BRT wireless communication solution

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Wireless WLAN transmission: providing a bearing platform for BRT vehicle business

In recent years, due to the rapid development of motor vehicles, resulting in energy shortages and high energy prices, China ’s large and medium-sized cities have become increasingly congested, and the urban traffic environment has deteriorated. The rapid transit system has been internationally recognized as an effective means to deal with urban traffic problems.

BRT is a brand-new mass transportation mode, usually called "land subway". In terms of speed, capacity, reliability and image, BRT can provide a service level similar to the subway. According to research, after the BRT system is built, passengers save a greater amount of time. For example, diagnosis of in-vehicle terminal faults, in-vehicle terminal status statistics, passenger flow data of passenger flow survey instruments, data transfer of Yangchengtong card swipe, in-vehicle streaming media playback, in-vehicle video surveillance image return, etc., all require a stable, efficient The cost-effective bearing system is completed. As a new bus system, BRT has an intelligent traffic command and dispatch system. The system covers all BRT vehicles and stations along the line. The bearer network responsible for the system's data scheduling and information data transmission and backhaul requires BodaCOM's enterprise-grade WLAN products and high-bandwidth backbone backhaul bridge BodaCOM-2000, which provides high reliability, Highly stable WLAN business support.

BRT service supported by wireless technology

BRT intelligent system needs to realize two-way business between vehicle and dispatch center;

1. Real-time vehicle positioning and large-screen real-time display on the platform;

2. The real-time monitoring of the BRT car by the dispatch center;

3. Real-time voice intercom between dispatch center and BRT;

4. Maintenance of BRT vehicle terminal, real-time download and update of streaming media files;

5. Platform WIFI coverage and WIFI advertising push service;

6. BRT buses realize high-bandwidth WIFI coverage and advertising push services;

In order to meet the above-mentioned business development, it is necessary to build a stable and available, high-bandwidth wireless transmission system, and to achieve full coverage of the stations along the line. Compared with GRPS, GPS, satellite and other technologies, Wifi wireless technology is the best choice. On the one hand, Wifi can provide high bandwidth and can carry the data and monitoring services required for BRT operation. At the same time, the investment is low, which can reduce the overall BRT construction and maintenance costs.

Deploying Wifi wireless at each station of the BRT line will face the following three major challenges:

First, unified control. Since the vehicle business model is dynamic, the wireless network of each station needs to have a consistent strategy and fast roaming characteristics to meet seamless handover and ensure the realization of "real-time transmission" business. At the same time, the Wifi network is highly open, and it is necessary to achieve consistency in security and communication channels.

Second, unified management. How to manage and maintain such a huge wireless network will be a huge problem.

Third, adaptability to the environment. Unlike ordinary wireless systems, in order to ensure good coverage, some equipment of the BRT line wireless system is installed outdoors, and the equipment must withstand the harsh environments of dust, sunlight, rain, high temperature and humidity.

Solution: Professional wireless communication solution

According to the specific application situation of the BRT line wireless transmission system, Bodacom recommends the use of BodaCOM-2000 product solutions to realize wireless signal processing through BodaCOM-2000, and user management, encryption, roaming, management and other functions are all centralized on wireless switches. , Which not only simplifies wireless network deployment, but also facilitates daily maintenance and management of customers.

In the wireless transmission system, a wireless switch is deployed in the command center to manage the entire network of APs. The design of the wireless switch is based on a multi-core architecture, which can provide powerful power to realize the unified control of hundreds of APs across the entire line, effectively realizing the entire line of wireless systems. Unified strategy, such as working channel, security strategy, etc.

BodaCOM-2000 wireless base station is equipped with wireless roaming control function, which can realize high-speed roaming of in-vehicle wireless equipment. In the case of different base stations, it can realize the smooth transition of roaming and realize the technology of zero packet loss.

Considering the working environment of the equipment, the wireless base station at each station platform is a carrier-grade outdoor base station. It has outdoor application scenarios with high requirements for high and low temperature, moisture proof, waterproof, dustproof, and lightning protection. It meets the IP68 standard of GB 4208-93 "Enclosure Protection Level (IP Code)" and can work continuously for 100,000 hours without downtime.

At the same time, for the entire wireless transmission system, including wireless base stations, wireless switches and other equipment, through the intelligent management platform, it can achieve the unified management of wired equipment and wireless equipment, greatly simplifying the maintenance and management costs of the network.