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[FIXED] BMEWS Showing an Area of Uncertainty in Both Range and Azimuth

Posted: Tue Mar 14, 2023 5:23 pm
by bsq
See attached save.

Not happy at all about this behaviour from these radars. If you accept that down range, the beamwidth might be an issue (1nm for every 60nm down range for a 1 deg effective beamwidth), the range uncertainty of a pulsed radar should not exist (at least to the degree it does in the save).

If you turn Fylingdales back on instead of just relying on Thule, the data sharing should resolve the ambiguities from each radar (I would have thought).

Range should be accurate to the effective received pulse width (in the order of 100's of metres not the many kilometers shown in the save). Pulse width (actual or received) may not be modelled, but its effect should be. This may effect more than just the BMEWS types, but it is all I have tested here

(edit... posted this as an issue in Tech Support, but oddly it's showing here in the main forum :!: )

Re: BMEWS Showing an Area of Uncertainty in Both Range and Azimuth

Posted: Thu Mar 23, 2023 3:34 pm
by Dimitris
Logged #14940

Re: BMEWS Showing an Area of Uncertainty in Both Range and Azimuth

Posted: Mon Mar 27, 2023 6:00 am
by Dimitris
Consulted on this with someone far more knowledgable than me on this subject:
Rres = c * τ /2 with c = 300 000 m.s and τ = 0,008 s (for BMEWS, according to Google, so your mileage may vary), hence Rres = 1200m
"If you turn Fylingdales back on instead of just relying on Thule, the data sharing should resolve the ambiguities from each radar"
That would depend on how the two radars are interconnected. Maybe at the C2 level, but given the speed of the tracked objects and the physical distance between both radars, track merging is probably hard to do since even a relatively low latency would yield large position errors
At a higher level: what is the practical effect of this supposed discrepancy ?

Re: BMEWS Showing an Area of Uncertainty in Both Range and Azimuth

Posted: Thu Apr 06, 2023 10:34 am
by bsq
Dimitris wrote: Mon Mar 27, 2023 6:00 am At a higher level: what is the practical effect of this supposed discrepancy ?
Possibly none, but it is not consistent with how other in-game radars work. I sent you a PM example with the rules of thumb we use to determine minimum range and range discrimination (and thereby ambiguity).

I guess it all depends on why the BMEWS types are in the game?

Re: BMEWS Showing an Area of Uncertainty in Both Range and Azimuth

Posted: Sat Jan 06, 2024 7:45 am
by Dimitris
I tested the Spoon Rest radar with the current pubic version, and with regards to generating an AOU due to its imprecision, it seems to work as expected: https://imgur.com/a/aLHRY04

I also had a look at BMEWS radars and they seem to be working as expected, the longer-ranged ones generating AOUs (which still providing speed) and the shorter-range "battle management" ones providing precise tracks.

So this has probably been sorted by recent tweaks & fixes.