Network structure of digital trunking technology

GoTa network structure is shown in figure 1. Terminal, wireless subsystem BSS and dispatching subsystem DSS constitute the basic network structure of GoTa.

In order to support telephone interconnection service, data service and short message service, GoTa can also access switching subsystem, data service subsystem and short message service center in its basic structure.

Among them, the wireless subsystem BSS mainly completes the wireless access functions of various trunking services, data services and ordinary telephone services. BSS is generally composed of BTS and scheduling controller PDC. Wireless transceiver BTS completes the functions of modulation and demodulation of GoTa baseband signal, RF signal transceiver, etc. Scheduling controller PDC completes the allocation of wireless resources, scheduling call control, power control, supports various handovers of GoTa terminals in different coverage areas, and collects and distributes trunked voice data streams.

Another important subsystem is the dispatching subsystem DSS. The scheduling controller PDC is connected with the scheduling subsystem DSS. In addition, the scheduling controller PDC also provides various interfaces to connect the switching subsystem and the data service subsystem to meet the needs of various service expansion of GoTa terminals. The scheduling subsystem DSS mainly completes the cluster scheduling service, which consists of two parts: the scheduling server PDS and the scheduling locator PHR. PDS is the general control point of cluster call, which completes the processing of cluster dispatching call, including identifying cluster users, establishing various cluster calls, such as private call and group call, and judging cluster PTT request. As a scheduling server, PDS also receives trunked voice data from the reverse link and redistributes it to the corresponding forward link according to the nature of the call. PHR completes database management and configuration functions, provides group registration and group member registration for cluster users, provides local information and business permission records of cluster members, and completes call statistics and billing functions.