Chapter 167 Frequency Controversy

  In the field of radar, frequency, or the wavelength of electromagnetic waves, is divided according to certain rules.

  When radar was first applied, it was only used for long-distance search. The antenna shelf of this radar was very large, similar to a TV antenna. The wavelength was in the meter band, which was called the P-band.

   (Past band, P is the first letter of Previous).

Later, with the continuous improvement of technology, the 23 cm band was selected as the electromagnetic wave of the search radar. This band was defined as the L band (long band, L, the initial letter of Long). Later, there were some changes. The central wavelength of this band became is 22 cm.

  Afterwards, a radar with a wavelength of 10 cm appeared. Compared with the previous L-band, this band is defined as the S-band (short-band, the initial letter of Short, which is an electromagnetic wave shorter than the wavelength of the L-band).

These bands are used for searching. The shorter the wavelength, the higher the accuracy of the radar. Therefore, in the later stage, after wanting to use the radar to accurately find the distance position of the target, a fire control with a wavelength of 3 cm electromagnetic waves appeared. For radar, this band is called the X band, and X represents a certain point on the coordinates.

The X-band radar has high precision, but it also has a disadvantage, that is, the shorter the wavelength, the closer the radar’s irradiation distance. Therefore, in order to combine the advantages of the X-band and S-band, a radar with a wavelength of 5 cm has appeared. This band is called the C-band (combined with the band, C is the first letter of Combined).

  At that time, in addition to the United Kingdom, the Germans also began to independently develop their own radars. Rigorous German engineers chose the 1.5 cm band, which is called the K band (K, the initial letter of Kurtz, meaning "short" in German).

  Unfortunately, the Germans have a problem with this wave band. This kind of electromagnetic wave is just strongly absorbed by water vapor. As a result, radar in this band cannot be used in rain and fog. In order to avoid this absorption peak, there are two improved bands, one is slightly higher than the K-band frequency (Ka, English K-above, above the K-band) and slightly shorter (Ku, English K-under) , below the K-band) band.

Because the naming method of these bands is too messy, a reclassification method was developed internationally later, and the order of electromagnetic waves and the order of English letters were compared and named. However, this most popular method is still used in China. Commonly used band naming methods.

  14 chose the S-band, which is a wavelength of ten centimeters, and Space System 23 chose the C-band, which is a wavelength of five centimeters. The latter has higher accuracy and can be used to directly illuminate the target. It can be used as a fire control radar, which can kill two birds with one stone.

  However, the latter band also has a biggest problem, because its wavelength is shorter, so its search distance will be much closer under the same radiation power.

  It is the same as the 14th Institute’s plan, that is, on a rectangular area of ​​four meters by four meters, if the C-band is used, then the search distance will not even reach 200 kilometers, which is only 150 to 60 kilometers!

After the collapse of the Red Empire, it is said that Lao Maozi has carried out a series of cooperation with China. The phased array radar transferred by Lao Maozi is called Sea Lion, which belongs to the C-band active phased array radar. The actual effective range is 150 kilometers. .

  Of course, based on Lao Maozi’s electronics industry level, this kind of active phased array radar may not be able to be manufactured, it is probably just a PPT product.

Although the number of active phased array radars required by the navy is not particularly large, it is still a huge order, and the experience gained in the navy's projects can also be used in the air force's fighter planes and ground air defense forces superior.

   So, it's a big cake.

  At this point, as the two sides put forward their respective plans, the heated debate began.

"The Aegis system of the United States uses the S-band, so their phased array system can only be used to find targets, and a special guidance radar is needed for target illumination. The actual firepower channel is limited by the target illumination radar. Quantity does not fully provide the ability to resist saturation strikes."

"That's right, the MK-99 fire control subsystem of the Aegis weapon system is controlled by four AN/UYK-20 computers, each of which controls an AN/SPG-62 target irradiation radar, and can deal with up to four targets at the same time. It is possible to allow the phased array radar to pre-guid, at most it can intercept 12 targets in a wave of attacks, and it cannot achieve the ability to resist saturation attacks at all."

   "If the C-band is used, the radar irradiation distance is only more than 100 kilometers, which cannot meet the needs of the navy at all. The hard target proposed by the navy is that the search distance is at least 200 kilometers."

"This distance can be changed. We have more than phased array radars on our warships. It consumes too much electricity. We must have a special sea search radar. Just install our meter wave sea search radar to realize it." With a search distance of three or four hundred kilometers, wouldn’t this problem be solved?”

  Countless people have commented, some people support 14 institutes, and some support a certain aerospace institute.

  For the navy, it is quite critical. After all, they do not have the ability to support two projects at the same time. If the route is chosen wrong, it means a huge waste.

  Wu Shengli turned his attention to Mr. Wu: "Now, let us ask our experts in the development of relevant types of missiles to analyze it for us. Old Wu, please tell me."

  Old Wu was named.

   The development of the missile is in charge of the Second Academy of Aerospace Science and Technology, and Mr. Wu also belongs to the aerospace system. Therefore, from a normal point of view, Mr. Wu should support the 23rd Institute of the Second Academy of Aerospace Sciences.

  Old Wu looked at the people present, and finally settled in the corner.

"Leaders, we have encountered a lot of problems in the development of our project. Later, with the help of Mr. Qin of Mingzhou Shipbuilding Industry Group, we made a breakthrough. Although Mr. Qin is not our weapon system professional Yes, but he has a lot of knowledge and a long-term vision, now, I want to listen to his opinion first."

What? My opinion?

  Qin Tao was a little surprised. These old guys are all old foxes. They didn't want to offend others, so they pushed themselves out?

  However, although Qin Tao had some resentment in his heart, since he was asked to speak, he was not polite. After all, since he participated in this kind of meeting, he really wanted to use his ability.

"First of all, I know that the 200 kilometers proposed by the navy is a rigid target, and even the target of 200 kilometers is far from enough. It must be able to reach 300 kilometers, or even 400 kilometers." Qin Tao said: "This It's not about launching satellites, but the actual needs of the navy. Our current goal is to be able to intercept enemy aircraft and anti-ship missiles launched by the enemy, but in the future, we will intercept more and more types of targets, not only aircraft Airborne, and there will be ballistic ones.”

   "Ballistic? You mean ballistic missiles. How could that thing be intercepted?" Immediately, those who supported the 23rd Institute began to object.

  One of the great characteristics of ballistic missiles is that they cannot be intercepted, because the falling speed of the thing is too fast, the ballistic trajectory is high, and the interception window is very narrow, so it is impossible to be intercepted.

"Everyone, we don't want to be a frog in a well." Qin Tao looked at those who opposed him: "Even if you don't say that the rubber-covered anti-missile system deployed by Lao Maozi in the 1960s has successfully achieved the purpose of intercepting ballistic missiles, just say that now, the United States The Patriot missile system already has the ability to intercept short-range ballistic missiles, that is, Lao Maozi’s Scud missiles. The S-300V system of the Lao Maozi Army has already set interception of ballistic missiles as a goal during the research and development stage. The Navy If the main air defense ship only has a search distance of more than 100 kilometers, isn't it blind?"

   "However, we can add an additional long-range search radar!"

"If the phased array radar can do it by itself, do we still need a long-range search radar? Of course, this kind of radar can be deployed on warships, but this kind of radar should be used as a supplement before the phased array radar works. After the phased array radar is working, the long-range search radar should stop, which can also save some power. Besides, you must not have considered the demand I just mentioned, right? "

  Qin Tao rolled his eyes at the other party.

   "However, if the S-band is used, how will the missile be guided?"

"Well, I don't know the status of our missile development." Qin Tao said: "So, I still speak from the international technology. At present, the TVM guidance method is a trend. This guidance method can combine semi-active The advantages of guidance and command guidance, if you use this method, you must use the target to illuminate the radar, but this guidance method has begun to fall behind, and advanced anti-aircraft missiles, air-to-air missiles, have begun to use active guidance. "

  Semi-active guidance requires the ability to illuminate the target from the rear. Active guidance is not needed. It only needs to fly within tens of kilometers of the target, and then it can use its own radar to lock the target.

  Missiles of this type have the ability to be fired and left alone. Although in theory they still need to be irradiated in the middle, the final attack is completely autonomous.

   "If our missiles are going to use this type of guidance, or will use this type of guidance in the future, then the target illumination radar is not necessary."

Qin Tao took a look at those unconvinced people, and continued: "Of course, some people will say that I put satellites, and it is impossible to achieve this with our technology. Therefore, I have another way to solve the problem. In our S-band The T/R component of a small-area C-band phased array radar can be added to the main phased array radar, so that the radar of the 14th Institute can have long-range search and target illumination capabilities at the same time."

  Countless people's eyes lit up.

   Yeah, why didn't they think of that?

The large-area C-band is not suitable, because the search distance of this thing is too short to meet the needs of the navy. However, the S-band radar is not accurate enough to complete terminal guidance. Now, in the large-area S-band front On the other hand, adding a small-area C-band front, wouldn't this perfectly solve the problem?

   "Hmph, you sounded good, combining two different radar fronts, how to solve the problem of electromagnetic compatibility?" Some people began to refute Qin Tao's layman's theory.

"The problem of electromagnetic compatibility, we will solve it!" Ben Lao said: "Although Mr. Qin is a layman, the solution he proposed has perfectly solved our problem of not being able to irradiate in the S-band. I think it is The best solution. We have listed 18 technologies that need breakthroughs, and this electromagnetic compatibility is the 19th item!"

   On a warship, there are a lot of electronic equipment, and the interference of these electronic equipment is a big problem.

   "That's right, the problem of electromagnetic compatibility should be solved." Just then, another voice spoke.

  Designed two models, 051 and 052 Destroyer Pan Lao, voiced his support.

   "I think the plan proposed by Mr. Qin can perfectly solve our problem." Elder Wu finally spoke.

   Also from the Second Academy of Aerospace Engineering, Mr. Wu, who was in charge of developing missiles, actually expressed his support for the project of the 14th Institute at this time!

  The faces of the people in Institute 23 suddenly changed.

   "It's getting late. We'll stop here for the morning meeting. Everyone, let's go to the cafeteria for dinner! We'll discuss the relevant decisions in the afternoon." Wu Shengli said.

   It is not possible to make a decision at this time. At noon, the various leaders of the Navy will definitely hold a small meeting to exchange opinions with each other before finally making a decision.

  So, everyone left the conference room one after another.

  Qin Tao walked forward with the crowd alone. After all, it was his first time to participate in this kind of meeting, and he was surrounded by big bosses, so he couldn't talk to him.

  However, within a few steps, hurried footsteps sounded from behind.

  Old Ben rushed over.

   "President Qin, President Qin!"

  Qin Tao turned his head and looked at Old Ben in surprise: "Old Ben, you?"

   "Boss Qin, your proposal is really strategic, let's talk while walking."

   "Well, I really don't understand professional knowledge. What I said just now are all laymen's words."

   "No, these words are very important." Mr. Ben said: "Only laymen can cast aside the limitations of various technical details and put forward pioneering opinions."

  Qin Tao also felt flattered to be so highly praised by Ben Lao.

"There are still many problems we have encountered. For example, the cooling of the radar antenna is a big trouble. The international mainstream solution is water cooling, but this will greatly increase the complexity of the system." Mr. Ben has already proposed a more detailed solution. technical issues.

A radar antenna is a device that converts electrical energy into electromagnetic energy. This conversion efficiency is quite low. Even for active phased array radar, it is about 25%, and the remaining energy becomes heat. .

   If the excess heat is not dissipated, the system should overheat.

   "Water cooling is too complicated. To reduce the difficulty of the structure, we can use air cooling, put the radar antenna in a cover, ventilate the inside, and force the heat to dissipate. You can also use an air conditioner to blow cold air directly inside."

  Ben's eyes lit up.

"Of course, it has to be solved in terms of materials. When we first developed, in order to solve the problem of availability, we can use silicon bipolar transistors or gallium arsenide semiconductor materials. These components need to be in an environment below 60 degrees Celsius. Temperature can work normally, and in the future, when our technology comes up, gallium nitride can be used to greatly increase the working temperature and increase the detection distance at the same time.”

   "Mr. Qin, you are not an amateur, you are too professional!" Elder Ben was very emotional.

  (end of this chapter)