Conceptual Level Design for a Prototype SYNC3 Software System and SupportingDesign Studies

摘要

The SYNC2 program has been a major element of the Omega system synchronizationprocess for more than a decade. A recent assessment of this program, originally developed in 1975, noted several software, design and documentation deficiencies and concluded that this program was unsuitable as a baseline for continued use. To better serve the Omega community's need for accurate and reliable synchronization, an effort to develop a new synchronization software program, referred to as SYNC3, based on modern estimation practices and software programming techniques, was undertaken. This report initiates the development process by providing several design support studies and by developing a high level conceptual design for SYNC3. To support the design process, several studies were performed to provide a better characterization o the synchronization measurement data set. The availability of Global Positioning System (GPS) based measurement data at all the Omega stations has profoundly changed the approach that may be used in the synchronization process. The characteristics of GPs measurements from all eight stations are examined in this report for a three month period (June 1990 through September 1990). The results of this study are used to establish a measurement model and measurement validation approach in the preliminary SYNC3 design. The second major source of measurement data available for purposes of synchronization is internal VLF measurements. Areas of concern regarding the processing of these measurements include the measurement error characteristics and the Predicted Propagation Corrections (PPGs).