Working frequency of Radar: Select carefully during design
Time : 2022-03-22

Working frequency of Radar

 

The core of radar working principle is that the radar transmits electromagnetic wave of a certain frequency, receives the echo reflected by the target, and determines some states of the target according to the echo. The frequency of electromagnetic wave emitted by radar is its working frequency.

 

The radar frequency band refers to the frequency range in which the radar transmits radio waves. It is measured in Hertz (Hz) or cycles per second (C/s). Most radars work in the ultrashort and microwave bands, with frequencies ranging from 30MHz to 300GHz and a corresponding wavelength from 10m to 1mm.

 

The specific division is as follows:

 

Name Abbre. Freq. Freq. Band Freq. Length
Extremely low frequency ELF 3~30 Hz Extremely long wave 100kkm~10kkm
Super low frequency SLF 30~300 Hz Super long wave 10kkm~1kkm
Ultra-low frequency ULF 300~3000 Hz Ultra-long wave 1000km~100km
Very low frequency VLF 3~30 KHz Very long wave 100km~10km
Low frequency LF 30~300 KHz Long wave 10km~1km
Medium frequency MF 300~3000 KHz Medium wave 1km~100m
High frequency HF 0.3~30 MHz Short wave 100m~10m
Very high frequency VHF 30~300 MHz Metric wave 10m~1m
Ultra-high frequency UHF 0.3~3 GHz Decimeter wave 1m~10cm
Super high frequency SHF 3~30 GHz Centimeter wave 10cm~1cm
Extremely high frequency EHF 30~300 GHz Millimeter wave 10mm~1mm
To high frequency THF 300~3000 GHz Decimillimeter wave 1mm~0.1mm

 

Wave band symbol Frequency Range (GHz) Wave length range (mm)
UHF 0.3~1.12 GHz 1000~267.9 mm
L 1.12~1.7 GHz 267.9~176.5 mm
LS 1.7~2.6 GHz 176.5~115.4 mm
S 2.6~3.95 GHz 115.4~75.9 mm
C 3.95~5.85 GHz 75.9~51.3 mm
XC 5.85~8.2 GHz 51.3~36.6 mm
X 8.2~12.4 GHz 36.6~24.2 mm
Ku 12.4~18 GHz 24.2~16.7 mm
Ka 26.5~40 GHz 11.3~7.5 mm
Q 30~50 GHz 10.0~6.0 mm
U 40~60 GHz 7.5~5.0 mm
M(V) 50~75 GHz 6.0~4.0 mm
E 60~90 GHz 5.0~3.3 mm
W 75~110 4.0~2.7 mm
F 90~140 GHz 3.3~2.1 mm
D 110~170 GHz 2.73~1.76 mm
G 140~220 GHz 2.1~1.4 mm
R 220~325 GHz 1.4~0.9 mm

 

The wavelengths of radars in different bands are different

 

1, Short wavelength: high resolution, poor penetration and easy to be absorbed;

2, Long wave length: low resolution and strong penetration.

 

Radar functions in different bands

 

Search radar: working frequency band (VHF, UHF, L) ;

Search and tracking radar: working band (L, S, C) ;

Fire control radar / Imaging radar: working band (C, X, Ku) ;

Missile carrier radar: working band (X, Ku, K, Ka, V, U, W) .

 

Radar frequency selection:

Although radar can work in a wide frequency range, different frequencies have different working characteristics and are suitable for different purposes. Therefore, the frequency must be carefully selected when designing a radar.

Radar frequency has obvious influence on radar performance such as antenna transmit gain, antenna effective receiving area (at a certain transmit gain), transmit power, receiver noise, propagation loss, meteorological echo etc. This matters a lot when choosing the type of radar and its important indicators such as action distance, accuracy, resolution, anti-interference ability, volume weight, mobility, cost and so on.

Therefore, the radar frequency is the most important parameter of the radar parameters.