Design And Implementation Of Testing Platform Based On TTCN-3 For TD-LTE Broadband Trunking System

Trunking communication,which is a significant part in wireless communication,is widely used in public safety,transportation,energy and other fields.It plays an important role in many aspects such as safeguarding of large-scale events,dispatching at airports,and enforcement of public security.With the development of communication technologies,industry users are no longer satisfied with traditional voice trunking services.They require broadband data services such as images and videos.Broadband multimedia trunking communication has become a common goal of the whole industry.The B-TrunC system,which proposed by China independently,is a broadband multimedia trunking system based on TD-LTE.With the gradual perfection of the TD-LTE broadband multimedia trunking system,variety of network devices have emerged one after another.It is very important to test these devices.At present,there is no publication on the conformance testing of TD-LTE broadband multimedia trunking protocols.How to design and implement conformance testing has become an urgent problem.To solve the problem,this thesis investigates the following problems.1)This thesis determines the tool and development environment for testing development.Reasonable tool and IDE can effectively shorten development time and reduce development difficulties.Above all,analyzing the structure of the TD-LTE broadband multimedia trunking system.According to its structural characteristics,setting the test target as the protocol conformance testing of Uu-T air interface.Then,the thesis summarizes the similarities and differences among automated testing languages commonly used in other protocol testings.Chooseing the TTCN-3 as the testing language.Finally,analyzing and comparing the development status of all the common test development environments for TTCN-3.TITAN is the one that selected as the test environment based on the project conditions.2)Proposing testing architecture of TD-LTE broadband multimedia trunking system.The test architecture is divided into host-PC and system simulator.The host-PC is further subdivided into abstract test suites and test support components.In addition,the system simulator is divided into TTCN-3 ports and the underlying protocol stack module.3)This thesis designs one TTCN-3 abstract test suite for TD-LTE broadband multimedia trunking system comformance testing.First,this thesis designs the TTCN-3 module function according to relevant test protocol.Analyzing the characteristics of the protocols and summarize the trunking RRC message format.Then,comparing the characteristics of single component and multi component.Thus,selecting the multi one in this thesis and divide the test components.Furthermore,the TTCN-3 abstract test suite implemented in this thesis can complete the testings of trunking paging,establishment of trunking RRC connection and establishment of radio bearers.Designing and implementing the modules and functions of the test suite.Finally,this thesis analyzes all the coding and decoding methods of the TD-LTE broadband multimedia trunking protocol and implements the ASN.1 BER and PER codecs.4)Implementing the TTCN-3 port of the system simulator,and proposing a general port implementation method of the TD-LTE broadband multimedia trunking test platform.5)Testing the test platform and running the test suite separately.For platform testing,dividing the tests into module test and system test.First,using third-party packet analysis software to verify the correctness of the TTCN-3 port.Then using third-party LTE message analysis software to verify the codec implementation by LTE RRC message.Furthermore,testing the system by standard protocol in Linux.Verifing the correctness and completeness of the test platform by combining the test results and the results of the third-party software.Finally,running the TTCN-3 test suite of trunking RRC on the platform.Comprehensively using the third-party packet analysis software and LTE message analysis software to verify the feasibility and correctness of the TTCN-3 abstract test suite.It lays a solid foundation for the development of a more comprehensive TTCN-3 abstract test suite in the future.