Evaluation of the Digital Access and Cross-Connect System for Use in the Defense Communications System

摘要

The Digital Access and Cross-Connect System (DACS) is communications equipment which provides electronic patching and test access to individual 64 kb/s channels of T1 digital groups (digroups). Equipment such as the DACS is envisioned for use in the Defense Communications System (DCS) where it would interface with existing digital communications equipment such as those developed in the Digital Radio and Multiplexer Acquisition (DRAMA) program. The testing reported herein addressed issues concerning the interfaces and interoperation of the DACS with the DRAMA equipment. Section 2 describes the DACS and the test installation at Scott AFB. The communications techniques used within the equipment are described and various communications terms are defined. Section 3 goes into the test methodology and relates the test configurations to potential application of the equipment in the DCS. Results of the testing are then presented in the remaining sections. Section 4 addresses various functional characteristics of the equipment. Section 5 presents results of interface testing including a characterization of the DACS and the DRAMA digroup interfaces. Section 6 describes testing related to the important topics of synchronization and timing. In Section 7, the performance parameters monitored by the DACS and the DACS alarms are discussed. Section 8 addresses operator interface characteristics of the equipment. Summary findings and conclusions are contained in Section 9. The appendix describes the test equipment employed during the testing.