Mode Conversion and EMI Performance of Shielded Cable Assemblies for 10 Gbps Data Transmission

Differential signaling has become the defacto standard for high speed (>1 Gbps) data transmission. Differential crosstalk in high density connectors, footprints, and packages is typically 1/3 or lower than single-ended crosstalk due to field cancellation. A second reason is that differential signaling reduces radiated emissions and improves immunity. Balance, as characterized by mode conversion, is considered to be the metric for the degree of reduction in radiated field strength in differential systems. This paper looks at measured results showing the reduction in emissions due to differential signaling in shielded cable assemblies.