Uncharged lines If we assume a line is initially uncharged, and we apply a signal at the source end, we will launch a forward wave, but we will have initially no backward wave, since there is no source at the load end, and the forward wave will not yet have reached the load to produce a reflecti...
Voltage re fl ection factor We define the voltage reflection factor of the load as Note that despite our use of Z0 and ZL to denote the line and the load impedance, the defintion here only applies to resistive loads, because we have assumed vL = ZLiL, and vL and iL are functions of time. However...
Calligraphic characters As some of the calligraphic characters are a little unusual in appearance, we provide here a table showing the most often used letters paired with their Roman counterparts. The table also, for future reference, gives the names and the Standard International Units of the p...
Characteristic impedance of medium The ratio of the electric field and the magnetic field phasors calculated at any point of space has a constant value called the wave impedance of the medium and denoted by η. Thus E0 H0 = η (8.24) where η = r μ ² . (8.25) The value of this important pa...
Comments The discussion of constitutive parameters has preceded to the present length, largely to provide preparation for electromagnetic courses to be given in later years. For the purposes of the present course, only the linear lossless dielectric, linear soft ferromagnet and linear conductivi...
Complex Poynting vector Frequently we are interested in sinusoidal steady state solutions only, so we define for these the Complex Poynting Vector S = 1 2 E × H∗ . (7.15) The reason for the definition of this additional vector will be made clear in the next section. ...
Double Stub Matching The construction of variable length lines involves the fabrication of low loss sliding contacts for both of the conductors, and as a result variable length lines are expensive. It is thus more economical to use two variable-length stubs and a fixed-length line for matching. ...
Exercises on Metallic Re fl ection 1. Follow the procedure above for the case when the incident wave is linearly polarized along the direction occupied by H in the example just given, i.e. in the direction 2. For the two different polarization...
Exponential solutions This being a second order homogeneous differential equation, we will look for waves with an exponential spatial variation, that is for solutions of the type E = E0 e−γ·r . (8.7) where E0 is a complex phasor independent of position, giving the value of the electric field ph...
Faradays law The circulation of the electric field vector E around a closed contour is equal to minus the time rate of change of the magnetic flux passing through a surface bounded by that contour, the positive direction of the surface being related to the positive direction of the contour by th...
