Characterization of Radiating Elements Using Electromagnetic Principles in the Frequency Domain

This chapter looks at the fields produced by some simple antennas and their current distributions in the frequency domain. It observes the fields produced by a Hertzian dipole, a finite sized dipole antenna, and a small loop antenna. The chapter defines the radiating regions of an antenna in terms of the near fields from the far fields and how that is tied to radiation. It presents examples to illustrate what are valid near field/far field modeling including analysis of antennas over an imperfectly conducting earth as in a wireless communication environment. The chapter illustrates the vector nature of the Multiple‐Input Multiple‐Output (MIMO) electromagnetic system through a few simulated numerical examples. The principles of MIMO must be demonstrated using electromagnetics principles. The chapter also looks at the concept of maximum power transfer and efficiency of power conversion from the source to the load. It describes the performance of electrically small antennas (ESAs).