Military Industry of Great Powers: Build the Strongest Flanker

The advantages of phased array radar are obvious, but the technical difficulties are also obvious.

"How to control the phase shift of each antenna here? Such high-frequency scanning cannot be done manually, and the driver does not have the energy. If a computer is used, how can it be theoretically solved?"

Professor Ji's words always hit the nail on the head and hit the key point directly.

It is indeed a difficulty. It is a huge problem even for the United States now, but not for Zhao Guoqing.

This requires a key component, which is a phase shifter.

The United States, which currently has the most advanced technology, still uses microstrip phase shifters, which change the phase of microwave components by changing the length of the microwave signal path. It actively changes the phase and cannot achieve passive control, which is often called an analog phase shifter.

It was not until two thousand years later that the United States moved to the use of numerically controlled phase shifters. By changing the control signal, the microwave diodes were controlled on and off, and the length of the microwave signal path was changed to control the phase of the component. However, this type of phase shifter was not produced Complex and large.

Zhao Guoqing's idea is to use MMIC digital phase shifters and use photolithography technology to make planar transmission lines on the plane of the semiconductor. This changes the microwave circuit from a three-dimensional to a planar one, using a gallium nitride MESFET trench switch. When the gate voltage is 0V, the switch is turned on, and when the gate is -5V, the switch is turned off. This type of phase shifter has a response time. Short, small parasitic capacitance, small size, high precision. As for the difficulty, the gallium nitride crystal has solved it. More than half of the difficulty has been solved, and the rest can be seen clearly.

Zhao Guoqing didn't even explain, but directly drew a circuit diagram, which dispelled Ji Hongbo's doubts.

As for the more advanced direct digital synthesis (DDS) chip phase shifter, it requires extremely high chip manufacturing technology, which is useless. You must know that the DDS chip phase shifter can install the phased array radar in less than 500 grams. If you are not short of money, you can install an active phased array radar on an unmanned aerial vehicle (UAV) and install it on an active radar-guided air-to-air radar.

Ji Hongbo nodded. Phased array technology is the cutting-edge technology in the world. Now we have a clue to do it. Even if it cannot be put on the J-7 fighter, it is still worth doing. Turning it into a vehicle-mounted radar or a land-based radar is also a big killer. ah!

Seeing that Ji Hongbo had not expressed his position, Zhao Guoqing continued to persuade.

"Professor Ji, the research on phased array radar does not conflict with the current Monster Snake III. In fact, we can directly apply the American 1553b bus technology. The current ADC and DAC chips can be used, and the computing chips can also be used. The parallel bus interface can be directly used. Keep it, there are no changes to the PCB computer board, only the design and manufacturing of the radar body have been added!"

Of course, according to Zhao Guoqing's idea, it is natural to train a group of units and technical personnel in this project, such as the research of ADC chips, and then a research institute can be established.

High-performance ADC chips, even 40 years later, will still be a technology that the United States focuses on control, and the country could have planned ahead of time.

There are also computing chips and chip manufacturing. As long as there is demand, the state will invest. When we see results, we will definitely increase investment. This can also avoid the cancellation of a large number of large-scale projects in the 1980s and 1990s.

More importantly, if we make a phased array radar that can be mounted on an aircraft, then vehicle-mounted, ship-borne, and land-based radars will naturally follow suit, which will at least improve the country's radar technology by 20 years and reach the world's advanced level.

Of course, the benefits of this project go beyond that. You can develop a high-performance phased array radar project yourself, and the horizons of the Chinese people have naturally improved.

Zhao Guoqing is obsessed with the peace model project. Can Grumman still use the outdated Doppler radar to fool him?

In fact, although Zhao Zhongshu and Ji Hongbo both showed photos of the Grumman active phased array radar, Zhao Guoqing always wondered whether this was another part of the Americans' strategic technology deception.

When were they equipped with their first active phased array radar?

The information in the media was true and false. Anyway, in his memory, after 2000, they were still researching active phased array radar.

Ji Hongbo expressed his affirmation.

Zhao Guoqing also expressed concern.

"Professor Ji, I recommend that the confidentiality level of this project be the highest, and that all participants follow the highest confidentiality regulations!"

"..."

"National Day, foreign countries now have more advanced active phased array radars. Do we... need them?"

Of course it is necessary. Zhao Guoqing is also speechless. In this era, the country always wants to show off any good things it has, such as gallium nitride crystals and KBBF laser crystals a few years later. This is the world's top technology. It is not only made public, but also sold directly. crystal.

Of course, even if the Americans obtained the KBBF crystal, with their technical reserves and top-notch laboratory conditions, it took them fifteen years to crack the manufacturing process, which shows the technical difficulty of KBBF crystal production.

"Not only is it necessary, Professor Ji, I also suggest that even after we complete the research, we cannot make it public!"

Variable silicon frequency conversion technology, MMIC digital phase shifters, and gallium nitride field-effect high-performance triode transistors are technologies that even the United States has not mastered. If they are proactively disclosed, American radar technology can directly enter the 21st century and allow Americans to They are afraid of us, so at least the five-year honeymoon period cannot be made public.

"Okay, you should also write a feasibility report and briefly outline some technical solutions. According to the normal process, the Science and Technology Committee will organize technical units across the country to conduct demonstrations. You should be prepared. The key technologies must be You do the commendation!"

"no problem!"

Ji Hongbo smiled and said: "Don't be too nervous, you guys. These units are probably also units of the Strange Snake Three transformation project. If you have nothing to do, go to the various workshops."

Zhao Guoqing was helpless, Professor Ji, why did you see me nervous?

…………

After immersing himself in work, time passed quickly. Two days after Zhao Guoqing arrived in B Beijing, Tu Jinda also came. He was the chief designer of the Strange Snake III project. In front of Zhao Guoqing, an original creation, Tu Jinda was a teacher, and he was extremely respected. , even Xu Ming and Jia Pengfei received a lot of attention.

Zhao Guoqing did not stay with these two people, but placed them in the first workshop and the third workshop. Both of them had too much to improve in theory and practice.

But with Zhao Guoqing as a role model here, the two of them have worked hard, and their level has also improved linearly.

Jia Pengfei is already familiar with more than thirty logic gate circuits.

"You design the simplest eight-bit adder and subtractor!"

"Teacher Zhao, this is simple. You only need seven NAND gates to complete it. Look!"

Zhao Guoqing was also helpless. Even Jia Pengfei was unwilling to call him Guoqing and started calling him teacher.

"Master Tu respects you as a teacher, how dare I call you National Day!"