Investigating cable transfer impedance and layout for microsatellite applications

[摘要] ENGLISH ABSTRACT:The co-existence of electronic devices and their attached transmission cables requires acareful planning regarding the energy leakage across cable shields. This leakage posespotential serious problems and impedes system functioning.This thesis pursues an investigation into the EMC cabling protocols for microsatellitesystems. Network analysis techniques are applied in calibrating current probes and torecover the cable transfer impedance, Zr. The calibration approach provides accurateresults for frequencies up to 600MHz. The methods used to determine Zr are based oninjecting a disturbance current onto the outside of the cable-under-test (CUT) andmeasuring the corresponding voltage induced on the centre conductor. Useful results areobtained up to 80MHz with the use of a O.5m length of cable. It is thus proposed that Zris a practical concept for shielding performance evaluation and for the testing of cablephilosophy. The results are usable in classifying cables for verification and signal usage.Further research involves a prediction tool called an EMC ITS that simulates thehardware of a microsatellite system to allow studies on design trade-offs, transmissioncable criteria and placement of devices.

[发布机构] Stellenbosch University