Analysis of Some Three-Dimensional Microstrip Discontinuities in Terms of Frequency

In the earty seventies, JOHNS introduced the Transmission Line Matrix (T.L.M.) Method. More recently AKHTARZAD applied this technics to some resonant cavities problems. Using this method, we have studied microstrip discontinuities such as the transition between two microstrip lines of different widths. This discontinuity can be caracterized by an equivalent circuit using lumped parameters. The values of these parameters, in the case of a loss less line have been computed in terms of frequency. The effect of the discontinuity with regard to its position from the ends of the line is observed. The limit case when one of the line width tends to zero shall be presented at the conference. The theorical results can be compared with some experimental ones and with other datas yet published in the litterature.