English 
Views: 9 Author: Site Editor Publish Time: 2019-11-29 Origin: Site
Emergency communication is a communication method that can provide emergency services temporarily and mobilely after emergencies such as guaranteeing combat readiness, rescue and disaster relief, occurrence of terrorist incidents, and failure of communication networks.
Emergency communication is usually based on wireless. It is required to be able to quickly deploy a communication network and provide communication guarantee. The means of emergency communication mainly include the following:
In emergency situations, there will often be a large amount of traffic in local areas and concentrated periods, so it is critical to maximize the use of existing equipment.
(1) GSM wireless activation half-rate: it can accept the largest number of users without losing a part of the voice quality;
(2) Multi-carrier frequency is enabled for 3G wireless devices: Most manufacturers' devices can now implement multi-carrier with a single board, but only because of the purchase problem, only the single carrier is turned on when it is actually opened, and all can be turned on in emergency;
(3) Expand all hardware capabilities and enhance equipment processing capabilities: use spare parts, allocations, etc. to maximize the processing capabilities of existing hardware platforms (including the Internet, bearer networks, local switches, long-distance switches, gateways, wireless devices, etc. Wait);
(4) Close all software license restrictions, or temporarily expand the license: the maximum processing restrictions on the number of users, CEs, codewords, etc. should be removed. In order to ensure that people with mobile phones can make calls, you can consider turning off the verification of the user balance by the camp account system, and even consider turning off user authentication for the mobile network;
(5) Restrictive measures: In order to ensure normal communication, for wireless networks, 2G networks can consider turning off the data network function to allocate all channels to voice. 3G networks can reduce the user's rate to less than 512Kb / s. Try to improve the efficiency of network use rather than perception. In addition, the protection of the equipment's extreme processing capacity is extremely important, and paralysis of the equipment due to overload cannot occur.
Inmarsat, as a type of satellite communication system, has become a major means of communication in the disaster-hit areas due to its convenience, reliability, independence from local ground conditions, global coverage, all-weather, portability, and mobility. Liaison and the transmission of news and information have played an irreplaceable role.
The L-band used by maritime satellites is commonly known as the golden band. Although its communication costs are expensive and irreplaceable in mobile satellite communications, it is no longer a problem for China's rapid economic development. In emergency applications, being able to keep moving video images, data communications, and voice communications can greatly improve disaster relief.
The emergency communication vehicle is mainly loaded with 2G / 3G and antenna equipment in the emergency vehicle. It is used for people's mass gatherings due to major events (such as the Olympic Games, large outdoor parties, etc.) or unexpected events that cause regional communication interruptions (such as mobile antennas in a region Tower damage) emergency communications.
There are three general transmission modes for emergency communication vehicles, which are optical transmission, microwave transmission, and satellite transmission.
The communication equipment in the emergency communication vehicle usually includes: several sets of RNC (BSC) and Node-B (BTS) equipment, ancillary transmission equipment, power protection equipment, and an aerial antenna system that can be lifted.
The emergency communication vehicle can usually meet the communication guarantees of important conferences, exhibitions and festivals in various provinces, natural disasters, handling stability and maintaining wartime combat readiness.
Ultra-short wave radio stations (radio stations) use a wide range of frequencies, involving multiple frequency bands such as 150 MHz, 200 MHz, 350 MHz, and 400 MHz. Because public communication networks are extremely complex, they often appear vulnerable in the face of disasters. Ultra-short-wave radio communication methods have clear voice, strong anti-interference ability, small size and easy to carry radio stations, and strong mobile communication capabilities. They do not rely on wired and optical fibers. They are particularly suitable for disaster relief and emergency response. Used at the scene of the incident.
The characteristics of ultra-short wave communication are basically "line-of-sight transmission", with only certain diffraction and reflection capabilities. Therefore, if the area to be covered is large, a radio relay station can be appropriately selected as the technical support. Generally, high altitude buildings such as high mountains need to be selected as "radio relay relay" ".
Maintaining a radio emergency response ultra-shortwave repeater in normal times may be the most important means of communication in the event of a disaster.
