Into Unscientific

Mentioned long ago.

There are more than 1,700 academicians of the two academies in China, covering a wide range of fields.

Therefore, even an industry practitioner like Xu Yun couldn't fully recognize the appearance of every academician.

Like the pick-up scene of the dark matter press conference.

Even with Xu Yun and Lu Chaoyang together, there are many academicians who cannot recognize their identities.

But on the other hand.

These "unrecognizable" academicians are basically relatively young new academicians.

For example, in 2023, they will still be in their fifties and sixties.

Xu Yun can still recognize most of the bosses who are over eighty years old and whose professional title is defined as "senior academician".

After all, the reputation of such academicians is basically not low.

If the age is pushed forward, it will be reduced to the first few batches of academic committee members in Huaxia.

Then their identities will be more recognizable.

Like this very moment.

Even though some bigwigs were still young in appearance, Xu Yun still recognized their true identities.

For example, the man standing by a tent not far away was flipping through a report or list.

This person has a face with Chinese characters, the corners of his mouth are slightly pursed unconsciously, his eyes are small but the black pupils account for a large proportion.

It is impressively the academician Sun Junren who is well-known in later generations.

He is a well-known electronic information expert in China. Academician Sun Junren personally established the Department of Radar Engineering of PLA Communication College.

There is also a man standing not far from Sun Junren.

This person was probably in his early thirties, with regular features, a straight nose, and an extremely handsome face, reminiscent of Planck's youthful demeanor.

He is Academician Baozheng, and his reputation in later generations is even greater than Academician Sun Junren.

Bao Zheng is known as the "Chief Referee" in China's radar industry, the pride of Xidian's radar department, and the old principal of Xidian.

The line of Baozheng in later generations is very important in the Chinese radar world, and many radars in China are produced by this line.

In the case of "poor and white" in the domestic radar profession.

He has participated in the teaching or tutoring of almost all the courses of the radar major, and dabbled in new knowledge such as information theory and network theory.

Compiled textbooks such as "Radar Indicating Equipment" and "Pulse Technology".

The first domestic microwave weather radar was also produced by Bao Zheng.

In addition, he also invented the "impact flashover method" for fault detection of buried power cables, which solved a major problem in the power supply department.

Of course.

Bao Zheng is still relatively young these days, far from reaching his future heights.

So at this moment, Baozheng was just standing beside a little old man with a bald forehead, a big nose, and extremely obvious nasolabial folds.

It's a coincidence.

Xu Yun also happened to know this person.

Because the other party is the first batch of academicians of the Chinese Academy of Engineering, Mr. Luo Peilin, the main founder of Xidian's electronic information engineering major.

Mr. Luo Peilin also directed the development of my country's first ultra-long-range radar and the first-generation series of computers. He belongs to the truly respected seniors.

In addition, Xu Yun also met Bi Dexian, Xiao Guozhen and other talented people.

Some of them are now members of the academic department—that is, later academicians.

Some are still the youth version of the boss, waiting for the version update or Longchang Enlightenment.

In addition, there are some experts that Xu Yun doesn't know but look very good. Most of them are masters whose names Xu Yun has heard but can't match their identities. His appearance has changed a lot.

When Xu Yun and others arrived at the watchtower.

Most of these bigwigs are concentrating on their work.

Some are measuring various data.

Some are calibrating and moving instruments.

Others were digging foundations with hoes — as I said earlier, watchtowers aren’t perfect radar placements.

In addition, there were a lot of staff coming and going at this time, so the appearance of Lao Guo and others did not attract much attention.

Even if someone noticed the figures of Lao Guo and the others, they just glanced away and looked away.

Lao Guo didn't exchange greetings with too many people, and led Qiao Caihong and Xu Yun straight to where Sun Junren was.

This area is located on the shady side of the watchtower, about a hundred square meters open, with several sky-blue tents set up.

There are some supplies and a few tables in the tent, which looks like a temporary command point.

When he was seven or eight meters away from the tent, Lao Guo waved his arms at Sun Junren.

"Hey, grandson! Long time no see!"

Sun Junren was looking at the material allocation list at this time, when he heard someone calling, he subconsciously raised his head and followed the voice.

Seeing that it was Lao Guo, Sun Junren took a long breath visible to the naked eye, and his eyes showed a strong look of joy.

He quickly put the deployment list on the table, and walked over quickly:

"Hey, Old Guo! You've really popped up. When I arrived at the base, I couldn't see you for a long time. I thought you were going to run away!"

Say it.

Sun Junren clenched his fist with his right hand and lightly thumped Lao Guo's shoulder.

Sun Junren and Lao Guo visited Mao Xiong together with the rabbits' industrial delegation four years ago and stayed in Mao Xiong for several months.

Although one of the two teams is negotiating the radar business, and the other is negotiating nuclear weapons matters, it seems that there is no intersection.

But very coincidentally.

During Mao Xiong, the two of them happened to be arranged in the same dormitory, or a double room, and they could see each other every day when they lowered their heads and looked up.

Over time, it will naturally become familiar.

At that time, Mao Xiong's policy towards the delegation was somewhat similar to the subsidy for overseas students in later generations. Each delegation member would receive a ruble subsidy for their daily expenses.

The specific amount is 30 old rubles per person per month-at that time, Mao Xiong hadn't carried out the third currency reform after the war, and 30 rubles was about 7.5 US dollars.

This part of the subsidy is provided by Mao Xiong, so there is a voluntary redemption plan inside the rabbit that is in short supply of foreign exchange:

Each delegation member can exchange this old ruble for Huaxia currency, and the purchase price is 1.5 times higher than the normal exchange rate.

So at that time, many members would save up their subsidies in order to exchange some more money with China and spend it when they return home.

After all, Mao Xiong provides three meals a day and accommodation, and everyone usually doesn't spend much money.

Of course.

There are also some people who did not choose to exchange.

The idea of ​​these members is basically that they want to buy some things from Mao Xiong that are not available in China and bring them back to China. After all, the living standards at home and abroad are quite different these days.

Lao Guo is one of them.

However, what Lao Guo wants to buy is not a luxury, but chlorpropamide-Lao Guo's wife Li Pei suffers from severe diabetes.

Chlorpropamide was the first generation of oral hypoglycemic drug invented in 1955. It worked well after it came out, but it could only be purchased abroad at that time.

As a result, Lao Guo had saved the subsidy for three months. Before leaving, he found that there was still 20 old rubles short, so he, Sun Junren and Zhu Guangya each borrowed 10 old rubles to buy medicine.

After returning home.

Lao Guo quickly returned Zhu Guangya's part of the money, but Sun Junren's money was delayed because he could not be contacted, and he couldn't even send a letter.

This is the first time the two have seen each other in more than four years.

Facing Sun Junren who came aggressively to "collect debts", Lao Guo punched him back with a smile:

"How can I run away? Do I, Guo Youlai, look like that kind of person?"

"Isn't it because I have never had a chance to see you? I have always written this down in my notebook. I will never forget it, never forget it."

Say it.

Lao Guo carefully took out a stack of square envelopes from his body, and handed it to Sun Junren:

"Here, the money is here. I know you are coming today and prepared it specially."

"Speaking of which, at the beginning you didn't care that I asked for the IOU, so could I actually not pay you back the money? Aha?"

The speaker has no intention, but the listener has the heart.

Hearing what Lao Guo said.

Xu Yun's originally relaxed heart suddenly sank slightly.

He remembers it well.

There is also a small book in the thermonuclear data that Lao Guo and guard Mou Fangdong tried their best to protect, which recorded many things to be done by Lao Guo.

In the middle of the second page of the book, there is a passage:

[January 3, 1958, Moscow, owed Comrade Sun Junren 10 rubles, equivalent to 4 yuan and 30 cents of the Chinese currency, not yet repaid]

Follow normal conditions.

Lao Guo had the opportunity to meet Sun Junren in two months.

However, due to the plane crash, Lao Guo forever lost the opportunity to repay the money by himself.

But now under the influence of Xu Yun.

Sun Junren, who never came to Factory 221 in history, appeared here today, and Lao Guo finally settled his worries.

Perhaps this is the meaning of crossing over.

Look at the envelope in Lao Guo's hand.

Sun Junren also restrained his smile instantly.

Then he took the envelope slowly, stuffed it into his pocket without looking at it, and sighed:

"Old Guo, you have a heart."

"Hey, paying off debts is a matter of course."

Old Guo smiled and waved his hands, shaking his head and said:

"It's not intentional, just don't blame me for procrastinating until now."

Sun Junren patted Lao Guo on the shoulder upon hearing this, and did not speak any more.

It may be difficult for future generations to imagine why the two academician-level bigwigs met in four years. No, counting the time of Lao Guo's sacrifice, it should be that there was no chance to meet or even send money for a full 10 years.

But in this day and age, this is actually a very common thing.

Some people hide their names and may not see people once in ten years.

Some people are running around, their whereabouts are uncertain, and their families don't know when they will return.

There are also some people who are busy with business, and forget many things while doing it, and may not be able to do it when they think about it.

Lao Guo's time is not the longest.

There is a big man named Wang Ganchang in the base, whose pseudonym is Wang Jing for 28 years.

28 years later, on July 3, he received a harmonica he bought 28 years ago

One generation has suffered the hardships of three generations. This sentence is really not touching myself.

After a while.

Sun Junren took a deep breath and dispelled the emotion to the back of his head.

He turned around to look at Xu Yun, and looked him up and down:

"Old Guo, this is the Qifen who came up with the weather Doppler radar plan. Cough cough, Comrade Han Li?"

Lao Guo nodded, turned around at the same time, and introduced to Xu Yun:

"Xiao Han, let me introduce you. This is an old friend of mine. Comrade Sun Junren is currently a seventh-level worker at the Jinling Radar Factory."

Xu Yun glanced at this 'teacher', and smiled as if he didn't know anything:

"Gong Sun, hello, I'm Han Li."

Sun Junren gave Xu Yun a deep look.

Don't look at the fact that Liu Bosheng and the chief already know the accuracy of the weather Doppler radar principle.

But in fact, only professionals like Sun Junren understand how terrifying that principle is.

It can be said like this.

Judging from the current information that Sun Junren and the others have.

The research and development progress of the Doppler radar on the other side of the sea is at most only 10%-15% of this plan!

This is a very subversive figure.

Even if Xu Yun is only a transmitter of related theories rather than a builder, he is still extremely extraordinary.

More critically.

Sun Junren was by his side when the chief spoke with Liu Bosheng, and he knew very well the chief's attitude towards this young man:

Respect, protect.

And if there is a chance, I hope to meet up or chat on the phone.

That's the chief

Speak the truth.

Sun Junren was even a little jealous of Xu Yun.

However, Sun Junren also knew that they had business to deal with at this time, so they quickly suppressed this emotion.

He looked around, pointed at the tent and said to Lao Guo and Xu Yun:

"Old Guo, Comrade Han Li, it's getting hot outside, let's go to the tent and talk."

Lao Guo and Xu Yun have no objection to this.

Then Sun Junren led the three of them to the side of the tent, picked up a small bowl from the table, and handed it to Lao Guo and the others:

"Come on, let's eat some watermelon, we brought it here from the capital."

The bowl in Sun Junren's hand was about ten centimeters in diameter, similar to the soup bowls in later noodle shops, and contained some watermelons cut into pieces.

Each piece of watermelon is cut very "delicately", and the size is only about the size of the sugar cubes that are commonly used to make coffee in later generations.

Some watermelons are also inserted with a bamboo stick, so that everyone can eat them conveniently.

Seeing this, Lao Guo took the initiative to pick up a watermelon with a bamboo stick, put it in his mouth, chewed it a few times, and spit out two watermelon seeds after a while:

"It's so sweet!"

"It's delicious, right? We grow it ourselves in our yard."

Sun Junren smiled at him, then turned the small bowl to Qiao Caihong and Xu Yun:

"Come on, Comrade Nurse, Comrade Han Li, you two should try it too. It's not easy to eat such fresh watermelons in Xihai."

Qiao Caihong glanced at Lao Guo, and after getting his permission, he generously picked up a bamboo stick and handed it to Xu Yun:

"Comrade Han Li, open your mouth."

Xu Yun was basically 'fed' by Qiao Caihong these days, so he didn't feel embarrassed on this occasion, so he obediently opened his mouth:

"ah"

Qiao Caihong took advantage of the opportunity and put the watermelon into Xu Yun's mouth.

The bright red flesh of the melon has a special fragrance, and the juice fills the gap between the teeth after one bite, and slowly flows down the throat, immediately refreshing the whole body.

Sun Junren held his hands behind his back, and waited until Xu Yun had eaten several mouthfuls before saying:

"Comrade Han Li, how does it taste?"

Xu Yun licked the corner of his mouth:

"Very sweet and moist."

"That's good."

Sun Junren glanced at him with a smile, and said like an old fox:

"By the way, Comrade Han Li, I almost forgot to mention it."

"Our watermelons are limited, and transportation is not easy. Each person can only eat three small pieces of fruit after working for half a day."

"Now that you've eaten one, three, five, oh, six pieces of watermelon, shouldn't it be time for you to contribute?"

Xu Yun was startled:

"?!"

I # , boss, do you want to do this routine?

Then Xu Yun glanced at Lao Guo who said "I don't know anything", and sighed resignedly:

"Okay, Sun Gong, if there is anything I can help you just say it."

Sun Junren was waiting for his words. Hearing this, he immediately took out a stack of calculation papers and stacked them in front of Xu Yun:

"Here, these are all."

The corner of Xu Yun's mouth twitched again:

"."

But when you think about it, it's normal.

After all, this year is different from later generations.

Today's radar industry is still in a very primitive stage.

Except for those military industry leaders involved in the development of Doppler radar across the sea, most experts basically know nothing about the principle of Doppler radar.

Even though Xu Yun gave a very detailed explanation in the telegram, some steps are still difficult to understand.

"The first is Doppler processing at the echo signal."

After Xu Yun agreed.

Sun Junren quickly picked up a pen and paper, and drew a circle on the first question:

"Comrade Han Li, you defined it as Range Doppler Map in the telegram, that is, range Doppler processing."

"According to your description, this should be a step that is processed in the distance dimension and velocity dimension, right?"

Xu Yun nodded:

"That's right."

Seeing this, Sun Junren snapped his fingers:

"Then here comes the question, Comrade Han Li, in this step, can't we directly perform Fourier transform on the slow time dimension?"

"Why do you require the time-distance image first, and then do the Fourier transform on the slow time? Isn't there Doppler information in the phase information in the original matrix?"

When Xu Yun heard this, he couldn't help raising his brows.

Good guy.

As expected of a top leader in radar, he asked such a core question as soon as he came up.

Sun Junren's problem can be described in the terms of later generations, which can be shortened into another very simple sentence:

Why is the velocity-dimensional FFT based on the distance-dimensional FFT instead of directly using the time-domain waveform matrix to directly perform slow-time-dimensional FFT to obtain velocity information?

The FFT in it refers to the fast Fourier transform, but the concept of this point in time has not yet been proposed-because it is an algorithm given to the computer.

This sentence can be said to be a very critical difficulty in the principle of Doppler radar. Many people in later generations will fall into this pit.

Then Xu Yun thought about it and explained:

"Sun Gong, from a mathematical point of view, the distance-dimensional Fourier transform is performed first because of the need for speed calculation."

"Because the velocity estimate is calculated from the phase difference between adjacent pulses, our radar's own position is always constant."

"That is, after the range-dimensional Fourier transform, the peak value of the frequency spectrum corresponding to the target distance does not change."

"That is, what changes is the phase of the frequency point between multiple pulses, and this change is the same as the phase change in the time-domain signal."

Say it.

Xu Yun wrote a derivation process on paper with barely moving hands:

If there are peak amplitudes without targets that are much smaller than peak amplitudes with targets:

abs=\\sqrt{(A^2+B^2)}\\ll abs'

Then there are: AA′, BB′A\\ll A', B\\ll B'

Therefore, there exists:

Z=A+i B，heta=\\arctan (B / A)\\ll\\arctan (B'/ A')

At the same time ds2=c2dt2+a2(t)dr2=0

Can get c∫t1t0dta(t)=∫0r1dr

c∫t1+δt1t0+δt0dta(t)=∫0r1dr

well known.

The purpose of doing FFT in the distance dimension is to find out the relationship between distance and frequency, without any change in the phase of the distance.

Therefore, the velocity dimension FFT is based on the distance dimension FFT, and only extracts the phase change of the distance position.

If the second speed-dimension FFT is not based on the result of the distance-dimension FFT, of course the speed of the target can also be obtained.

but

This speed cannot distinguish between the speed of a single target and the speed of multiple targets.

That is to say, the speed is only kept as a straight line, and it cannot distinguish whether there are two targets with the same speed and different distances-this sentence is very important, and I will test it later in a few chapters.

Of course.

Later generations of computers have a clearer answer to this question.

Because the computer can use Python to make a more intuitive picture, which is easy to understand.

However, Xu Yun's explanation is quite thorough, at least for people in the industry like Sun Junren.

"So it is"

Sun Junren touched his chin, hesitated for a moment, and guessed:

"Since it cannot be converted directly, it means that after the radar is activated, there should be a signal with zero frequency but high energy?"

Xu Yun stopped talking:

"?!"

This moment.

Suddenly there was an urge to flip the table in my heart.

I # , have a hang!

Nowadays, the meteorological Doppler radar is only a spare part. Sun Junren has realized the important situation that the Doppler radar will not be discovered until the eighth year after it is in operation?

Students who have made radar spectrum charts should know it.

After the FFT of the distance dimension is done, and then the spectrum of the FFT of the velocity dimension is done, it will be found that a very high energy peak will appear at the position where the distance gate number of the zero-velocity channel is equal to 0.

The frequency of this signal is zero, so it is also called a DC component - the so-called DC means that it has only magnitude and no direction.

Sometimes this DC component is relatively small.

Sometimes it will be larger.

When it is large, it can reach the order of 10^5.

When I was young, it was on the order of 10^3.

In principle.

There are many reasons why the DC component occurs.

For example, the transceiver isolation is not good enough, and it cannot be balanced under noise conditions.

So these reasons are actually not the point, the real point is

Before the appearance of Doppler radar, the concept of DC component did not exist in the spectral frequency-because the radar field has not yet used the double-angle formula to process signals.

more importantly.

If you notice the DC component and try to block the DC, the rabbits are likely to discover another new world in advance!

That is.

Hysteresis Control Inverter!

That's right.

The opportunity for the emergence of the hysteresis control inverter is the DC component of Doppler radar.

It took another seven years for the concept of DC component to be discovered in Spectrum Frequency, and then the opposite side of the sea began to consider DC isolation, and another two years later, the hysteresis control inverter was invented.

You may not be familiar with this stuff, but one of its key applications must be familiar to everyone:

It is a vital application of stepper exposure pool and microprocessor.

The reason why Philips was able to overcome the technical blockade was that it invented the step-scan lithography technology.

One of the important breakthroughs is the hysteresis control inverter.

And that was already in the late 1990s.

Indeed.

The span from the DC component to the hysteresis control inverter is very large, and the hysteresis control inverter to the lithography machine is even farther apart.

In a sense.

This is equivalent to the difficulty of developing from the phrase "the 21st century is the century of biology" to a 3 million-word novel, and there are too many coincidences in the whole process.

but the problem is

In this dungeon, there is Xu Yun, a tentacle monster that changes 30,000 times a day!

As long as he gives a little guidance, this is a set of procedures that can evolve smoothly.

After all, due to the existence of the 404 Great God, Xu Yun was unable to change certain general trends.

But this act of kicking history's ass twice can still be tried.

For example.

Let the rabbits have the ability to produce 1 micron chips in the 1980s?

hiss.

This picture is so beautiful.

Then Xu Yun wiped the non-existent saliva from the corner of his mouth, and pulled his mind back to reality.

Although the picture is beautiful, the more critical thing right now is to deal with the assembly of the weather Doppler radar.

So he coughed lightly, raised his eyelids to look at Sun Junren, and explained:

"That's right, Sun Gong. According to theoretical deduction, such a special signal should indeed appear on the Doppler radar."

"And according to the speculations of other seniors in the Fenglingyueying Society, if it is not a periodic signal, then the process of taking the limit should be omitted when expressed in a mathematical formula, and the integral limit can take any period."

"Of course, these are only theoretical calculations. It may be possible that this signal will not appear at all by then."

I heard this.

Sun Junren nodded slightly.

The current period is at the peak of the development of physical phenomena, and mathematical theories are often questioned because they cannot explain phenomena, so the situation Xu Yun said is entirely possible.

Besides, Sun Junren has not realized the possible impact of the DC component, at most he just feels that this is a special situation.

So soon.

Sun Junren turned his attention to the second question, and at the same time pointed to Baozheng at the side:

"Then let's talk about the next question, Comrade Han Li, this is a question raised by my assistant, Comrade Bao Zheng."

Then Sun Junren turned a page of the manuscript and said aloud:

"Comrade Han Li, according to the theory you put forward, the weather Doppler radar uses the idea of ​​clutter suppression in the filtering part, and the process is indeed very delicate."

"However, according to Comrade Bao Zheng's calculation results, this suppression process seems to be somewhat weak. At least a Doppler filter with a zero notch is definitely unable to suppress rain clutter and ground clutter."

"For example, in the range of 2-5 pulses, we should be able to handle it normally."

"But if the input to the filter is 8-10 pulses, it's almost impossible to shape them like you're talking about."

"So if the weather Doppler radar is going to take on a wider range of data collection tasks, then this problem has to be solved."

I heard this.

Xu Yun couldn't help but look at the very handsome Bao Zheng standing beside Sun Junren.

Good guy.

The big guy really didn't let himself down.

The two questions raised by him and Sun Junren are basically the two most critical theoretical issues outside the implementation process of the early meteorological Doppler radar.

And is different from the DC component.

Baozheng's problem is not a minor problem, but will directly affect the efficiency of weather Doppler radar.

Another point is

Sun Junren's prediction of the DC component was not in Xu Yun's plan, it was an accident that even Xu Yun didn't expect.

However, the filtering problem raised by Academician Baozheng was deliberately laid by Xu Yun, a fisherman.

mentioned earlier.

The filter design scheme given by Xu Yun before is a relatively simple 2-pulse MTI canceller, which is relatively cheap to manufacture.

This thing has a very special place, that is, it is very narrow in Doppler space.

It is so narrow that it can only hold two pulses at a time. If the pulses are thicker, there is at most one more, and any more will expand.

As for the solution to it

Think here.

Xu Yun couldn't help showing a bit of embarrassment on his face, shaking his head and saying:

"Sun Gong, to tell you the truth, it may be very difficult to solve this problem, and it cannot be solved by a small factory of yours."

Sun Junren raised his head and glanced at him, with such an expression on his face:

"Indeed, but it doesn't matter, Comrade Han Li, you can just talk about it casually."

"Even if it can't solve the problem, at least it can solve the confusion for Xiaobao and me, don't you think so?"

Bao Zheng on the side also nodded purely.

Xu Yun:

"."

These bosses seem to have unexpectedly thick skins.

But that's fine too.

Since you guys are so thick-skinned, don't blame me for pretending to be stupid too.

Anyway, regarding Biao's acting skills, he has passed the test of Maverick Lao Su Xiaomai's three dungeons, and he has never been afraid of anyone.

So Xu Yun quickly showed a hint of approval:

"In that case, Sun Gong, let me just talk about it casually."

"The way to implement a strong filter bank is actually very simple, that is, to use the discrete Fourier transform."

"That is to use the Doppler filter bank and the combination of 2 PRFs to establish the ambiguity function to solve this problem."

"Fuzzy function and PRF?"

Sun Junren blinked, quickly picked up a pen and calculated:

"Oh, you mean to introduce multiple beams, and then use the matrix to construct the response function, and perform efficient calculation in the frequency domain of the augmented region."

"Well, that's a very innovative idea."

"L selects a positive integer greater than 2N1's smallest 2 to the power of m, that is, L=2ceil(log2(2N1)), and then constructs a y sequence of L points y=gL(Wn2/2⊙x)"

"W=exp(j2παN), n=[N/2, ., N/21], ⊙ represents dot multiplication operation"

The result is written.

Sun Junren paused suddenly, and his breathing stopped for a moment.

After a few seconds.

Sun Junren folded the piece of calculation paper calmly and put it aside, raised his head and said to Xu Yun with a 'casual' smile:

"I see. But Comrade Han Li, this kind of calculation process should be more difficult, right? It seems that the amount of calculation is huge?"

Xu Yun still nodded with a cute face:

"Yes, this step needs to be processed digitally with computer software, so I said that it cannot be done by a small factory of yours."

Say it.

Xu Yun quickly pretended to cough lightly to cover up the corners of his mouth that were about to turn up higher than the Dragon King.

no doubt.

Sun Junren's actions just now were definitely hooked!

After all, the idea proposed by Xu Yun is not difficult in theory, but no one has ever thought of this level.

That is.

The Chirp-z transformation is changed through the fuzzy function, and the Doppler distance is converted into a convolution form.

And to this point.

Sun Junren will find that the data he calculated has been converted into variants of the other two parameters:

Ground speed and drift angle.

And these two parameters are necessary data for fighter radar!

The two rabbits started research in this area ten years ago, but there is still no actual output data!

Of course.

Fighter radar is not Xu Yun's ultimate goal.

After all, the radar early warning technology of fighter jets in later generations is very complicated, and the gap between domestic fighter jet radars and those across the sea is actually not that big.

Some people think it's over.

Some believe there is still a gap.

But no matter what kind of views people hold, they will not think that there is a concept of "generation" in this gap.

Oh, except for the military announcement that the aircraft carrier can be photographed as a small fishing boat.

So Xu Yun's real target is not the radar.

but

What is needed to develop the radar.

That is——

Domestic industrial software!

Note:

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