Fortunately, for Guo Lin, he is used to this situation.

What's more, according to Chang Haonan, it is not a loss to be able to publish a good journal.

At least it can be used in the future when evaluating senior titles.

"I need some time."

Chang Haonan had already formed a general context of this idea in his mind, but the more he dug deeper, the more he realized the complexity of this thing, which was definitely not something he could calculate on the spot in this conference room with a piece of paper and a pen:

"Researcher Xu, do me a favor, it might be a bit complicated this time."

"No problem, what do you need me to do?"

Xu Yang stood up and followed Chang Haonan to the nearby computer room.

"Improving some algorithms, of course, is just some of my ideas......"

Only Guo Lin and the others were left looking at each other.

Guo Gong...... Let's ...... next."

Another colleague who was quite confident with Guo Lin was also a little confused by this sudden change in the situation.

"Alas...... Let's sort out this set of things first, according to the opinions of Chang Gong, IEEE Transactions on Aerospace and Electronic Systems is also a small top journal......"

Yan Liang received the new components from the 14th Institute the next day, but the modification of the No. 2 pod was requested by Chang Haonan to be put on hold for the time being.

He has systematically confirmed the feasibility of this new theory, and the next step is just to implement the algorithm model step by step.

Once completed, it can greatly improve the performance of the planned J-7 electronic warfare aircraft.

It is even possible to rely on this technology to directly track targets outside the normal radar detection range!

……

Four days passed quickly.

Chang Haonan and Xu Yang regrouped the people from the 14 institutes in that research room.

"You should have all read the paper on volumetric Kalman filtering that I posted with Researcher Xu?"

Chang Haonan skillfully took the new pen and paper from Guo Lin's hand and asked the surrounding engineers.

Everyone nodded:

"Of course I did."

"Theoretically, by applying the CKF algorithm to the nonlinear observation equation, the radar registration bias correction and target state prediction can be realized, combined with the maximum likelihood estimation, and even the target data can be processed in batches ......"

Chang Haonan first briefly introduced the situation in an ideal state, which is not difficult for everyone to understand.

"But in practical applications, we will definitely have some signal misses, and there will be a lot of clutter in the area, and the CKF algorithm will not be so easy to use."

"So in the face of this reality, instead of blindly trying to avoid these irrelevant third-party clutter, we should find ways to use them to enhance the passive detection of targets."

"Utilizing third-party clutter?"

Another engineer behind Chang Haonan lit up:

"I have a younger brother who served in the submarine force, and I heard him say that in the Cold War, the nuclear submarines of the East and the West had a tactic, that is, to lay a mine at a known location, and then detonate it at a specific time, and use the sound waves generated by the explosion of the mine to carry out an active sonar detection of the target in the entire area without exposing itself, and the effect is much better than pure passive sonar."

Someone can draw an analogy to his thinking in this way, which surprises the former:

"That's right, the mine you are talking about is our third-party signal source, it can be a civilian weather radar, a signal tower, or even a radar wave emitted by other friendly or enemy forces in the area, but the stronger and more regular the signal, the better the effect."

"Of course, researcher Xu and I also combined the sequence difference histogram method to further improve the PRI algorithm mentioned by Guo Gong.

"However, the speed of naval warfare is calculated in minutes, while the speed of our electronic warfare is calculated in microseconds, and the target often has a speed of hundreds or thousands of kilometers per hour, so there are fundamentally different requirements for our data processing accuracy and speed."

"So I'm going to call the set of things I'm going to talk about here as Stochastic Finite Set Theory (RFS)......"

Chang Haonan said and took out the calculation process of almost the thickness of a book from under the table.

“woc……”

Guo Lin was so shocked by this scene that he almost burst out.

"First of all, let's define what a random finite set is."

This time, everything he was going to talk about had already been printed out on paper, so he didn't have to write and draw:

For a locally compact Hausdorff divisible space E, the set of all finite subsets in it is denoted as (E). THEN, A RANDOM FINITE SET Ξ ON E CAN BE DEFINED AS A MEASURABLE MAP Ξ:Ω→(E)......"

"FOR AN RFSΞ, THE NUMBER OF ELEMENTS IS EXPRESSED AS |Ξ|, I.E., THE POTENTIAL OF THE RFS. In addition, the elements in RFS are disordered, i.e., the sufficient and necessary conditions for RFSΞ to be the same as RFSΞ′ are: (1)|Ξ|=|Ξ′|, (2) if the element ∈Ξ, then ∈Ξ′"

“……”

“……”

"In short, if we design a radar, of course, including post-processing software, and implement this model in engineering, we can passively detect the target without actively emitting radar waves, and we can achieve effective monitoring and tracking."

When Guo Lin handed Chang Haonan the brewed tea for the eighth time, the theoretical explanation, which lasted for more than four hours, finally ended.

"Any more questions?"

Quiescence.

The only sound in the room is the hum of fluorescent tubes being electrified.

Chang Haonan took a sip of water.

He knew he needed to set aside some time for everyone to think.

After all, even Xu Yang, even if he was cheating in the system, he had to go around for a while before he fully understood all this.

"Uh......"

The first to speak was Guo Lin:

"Isn't that invincible when you think about it? As long as our radar backend has enough computing power, then even stealth targets can't escape? ”

"And this should not only be an electronic warfare method, but all targets can be detected in this way."

The other replied with a look of astonishment.

"Theoretically, of course."

Chang Haonan put down the water cup and nodded:

"But as you just said, you need to have enough computing power first, which is actually certainly not that good, and because the third-party irradiation source or target radiation source is not controlled, the passive radar cannot guarantee continuous operation, or it needs a self-sacrificing unit to be the radar irradiation source, such as a large drone or something......"

"In short, judging from our current actual situation, it is best to combine passive positioning technology to play a role in countering the opponent's SEAD operations."

"Also effective against ground-based radars?"

It stands to reason that this kind of technology of relying on radar to detect targets should be mainly used for air defense.

"No, no, no, you didn't understand what I meant."

Chang Haonan shook the pen in his hand:

"It's not a SEAD operation, it's an anti-SEAD operation."

"When they want to hunt our radar, even if our ground-based radar is jammed, the radar waves emitted can still be regarded as an effective third-party radiation source for effective detection of the opponent's electronic warfare aircraft."

"The praying mantis catches the cicada, and the yellow finch follows."

"It just so happens that the J-7 in Factory 172 has entered the end of the transformation, and if we move faster, we can actually verify this tactic on it."

"So...... We have also developed a countermeasure algorithm for electronic warfare? ”

Guo Lin never expected that the countermeasures that they had been pursuing for several years in 14 institutes would be achieved through this method-

You can interfere with me, but I can also just throw your whole family up.

Today, it's time to celebrate Double 11

(End of chapter)