Answer Happy

7. The figure shows a cross section of a "microstrip line". The lower electrode is grounded and the wave is TEM. The microstrip has the advantage of be- ing much less costly than either a coaxial line or a rectangular wave guide. It is particularly convenient for transmitting high-frequency signals within printed and integrated circuits. Its main disadvantage lies in the fact that its fields are not limited to the region immediately below the upper electrode. Microstrip lines can therefore interact with other elements in a circuit, un- less they are either spaced or shielded properly. But additional shielding adds complexity and cost. (a) Sketch lines of E and B at a particular instant in time. Use arrows to show directions. (b) In practice, the width of the strip is much larger than its distance to the grounded plane, and edge effects are small. Show that the in- stantaneous value IV of the transmitted power is equal to the Poynting vector integrated over the cross section M. (c) Show that the characteristic impedance Z₂ = V/I is Fore. what value of h/b gives Zo=501?? [Answer: h/b=0.13] Kb-