SGEMP Response of Large, Multiwire Satellite Cables

This paper presents the analytical and experimental results of the first successful SGEMP photon test on large, multiwire satellite cables and high pin density, flight-qualified connectors. These cables and connectors were specifically designed for light-weight, high RF attenuation characteristics and low SGEMP response. The cable configurations evaluated included straight, two connector types as well as a large cable bundle wi th branches. The cable composition consisted of plain, unshielded wires contained within a single overshield and a core of plain, unshielded wires and twisted shielded pairs (TSP). The complexity of the cables ranged from 37, 61 and 98 wires. These configurations, compositions and complexities are typical of those found in actual satellite electrical systems. The complete distribution of SGEMP wire currents was measured for each cable tested and compared to the results predicted by an analytical model. The SGEMP response of the high pin density, flight connectors was also measured. The effects of multiwire coupling in the cables was evaluated and compared to the results predicted by a worst case analytical model based on cable core and individual wire capacitances.