Chapter 387: Let’s Make a Big Change
Gao Zhendong thought about giving the final plan directly, which would be simpler and more direct, but the comrades in the Institute couldn’t stand it.
You know there are several other ways, but Gao Zhendong jumps over you. How can you bear this?
Even if you can't use this bomb, you can use stones from other mountains to attack jade and open up new ideas. No matter how backward the technical solution is, you can listen to it. Maybe you can use it for something else at some time. place.
Not to mention that the essence of many solutions is not in the specific technology, but in the ideas and solutions to the problems.
Besides, Consultant Gao’s plan shouldn’t fall behind, right?
The chief model engineer of the Guidance Research Institute couldn't help it: "No, Consultant Gao, tell me about the other ones too, don't jump over, we all want to hear it."
Others in the Guidance Research Institute, especially Lu Gong who was engaged in guidance, nodded quickly, yes, yes, yes.
The two members of the National Defense Working Committee couldn't hold it back and burst out laughing.
These people are so interesting.
Gao Zhendong had no choice but to introduce the other types and explain the flaws one by one.
Conical scanning can also be called FM modulation. This thing is better than AM modulation. The plate does not rotate, but the sub-reflector rotates. The mirror rotates and the signal is reflected to the sensor through the modulation plate. When the seeker is facing the target, the output signal is uniform. Once it deviates, the signal width and frequency will change to guide the missile.
But the biggest problem with this thing is that its ability to resist background interference is worse than AM!
The four-quadrant detection seeker divides the sensor into four pieces. The difference in signal strength on the four sensors indicates the target direction. It looks a bit like a four-element orthogonal detection seeker. In fact, They are two different things. The former is controlled by signal amplitude, while the latter is controlled by signal frequency. If I must say it, the quaternary quadrature and FM modulation plates are more closely related.
This thing has the same problem as cone scanning.
Rose line scanning uses a small field of view sensor to scan the entire detection area. It is a guidance technology of the same generation as orthogonal quaternion. In terms of effect, it is better than orthogonal quaternion. It can even perform sub-imaging, which is worse than focal plane array. , but stronger than others.
But the biggest problem with this thing is that the system is complex, the requirements are high and the cost is high. Although it is lower than the focal plane, it is more expensive than other principles.
The primary mirror of the entire system must rotate forward, the secondary mirror must rotate reversely, and there is a decentering mirror behind it. Not to mention the mechanical system, the optical system is troublesome enough, and the requirements for scanning stability are quite high. , for this era, it is a bit excessive, and there is also an interception probability issue. If the speed is slow, the probability is low, and if the speed is fast, the system requirements are high.
But the comrades from the Institute of Guidance and Research don’t care about this. Let’s write it down first. Different methods can be used for ammunition with different requirements.
Although this was very simple, it took almost half an hour before Gao Zhendong finally got to the point, four-element orthogonal scanning.
This seeker head structure is actually similar to the cone scanning head, but the modulation plate is removed, and the sensor is replaced by four orthogonal strip sensors to form a cross, with each side of the cross being a sensor.
The output signal is a pulse signal, which looks similar to a cone scan. If you only control the direction of the missile, you can directly use the output pulse signal for control.
When Lu Gong heard this, he had questions: "Then what is the difference between this method and the previous one? Cone scanning cannot distinguish multiple light sources, how to distinguish this?"
Gao Zhendong laughed. : "The orthogonal quaternary mirror also rotates, but its rotation is that the primary mirror and the secondary mirror rotate together. The mechanical part is much simpler. There is no decentered mirror, and the optical system is also simple. As long as the rotation speed is constant, the requirements for scanning stability are not high. , combined with these, its comprehensive performance is the best at this stage.”
“As for distinguishing multiple light sources, this method can automatically generate a reference signal by using the rotation of the main mirror, and combine it with the scanning signal. Gain the ability to differentiate between multiple light sources ”
Even if a detector of this structure is interfered with by laser, as long as it is not directly burned through with high power, it is more difficult for continuous laser to interfere with it. You have to use pulsed laser, and you also have to consider the frequency, duty cycle, etc. of the interference source, which makes the interference party very uncomfortable.
Orthogonal four-element detection, a detection principle commonly used by third-generation anti-aircraft missiles. It also includes Lao Maozi's R-73, which is a missile famous for its off-axis launch angle. However, Lao Maozi uses an L-shaped binary array. The actual principle is similar. On this point, I really have to admire Lao Maozi. You can use seemingly ordinary basic skills to do all kinds of fancy things.
Comrades from the Institute of Guidance and Research followed Gao Zhendong’s thoughts and couldn’t help but marvel.
The beauty of this plan is that it is all structural adjustment, but it does not have excessive technical requirements. It removes the obstructive modulation dial and at the same time greatly improves the performance of the entire guidance system. performance and anti-interference ability.
It can be said that the technology that can make an amplitude modulation disk seeker can make an orthogonal four-element seeker.
Lu Gong shook his head: "Consultant Gao, your idea is really brilliant! The technology is not complicated, but it is very effective in solving problems. What is this called? By the way, it is too clever to work, and it is too clever to work. ”
Although the orthogonal four-element detection seeker only appeared in the era of indium antimonide seekers, this does not mean that it can only be used on indium antimonide seekers. In fact, it is just a technology The development time coincides with each other, and the two are completely different tracks.
The principle of this method can also be used in refrigeration lead sulfide. The two people from the National Defense Working Committee looked at Gao Zhendong with complex expressions on their faces, including satisfaction, surprise, solemnity, and joy.
The chief engineer of the air-to-air missile model thought for a while and asked a question: "What about this method? , what are the shortcomings? ”
Gao Zhendong also thought about it: "For the current stage, there are no shortcomings. If we have to say shortcomings, there are two."
Everyone cheered up and were very interested in the shortcomings.
“First, if you want to exert its anti-interference ability, the requirements for the guidance and control system are a bit high. It is best to have a certain amount of computing power, otherwise the multi-target resolution capability will not be very good.”
If you want to start from the reference signal and scanning signal and combine the calculation to distinguish multiple targets, the analog circuit is a bit difficult, or the cost is very high.
This is probably the reason why this technology has become so popular since the third generation of infrared air-to-air bombs. There was no computer in the front.
When everyone heard it, it turned out to be this. That’s okay. What is your DJS-60D for?
"Then you need to ask Consultant Gao to extend his hand and re-layout the boards of your DJS-60D."
Now the minimum unit length and width of DJS-60D are about 25cm. , it needs to be smaller. The diameter of the infrared air-to-air missile is only half of this number.
“What about the second flaw?” Lu Gong asked.
“In fact, the second flaw is not a flaw in the orthogonal four-element detection principle, but a flaw in the infrared sensor itself. The problem is that the sensitivity is still not high, so even if this method is used, the improvement of head-on attacks It’s still very limited, and it’s still not usable, but it’s okay to further improve the attack distance and success rate in the rear hemisphere.”
When the comrades from the Institute of Guidance and Research heard this, they felt half-hearted, but then they cheered up again. They were greedy, weren't they? When you can solve the anti-interference problem without any major technological changes, what more do you want?
Being able to improve the distance and success rate of the rear hemisphere is already a major improvement.
The Chief Engineer of the Defense Works Committee smiled and said: "This is not a big problem. Comrade Zhendong, there is nothing wrong with the technologies you have come up with. If there are any problems, they are all our own. The problem is, the sensor is not good enough. It is not worthy of the good method you gave us.”
These words made the comrades in the Institute feel a little feverish. Hey, it’s so embarrassing!
But when I think about it, weren’t we taught how to do lead sulfide refrigeration and rocket engines?
Forget it, get used to it, this is our technical consultant, one of our own, no shame.
Gao Zhendong sat there with a cheerful look on his face, which made the leader of the Defense Working Committee feel moved.
This boy, look at his expression, is there an ambush?
The leader looked at him and directly exposed his background: "Zhendong, looking at you, it seems that the sensor can do something about it?"
Hmm? After hearing the leader's words, everyone turned their attention to Gao Zhendong.
Yes, you can laugh like this even though you know there is a problem. No, there are circumstances.
Seeing everyone looking at him, Gao Zhendong was a little embarrassed: "Yes, yes, in fact, I think, the current Thunderbolt-1 does not need minor modifications, the cost is low, the performance is good, you can use it yourself It can be used to support others. What I just said, plus what I want to say next, is to change the missile body and spend more time to change the model. This will not disrupt scientific research and equipment. Rhythm. "
The missile body cannot be changed, otherwise the G value will not increase, and the seeker that I want to take out will be in vain. It will be better to at least change it to a level close to the third generation infrared air-to-air missile.
The seeker structure has been changed, the infrared sensor has been changed, the guidance computer has been changed, and the missile body structure has also been changed. It is not a major model change.
Everyone was excited when he directly mentioned a major change in model. This shows that he is very confident in what he is going to come up with! Otherwise this would not have been brought up.
"Wait, let's clear the area again!" The leader of the National Defense Working Committee told him to stop again. When he thought that the specific names and composition of the materials might be involved, it was better to be careful. Comrade Zhendong's place, anything could get out. jump.
This time there are only six people left, the leader of the National Defense Work Committee, the chief engineer, the model chief engineer of the Institute of Guidance and Research, Lu Engineer, Gao Zhendong, and a comrade from the Flying Army.
After the clearance was completed, the leader looked at Gao Zhendong.
“Say it quickly, as long as the product is good, I can give you a major overhaul or even a new model.” The leader of the National Defense Work Committee’s eyes lit up and he was very happy.
(End of this chapter)