Development of productivity started in 1981

Chapter 209 Global Positioning System is under preparation

On March 1984, 3, the "Qihang" successfully released three "Messenger 15" communications satellites in a 780-kilometer polar orbit. In the evening of the same day, it entered the atmosphere over the South Indian Ocean according to the planned program, and then returned to its base in northern Myanmar driven by three rotating detonation engines.

In the following three days, Wang Jiankun actively participated in the testing of three "Messenger 3" communication satellites. He mainly piloted the "Thunderbird" hypersonic aircraft to conduct communication connection experiments at high altitudes to verify the communication method between the "Messenger 3" communication satellite and the hypersonic aircraft.

When the Thunderbird turned on the electromagnetic stealth mode, Wang Jiankun found that it could not receive satellite signals. After inspection, he found that he did not consider receiving external signals in stealth mode when designing it, because it was originally a personal aircraft used for long-distance commuting and did not have a special antenna.

At present, except for the cockpit cover and the radar cover in front, the entire fuselage is covered by plasma stealth and optical stealth units. When the electromagnetic stealth is turned on, the plasma on the surface of the fuselage will hinder the transmission of electromagnetic waves to the antenna under the skin.

After discovering the problem, Wang Jiankun immediately asked Chieko to redesign it. Chieko then quickly came up with a new antenna layout diagram. It was very cleverly arranged around the fuselage where it was not easily exposed to radar waves. After updating the antenna layout, the "Thunderbird" quickly solved the communication problem with the satellite. Moreover, because it often flies at high altitudes, it is subject to little interference and the signal is much stronger than that on the ground.

Once the global satellite communication network is built in the future, the aerial navigation of Thunderbird will be more accurate. It can receive ground signals forwarded by satellites and reach any location in the world with relatively high accuracy.

In addition, once the global satellite communication network is completed, the next task will be to start building a global satellite navigation system.

According to the information collected from the United States, they started research and construction as early as 1973, and the current progress is the stage of ground verification and ground coordinate data collection and collation.

In addition, they seem to have encountered difficulties in high-precision time synchronization and are working together to solve the problem.

However, it was relatively easy for Wang Jiankun to solve this problem because his superpowers could play a huge role in this regard.

In fact, satellite navigation is mainly carried out through the following three steps.

The first is to measure the difference in the arrival time of the signal: due to the different distances between the satellite and the receiver, the signal will arrive at the receiver at different times. At the same time, based on the Doppler effect, the receiver can also measure the contraction or expansion of the signal to determine the speed.

The second step is to calculate the distance from the satellite to the receiver: Based on the arrival time of the signal and the propagation speed of the electromagnetic wave, the distance between the satellite and the receiver can be calculated, and then multiplied by the tangent of the farther angle in the triangle to further determine the distance from the receiver to the satellite;

The last step is to determine the receiver's location: after the receiver receives multiple satellite signals at the same time, its precise location is determined by the intersection of several satellite signals. This intersection indicates the location of the receiver, and the height of the receiver can also be determined.

The above three steps all involve time, and accurate time requires an instrument called an atomic clock.

Atomic clocks use the resonant frequency of electron transitions inside atoms. This frequency is very stable and is almost unaffected by the external environment (such as temperature, pressure, electromagnetic fields, etc.). The number of periodic motions that can occur within 1 second is extremely high. For example, a cesium atomic clock can move 1 billion times in 91 second. This greatly improves the timing accuracy of atomic clocks, reaching a level where the error is only 1 second every millions or even billions of years, making it one of the most accurate timing tools in the world.

The basic principle of this atomic clock is somewhat similar to that of a quartz clock. Both use the frequency of a material to measure time, but the atomic clock uses the resonant frequency of electron transitions inside atoms, while the quartz clock uses the resonance of quartz molecular crystals.

The size of the materials used in the two differs by hundreds of millions of times. The manufacture of atomic clocks requires very precise instruments and equipment. In addition, to find the frequency of the cesium atomic clock, a large number of precise experiments are needed to find the time-frequency signal that controls the microwave resonant cavity as the timing standard. The research method of the United States at this time is to first select and collimate: use the state selection magnet to select the atoms at the lower energy level from a large number of cesium atoms at two hyperfine energy levels, and then these atoms form an atomic beam under the action of the collimator, and pass through the microwave resonant cavity without collision.

Then the transition and detection are carried out: the microwave resonant cavity will radiate electromagnetic waves with a frequency close to the resonance frequency of cesium atoms (9, 192, 631, 770Hz). Under the action of electromagnetic waves, some atoms will transition from low energy levels to high energy levels. After the atoms pass through the microwave resonant cavity, the state selection magnet is used again to separate the high energy level atoms from the low energy level atoms, and the detector will detect the number of high energy level atoms;
Finally, there is feedback and adjustment: the closer the frequency of the electromagnetic wave in the microwave resonant cavity is to the resonance frequency of the cesium atom, the more atoms will transition to high energy levels, and the more high energy level atoms will be detected by the detector. When the number of high energy level atoms detected reaches the maximum, the frequency of the electromagnetic wave in the microwave resonant cavity is exactly the resonance frequency of the cesium atom, and the time-frequency signal that controls the microwave resonant cavity can be used as a timing standard.

Wang Jiankun possesses superpowers. He can now "see" the shape of electron clouds and quickly screen out high-energy atoms. He then uses his superpowers to create a detector to quickly determine the time-frequency signals of the microwave resonant cavity.

……

"Jiankun, how's the satellite test going? Is there anything abnormal?"

"Uncle, the test results are very good. Now we can receive satellite signals in northern Myanmar for about 8 hours a day. In a few days, our next batch of satellites will be launched again. By then, we will be able to receive satellite signals 24 hours a day in northern Myanmar and near this longitude."

"Will the next batch be eight Messenger 8s?"

"That's right. The next batch will complete the eight missiles on this line, and then the next batch will complete the entire line with one launch."

"That's pretty fast. That's great. It won't be long before we can build a global satellite communication system, surpassing the two hegemons, the United States and the Soviet Union."

"Uncle, I am still studying the global satellite positioning system. The design of the atomic clock has been basically completed. In a few days, we will launch a test satellite into space for verification. By then, the accuracy of our missiles, laser-guided bombs and other weapons that require navigation will be greatly improved."

"Global Positioning Satellite System? Can it improve the positioning accuracy of weapons?"

"Yes, the United States is currently conducting research. I have collected some intelligence from them. Public cutting-edge research shows that they are stuck in the manufacture of atomic clocks. However, theoretical research and satellite orbits have been basically completed. I plan to launch first to occupy the best orbital resources."

"Seizing the resources they have chosen? Wouldn't that be bad? What if they find out?"

"It shouldn't happen. Once the experiment is completed, we will launch all 24 navigation satellites into space."

"OK then."

(End of this chapter)