Search results
Results From The WOW.Com Content Network
The change of repetition frequency allows the radar, on a pulse-to-pulse basis, to differentiate between returns from its own transmissions and returns from other radar systems with the same PRF and a similar radio frequency. Consider a radar with a constant interval between pulses; target reflections appear at a relatively constant range ...
The radar signals that are reflected back towards the radar receiver are the desirable ones that make radar detection work. If the object is moving either toward or away from the transmitter, there will be a slight change in the frequency of the radio waves due to the Doppler effect.
This technique can change the range the radar detects by changing the delay in transmission of pulses, the velocity the radar detects by changing the Doppler shift of the transmitted signal, or the angle to the plane by using AM techniques to transmit into the sidelobes of the radar. Electronics, radio equipment, and antenna can cause DRFM ...
The frequency of radio waves used by most radars, in the form of microwaves, propagate in straight lines.This generally limits the detection range of radar systems to objects on their horizon (generally referred to as "line of sight" since the aircraft must be at least theoretically visible to a person at the location and elevation of the radar transmitter) due to the curvature of the Earth.
X-band radar frequency sub-bands are used in civil, military, and government institutions for weather monitoring, air traffic control, maritime vessel traffic control, defense tracking, and vehicle speed detection for law enforcement. [1] [2] X band is often used in modern radars.
A radar detector is an electronic device used by motorists to detect if ... (usually the frequency of the radar type being ... While radar's radio waves can expand to ...
The pulse-repetition frequency (PRF) is the number of pulses of a repeating signal in a specific time unit. The term is used within a number of technical disciplines, notably radar. In radar, a radio signal of a particular carrier frequency is turned on and off; the term "frequency" refers to the carrier, while the PRF refers to the number of ...
The concept of passive radar detection using reflected ambient radio signals emanating from a distant transmitter is not new. The first radar experiments in the United Kingdom in 1935 by Robert Watson-Watt demonstrated the principle of radar by detecting a Handley Page Heyford bomber at a distance of 12 km using the BBC shortwave transmitter at Daventry.