SeaQueen
Posts: 1451
Joined: 4/14/2007 From: Washington D.C. Status: offline
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Almost there. The ability of a radar to resolve range depends on the pulse width of the radar set. Nothing else. Beam width (which in CMO/CMANO is synonymous with antenna gain) what determines a radar's angular resolution. Now... why does a track get better with time? Two things: 1) Kalman filtering (this is a mathematical technique involving matrix multiplications and Bayes theorem). It's way too complicated to explain here today, so... go read about it somewhere. There's got to be an engineering dork around here somewhere. Not sure if Command does this, but if it doesn't it'd probably make D's life easier. 2) Because angular resolution is an angle, 3 deg resolution is worse at 300 NM than it is at 2 NM, because that same angle subtends more or less space at different distances. That's just geometry. Also Doppler radars might be able to discern range a little better using the Doppler shift and some signal processing, but this is the basics. With that, the final dogfight scene in TOPGUN: https://www.youtube.com/watch?v=jqfXXaOisKo Is actually potentially reflective of a real phenomenology (awesome!). Aircraft sufficiently closely spaced MIGHT be able to fit within what's called the "resolution cell" of the radar (which the box of angular width equal to the beam width, and length equal to the pulse width times the speed of light). Since the aircraft are both in the same resolution cell, the radar thinks they're one thing! This is important for sneaky MiG-28s looking to fire Exocet anti-ship missiles from 100 miles away for no obvious reason than the fact that they're MiGs, and they're black with a red star and pointy. You know how they are. Here's a question! Could a "MiG-28" (i.e. F-5) carry an Exocet anti ship missile? Maybe the centerline? What about ground clearance? I need to ask someone about that. At any rate, here's an explanation of the "resolution box" which is slightly more nerdy. https://www.radartutorial.eu/01.basics/The%20resolution%20cell.en.html I'm not sure Command really captures that phenomena directly but there's database entries to get a similar(?) effect. Perhaps the developers can comment? quote:
ORIGINAL: Dragon029 For the length of a detection box (which shows the minimum and maximum range to the target) you're talking about the range resolution. This is how accurately a radar can measure the time that it's taken for a radar signal to reach the target and reflect back. To measure this time, a radar needs to detect key identifying features in return signals; usually it will measure things like the rising or falling edge of a pulse. If the radar gets a weak signal return and/or there's a lot of echos / multi-pathing then it'll have a number of potential distances to the target. A long radar wavelength means a low frequency as well, which typically results in pulses that have smoother rising and falling edges to their pulses, making the exact measurement of when a pulse arrives at the radar a bit more ambiguous. This value should improve over time as a target gets tracked / detected multiple times, but narrow down the target's range can take a while, especially when there are multiple potential targets being detected.
< Message edited by SeaQueen -- 2/6/2021 12:38:36 PM >
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