EMC implications of using unshielded twisted pair data busses in the aircraft environment

Practical measurement data has been taken from the EMC tests carried out by BAe on a representative ARINC 629 Data Bus system using prototype hardware. The logical approach is given. The purpose of the tests was to establish the emission and susceptibility characteristics of the bus and its prototype interface hardware, and to compare these measured characteristics with the EMC specifications applicable to civil aircraft. These results are expected to be compared with similar work carried out by other organisations. The test categories covered were conducted and radiated emissions (CE&RE), induced signal susceptibility, and conducted and radiated susceptibility (CS&RS)