Upcoming Updates Video (19 Aug) on Spotlight Scan Radar Mode

[GrEaSeLiTeNiN]

I watched Wag's recent (19 Aug) upcoming updates video which included Spotlight Scan Radar Mode here.

But I am not sure how it is to be used exactly or whether it is useful to have the cursor over the target with TMS forward for > 1 sec, because the target will lock up anyway upon immediately TMS release without having to wait 1 sec, ie. a regular TMS Up would have done the job. Or do you do this only when the target, although detected, isn't locking up (is there such a possibility?) and having the cursor over and holding TMS up (> 1sec for Spotlight) will focus the radar on it in so it becomes 'lockable'?

Also, spotlight scan radar mode is already available in OpenBeta. So what is the change?

Thanks in advance 

[Rhinozherous]

18 minutes ago, GrEaSeLiTeNiN said:

I watched Wag's recent (19 Aug) upcoming updates video which included Spotlight Scan Radar Mode here.

But I am not sure how it is to be used exactly or whether it is useful to have the cursor over the target with TMS forward for > 1 sec, because the target will lock up anyway upon immediately TMS release without having to wait 1 sec, ie. a regular TMS Up would have done the job. Or do you do this only when the target, although detected, isn't locking up (is there such a possibility?) and having the cursor over and holding TMS up (> 1sec for Spotlight) will focus the radar on it in so it becomes 'lockable'?

Also, spotlight scan radar mode is already available in OpenBeta. So what is the change?

Thanks in advance 

I am not sure, but could it be that we dont have to have the cursor near the target? It may be that it just locks the first tgt inside the sweep... Like in the F18. 

Edited August 19, 2022 by Rhinozherous

[RuskyV]

In theory by focusing all the radar energy into a smaller scan volume you should be able to detect a target a little further out. The radar is updating a very small area so should brute force the radar into picking up contacts bypassing filters built into the radar that would normally disregard a contact.

Others  can fill in the details.

[TEOMOOSE]

Spotlight search allow the selection of the 4-bar ±10 degree scan pattern, and it commands the FCR to search a small volume of space.

So if you cant see a target witch you know theres is one, try use the spotlight search to focus all energy on that heading. You might pick him up or get radar hits. 

Spotlight search should also be available in TWS when no bugged targets and no amraam in the air.

[falconzx]

So the doubt is: Is it just a shortcut for a scan pattern we can select already via OSB or does this scan include a forced STT lock in case the radar eventually picks something?

[greenmamba]

Shortcut. 

[TEOMOOSE]

5 hours ago, falconzx said:

So the doubt is: Is it just a shortcut for a scan pattern we can select already via OSB or does this scan include a forced STT lock in case the radar eventually picks something?

if theres a radar detection during spotlight search it will automatically initiate a radar lock. Wags says this mode helps a longer range radar lock.

Spotlight search mode has been in the sim for a long while now! Perhaps its getting the logic implemented, as the radar getting some love.

[Frederf]

It's really helpful to get 4 bars for a vertically mobile or unknown target. A lot of time you fly around in 2 bar because 4 just takes too long. When jamming indications are seen it can be helpful to burn through since you know the azimuth pretty well already.

Spotlight has a larger acquisition area than the cursor. You can use it with missiles in the air but beware it can take time away from other tasks.

[GrEaSeLiTeNiN]

I get that spotlight focuses the radar. In the video, Wags releases the hold on TMS Up in order to lock up the target. Unless a regular TMS Up would have been unable to lock that contact, the procedure is pointless. I’ll have to try the new spotlight when it comes out against far away contacts that can’t be locked up with a regular TMS Up to see if it makes a difference.

[Frederf]

It's just the natural flow because you're holding designate and slewing to find the best place to release the switch. Ergonomically it sort of how TMS release works with TGP point and Maverick track. Rapid radar energy in a small space will find stuff that infrequent radar energy won't. Plus you should have a high quality track forming from spotlight that can be tracked right away where a single search hit would have to go through a longer and fallible acquisition sequence.

[Beamscanner]

IRL Spotlight is used to rapidly acquire a target when the direction or relative position of the target is known, but your radar is not currently detecting the target. 

ie via data link track or bogey dope call. 

IRL radar detection ranges are probabilistic (typical advertised detection range is based on a 50% detection probability). Thus, getting more sweeps across the target simply means that your radar gets to 'roll the dice' as it were, many more times in a given period. 

(its probabilistic bc targets RCS fluctuates rapidly in real time; due to reflection geometries and interference) 

DCS does not use probability in its radar detection ranges... Its 100% or 0%.

 

 

Spotlight mode is not used to lock up a target that already has a trackfile on your scope. In that case it is useless. It's too bad that the video showing spotlight has them simply use it on a target the radar already sees.... smh

[Frederf]

Wanted to ask you, beyond the probabilistic aspect is there any cooperative aspect to multiple scans. Returns are not binary in themselves, there's energy and noise level to distinguish itself from. Can multiple returns which individually don't meet requirement for being a detection collectively become a detection?

[KlarSnow]

By default every detection is multiple returns integrated in these cases. Scan rates are determined by a requirement to have a certain number of pulses hit the target as the sweep goes past. These pulses are then integrated to determine if a detection occured. So in a very straightforward system 2/3 pulses that return = a target = displayed on the scope. If only 1/3 show a return, then it is assumed noise. If you slow the scan rate down (or increase the pulse rate) you increase the number of pulses getting integrated, thus increasing your SnR.

This is why STT minirasters can acquire at longer range than search, instead of a search sweep only getting say 3 pulses on target as the beam sweeps past, in STT it sweeps back and forth inside its beam width, so in a second 50-100 pulses illuminate the target. Getting 30/100 pulses returning may well be enough to establish and hold a track, whereas in sweep you may have only had 1/3 returning. The other advantage here is that in STT your cursor placement and a previous hit (if one exists) pre-sets the range, velocity, and azimuth gates and helps the radar solve ambiguities (start in the PRF without a blind zone at the cursors range, ignore ambiguous returns that are at the incorrect range or velocity from the cursors position etc...)

Spotlight is an inbetween, and the specifics may vary jet to jet, the highlight is it very quickly illuminates (think many quick re-rolls on the probability of detection dice) an area of interest, if you just do the math, with every single pulse being even on detection. In a normal RWS or TWS sweep where the target is illuminated every few seconds, that means for example if you are at a range where the Probability of Detection is .3, then you are getting a single return every third sweep. THat may result in an intermittent contact that fades before it can update, or you just arent getting enough hits as the beam revisits to even make a contact show on the radar. 

In spotlight in the same amount of time you will have many revisits, this is really the primary purpose of spotlight, you have a cued search, which you can center around an intermittent or weak return, and then very quickly potentially get several hits which you can then transition into a track (STT) mode.

[GrEaSeLiTeNiN]

So am I right to understand that in DCS, as long as the non jamming target is in your scan volume, you will pick/lock it up 100% (and if not 0%)? Which then makes the spotlight option in the sim a little unnecessary other than it being a 'shortcut' and useful for burning through a jamming contact?   

Edited August 27, 2022 by GrEaSeLiTeNiN

[Dragon1-1]

It's also useful if you want to lock onto a contact you otherwise only see on datalink, or an intermittent one. Assuming you're not searching in 4-bar, it's also a quick way of expanding your scan zone vertically without changing antenna angle.

[henshao]

Based on my knowledge of the Eagle, I would expect spotlight in the Viper to be stabilized in space, which combined with automatic acquisition could be very useful when the workload starts climbing

[Beamscanner]

13 hours ago, Frederf said:

Wanted to ask you, beyond the probabilistic aspect is there any cooperative aspect to multiple scans. Returns are not binary in themselves, there's energy and noise level to distinguish itself from. Can multiple returns which individually don't meet requirement for being a detection collectively become a detection?

No. 

This is a misconception many RL pilots have. 

The energy from two separate sweeps (seconds apart) is not combined (summed) in A/A radars. (Though many Surface Search radars do this. The technique is called "scan to scan integration")

 

--- Back ground ---

Some Pilots are told that they can detect targets at longer ranges if they use a smaller scan. The reasoning usually given is 'more energy on target'. 

While the outcome of this statement is true, the reasoning is not. 

As I stated previously, the 'increased detection range' is due to radar getting many more 'looks' at a target. 

You know how difficult and seemly weird it can be to get a good cellular signal connection when ur far from the tower. And how sometimes, for example, moving 1 foot to the right boosts your connection by 2 bars? What's happening is that the signal is bouncing all over the place (multipath), creating a complex web of standing waves. Now imagine both you and the tower are flying at 300 knots. bringing it back to the radar example, the pulse of light (RF is just lower freq of visible and infrared light) reflects off multiple point of the target. At some angles, the reflections will met each other again out of phase. Creating an RCS null. However, some moments later, as the geometries shift, the reflections may met together in phase, allowing for a strong radar return. 

 

--- When do pulses get to integrate ---

Separate radar pulse do integrate in AA radar. Just not on the time scale of separate sweeps (at least in AA radar). Typical pulse integration occurs within the time it takes a single beam-width of the radar to cross a point target out in space. (this value is known as time on target or TOT, and is on the order of tens of milliseconds) 

If one were to integrate pulses/energy of a longer period, they'd inadvertently increase their beam width and dramatically reduce their angular resolution. 

 

--- Scan to Scan integration with surface search radars ---

This technique is applied to a circular spinning naval radar with a fast scan speed. Pulses down a single bearing are saved and added to pulses down the same bearing on the next sweep. This is distinctly different from "pulse to pulse integration". 

 

The benefit surface search radars have in doing this has to do with ocean waves. If a radar does normal pulse to pulse integration, a given ocean wave wont move far enough between pulses to cancel out in phase (the wave doesnt move very far in ~10 msec). It thus adds constructively in the receiver.

However, when using scan to scan integration, the wave has enough speed to move in and out of phase between sweeps of the radar (order of .5 - 3 sec) which allows for some deconstructive interference to occur with ocean wave returns. 

Thus, it helps reduce noise from the ocean, allowing a clearer display of boats and land. Though it does reduce angular resolution.  

 

Edited August 27, 2022 by Beamscanner