TABLE OF CONTENTS In this chapter the framework of Maxwell's theory in differential form representation is introduced. The field quantities are discussed from a phenomenological point of view and related to the corresponding network quantities. Prior knowledge in field theory is not required but may be helpful [1 5]. The transfer of action between electrically charged matter via the electromagnetic field can be used to transfer energy as well as information. Electrically charged particles in rest interact via the Coulomb force. In the case of moving charged particles magnetic interaction also occurs. Electric and magnetic action propagates with a finite velocity, the speed of light, which is 2.998 10 8 ms -1 ? 3 10 8 ms -1. To account for the finite velocity of the propagation of action the concept of the field has proven to be very powerful. The field concept means the assignment of physical quantities to the continuous space. A dynamic field is time-variable. The electromagnetic field can propagate in free-space as well as in media. It does not require a medium of transmission. Electrodynamics is concerned with interrelated electric and magnetic fields. This interrelation always occurs if the fields are time-varying. The electromagnetic field is generated by moving charged matter, and it acts on charged matter. Maxwell's theory summarizes the laws describing the electromagnetic field.
The complete description of the electromagnetic field is specified by two vector fields (i.e., directed fields). These fields are...
