Li Baoqiang's proposal was based on the idea of establishing satellite communications,

Satellite communication system is actually a kind of microwave communication, it uses the satellite as a relay station to forward microwave signals, communication between multiple ground stations, the main purpose of satellite communication is to achieve "seamless" coverage of the ground, because the satellite works in hundreds of thousands, even tens of thousands of kilometers of orbit, so the coverage is much greater than the general mobile communication system,

However, satellite communication requires ground equipment to have a large transmission power, which was not widely used in the previous life.

At present, Li Baoqiang's 400-watt radio station can achieve global contact, but Li Baoqiang is always not satisfied, and the maritime satellite phone commonly used in overseas missions in his previous life makes Li Baoqiang nostalgic.

It just so happened that not long ago he contacted General Tao Zijun of the Kyoto Military Region, and Li Baoqiang learned that there was a satellite ground station equipment and three communication relay satellites in the underground command center of the Kyoto Military Region.

Tao Zijun also wanted to restore the satellite communication system, but he didn't launch a rocket, in fact, Tao Zijun also thought of launching with nuclear missiles, but Tao Zijun didn't have many nuclear missiles, Tao Zijun regarded it as a baby, and he was willing to do it.

Hawking's call reminded Li Baoqiang of the nuclear missile on the Ohio nuclear submarine, which is an intercontinental missile with a range of 8,000 kilometers.

Li Baoqiang put forward the idea of launching a relay satellite with a nuclear missile, and it was transferred to Shangguanyang, who exchanged views with many experts in this field and felt that it was very feasible.

With relay satellites, there are ground consoles, and there are delivery vehicles, but the difference is only the terminal equipment, which is very simple, and a few maritime satellite phones can still be found, although the components were burned by solar storms, but they can still be produced according to the medicine.

After communicating with Tao Zijun, Tao Zijun also recognized this method, since Li Baoqiang is willing to consume three nuclear missiles, Tao Zijun must be secretly happy, where can he not agree?

The restoration of the satellite communication system, which was a big event in the second year of the last days, attracted the attention of many people,

People can't help but hope that more civilizations in the past life will continue to recover, go back to the past, and enjoy modern civilization.

Although this road is difficult and far, it has begun after all, and a good start indicates that the future will be very good.

A satellite communications department was established in the Huaxia Autonomous Region, specializing in the production of terminal equipment, as well as a series of issues related to the compatibility with relay satellites and satellite consoles.

For this emerging sector, it is indeed troublesome to engage in satellite communications.

The satellite communication system consists of three parts: the satellite end, the ground end, and the user end.

The satellite side plays the role of a relay station in the air, that is, the electromagnetic waves sent from the ground station are amplified and then sent back to another ground station, and the satellite star includes two major subsystems: spaceborne equipment and satellite matrix.

The ground station is the interface between the satellite system and the ground public network, and the ground user can also enter and exit the satellite system through the ground station to form a link, and the ground station also includes the ground satellite control center, and its tracking, telemetry and command station.

The user terminal is a variety of user terminals,

In the microwave frequency band, the working frequency band of the whole communication satellite is about 500MHz wide, in order to facilitate amplification and transmission and reduce pitch shift interference, a plurality of transponders are generally set up on the satellite, and each transponder is assigned a certain working frequency band.

Satellite communication mostly uses frequency division multiple access technology, and different earth stations occupy different frequencies, that is, different carriers are used, which is more suitable for point-to-point large-capacity communication.

Time division multiple access technology has also been more widely used in satellite communications, that is, multiple earth stations occupy the same frequency band, but occupy different time slots, compared with frequency division multiple access, time division multiple access technology will not produce intermodulation interference, do not need to use up and down frequency conversion to separate the signals of each earth station, suitable for digital communication, can allocate transmission bandwidth according to the change of traffic on demand, so that the actual capacity is greatly increased,

Another multiple access technology is code division multiple access (CDMA), that is, different earth stations occupy the same frequency and the same time, but use different random codes to encode information to distinguish different addresses.

CDMA adopts the extended spectrum communication technology, which has the advantages of strong anti-interference ability, good security communication ability, flexible scheduling of transmission resources, etc., and it is more suitable for the use of systems with small capacity, wide distribution and certain confidentiality requirements

In the end, researchers from the Kyoto Military Region and the Huaxia Autonomous Region decided to use the medium-orbit satellite communication system, which was used by the maritime satellite telephone in the previous life.

The satellite is 2000 and 20000km from the ground, and the transmission delay is greater than that of low-orbit satellites, but the coverage is also larger.

The medium-orbit satellite communication system can be said to be a compromise between the synchronous satellite system and the low-orbit satellite system, and the medium-orbit satellite system has the advantages of both schemes, and at the same time overcomes the shortcomings of these two schemes to a certain extent.

The link loss and propagation delay of medium-orbit satellites are relatively small, and simple small satellites can still be used.

If both the medium-orbit and low-orbit satellite systems use interstellar links, the delay of medium-orbit system information through the satellite interstellar link subnetwork will be lower than that of low-orbit systems when users communicate over long distances.

And because its orbit is much higher than the low-orbit satellite system, each satellite can cover a much larger range than the low-orbit system, when the orbit altitude is l0000km, each satellite can cover 23.5% of the earth's surface, so only a few satellites can cover the world,

A dozen satellites can provide dual coverage of most of the world, which can improve the reliability of the system by using diversity reception, while the system investment is lower than that of low-orbit systems.

Therefore, in a certain sense, the medium orbit system may be a superior solution for the establishment of a global or regional mobile satellite communication system.

Of course, if it is necessary to provide broadband services for ground terminals, there will be certain difficulties in the medium-orbit system, and the performance of the low-orbit satellite system as a high-speed multimedia satellite communication system is better than that of the medium-orbit satellite system.

At present, there are only three satellites, which can only be satisfied with Asia-wide communication.

Li Baoqiang proposed that the development of satellites and the production of terminal equipment can be done slowly, but it is the first thing to send satellites to the sky first, even if it fails, it is a bold attempt.

Li Baoqiang's idea was also agreed by many people, and the three communication satellites in the underground warehouse of the Kyoto Military Region were transported to Zhoushan.

The USS Ohio nuclear submarine leaned on the dock of Zhoushan Military Port, three nuclear warheads were carefully taken out, and the satellite was installed at the same time at the site of the original nuclear warhead, which was a huge change for the nuclear missile.

Because the weight, shape, and size of satellites and nuclear warheads have changed dramatically, and this change has an unpredictable and potentially fatal impact on the flight of nuclear missiles.

However, many areas of nuclear missiles that need to be improved and adapted have not been transformed, and no one can transform them at present, and those who can be transformed may still be alive, but this is a system project, even if there are so many people who know how to survive, it will not be completed at all.

It's the end of the world, no one can recreate a nuclear warhead, a rocket, the end times are so cruel, but hope still exists,

Isn't it only two years after the end of the world, and on the land of China, with China's communication satellites, the Americans' nuclear missiles are about to launch three communication satellites?

This is the miracle of the end times, bringing people infinite reverie and hope,

Hawking couldn't help but pray that the launch would be successful, because he would lead the nuclear submarine deep into the ocean, launch these three missiles, and go straight beyond the atmosphere, at an altitude of 2,000 kilometers.

This is an unprecedented operation, and Hawking is both excited and worried about the safety of the entire nuclear submarine,