The Mega-Mesh Algorithm is leveraged to connect meters within a Mesh Network (updated from SignalPro v9.0.0). This Algorithm allows for the use of multiple modulation types to accommodate more complex calculations.
Modern radio networks can use versatile radio hardware that can Mesh using different modulation schemes to connect. The modulation layer feature of Mega-Mesh is designed to take advantage of the fact that the meshing radios can connect using different modulation types.
The improved capability (from v9) gives the user the ability to make plans that connect each meter using the most appropriate modulation layer.
Instead of just connecting meters based on one set of meter types in one pass, the calculation will attempt to connect any unconnected meters using successive modulation layers. Some new additional items in the “metertypes” table layer allow each modulation layer to have more complex rules for the connections between each of the the meter types.
This enhancement is designed to be downward compatible with project files from older versions of the software. Old projects will update automatically with settings that will maintain the same calculation rules that were run in older versions. If the user doesn't need the new features the basic meshing will still work as before.
The new modulation feature allows meters of a given type to connect using more than one modulation scheme. You can access this feature by pressing the Modulation Settings button from within the Run Mesh Studies dialogue:
Here is an example of how this new feature could be used:
For strong short range connections the solution could connect with the highest data-rate modulation in a first pass, but a latter modulation layer (typically with a lower data-rate, but higher link-budget) would allow for connections over more difficult terrain or at longer distance.
In the original mesh tool, the meter types are simply described by the radio link budget items, like antenna gain, power, threshold that can be found in the meter Types tables.
The user sets up various modulation types and the meshing calculations are done successively in each modulation layer using a sequence setup by the user.
Instead of having just one meters type table, the software can now have multiple metertypes tables. The original meter types table becomes a master list that has to have all the metersTypes in sequence as was the case for the original meter types table, however the other modulation layers can have entries for any subset of the masterlist.
The latter version of the mesh tool "routing" algorithm was designed to connect up meters (or radios/devices) to routers (gateways) using the paths with the lowest hopping possible. Using more than one modulation pass in the calculation means there is a lot more flexibility in designing the network. Having the ability to use multiple modulation types better models the routers used from larger vendors. A secondary long range modulation pass will enable the designer to get a much better view of how well new hardware will work in the field without having to do any hand work to connect the long ranged meters. When a second pass is run, any of the meters connected in the first pass are potential parents for the unconnected meters remaining. However there are also cases where a given meter could be connected with a stronger signal at a higher hop count.
Also to note this algorithm specialized settings to adjust the tradeoff between keeping strongest links, and using the lowest hopping, which are especially applicable to planning the connection of leaf nodes.
The original meterTypes File is replaced with a directory of meter Types files. To use multiple modulation types the following applies:
In the original mesh software the radio properties were described by meterTypes table, which was kept in a file called: <project_directory>\\SmartGrid\\MeterTypes.csv.
In the new version there is a directory: <project_directory>\\SmartGrid\MODDIR that will contain multiple meterType tables, one for each new modulation type.
The original meterTypes file becomes a master list of all meter types, and upon opening an old project it will be copied to the MODDIR directory, as the masterlist.
The masterlist should not have any gaps(missing meter types) and represents all the possible meterTypes you will have in your project.
When the new software is first used on an older project, a copy of the old meter type list is copied to the MODDIR directory and saved as the masterlist.
The other modulation meter type lists are also kept in that directory. Each modulation type has its own meterTypes file, saved in the MODDIR directory. The only constraint on those types is that any meter type number must also be (their main index) in the master list.
With the master list if you delete a meter type a new one will be generated to make sure meterTypes have no gaps in the meterType indexes.
When you make a new modulation type, a copy of the master, or any other meter type list could be your starting point. You are allowed to delete meter types, and have gaps of index within the modulation list as they do not need to be sequential as does the master list. The effect of having multiple modulation types is that you can select which modulation layers run, and also in what sequence, the algorithm tries to connect up each meter.
When running the meshing there is an option to use the master list for the first pass before you run any other of the modulation passes. This checkbox can be found within the Modulation Pass Settings Dialogue. Having this feature enables you to check for consistency between the old and new calculations.
Turning Off the New Features
In the dialog "Single Router Calculation Settings" is a switch labeled "Limit range base on meter type". When this switch is turned off the calculation will proceed as it did in previous versions where the range limits to compute propagations are set for the various "Router, repeater, meter" combinations. With the switch on, the ranges are set by using the range limits set up for each meterType at each modulation pass. This switch applies to all modulation layers. It must be turned off if you want to do calculations with a given meter type having a longer max range for a particular modulation pass.
In the main "MegaMesh Scalable Mesh Studies" Dialog, under “Run Mesh Studies” is a button labeled [Modulation settings...] Use this to bring up the Modulation pass settings dialog.
Figure 1) Modulation pass settings dialog.
"RunMasterMeterList" Shows “toggle to turn on or off the preliminary run of masterlist. The masterlist is there to provide backward compatibility with the old software version.
"[Move-Up],[ Move-Dn]" allows you to control the run order of the modulation passes that are checked. The modulation passes are run in sequence and a meter will be hooked up in the first pass that can connect it and can then be used to hook up other meters in later modulation passes.
"Display number for spreadsheet" sets an integer value that will appear on links and in the spreadsheet.
"Line style" and "link color" control stippling decorations on drawn links.
"Relative router gain" allows you to adjust additional power or loss for how the external Transmitter is treated by each modulation scheme.
"Db per hop tradeoff for initial connection" when connecting up meters to those previously connected from an earlier modulation pass, using the next modulation type in the list, this parameter is used to balance the trade-off between parents with lower hops, and parents with stronger signals.
"Optimize coverage with best signal for leaf nodes" when this feature is on, all leaf nodes are connected in one final pass without regard to hoping.
"Max signal difference for capacity balancing" The leaf node optimization tries to connect as many meters as possible given the fanout and distance constraints. When the “Optimize coverage with best signal for leaf nodes” feature is used this parameter allows a max loss in signal to make a connection at a less used source meter.
"Find strongest parents allows the user user to choose to connect with stronger connections rather than the usual lowest permitted hop count. This feature allows a modulation pass to hook up meters using multiple iterations. That calculation starts by hooking up only the strongest connections and then gradually hooks up less strong connections. This feature can produce results with much higher hopping that when the feature is not used.
When "Limit range based on meter type" is turned off, lets a user set max range limits for propagation to the combinations router-meter, router-repeater, repeater-repeater, repeater-meter, and meter-meter. However users now have the option to set the ranges on a per meter type and per modulation basis. In the “single router calculation settings dialog” accessed by the “Algorithm settings” Button on the viewing window, is the option to “Limit range based on meter type”.
When unchecked the old parameters to limit the meshing calculation ranges are used. When checked the values that depend on the metertype settings for each modulation "pass" are used for calculations. There are three new range limits for each meterType. There is a range limit for connections per modulation type back to the router. If this is set to zero the router will not connect to the meterType in the calculation pass for that modulation scheme. There are also range limits for each meterType as both parent and child when connecting to other meters..
For example; if MeterType A is connected to meterType B, with A as the parent(closer to the router, or lower rank) then the max range would be the minimum of the A-(range as parent) and B-(range as child). By setting the meter type as child range to zero, you can make it so that meterType is only used as a parent in that modulation pass.
A previous addition to the meter-Types table was a quantity called Fanout.
Fanout is used to limit the number of downstream devices that a radio can connect to.
When the fanout is zero the radio is a leaf node(like a battery operated water or gas meter) and can not connect to any other radios.
When the fanout is set to -1 it is not used in the calculation and the radio is not constrained in how many direct connections it can make.
The Fanout controls the number of children to a given type.
Another special case for the fanout setting is the value of -2. When a Fanout is set to -2 the modulation type will take into account the fanout set for the previous layer and the number of children devices that each meter has. You can think of -2, as a "continuation mark" that lets you have a combined Fanout of more than one layer.
Suppose you wanted to setup rules to create a PMP type systems embedded in an ordinary meshing system: For example; if you wanted to use electric meters to connect up water meters you could have both a short range modulation pass, and long range modulation pass for the electric to water meter connections but the electric meters would have used the first fanout value to limit the children type for the devices connected in these two modulation passes, the second pass would only connect meters that didn't violate the fanout limit for the combined layers.
Similarly you can prevent any new connections to a meter, by setting the Meter Type as child by using zero(km) for the "meter type as child range". Setting the range-as-parent of a meterType to zero in a modulation scheme also prevents that type from being a parent in that modulation scheme. Also setting a router-range of zero prevents the meter type in that modulation layer from connecting directly to a router in that layer.
New rules allow more complex Mesh Topologies:
An example of embedding a point to multipoint links to serve water meters inside the regular meshing topology.
Suppose you wanted to allow an embedded point-to-multipoint system inside your ordinary mesh network for electric meter. Two modulation types are needed, the first can be used to create the regular mesh system including the repeaters and electric meters, but not the water meters. The second modulation pass can be used to connect the water meters back to the electric meters but with no additional connection between the electric meters.
For the first modulation type, the water meter type can be deleted from the modulation type or else you can set it so that the fan-out is zero, and the router and child range limits are set to zero. This will make it so that modulation (gas or water) won't connect in the first modulation pass.
In the second modulation pass the permitted connections between the Electric and water meters need to be set up. If you want to limit the electric meters to only service a finite number of water meters, you must set the fan-out to that number. The max range of connection of the Electric and water meters will be the minimum of the range for the electric meter "as parent" and the range for the water meter "as child". Assuming you have provided connections for the Electric meters in previous layers, set the router range to zero for the electric meters and if you want the water meters to only hook up to electric meters, also set its router range to zero. Set the fan-out of the water meter to zero, or the range of the water meter as parent to zero, to make sure the water meters act as leaf nodes. Also to prevent electric meters from serving other electric meters you can set the electric meter "range as child" to zero.
There is an additional choice for hooking up leaf nodes. The switch "Optimize coverage with best signal for leaf nodes" allows all the leaf nodes to be hooked up after all the candidate serving meters have been found. Ordinarily in mega-mesh any meters are automatically hooked up with the lowest hop count possible. However with leaf nodes it makes sense to hook up all the leaf nodes in a modulation type at the same time to optimize both, the maximum number that can be connected and to use servers with a higher hop count if they can make a stronger connection to the leaf node.
Also the user can hook up leaf nodes in more than one modulation pass. For example if you want to have a separate pass to connect up leaf nodes with a modulation pass that has a larger link budget to make longer connections possible you can do this. In case you want a successive modulation pass to inherit the fanout properly from a previous modulation pass, use a value of -2 for the second layer. This choice makes it so the layer with fanout -2 will create a solution where the layers will treat the fanout of the previous layer as a limit and the total connections to the parents will not exceed the fan-out setting in the prior layer.