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This paper describes the capabilities of using a time domain analysis to simulate the electrical waveforms on the MIL-STD-1553B data bus using the circuit simulation program SPICE. This simulation was developed to analyze the various data bus architectures of the Space Station Freedom (SSF) propulsion module system. The advantages of this model over frequency domain models is that the waveform is directly calculated, not synthesized, providing a more accurate and detailed waveform representation. Also, nonstandard configurations and effects can be modeled with accurate simulation results. The output of the simulation is an electrical waveform which can be measured at any point in the bus architecture. Therefore it is possible to see the distortion effects on the transmitted signal's waveform at any point on the MIL-STD-1553B data bus. This model accurately simulates the stray impedance effects of all bus components, and is flexible enough to examine any transmitted waveform.

The paper describes an advanced MIL-STD-1553-controlled UHF/VHF radio. In previous UHF/VHF radio subsystems, each UHF/VHF radio had a dedicated control head which stored and controlled all radio modes and data. In an advanced architecture, independent multipurpose data entry units are used to control any number of radios, simultaneously, with the aid of a bus control-processor as a data base and mode command controller for the radios and display units. To integrate the system properly, the bus control-processor must have dynamic control of each radio's modes and provide the data to generate each of the display unit's data formats. Processors with advanced software can reconfigure radio parameters to circumvent failures, and also generate valid command modes when receiving conflicting data from the independent data entry unit or associated data inputs.