GoTa Digital Trunking System and It´s Location Service

As a digital trunking system derived from the CDMA2000 technology, the GoTa system has many features and advantages of CDMA system.

Basically a GoTa system can be used in two fields: the private mobile radio system that includes the dispatching system, government Integrated Emergency Response System (IERS) and vehicle location report system, and the public mobile radio system that consists of the cellular mobile phone, radio paging system and cordless phone.

Equipped with positioning equipment such as the Mobile Position Center (MPC) and Position Determining Entity (PDE), a GoTa system can implement the highly efficient positioning function.

1 GoTa System Features and Location Service

1.1 GoTa
GoTa, the abbreviation of "Global Open Trunking Architecture", is a new-generation digital trunking communication system based on the CDMA2000 1x technology. It makes use of many advantages of the CDMA technology and makes improvement and optimization for the digital trunking communication system. It can simultaneously realize multiple services including voice, dispatching and data services. In the aspect of voice services, the GoTa system has the features of high secrecy and low radiation in voice communication. As for trunking services, GoTa can provide diversified services such as the one-to-one private call, one-to-many group call, system call, group call, subgroup call, private PTT services, permanent grouping, and temporary grouping.

    Compared with ordinary TDMA trunking systems, the GoTa system based on advanced CDMA technologies has the following advantages: it has higher spectrum efficiency, larger capacity, better service performance and higher voice quality; and it provides mature and improved traditional mobile network services, including basic telecommunication services, supplementary services, short message service, Intelligent Network (IN) service, additional services and circuit switched data services. In addition, the system can realize real-time terminal positioning with the CDMA positioning technology.

    Based on the CDMA2000 1x data platform, the GoTa system has a high data rate and can provide many new packet data value-added services. It provides a two-way data channel of 153.6 Kb/s, supporting to provide a variety of data services.

    Best of all, it features a powerful trunking dispatching function with quick call setup, and is applicable for professional customer groups and high-end commercial user groups.

1.2 Location Service
The location service, also called the wireless positioning service, is actually a new type of service related to location positioning. It uses positioning technologies of radio networks to obtain location information of terminal users, and provides the users themselves, communication systems or an authorized third party with location information to implement personalized services.

    This service originated from the emergency call E911 in the United States. When a user dials this emergency call number, the national security network can locate the user via the radio network to quickly and correctly handle emergencies concerning social security and emergency rescues. This E911 service is developed into current civil location services later on. Such civil services are mainly applied in vehicle dispatching, location query, child custody, travel services and navigation.

    The location service can be delivered over different radio networks such as GSM/GPRS/EDGE, CDMA95/1x/EV-DO/EV-DV and PHS. Network operators have seen its promising prospects and begun to launch the service on their own networks. ZTE is a leader in the positioning technology of CDMA networks. It has multiple patented technologies that can realize very precise positioning in different environments. With flexible structure and networking, ZTE’s full range of positioning product series have succeed in the long-term and mature commercial uses all around the world.

    As a digital trunking system derived from the CDMA2000 technology, the GoTa system has many features and advantages of a CDMA system. Moreover, some important features of GoTa advantage positioning operation. For example, its base station can provide GPS clock information and mobile phone can use the high-rate chip delay of the Base Station (BS) pilot signal to determine distances. Therefore, the wireless positioning technologies based on the GoTa system can improve positioning precision and speed, and accordingly provide a better location service than other networks.

1.3 Combination of GoTa and Positioning
Basically a GoTa system can be used in the following two fields: the private mobile radio systems that include the dispatching system, government Integrated Emergency Response System (IERS) and vehicle location reporting system, and the public mobile radio system that has the cellular mobile phone, radio paging system and cordless phone.

    GoTa user groups of the private mobile radio system fall into three types: large-scale group/special users,
small/middle-scale enterprises/institutes/organizations, and government/public security departments. Their purpose of using the trunking system is to realize internal communication and dispatching. Enterprises and groups that have deployed ZTE’s GoTa trunking systems can implement multiple enhanced trunking functions with location information provided by the location service. The close combination of the location and trunking call services can provide groups and enterprises using the GoTa system with perfect communication and dispatching solutions.
 In the public mobile radio system, GoTa, similar to the existing GSM/CDMA/PHS systems, can provide popular location applications such as personal location query, surrounding information query and special group care.

2 Applications of Location Service
Equipped with positioning equipment such as the Mobile Position Center (MPC) and Position Determining Entity (PDE), a GoTa system can implement the highly efficient location function. The location service interface can be integrated into interfaces of dispatching or controlling centers, and provides functions such as dynamically querying users’ locations, querying surrounding geographical information, monitoring location distribution of group members, dynamically setting up group calls and tracing the location of group members in real time.
Given below are the applications of location service in different fields.

2.1 In Police Departments
Police departments, like police offices, can use GoTa systems to execute the dispatching of police forces and to implement communication between police and between police and the command center.

    With the integration of location service into GoTa dispatching terminals, the dispatching center can in real time observe the distribution of police forces on the screen map. If the dispatching center is connected to public communication networks such as GSM and CDMA, the location of the traced users can be shown at the same time. Then the center can call and dispatch nearby police according to the information. Therefore, the GoTa system can provide an advanced and effective command way for detection tasks.

    There are also some other applications. For example, a police takes pictures with his mobile phone on an accident site and sends them to the command center. With the positioning function, the center can lock the location of the scene and keep the record. This effectively helps the police collect evidence and speed up detection.

    Moreover, according to the location of a policeman, the location service can, through wireless download and wireless streaming technologies, provide him with relevant information in time, such as the information about nearly entertainment places and places where crimes are usually committed.

2.2 In Logistics
In the logistics industry, to be aware of the exact location of goods is very important for realizing the logistics informationization and improve work efficiency. The correct location of goods refers to information about the flow path of the goods, stop time and location. The electronic map helps the manufacturer, consignor, transportation enterprises, and goods receivers learn the correct information in time.

    At present, in the ocean shipping logistics field, with the wide applications of Global Positioning System (GPS), the problem of tracing goods locations and flow paths has been basically resolved. The current problem that needs to be solved is the goods flow routes and locations on land transport. Now, with positioning terminals such as mobile phones and vehicle mounted stations, dispatchers of logistics companies can, using mobile positioning systems, obtain specific locations of vehicles according to driving license numbers and mobile phone numbers, and dispatch vehicles according to the distance between vehicles and customers. Such electronic technologies help find out the exact locations of a vehicle, and can greatly improve the efficiency of logistics. So they are the development trend of the logistics industry.

    The group call function of the GoTa system provides an effective tool for logistics companies to contact their employees while the location function supports more powerful dispatching ability. With the positioning technology, a logistics company can follow actual shipping routes. In case of any accidents, the company may be informed of the latest location of the vehicle. Therefore, the location service the GoTa system will greatly improve the feedback to customers, shipment rate, telephone appointment rate and customer satisfaction.

2.3 In Hotels
Large hotels have great demands for the trunking communication system to dispatch their service staffs. With the high-precise location function of the GoTa system, proper service commands can be directly and correctly delivered to the staff concerned according to the location of the staff. Consequently, the hotels can reduce the number of employees on duty and customers’ waiting time, and accordingly improve the quality of service.

2.4 In Emergency Departments
Emergency departments are functional departments that should make quick responses to issues related to public security, so they always need effective communication to ensure timely and wide-range information exchange. The GoTa system can well satisfy this demand. Its mobile phone with the location function can provide the command center with information such as the locations of vehicles and rescuer/fireman, offering a strong guarantee for reasonable and fast dispatching.

2.5 In Taxi Industry
Trunking functions fit for the taxi industry well. Considering the wide distribution of taxies in cities and communication between drivers and between drivers and the dispatching center, there is an urgent need for the GoTa trunking system with a location function.

    In the taxi industry, through multiparty voice communication with the surrounding moving driver groups, the dispatching center can quickly respond to service requests from the call center according to locations and driving directions of idle taxis. This will reduce the unload rate of taxis and improve the service quality. If the call center is connected to the GoTa system, various combinations of functions such as trunking calls and positioning will be available, which can further improve the vehicle dispatching efficiency.

2.6 In Airports and Mining Enterprises
Both airports and mining enterprises have strict management over movement of their staffs and machines, which can be realized by the location function of trunking terminals. For example, positioning at airports can help determine whether the locations and distribution of security staff and guards are proper, whether there are any blind areas and how to make dispatch in time. The location service will bring more benefits to the enterprises with such application requirements.

2.7 In Mass Applications
The location service of the GoTa system can provide terminal users with various location-based information queries, such as surrounding information services that help find out hotels, banks and gas stations close to querying users, and mobile Yellow Page services.

    This kind of location service also includes services like "where am I" and "where are you", bus changes, navigation service, and so on.

Manuscript received: 2004-09-20