Recommendations and Best Practices for creating reusable Test Signal Framework definitions

Critical to the successful implementation of Open System Architecture (OSA) test software, in accordance with the requirements of IEEE 1641[1][2], is the implementation Signal Libraries using the Test Signal Frameworks (TSFs) that provide the test program set (TPS) Developer with the suite of defined signals to be used for the test software. This paper aims to provide insight for the TPS developers and guidance on the best practices to be followed when creating and reusing Signal Libraries. It also considers issues to be kept in mind when bringing together a collection of existing Signal Libraries to be used for testing, and references examples that are available for future developers. The paper considers research into the effects of different methods that could be used for matching the TSFs used in describing UUT test requirements and instrument capabilities. This includes evaluation of their relative merits using a variety of "use cases" and example TSFs. Typical User questions are also considered along with their answers. The example TSFs referenced within the paper represent a collection of Signal Libraries available used in previous demonstrations and brought up to the IEEE Std. 1641-2010 standard. These include Signal Libraries provided as part of 1641 demonstrations and previous reports and form the basis of an OSA Signal Library. The technical analysis considers both symbolic signal expression and signal simulation, to address issues such as signal equivalence, quantization, phase jitter and overall performance. The purpose of the paper being to produce material for inclusion into recommendations and guidelines that will ensure best practice can be followed when generating Signal libraries for a wide range of signal types. This will ensure that Signal libraries are fit for purpose, and achieve the desired level of quality necessary for future matching UUT test requirements against the instrument capabilities. In addition, this will ensure that the UUT requirements are NOT over specified against the instrument capability used to initially implement the test solution. To ensure best practice across OSA RTS users, formal guidelines are required for the process of creating and defining IEEE 1641 TSFs in order to minimize differences between signal libraries and any effects that become apparent when implemented on different ATEs, using different instrumentation. The paper considers guidelines which could form the basis of a recommended practice to ensure standardization across the 1641 user base for use on Military or Commercial Automatic Test Systems (ATS).