Resonance Measurement of Single- and Coupled-Microstrip Propagation Constants

The application of resonant techniques to the measurement of microstrip-line propagation constants is described. A review of the basic theory is given first, showing the great generality of the underlying principle. Then the particular case of a transmission line is discussed and it is shown that excellent theoretical accuracy can be achieved despite the simplicity of the procedure and the mathematics involved. Both the cases of nondispersive and dispersive propagation are covered. Finally, it is shown that the basic method can be extended to the case of symmetrical coupled lines in a straightforward way. Some results concerning practical microstrip lines are presented and compared with theoretical data.