The principle of radar ranging is based on the propagation characteristics of radio waves in space, measuring the distance between a target object and the radar by emitting radio waves and receiving their reflected signals.

1、 Basic principles

The basic principle of radar ranging is to calculate the time it takes for radio waves to pass from transmission to reception and convert it into distance. Since the propagation speed of radio waves in space (close to the speed of light) is known, the distance between the target object and the radar can be calculated by measuring the time difference.

2、 Specific process

Radar beam emission:

The radar system generates electromagnetic signals through a transmitter, which are radiated into the air through an antenna to form a radar beam.
Radar beam refers to the radio signal emitted from a radar antenna, whose shape and direction can be controlled by adjusting the transmission frequency and waveform. The transmission frequency is usually in the ultra-high frequency (UHF) or sub high frequency (SHF) range, and the waveform can be continuous wave (CW) or pulse wave.

Reflection echo reception:

When the radar beam encounters a target object, some of the energy is absorbed by the object, while other parts are scattered, reflected, or transmitted back.
The receiving end of the radar system will receive these reflected echo signals, which contain the distance, position, and other attribute information of the target object.

Distance calculation:

The basic principle of radar ranging is to calculate the time elapsed from transmission to reception and convert it into distance. This is usually achieved through two ranging methods: time difference ranging and phase ranging.
Time difference ranging: Calculate distance by measuring the time difference between transmission and reception. When the transmitted pulse signal is reflected by the target object and returns, the radar system records the time elapsed between transmission and reception. Since the propagation speed of radio waves in space is known (close to the speed of light), the distance between the target object and the radar can be calculated by multiplying the time difference by the propagation speed.
Phase distance measurement: Calculate distance by measuring the phase difference of the waveform. When the transmitted continuous wave signal is reflected and returned by the target object, the radar system compares the phase difference between the received waveform and the transmitted waveform. Due to the relationship between phase difference and propagation distance, the distance between the target object and the radar can be calculated by measuring the phase difference.

3、 Influencing factors and errors

The accuracy of radar ranging is affected by various factors, including changes in electromagnetic wave propagation speed, atmospheric refraction, and errors in the equipment itself. These factors can lead to certain errors in the ranging results. In order to improve ranging accuracy, a series of measures need to be taken to reduce errors, such as calibrating radar equipment, optimizing algorithms, etc.

4、 Application Fields

The principle of radar ranging has wide applications in multiple fields, including military, aviation, navigation, remote sensing, meteorological forecasting, transportation, etc. It provides powerful technological support for human exploration and practice.

The principle of radar ranging is to calculate the distance between a target object and the radar by emitting radio waves and receiving their reflected signals. This process involves multiple steps such as the transmission of radar beams, the reception of reflected echoes, and the calculation of distance. In practical applications, it is necessary to choose appropriate ranging methods and optimization measures based on specific situations to improve ranging accuracy.