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Snaptrap
05-02-08, 05:33 PM
What I need to know is what the arc is in a radar or sonar sweep?

Soundman
05-02-08, 05:44 PM
One single sweep is 360 degrees. Of course this sounds too obvious, but perhaps you need to further define your question. Edited: On further thought I suppose the question is, ....if you are maneuvering the radar, and hold it stationary, say at zero degrees forward, what is the field of view, so to speak?

Snaptrap
05-02-08, 05:51 PM
So basically the arc is the scan range in degrees.

Soundman
05-02-08, 06:07 PM
Firstly, what type of radar are you speaking of ? Surface search? If so, it is dependent upon which setting....Continuous sweep or, or the other mode (can't recall the proper term...brainfart) when your aim the radar on a specific bearing.

Soundman
05-02-08, 06:12 PM
You can manually point the radar (surface) in any direction you wish, IF that is what you have selected at the radar station. What that field of view is, I'm not certain. Certainly, someone will pipe in here with that answer. My best guess....20 maybe 30 degrees. It's pretty narrow.

Soundman
05-02-08, 06:19 PM
So basically the arc is the scan range in degrees.

No...how wide the arc is (field of view) will remain constant as far as degrees go, no matter what range is selected.

Ducimus
05-02-08, 06:40 PM
To the game, a radars arc, is how wide the radar beam is that is being projected. (if were talking about the statistic that i think we are :roll:) a 10 degree arc is a narrow beam, a 20 degree arc is a fairly wide beam.

I know i included this info in TM, because i was looking for statistics to make the various radars seem more distinct when their info is viewed.

Snaptrap
05-11-08, 10:33 PM
So the wider the arc the better the sensor sweep?

Nisgeis
05-12-08, 04:57 AM
So the wider the arc the better the sensor sweep?

If you're playing with contacts on the map, it doesn't matter at all, as the map is super accurate, regardless of the accuracy of your sensors.

It only matters if you are playing manually and trying to determine a target's bearing from sonar or radar alone. If you imagine a cone going out pointing in the direction the sonar head is pointing, then that's the bearing you will pick up sound from. If you have a target at a relative bearing of exactly 0, then your sonar will start to pick up its noise at about 351 degrees and it will get louder, reaching a peak at 0 degrees and then dropping off until it is no longer audible as the sonar sweeps off to 9 degrees. This means that the sonar picked up a single target over a bearing range of 19 degrees. This is called the bearing resolution and in this case is 19 degrees. If you had a better sonar set with a bearing resolution of 11 degrees, you'd start hearing the target between 355 and 005 degrees. If you had a super accurate sonar, with a bearing resolution of 1 degree, you'd only hear the target between 355.5 degrees and 0.5 degrees. You can work out the bearing of a single target by measuring what range of bearings you can hear him in and then picking the centre of the bearings given, but this becomes very difficult when there are multiple targets within the bearing resolution, so the better (smaller bearing range) the resolution, the more useful it becomes.

Radar is different and in 1.4 (haven't checked in 1.5) and doesn't seem to work like sonar, it's all a bit odd really. You'll start getting the target a few degrees before the target's actual bearing and it will stop 'seeing' the target exactly at the target's bearing, or a bit before if it is to the port or starboard. I'm not sure if it's meant to be like that, but it's not modelled the same as the sonar arc is, it appears to have the arc projected off to the side of the radar antenna's bearing.