Located close to Beijing and Tianjin, the city of Qinhuangdao is in the center of the Bohai Economic zone. At the end of 2015, the city had a population of 3.0732 million over an area of 7,812.4 square kilometers. The police’s private wireless communication network is critical to command and dispatch of daily task, and plays an important role in major events, executing security tasks, maintaining stability, combating and preventing crimes, and carrying out rescue. It is an irreplaceable tool of the police.
The city is expanding, and the population is growing as a result of the rapid development of the society and economy. The wireless trunking command and dispatch system is taking more load. The security tasks for major events are on the rise, and the scale is becoming larger. The legacy analog trunking system is overloaded, equipment is aged, wireless network coverage and the capacity are limited.
The Qinhuangdao police analog wireless communication private network evolves to a PDT full-digital private network, and ultimately to a PDT+LTE broadband/narrowband convergent network. A new PDT digital trunking network replaces the old analog network to provide functions which the analog network cannot provide, such as LBS and SMS. The mobile control and switching center, which will be connected to the provincial network in the future, need to allow access from MPT base stations, MPT+PDT base stations, PDT base stations, and LTE base stations, paving the way for digital and broadband wireless communication for the police.
The capacity of the new PDT digital trunking network meets the surging traffic requirement during the summer holidays, and the old analog trunking network is kept as a standby network. The new network includes 22 sites, 100 vehicle-mounted terminals, and 5,000 mobile and portable radios, and allows the command and dispatch of the police in all the four districts and three counties of Qinhuangdao.
The PDT network provides wide coverage. 4G LTE covers key areas such as security checkpoints, entrances to the city, intersections, and gates to the government buildings.
The figure below shows the architecture of the 2+4 network.
1. PDT features: GPS positioning, SMS, status message, and data query.
2. Multimedia LTE services: private video call, group video call, private voice call, group voice call, and video streaming.
3. Support 2+4 mixed regrouping, mixed call, unified management, and unified dispatch.
4. Multimedia dispatch: high-definition video backhaul, video pull/push, and MMS.
5. Connected to the Safe City system and Smart Transportation system, and use 4G terminals to pull the video of fixed cameras.
6. Visualized dispatch: connected to the PGIS system to enable location-based dispatch, locate officers, receive reports from terminals, and locate terminals.
7. Visualized staff dispatch: connected to the report receiving and handling system to assign tasks, associate reports with officers, handle reports through SMS, mark reports and locate the report site.
8. Database query: connected to on-demand systems to search stolen cars, fugitives, and criminals.
Caltta 2+4 police digital trunking system provides a wide range of services including 2+4 voice/video group call, high-definition video streaming, mobile policing, and location-based dispatch. It allows flattened, visualized, and unified command & dispatch service, improving the work efficiency of the police and delivering service that meets the demand of front-line emergency response, command, and dispatch. It is an example of information-based policing in Hebei province.