Introduction BINEX Binary Message Stream

10 Copyright © 2013 Open Geospatial Consortium. 7 Current Message Formats

7.1 Introduction

Models and SWE Common Data encodings were generated for five different files or message streams used in the current GPS framework. Two of these provides the input stream into the EPOCHA process system, while the other three streams represent various output products from EPOCHA. These five streams include a wide variety of predefined messages or records, one of which is encoded in a BINEX binary stream, the second is an XML-based format, a third is currently encoded within binary HDF5 data files, while the fourth and fifth are in a text-based file with pre-defined fixed line-row format. For the BINEX binary data stream, we are able to robustly describe the message components and encodings in SWE Common such that the existing stream can be effectively parse with a generic SWE parser without any modification to the data stream. For the other formats, the messages and data stream have been modeled and described in SWE Common allowing for a highly efficient and easily parsed ASCII or binary stream of data values. The ability to provide SWE Common encodings for these five different data streams, each containing various message types, illustrates that SWE Common is able to support a wide variety of both ASCII and binary messages and data streams. The ability to support highly compact binary streams and ASCII data blocks furthermore illustrates that SWE Common encoding can be highly efficient. In addition, without any custom software or a priori knowledge of these message components or encoding, all of these streams can be parsed by a generic SWE data parser.

7.2 BINEX Binary Message Stream

The first data stream serves as input to the EPOCHA system. This legacy format supports a multiplexed binary stream using a BINEX protocol. A multiplexed stream is one that supports various disparate messages provided in any order. The message types include: ฀ Smoothed Observation Message ฀ Raw Observation Message ฀ Weather Observation Message ฀ Receiver Hardware Information ฀ Satellite Vehicle Information ฀ Monitor Station information Copyright © 2013 Open Geospatial Consortium. 11 ฀ Moving Platform Information TBD ฀ Clock Observations ฀ Satellite Orbital and Clock Initial Condition The message structure of this binary stream has been described in SWE Common in such a way as to preserve the integrity i.e. structure and binary encoding of the current BINEX stream. Access to these data is restricted and not presented here.

7.3 EPOCHA Real-Time Data Files