG7OXP is also on the mesh. They are both residing in Multnomah County, but you will want to contact them because they are your closest connections to the mesh at this time. There have been ongoing efforts in Washington County by hams working at Intel campuses. We would really like to connect to them, too.

Hope that helps. Good Luck!
73,
Brett, KG7GDB