SCATTERING PARAMETERS OF ARBITRARILY ORIENTED SLOT-COUPLED MICROSTRIPLINES

The reciprocity method is extended to analyse arbitrarily oriented slo t-coupled microstrip lines. The case of uniaxially anisotropic dielect ric substrates is considered. The exact Green functions for these anis otropic substrates are used to solve for the unknown slot electric fie ld, from which scattering parameters of a four-port network for this s tructure are obtained by using the reciprocity theorem. Comparison of numerical results for parallel microstrip lines with other available m easured and computed data shows good agreement. It is found that for a rbitrarily oriented microstrip lines, by varying slot inclination the angle coupling level can be widely controlled, and there exists maximu m coupling for a certain value of slot inclination angle. Effects of o ther parameters such as slot length and dielectric anisotropy are also investigated.