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Doppler Radar uses the Doppler effect to determine speed toward or away from the Radar. When a Radar return has a higher frequency than the transmitted pulse, the object is coming closer, and the *difference in frequency determines speed. Lower frequency- object is moving away. This is used by police, and for weather Radar to help detect not only speed but to detect patterns characteristic of tornadoes. Also used for other applications not just military.
You are your own Doppler system using audible frequencies. You can tell when a car, plane, or train is approaching vs moving away.
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What is the main advantage of Doppler radar over conventional weather radar?
Edit-Slight Expansions and simplificationsIn General, the Advantages of Doppler RADAR compared to typical "Pulse" RADAR lies in its capability to differentiate between steady objects and moving objects, Doppler RADAR may also provide "velocity search" which later can be used as a basis for target recognition like the second answerer point (man walking and cars) Doppler effect RadarIn a general type of radar, the signal is transmitted/received in short pulses or bursts. The time width (W) for which the signal is sent/received is very short. And the time between two successive transmitted pulses is called pulse repetition time (PRT). Thus, reciprocal of PRT gives its frequency i.e. PRF = 1/PRT. Similarly, the ratio of time width (W) to PRT is called duty cycle (D). The Radar that works on Doppler effect : it works on the principle of Doppler Effect. This effect is applicable to sound waves and electro-magnetic waves, which travel through some medium or through free space. The Doppler Effect states that when there is relative motion between the source of very high frequency signals and the observer, then frequency shift occurs.In CW radar, a constant amplitude continuous microwave sine wave is transmitted. The echo is also a constant amplitude microwave sine wave of SAME frequency, but of lower amplitude, due to loss of energy during traveling of the wave.While detecting the target like aeroplane, ship, missile etc. the echo undergoes change in its frequency. This change of frequency between the transmitted signal and received echo is used to determine the relative speed and direction of motion of the target. For this following formula is used -V = 1.1 x fd x lThe above is true, but is also worth noting that Doppler radar offer's the forth degree of freedom in radar tracking as Range dot, or Doppler/Range-Rate. With more degrees of freedom then just Azimuth, Elevation & Range, tracking filtering can offer better results in say a Kalman Filter Tracking solution. Doppler profiles can be useful for distinction of distributions the difference between a man walking and a car driving etc (with man-portable radar like BLightER, or MSTAR). Doppler information can be used for SAR and ISAR imagery when the range Doppler matrix is collected at a high fidelity and interpolated correctly for a formation. It also should be noted that Doppler measurement is made via a Fourier transform rather then an statistical process, the statistical process relay own correlation of signal and de-correlation of noise where as the Fourier process is a reordering process and can provide a better signal to noise.
What is radar ranging?
Radar Ranging is an Activity of a RADAR system to measure range of a particular object from the RADAR's own location the object can be aircrafts, ships or other objects like buildings. Usually Ranging is done by means of transmitting a pulse and receive echoes from it where the range is measured from time differences(or Delay) between departure and arrival of pulse , this ranging method is called as "Pulse Delay Ranging" Other ranging method is Doppler based ranging where range is measured by means of Doppler effect EDIT- it seems i need to re-construct the answer
What is a radar mast?
A radar mast is a high platform to mount a radar antenna such as the radar has an unobstructed view.
What is difference between pulse radar and CW radar?
CW or continuous-wave radar cannot determine range due to the lack of a listening period where the radar signal is silent. Pulse radar has a silent listening period (hence the name pulse radar). Therefore it can determine the range of the object causing the return by counting the elapsed time between transmission and receipt of the echo. The above is not quite correct, Continuous Wave Radar and Pulsed Radar differ by there relationship between the Pulse Width (tau) and the scene size (Swath). CW Radar's determine range by Frequency Modulation (FM) ranging this means that they ramp the RF frequency within the pulse during the transmission and are known as FMCW Radar. Pulsed Radar on the other hand use the pulse timing but can also use the FM Ranging trick to enhanced there signal to noise and reduce there probability of interference or detection/interception. CW radar can deduce range by delaying the transmit signal and mixing it with the receive such that it becomes a homodyne receiver and in such cases it is usual to ramp the RF and perhaps use two aerials rather then just one with a duplexer switch like in a Pulse radar system. Edit- hmm i feel the above answer is bit too complex... i don't think typical person would go as far as concerning FM or Pulse Delay Ranging here's my Answer DIFFERENCES BETWEEN PULSE AND CW RADAR Basis -Transmission Pulse RADAR puts delay between transmitting and receiving periods so the time between transmitted pulse and received pulse is different While CW RADAR, Transmit continuously -Antennas Pulse RADAR may use same antenna for Receiving and Transmitting , when transmitting the receiver is "blanked" and while Receiving the receiver is Activated and transmitter is blanked .. this is done by a device called "Duplexer" CW RADAR typically used 2 Antennas, one for transmit another one to Receive since there are no delay to receive as what usually seen in pulse RADAR -Ranging technique Pulse RADAR may use "Pulse Delay Ranging" to provide Range measurements , Frequency Modulation Ranging may also possible , especially for pulse RADAR that transmit many pulses and have very shot time to "listen" example is FMICW (Frequency Modulated Interrupted Continuous Wave RADAR) While CW RADAR provides Range by means of Doppler based Ranging (FM Ranging)
What is theDifference between acquisition radar and guidance radar?
In a Military contact Acquisition Radar normally refers to the Search Mode Radar used to scan and track targets before being "target tracked". In this context the "target tracking radar" is used for track and perhaps illuminating a target. If this radar is being used to guide an weapon to the target it is referred to as a guidance radar. However Guidance radar can also exist in the missile seekers.
Is fmcw radar a doppler radar?
An FMCW radar may make use of Doppler, but it doesn't necessarily.
Who invented Doppler radar?
Christian Doppler
What is the difference between a Doppler radar and a regular radar?
Normal radar sends out radio waves to determine the location of an object. Doppler radar can not only find the location of an object or storm, but using something known as the Doppler effect can determine how fast it is moving towards or away from the radar.
Is Doppler radar used for finding hurricanes?
Yes, Doppler Radar can be used to find all storms!
Where was the first Doppler radar used in the US?
The exact location of where the first Doppler radar system was used cannot be determined because the first radar systems were mobile.
How is a hailstorm tracked?
Doppler RADAR
Can a Doppler radar be used to study tornadoes?
Yes. Doppler radar is one of the most important tools in the modern study of tornadoes.
Doppler frequency equations for janus-x Doppler radar beam configuration?
no
Which other noun starts with Doppler?
Doppler effect and Doppler radar are the two most common compound nouns for the proper adjective Doppler.
Where was the Doppler Radar invented?
At the University of Oklahoma
How is Doppler radar useful?
it is use full by.....
What is the Doppler radar used in?
Weather and warfare.
