Research And Implementation Of Adapter In TETRA Digital Trunked Interoperability Test System Based On TTCN-3

ABSTRACT:TETEA digital trunked interoperability test system, which is used for interoperability test of TETRA terminals, can guarantee the interconnection between the switching and management infrastructure and the terminal equipments for different manufacturers. As the adapter in TETEA digital trunked interoperability test system based on TTCN-3has the function of air interface data receiving, MAC layer data processing and LLC layer data processing, it is an important part in TETEA digital trunked interoperability test system. Therefore, the research and implementation of system adapter is the key point of the development of TETEA digital trunked interoperability test system.First of all, based on the summary of the development situation of system adapter at home and abroad, the structure of TETEA digital trunked interoperability test system is stated, then service functions of TETRA digital trunked system under test and interfaces among each components of TTCN-3test system are analysed, the structure of system adapter, MAC layer PDU and LLC layer PDU are stated. Then according to the key technologies of the network port data acquisition, MAC layer data parsing and LLC layer data parsing, data format of protocol analyzers, processing procedure of data initialization, up/down-link data division, message fitering, filling bit, message fragment and reorganization, PDU union, basic link and advanced link are designed. Next, on TTworkbench platform, processing module of bit-stream, data initialization, message of MAC layer reorganization, message of MAC layer truncation, data of LLC layer, configuration and PDU judgement are developed by Java language, in order to achieve the function of the network port data acquisition, MAC layer data parsing, LLC layer data parsing and system adapter deployment. Finally, according to the theory of the black box, adaper in TETEA digital trunked interoperability test system based on TTCN-3is tested by using TTworkbench, and the results of tests show that the function of the network port data acquisition, MAC layer data parsing, LLC layer data parsing are implemented by system adapter, which can satisfy the demands of users.