SIMULTANEOUS DATA PROCESSING OF MULTIPLE PCM STREAMS ON A PC BASED SYSTEM

Abstract

The trend of current data acquisition and recording systems is to capture multiple streams of Pulse Code Modulation (PCM) data on a single media. The MARS II data recording system manufactured by Datatape, the Asynchronous Realtime Multiplexer and Output Reconstructor (ARMOR) systems manufactured by Calculex, Inc., and other systems on the market today are examples of this technology. The quantity of data recorded by these systems can be impressive, and can cause difficulties in post-test data processing in terms of data storage and turn around time to the analyst. This paper describes the system currently in use at the Strategic Systems Combined Test Force B-1B division to simultaneously post-flight process up to twelve independent PCM streams at twice real-time speeds. This system is entirely personal computer (PC) based running the Window NT 4.0 operating system with an internal ISA bus PCM decommutation card. Each PC is capable of receiving and processing one stream at a time. Therefore, the core of the system is twelve PCs each with decommutation capability. All PCs are connected via a fast ethernet network hub. The data processed by this system is IRIG 106 Chapter 8 converted MIL-STD-1553B bus data and Chapter 4 Class I and II PCM data. All system operator inputs are via Distributed Component Object Modeling (DCOM) provided by Microsoft Developers Studio, Versions 5.0 and 6.0, which allows control and status of multiple data processing PCs from one workstation. All data processing software is written in-house using Visual C++ and Visual Basic.