Views: 9 Author: Site Editor Publish Time: 2019-12-15 Origin: Site
In government, public security, emergency communications and other related fields, narrowband trunked communication systems represented by MPT1327, TETRA, and PDT have the characteristics of short call delay, group calling, and high command and dispatch efficiency, and have been widely used. The advantages of traditional narrowband trunking systems are low frequency bands, small path loss, wide coverage, and low network construction costs. The disadvantages are narrow transmission bandwidth, which can only provide voice services and short data services, and cannot provide video services and mobile services that require large bandwidths. Application business.
With the rapid development of wireless communication technology, the carrying capacity of wireless private networks has been rapidly improved. The current mainstream wireless communication technology, LTE, has been able to support theoretical peak rates of 50Mbit / s for the uplink and 100Mbit / s for the downlink. LTE technology has the advantages of high spectrum utilization efficiency, large bandwidth, and high transmission rate.
In recent years, with the continuous development of video technology, people are not only satisfied with the requirements of "seeing and seeing" and "fixed monitoring", but want to "see clearly" and "monitoring anytime and anywhere", especially In the event of major activities or emergency emergencies, it is even more desirable to be able to carry out rapid monitoring and response to serve the multi-department linkage command. Traditional wired and narrowband trunked access technologies are difficult to meet both mobile and broadband requirements. The LTE broadband trunking system uses TD-LTE as the core technology. It combines the high-speed, large-bandwidth of TD-LTE technology with the resource sharing, fast call establishment, and command scheduling features of digital trunking technology. It is a new generation of broadband The multimedia digital trunking system can support more rich multimedia service types.
Faced with the increasing demand for broadband cluster applications, how to deal with the relationship between narrowband clusters and broadband clusters is an issue we need to consider urgently. LTE broadband clusters and traditional narrowband clusters each have advantages and shortages. The existence of the two is by no means an antagonistic relationship, but should be able to rely on each other and complement each other. They need to exist and apply at the same time. Narrowband clusters have been widely used because of their efficient voice scheduling and strong coverage capabilities. Although LTE broadband trunking technology has high bandwidth and high speed and can provide video and mobile application services, LTE has a small coverage area and a large construction investment.
Utilizing the high coverage characteristics of narrowband clusters and the status quo of large-scale network construction, full coverage is achieved for narrowband clusters, and hotspot coverage is achieved for broadband clusters. When narrow and broadband trunking networks coexist, narrowband trunking is used to provide voice scheduling services, LTE's large bandwidth and high rate characteristics are used, and LTE broadband trunking is used to provide video services and mobile application services. At the same time, narrow and broadband cluster networks should not exist in isolation, but to achieve convergence and intercommunication between the two networks, to achieve voice intercommunication between the two, and improve the performance of wireless scheduling services.
As shown in the figure above, the convergence of narrow and broadband trunking networks is to use converged gateway devices to establish connections between narrow and broadband networks to achieve signaling and voice data communication between narrow and broadband networks. Construct a unified scheduling platform to achieve unified scheduling of broadband and narrowband cluster services.
Taking full advantage of the respective advantages of narrow and broadband networks, enabling the two to integrate and interoperate, and to achieve complementary functions, is the main way to construct a private network cluster system.