Application of the Modified Wiener-Hopf Technique to Open Microstrip Structures

The modified Wiener-Hopf technique is applied to the solution of the problem of the guided modes along an open microstrip. The same technique is also used for the problem of exciting the open microstrip by a slit delta function series voltage generator. The technique leads to approximate analytical expressions for the space wave and the surface wave radiation fields(which are continuous spectra) together with the guided modes (which are discrete)... These are needed in microstrip discontinuity and antenna problems. Two independent Wiener-Hopf equations result, one for the LSE modes, and the other for the LSM modes. The two integral equations are converted to algebraic equations by introducing certain approximations related to the case when the strip is not very narrow. Propagation constants for the guided modes, current distribution and impedance are compared with other published results. Significance to the radiation from open-ended microstrip is presented.