How "Disaster" games and movies may be afraid of satellite communications

 

Whether it is in the game circle or the film and television circle, the theme of "disaster" seems to have become popular recently. For example, when "Dragon Family" was released, HBO released a trailer for the TV series version of Naughty Dog's well-known game "The Last Survivor", and announced that it would be released in 2023.

 

　　If you want to survive during the game, you need to know how to "communicate". You can hide the monsters hidden in the dark by whispering with various gestures at close range, but if you go out to find food and encounter a sneak attack, To contact the camp, it is almost impossible to use ordinary communication equipment.

Source: Network

This kind of kidnapping and rescue mission is also a key factor in promoting the development of the plot. If you notify the camp to rescue, the game may not be edited.

 

　　The most attractive part of apocalyptic disaster movies is how to survive in the face of shortage of modern tools and resources. The modern tools mentioned here refer to devices with communication functions.

 

　　Just imagine, when faced with being kidnapped by the enemy and surrounded by monsters, you use remote satellite communication technology to let the military base launch nuclear weapons, bombard yourself, and directly Game Over, how can you develop the plot? Monsters definitely don't do it.

 

　　But then again, this scene is almost impossible to happen in the real world, but another type of "disaster" movie is different.

 

　　The movie "Falling", which was a big hit before, can make you feel chills after watching it during the viewing process. The story is about two female protagonists who climbed a 600-meter tower to "heal the soul". When the female protagonist A came down, they accidentally broke the only ladder connected to the top of the high platform. As a result, they had to be trapped at the top of the tower for help. s story.

Source: Screenshot of the movie "Falling"

All they carry with them are mobile phones, drones for taking pictures of the scenery, and safety ropes of about 15 meters. In such a difficult environment, they have encountered the use of ordinary signal bombs for help, the drones failing to help, and the lack of electricity. Eagle attack, auditory hallucinations due to fatigue and other life-threatening situations at any time.

 

　　Of course, the film still ends with a more "satisfactory". The heroine A survived through ropes and some skills through constant psychological suggestion and self-encouragement, which is a more old-fashioned but effective way, but her best friend did not do this. Lucky.

 

　　As long as the electronic equipment in the hand can function, will there not be such an ending of one person dying and one mental breakdown?

 

　　Satellite communication can really save lives

 

　　Although there are certain elements of interpretation in movies, this approach, which is close to "documentary", can indeed bring a certain sense of reality. If separated from film and television, this kind of scene is also typical to a certain extent.

 

　　The United States, the wild countryside, the vast land and sparsely populated areas, and the altitude of 600 meters above the ground are all strongly implying that this is a place where there is no signal possible. In fact, it is also implying that the signal in the suburbs of the United States is very poor.

 

　　It's common sense that you can't communicate without a signal.

 

　　After watching the movie, a discussion on Douban made me think it was too interesting. An old brother in the comment area directly said, "Huawei mate50 has been here for a few months, and there is nothing to do with this movie." Of course it's a joke, but the reason behind it makes people cry.

 

　　The reason is that Huawei and Apple have taken the lead in supporting a feature that is enough to "save" this movie situation: satellite communication.

 

　　First of all, we need to answer a question that everyone is concerned about. Why in this extreme situation, using a mobile phone with satellite communication can send help information, but ordinary mobile phone signals cannot?

RF Wireless World Source: Network

At present, the mainstream mobile communication methods can be roughly divided into two types, one is cellular communication, also called terrestrial communication, and the other is satellite communication.

 

　　In the final analysis, it is because the "sending and receiving" mechanisms of the two are different. When cellular communication establishes contact with the outside world and sends information, it will first receive the information from the ground wireless receiving base station, and then transmit it through a wired method, such as optical fiber, for long-distance transmission, and then enter the network management center and distribute it to the destination base station, and finally transmit it to on the other party's mobile phone.

 

　　This most mainstream communication method can actually be regarded as a wireless-wired-wireless method. The most critical thing is that the coverage, quantity and transmission of base stations have the greatest impact on the entire communication transmission link. In environments with harsh conditions, such as deserts, Gobi, or environments such as the United States where the number of base stations is not large, the deployed base stations and coverage will be seriously affected, resulting in a "no-man's land" of signals.

 

　　Satellite communication greatly simplifies the transmission process. Only the mobile phone needs to transmit the information to be sent to the ground base station, and then it will be transmitted to the near-earth satellite through wireless transmission. The near-earth satellite is used as a relay at this time, and then transmitted to the The ground base station, which is received by the mobile phone at the other end of the ground, is a wireless-wireless-wireless transmission method. The advantage of this is that there is no need to worry about regional environmental problems.

 

　　Take the satellite communication function of Huawei Mate 50 that I have used before. This function requires an application for internal testing in the initial stage. After the application is approved, you can send "satellite messages" through the Changlian APP.

After entering the "Beidou Satellite Messages" interface, select the content for help, confirm the contact, and click the send button. The user needs to move to an open location and follow the on-screen reminder to move. After searching for the satellite, wait for more than ten seconds to send the emergency message .

 

　　On the receiver side, Huawei mobile phones can directly display the location coordinates through the Changlian APP, and mobile phones without the Changlian APP can also receive text messages with help information and location coordinates. At present, only text messages can be sent and received. In the wilderness, being able to seek rescue as soon as possible is the key.

 

　　What is the difference between traditional satellite phones, Huawei and Apple's satellite communications?

 

　　Satellite communication is not a new technology, it can be traced back to the 1970s. Geostationary earth orbit satellite technology, its characteristics are "just like its name", the satellites remain relatively stationary relative to the earth, and only three satellites are distributed in two levels outside the world, because they are only used for military communications; and by the beginning of the 20th century. , medium and low orbit communication satellites have become the protagonist. Relying on the characteristics of high coverage of medium and low orbit satellites, the communication delay is greatly shortened, and it is more suitable for handheld devices; since 2013, it has been operating in very low orbits and has a huge number of The space-based Internet giant constellation quickly broke the circle by relying on wider coverage and iterative updates in technology, and the StraLink plan is its representative.

 

　　In fact, the technology of direct connection of mobile phones to satellites has already achieved "leap development". Through the mobile communication standard protocol formulated by the global mobile communication standard organization 3GPP, using FPGA to make software-defined satellites is enough to provide mobile phones with various Internet services, but only Not so mature.

 

　　Of course, these satellite technologies are still too far away from the general public. If you search for "satellite phone" on Taobao now, you may find that this type of phone does not seem to be related to "satellite communication". an antenna? And some satellite phones that seem to be relatively "modern" also require a huge antenna.

The real problem is actually on the mobile phone. Guo Zhengbiao, the initiator of the Sat5G satellite communication standard and founder of World Domain Netcom, said, "If you want a good signal, you must either make the satellite antenna bigger, or make the mobile phone antenna bigger."

 

　　It is not difficult to explain why the size and antenna of traditional satellite phones are so large. In fact, it is for the consideration of signals, and the signal requirements for voice are far higher than the requirements for short messages.

Source: Photo by Pinwan lzh

We have to take Huawei's "satellite communication" function as an example. The "satellite communication" in the Huawei Mate 50 series uses the first mobile phone Beidou short message communication radio frequency baseband integrated chip independently developed by my country, and the antenna Parts have also been optimized. After all, consumers who are currently pursuing a thin and light body are obviously unable to accept a protruding antenna.

 

　　And if the satellite and mobile phone antennas are enlarged, the satellite communication (transmission speed) can reach a rate of several megabytes, which is equivalent to the previous 3G network.

 

　　Of course, this also has something to do with satellites. For example, Tiantong Satellite provides services for the "big brother"-shaped satellite phone on the market. It provides satellite services such as voice and data, and the satellite communication of the Mate 50 series is based on The short message function of Beidou Navigation Constellation uses high-orbit satellites in geosynchronous orbit, and only provides positioning and short message services.

 

　　The Apple iPhone 14 series on the other end also supports satellite communication, whether it is for the environment or the sending interface, etc., it can be said that it is "the same" as Huawei, but in fact it is another matter in the sky.

Source: Apple press conference

Because the satellite communication in the iPhone 14 comes from Qualcomm's custom baseband, and Qualcomm has a strategic cooperation with the American satellite communication company Globalstar, the latter established the Globalstar satellite communication system is the low-orbit communication satellite constellation group, which belongs to the near-Earth satellite system.

 

　　"The drunkard's intention is not in the wine"

 

　　As more and more capital pours into the satellite communication field and gradually enters the mainstream communication market, it is bound to bring about a wave of "faster and stronger" development.

 

　　Communication expert Ma Jihua said, "Direct connection of mobile phones to satellites is the future trend, and it will be possible to connect in both low and high orbits. This is inevitable for technological development, but it also requires a process of continuous upgrading and evolution."

 

　　However, it is still facing upstream infrastructure support and satellite quantity support; insufficient supply of downstream ecological chains, and policy supervision needs to be considered.

 

　　In February of this year, Geely's Xingji Times has announced that it will launch the world's first consumer-grade mobile phone directly connected to low-orbit satellites as soon as next year, ahead of Huawei and Apple.

 

　　In the international market, mobile communication companies such as Verizon, AT&T, and Nokia have also reached cooperation with Amazon, OneWeb, and AST SpaceMobile.

 

　　Naturally, Google and Apple will not sit still. Google announced that the next-generation Android system will also support mobile phone satellite communication functions. Apple will also provide satellite communication services through cooperation with Globalstar, which will certainly not be limited to "sending text messages", but will expand to Internet access.

Does this mean that on the surface, everyone is trying to make mobile phones support satellite communication functions, but in fact, they are secretly preparing for being able to "steer" the next generation of communication networks?

 

　　The "White Paper on 6G Overall Vision and Potential Key Technologies" pointed out that 6G will achieve global seamless coverage of space-ground integration, and satellite-ground integration networking technology will also become one of the most important potential technologies for 6G networks. In addition, many experts in the field of communication have said that the future 6G network is actually a hybrid of 5G network + satellite communication, which has the advantages of high throughput and high coverage at the same time.

 

　　But for the mass consumer market, there is still a long way to go from "emergency help" to "commonly used functions" like the current mobile Internet access.

Author/lzh

source: https://www.sina.com.cn/