Fast mobile terminal video signal wireless transmission implementation

One: What is wireless roaming?

In real life, network development has made more and more wireless application scenarios, especially when the terminal is in a mobile state, because the coverage of a single base station has a limited coverage area and insufficient coverage. Therefore, the effective coverage area is increased only by increasing the coverage density. In this mode, the mobile terminal switches signals between multiple radio base stations to implement communication with the base station. For the traditional Internet access, the terminal switches signals between the base stations, and the switching time is not high.

Two: Security system requirements for wireless roaming

Wireless roaming is used in security systems, mainly to meet the mobile video surveillance terminal to transmit data to the upper-level monitoring center through wireless terminals. For the current high-definition surveillance system, the network HD camera video stream is large, especially in multi-channel video. In the case of transmission, the terminal returns a large amount of data, a large load, and a wide coverage area. At the same time, due to the speciality of the wireless monitoring system, the video requirements are high. During the transmission of the wireless video transmission signal, the communication link between the wireless mobile terminal and each base station should meet the requirements of low signal delay and continuous smoothness. The ordinary wireless communication equipment is only for some traditional wireless coverage of the Internet. Such systems have low data flow, narrow area of ​​the Internet access area, and small amount of data carried by the terminal. These do not meet the requirements of wireless mobile monitoring for distance and data transmission. Traditional wireless overlay device firmware cannot achieve true seamless roaming because of the different usage scenarios. The traditional wireless roaming function is only in hardware. For example, after the mobile terminal and the previous base station communication link are disconnected, the terminal will speed up scanning. If the terminal and the other base station re-establish signal links after scanning to the appropriate base station, such roaming will cause signal transmission. Unstable and signal loss. Moreover, the traditional wireless coverage device has low power and low receiving sensitivity, and the overall influence signal coverage range and communication effect cannot meet the data transmission requirements of the HD video camera.

Three: How to choose wireless roaming equipment for security system

In combination with wireless transmission applications, wireless communication signals require long transmission distances, high rates, and stability. It is especially critical for wireless video transmission selection that supports high-speed signal switching. Based on these requirements, our high-speed mobile wireless data switching equipment can meet such needs. It has the following characteristics:

Large power coverage distance

The high-speed mobile wireless data transmission equipment has a radio frequency of 30 dbm, which has a longer communication distance than the traditional WiFi network. With a professional customized high-gain antenna, the effective coverage radius is more than 1 km in an unobstructed environment.

Fast switching

Our company re-customizes and optimizes equipment software according to specific industry applications. For the wireless coverage device in the terminal mode, the communication purpose is fast switched in order to achieve the signal between the base station and the base station. By embedding fast recognition functions in the software, for example, in the wireless terminal device, the signal bandwidth, signal switching, signal floating and other signal indicators are preset in advance according to needs. When the wireless terminal and the A base station are in communication, following the change of the communication signal during the movement, when the system determines that the signal reaches a preset threshold, the device in the terminal mode starts the pre-scan signal mechanism, and when scanning to the adjacent base station B After the signal, the wireless terminal automatically establishes a communication link with the adjacent B base station. During the next move of the terminal, the terminal and the two base stations A and B automatically switch according to the preset signal threshold. Since the mobile terminal is in communication state with the A/B base station, the data is always uploaded during the handover process, so the wireless video signal transmission is not affected, and the video fluency and continuity are ensured.

High transmission rate

For a high-speed mobile switching communication system, a high-bandwidth network capable of supporting high-definition video surveillance signal transmission is required. The traditional network video surveillance signal has a single-channel code stream of more than 2 Mbps. If the mobile terminal needs to transmit multiple high-definition video signals at the same time, The video stream will reach 10Mbps or higher. Therefore, it is necessary to stably transmit such high and continuous data in a moving state, which not only requires high data stream but also requires stable signal reception. Through the optimization of software and hardware of the equipment, our high-speed wireless roaming transmission equipment has the advantages of high transmission rate and high receiving sensitivity. Meet the requirements of high-definition wireless monitoring for data transmission.

Four: equipment main introduction and application

LA-MESH01 is a wireless base station with MESH self-assembly, with a Mini-PCI high-power wireless network card. Widely used in UAV map transmission, individual equipment, cruise ship, rail transit, railway, emergency command, driving school subject 2, subject three mobile network data transmission, with online intelligent scanning, multi-path connection, intelligent path learning and other functions Provides high-bandwidth, low-latency data roaming services in high-speed mobile environments.