Thread by @steffanwatkins

Are you familiar with how MLAT works? I have a dataviz/infographic/GIS visualisation challenge that I'm coming to the realization I do not have the skills to adequately convey in a graphic, and am looking for some help.

Basically, I'd like to show what Syria (say) would look like with a robust MLAT-gathering network of Mode-S receivers in an isometric 3D representation, showing overlapping coverage cones, and the density of receivers needed for border or nationwide MLAT, if that makes any sense.

I picked Syria because the coverage in that area of the world isn't robust and we miss a lot of the aircraft coming in and out of the country, as well as neighbouring Iraq and Turkey.

Unfortunately I don't know what cities and villages have robust internet access and power, so I don't know in a practical sense where receivers could be located.

Making a tidy checkerboard grid isn't helpful, I'm trying to show where "realistically" receivers would need to be positioned.

It's a paper exercise, since I don't have the connections needed to get Syrians to set up such a network either.

Multiple receiver densities could be explored for geolocation of high, medium, and low altitude Mode-S targets.

Altitude and line of sight of the receiver needs to be taken into account too.

I think this is similar to visualizing radar coverage for air defence, or mobile phone cellular network planning; neither of which I have any experience with.

For that matter, it would probably be similar to planning any kind of line-of-sight microwave network, with the complication that each of the sites favourable to an antenna, also needs someone willing to host a receiver with internet. Larger pop = better chances to find a host.

Picture every village/town/city in a country, with internet, having an omnidirectional antenna that picks up the Mode-S transponder signal from an aircraft's above a certain altitude for a certain distance. Let's say 100km at 40,000ft.

Only (Mode-S) aircraft within line of sight (say 100km for ease of math) of FOUR receivers are geolocated using multilateration (MLAT). The distance apart and locations of those receivers allows the plane to be roughly geolocated.

While a grid or hex pattern spread out would be pretty in a blue sky paper exercise, practically I'm suggesting dropping push-pins on every urban settlement of a certain size and putting a 100km radius around them, and extruding that visually to cones, originating at the receiver

The idea is to show if at 40,000 you seem to have MLAT coverage over an area in 2D, at 10,000ft you have peaks and valleys of coverage between 4 receivers where 1,2, or 3 have LOS in 3D.

Many people are interested in the aircraft transmitting and identifying their own location, I'd like better coverage of the aircraft which aren't volenteering their location, which include all sorts of interesting clientele who would rather not be tracked, but certainly can be.

MLAT does just that, but we need
1) internet
2) power
3) locals to be interested in making it happen

Only one or two more #ADSBexchange receivers in #Iceland 🇮🇸 would show people (more effectively than I can) the regular deployments of 🇨🇦 #RCAF CP-140 Auroras to #Keflavik 🇮🇸.