Magnetic probe factor with consideration of probe tilt for near-field measurement
This paper presents a frequency and space dependent analytical model of near-field magnetic probe factor with probe tilt angle for measuring electromagnetic emissions. The principle and derivation of the probe factor are elucidated. The vector-network-analyzer (VNA) measurement of the probe factor is also introduced. The correlation between the measured and calculated probe factors is finally demonstrated.
Radiation from Microstrip Discontinuities
Radically different methods of calculation by Lewin and by van der Pauw are compared. It is shown that the difference in the two sets of results is due not to the difference in method, but to assumptions on the value of dielectric constant to be used when calculating the substrate polarization. Curves show that differences of up to 30 percent can arise from this source, but the differences are much smaller for the larger values of dielectric constant.
A non-contacting probe for measurements on high-frequency planar circuits
A novel magnetic-field probe for internal measurements on high-frequency planar circuits has been designed and tested. It requires no electrical contact with the circuit and has little or no effect on the circuit under test. Using this probe, circuit operation can be verified, and S-parameters of embedded passive and active components can be measured. Amplitudes and phases of currents at arbitrary positions can be measured. Using microfabrication techniques, working probes have been constructed for measurements in the 26.5-40.0-GHz band. Performance characteristics and typical measurements are described. Direct measurements obtained with these probes provide new information on internal circuit operation. The technique can be applied to rapid production testing.<<ETX>>