Why the construction of isotropic antenna is impracticable. An isotropic antenna cannot be constructed in practice because radiated transverse electromagnetic waves require that there be a unique transverse polarization direction. This requirement cannot be achieved in all directions from a single point.

Radar Systems Primary Radar Secondary Radar

Block diagram of Radar System

Tresholding in radar systems is a measure put in place in radar signal processing and decision making to minimize false detections. Tresholding algorithms are used together with Constant False Alarm Rate (CFAR) detection system to improve detection and tracking accuracy in radar systems. A Doppler radar is a specialized radar that employs Doppler effect to obtain velocity information about targets at a distance. This is done by irradiating the target with microwave energy and obtaining the reflected waves. The difference in frequency/phase of the transmitted and reflected waves is therefore used in computing relevant information about the location and velocity of the target.

Key Radar Functions

Radar Range Equation

Radar Range Equation (Cont’d)

Definition of Radar Cross Section (RCS)

Radar Range Equation (Cont’d)

Sources of Noise Received by Radar

Radar Range Equation (Cont’d)

System Noise Temperature

Noise Temperature vs Frequency

Development of Search Radar Equation

Search Radar Range Equation

Scaling of Radar Equation

Major Loss Terms in Radar Equation

Major Loss Terms in Radar Equation

Rectangular Waveguide Attenuation

Example – Airport Surveillance Radar

Example – Airport Surveillance Radar