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- Second time around echoes are returns from large fixed clutter areas located a long distance from the radar. Because they originate from a large distance, such echoes are returned after a second magnetron pulse has been transmitted. However, they pertain to the first pulse transmitted by the magnetron. Such echoes are range ambiguous but, in addition, second time around clutter will not cancel. This is due to the fact that the phase locking of the COHO applies only to the last transmitted pulse.
- http://www.radartutorial.eu/08.transmitters/tx05.en.html
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What are differences between CW radar and pulse radar?
CW Radar or Continues Wave Radar uses a constant transmission and is usually used for angle only tracking and can be combined with a second emission that is pulses or swept to deuce range using and separate antenna (or on a time schedule in some cases). The CW part of a CW Radar reference to the transition duty Ratio and because Dead and Listen time are over lapped they normally have two antennas. FM CW Radar or Frequency Modulated Continues Wave Radar, is similar to the CW set up but the Carrier Radio Frequency is swept, when processed this data can produce range data. Again the Dead and Listen time our overlapped and it is normal for separated antenna to be used. The Frequency sweep is repeated in successive management ion different angles Pulsed Radar Transmits a short pulse rather then continuously like the FMCW Radar or CW Radar and has a short Dead time and long listen time During the dead time when the transmission pulse is emitted the receiver is blanked to protect it, After the pulse has completed transmission the receiver is opened to receive the returns. This means that the receiver and transmission times are mutually exclusive and therefore the same antenna can used for both jobs. As the pulse is short the transmission peak power maybe higher then the CW Power but is present for less time. A Hybrid Radar is ICW or Interrupted Continues Wave (some times called Interrupted Carrier Wave) which is really a pulse radar with a high duty cycle.
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 the use of pulse generator echo sounder?
A device for measuring depth of water by sending pressure waves down from the surface and recording the time until the echo returns from the bottom.
RADAR or radar?
The original usage was RADAR since it is an acronym (RAdio Detection And Ranging) and people encountering it in written form may have thought it a typographical error were it not capitalized.But now that radar has left the realm of esoteric physics and technology and entered the common man's vocabulary, it is usually seen in its lower-case form. At this time upper or lower-case usage depends on the preference of the user.
What radar do?
At the minimum, a radar is a device that can detect the range of the target object (ie. radar gun used by law enforcement). A more advanced radar can locate the range and direction of the target object (via the azimuth). For example, the old spinning radar antenna seen on TV can locate an object based on the detected range and the direction the antenna is facing at the time. These can still be used to track the weather as clouds can be tracked. The most highly advanced radar can identify just about everything about the target object as if it is in front of you. An example of use is tracking space junk.
What is the total time taken by radar waves to come and go from earth to moon?
The go-return time for a radio/radar echo from the moon is roughly 2.56 seconds.
What is the role of radar in ATC?
Radar system sends out radio waves to detect moving objects in the air. When the echo comes back, time is measured and distance is calculated. This process continues.
What is the difference between chronometers and radars?
Radar measures the time for the echo of a radio wave to return from it and from the direction which it returns. A chronometer is a highly accurate timepiece such as a watch where great accuracy is required. It is also used for determining longitude at sea. Unlike radar, a chronometer does not discharge an echo signal
What are some nonmilitary uses for radar besides weather?
Radar can be used to detect distance to an object by determining round trip echo time. Some uses below: Level monitoring of substances in a container or silo-the radar antenna transmits downward from the top of the container and determines the distance to the top of the substance, allowing the operator to determine the amount of substance in the tank. Radar can be used by vehicle collision avoidance systems. Basically, any time distance to an object is required, radar is an excellent solution.
How much time would elapsed between sending of a radar signal to the moon and the creation of an echo?
Around 2.5 seconds. The distance moon varies between approx 362.6 thousand km and 405.4 thousand km. At the speed of light in space (approx 300,000 km per second), the radio waves would take between 2.42 and 2.70 seconds.
How much time would elapse between sending a radar signal to the moon and the creation of an echo?
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What may occur in a time frame of a second?
11 billion cycles of the radiation from a radar operating at 11 GHz.
What is the duration of The Second Time Around film?
The duration of The Second Time Around - film - is 1.65 hours.
What is the time required for a pulse of radar waves to reach an airplane 5 km away and return?
Radar waves travel at the speed of light, approximately 300,000 km/second, so it would take 1/30,000 second for them to make the 10 km round trip.
How much time would elapse between sending of radar signal to the moon and the creation of an echo?
Not physically possible - since the echo couldn't travel in the vacuum of space. However, depending on the position of the moon - theoretically, it would take between 586 & 656 hours for the echo to return. Edit from Drake Tinker - I'm not entirely certain about this answer. For one thing, we have been studying the moon using radar imaging for years in the hope of finding ice or possibly other useful features should we ever decide to attempt a fully independent base on the moon. Radar uses uses radio waves of varying amplitude and frequency depending on the use and is NOT affected by vacuum. There might have been some confusion due to the use of the word echo, which might be considered a event limited to an atmosphere.
When was The Second Time Around - film - created?
The Second Time Around - film - was created on 1961-12-22.
What are the release dates for Second Time Around - 2013?
Second Time Around - 2013 was released on: USA: 2013
