Military Industry of Great Powers: Build the Strongest Flanker

Zhao Guoqing then looked at the sixth workshop of digital-to-analog/analog-to-digital conversion chips that he was very concerned about. This workshop also had the largest number of people. Of course, the complexity of the project was also the highest.

Moreover, he did not finish this part of the drawing. He only sketched the signal processing flow chart and described the principle of signal processing.

The so-called conversion of radar wave analog signals to digital signals is to convert the analog radar wave signals into digital signals through specific digital encoding through electronic sampling.

This kind of sampling has a performance loss, because the radar wave is a continuous wave, so the shorter the sampling time, the lower the distortion rate.

Fortunately, on radar, the conversion between analog models and digital signals is much simpler than sounds and images.

Because radar waves can be represented by functions, time, wavelength, frequency, amplitude, and direction can be collected to accurately represent radar waves, or the synthesis of multiple waves.

But sounds and images often have no rules.

But even so, it is extremely difficult to express the entire circuit using transistors in this era.

The method used is still to rub the CPU by hand.

"National Day, how's it going?"

Zhao Guoqing nodded, and the direction was right. Vacuum tubes are the same as transistors. Bipolar and tripolar modes are physically the same. In fact, these national engineers have also conducted very in-depth research on electron tubes.

What they need to do is adapt to the layout of transistor-based large-scale integrated circuits as soon as possible.

"The wiring on the physical level needs to be optimized, otherwise there will still be big problems in doing it physically!"

"How to optimize?"

"Optimize interconnectivity, timing requirements, power distribution, and thermal characteristics. Place cells to reduce signal path length, reduce line latency, and promote efficient chip-level communications."

Because of the resistance of the wire itself, the mutual inductance between adjacent wires, and the coupling capacitance, signal noise, crosstalk, and reflection will occur inside the chip. These effects will cause signal integrity problems, causing signal voltage fluctuations and changes. If serious, they will lead to signal distortion errors. These are easy to make mistakes when making transistor chips for the first time and require step-by-step debugging.

Forty years later, these things were just a matter of pressing a few buttons on the EDA software, simulation calculations, and physical verification were generated with one click. But now, it is a huge system project.

The problem is not just that, the PCB printed circuit board still cannot meet the requirements. The technicians from the 207 factory are simply unable to place the huge circuit on the PCB board.

"Chief Commander Ji, the line density is too high. These high-frequency signals are too close together and easily interfere with each other. They cannot work properly at all!"

Zhao Guoqing followed Ji Hongbo and looked at the drawings. There were many components that needed to be integrated, including inductors, capacitors, resistors, power supply components, and the densely packed pins drawn around the preset chip.

"Each inductor here needs to provide a current of 10A, and the entire eight-phase power supply needs to be thickened under strong current, leaving less space for other places. We have thought of many ways to optimize it, but there is still no way!"

Ji Hongbo asked: "What do you think of National Day?"

Zhao Guoqing tried to ask: "Are you able to make a double-layer circuit board?"

"Double-layer circuit board?"

Zhao Guoqing nodded and said: "After printing the circuit diagram, put an insulating layer on it, and then print a layer of circuit on top."

"..."

Ji Hongbo's eyes lit up, this was a good idea.

"National Day, you, I don't know what to say, you young people are really thinking!"

Zhao Guoqing shook his head. Without the memory of future generations, he couldn't tell. Forty years later, PCB circuit boards can be printed with seven or eight layers.

"Circuits with low current and low power consumption should be placed in the middle to avoid heating and affecting stability. High-frequency circuits should be separated from high-current circuits!"

Hong Min, chief engineer of the PCB project, said: "We understand this principle, but we have never done double-layer printing, and we need some necessary demonstrations!"

Ji Hongbo said: "Verify when it is time to verify. The construction period is quite tight. Please comrades in Factory 207 to overcome the difficulties!"

"Don't worry, we at Factory 207 can fight a tough battle."

It took half a day to just look around. When he returned to the office, Ji Hongbo said, "How is it, National Day? How do you feel about it?"

Zhao Guoqing thought for a while and sighed softly.

Ji Hongbo's expression suddenly changed and he said, "On National Day, if you have any questions, just say whatever you want. There's no need to hide it!"

"Then I'll tell the truth?"

Ji Hongbo said angrily: "What are you talking about? Just say it directly?"

Zhao Guoqing said helplessly: "We don't have a suitable radar. What do you think the Monster Snake Three Modifications project is going to do? I feel like building a building. We are above the ground, but we haven't done the basics yet!"

After Ji Hongbo listened, his body seemed to collapse and he sat leaning on the chair.

"The JL-10 radar has high hopes. To say the least, the 204 radar can also meet certain needs..."

Zhao Guoqing shook his head and said: "What the country needs to solve is beyond visual range operations and all-weather operations. From these two points, the 204 radar is not enough. The detection range is not as far as the range of medium-range air-to-air missiles. Besides, the ground attack There is almost no ability to search for air targets, and all-weather operations are out of the question!"

Ji Hongbo said helplessly: "National Day, you are right, but we have been out of touch with the world for so long. We have not even understood the principles of some of the advanced foreign radars, so at this time, we also need to introduce some equipment. With some technology transfer..."

Zhao Guoqing said nonchalantly: "Of course it's good to be able to transfer technology, but what if it's not possible? Our country has always believed that seeking help from others is better than seeking help from yourself. In fact, I feel like we might be able to give it a try ourselves!"

"Try it, what should you try it on? National Day, you don't know, as far as airborne radar is concerned, there are many research institutes and factories across the country. They have been doing it for decades, but none..." Ji Hongbo said As he spoke, he felt something was wrong. He looked at Zhao Guoqing and said, "Guoqing, do you have any ideas? Is it feasible?"

Zhao Guoqing did not answer, but asked Ji Hongbo, "Professor Ji, do you have paper and pen?"

"Yes, yes!"

Zhao Guo took the pen and paper and drew a vertical line on the paper, with four small Y-shaped antennas lying horizontally on the vertical surface.

Each small antenna emits radar waves forward evenly, and when the four antennas emit radar waves intensively, an interesting phenomenon occurs.

A powerful main lobe beam is formed in the middle area, and four small side lobe beams are formed on both sides.

"National Day, what are you doing?"

Zhao Guoqing really wanted to ask Professor Ji, you have also seen the world abroad, why can't you even see the phased array?

But when I think about it, I understand that a few years ago, foreign countries were still strictly guarding against us. The phased array technology must be kept secret. If the international environment had not changed suddenly, the inspection team would not have seen the phased array at Grumman. array radar.

"Professor Ji, this is a phased array antenna, the simplest planar model!"

"Phaseded array? Phased array technology introduced in electronic publications."

Ji Hongbo was speechless. He rummaged through the drawer and found a photo. He held the photo in one hand and pointed at the image on the photo with his finger.

"Is this what you're talking about?"

Zhao Guoqing looked at it and found that it was similar to the photo Zhao Zhongshu showed him, except that the angle of the photo was different.

He nodded and said, "That's it!"