Introduction
Radar systems are electronic systems that use radio waves to detect objects in the surrounding environment. The system transmits radio waves outward into the air, where they can bounce off of objects in the radar's transmission path. The waves that bounce and return to the radar, called pulses, are then received and analyzed by the radar system, which can then determine the shape, position, and velocity of the discovered objects relative to the radar.
All radars work using the same basic components:
- Transmitter: Generates the desired RF wave at some power level. These waves can come directly from an oscillator or derived using an amplifier or a series of amplifiers.
- Antenna: Takes radiofrequency (RF) energy and transmits it from the transmission line into the environment. The antenna is also used to determine how sensitive the transmission/reception is and the direction of transmission/reception (i.e. unidirectional vs. omnidirectional).
- Receiver: Receives weak signals in the range of frequencies transmitted, amplifies them, then converts them from RF to the original data before it was transmitted (baseband).
- Duplexer: A switch that will either connect the transmitter or the receiver to the antenna. This allows one antenna to be used as both the transmitter and the receiver, may not be included in all radar systems.
- Synchronizer: Controls the timing for the entire radar system. Essentially it determines how often pulses are sent and resets the timing clock for each pulse.
- Indicator: Transforms the received information into an output that can be interpreted by the operator. This is often in the form of a display unit
Below is an example of a simple radar system:
