Remote Mlat - an Overview

[Anmer]

With some help from satcom and Bev from COAA, I'm beginning to get a clearer understanding of Remote Mlat. However, there's still some confused debate over on the AirNav Forum.

A Ground Station is an approved source of Mlat positional fixes.  At this time only the SBS-1 can provide the required data for a Ground Station. The AirNav RadarBox cannot and the still to be released Aurora's capability is unknown. A Ground Station is by default a Master User.

Ground Stations need to provide PP with "raw data" from the SBS-1.  This means decrypted data for which a "patch" is required.  There are two patch versions, one for USB users and a different one for those using ethernet.  The ethernet option also needs multiple access to the SBS-1 (one for the patch, the other for Basestation).  If the SBS-1 uses the SBSnet multiple access is included with the SBSnet Pro service.  For Kinetic supplied ethernet (either the retrofit EM or SBS-1e model range) the Multi-EM software from www.Jetvision.de is required.

In return for being an approved Ground Station and sharing 24/7 or at least a good part of each day on a regular basis, the Mlat option if free. Otherwise one has to pay ?12 a year to be a (non-Ground Station) Master User which allows one to instigate an Mlat plot for a nominated aircraft and benefit from Remote Mlat plots.  From what I can ascertain there is no approvals process for Master Users other than checking the credit card is good for ?12!

A (non-Ground Station) Master User designation is available to anyone who is willing to pay.  This includes RadarBox customers and those without a ModeS receiver.  Or does it?

Having read the 5.4.6 Release Note again, I had a few queries about Remote Mlat:

This is an entirely new feature whereby users who are GS+MU can perform continuous automatic Mlat requests when their machine is not otherwise occupied.  The option "Allow Remote Mlat" is in the Options..I/O settings dialog in the Input section.

If this option is checked, then the server will invite PlanePlotter to perform an Mlat on a target that is "Mlattable" but not currently being "Mlatted".  The request will only be made if the machine is not in use (no recent user interaction with PlanePlotter), no other Mlat is currently in progress and only if the instance of PP is currently receiving messages from the "positionless" aircraft in question.

The intention is that, with enough users choosing to enable this option, most potentially Mlattable aircraft will start to appear on the charts of Master Users without users themselves having to initiate the Mlat requests.

The provision for manual Mlats remains unchanged.  This option gives PP the chance to do Mlats without the user asking for it.

Does this mean that automatic Mlat requests can only be driven for locally received data, either from an SBS-1 or RadarBox feed?  In otherwords, if you are using PP without a data feed, Remote Mlat doesn't work?

Following on from this, does the PP server "share" other PP users Mlat plots?  Or will the PP user only see Mlat plots that the PP server has initiated on the local instance of PP?

Well, having communicated directly with Bev at COAA, he assures me that Remote Mlat plots are available to everyone with a Master User status, either approved Ground Stations or those who have paid their ?12 a year.

The PP server will initiate Remote Mlat plots for all approved Ground Stations with the Allow Remote Mlat option checked.  The PP server will not initiate Remote Mlat plots for non-Ground Station Master Users.  But the PP server will share all successful Mlat plots with Master Users, even if the PP Remote Mlat is not checked.  There is no requirement for Master Users to have a ModeS receiver or to be feeding PP from one.

The two key settings in the PP I/O Options is to check UDP/IP data from net to Mlat and Allow Remote Mlat to initiate Remote Mlats requests from your PC if you're an approved Ground Station.  Allow Remote Mlat does not need to be checked to view Mlat plots that others have instigated and shared via the PP server.  However you do need to configure your router to forward traffic to port 9742 on the PC running PP.  I would also recommend extending the Omit aircraft after timeout under Chart options to 5 mins or more.

There is no need to check SBS1 Raw Data unless you can feed SBS1 raw data and wish to be validated as a Ground Station.

Here is Bev's latest reply to me:

The whole point of Remote Mlat is that, since Mlat results are indeed shared through the sharing system, everyone benefits if GSs check the Allow option.

Nobody is excluded.  Even those who are paid-for MUs with no receiver will see the results of all the Remote Mlats plots that the PP server has initiated for approved Ground Stations.

I also read into the above that the quantity of Mlat plots will increase as more and more Ground Stations allow the PP server to instigate Remote Mlat requests and share the results.

Sorry for such a long post, but the topic has become a little clouded  

Once again my thanks to satcom and Bev.

[Anmer]

I was sent a PM earlier asking what more could Mlat offer and is it easy to setup.

If you become an approved Ground Station (free) or upgrade PP to Master User, Mlat will enable you to track aircraft that don't send positional data.

See this screenshot, just taken.  It shows a number of Flybe aircraft as well as a PUMA and VC10 that wouldn't appear on a Basestation or RadarBox map.  All of these plots are Mlat aircraft, otherwise non-positional.

Mlat is fairly easy to setup but the router needs port 9742 "opened" for port forwarding and, depending on the router, this can be tricky for some.