The maximum range from which a transmitted radar, lidar, or sodar pulse can be reflected and received before the next pulse is transmitted. This range, r
max
, is given by
r
max
= cT/2
, where T is the interpulse period and c is the speed of light (or speed of sound in the case of sodar).
What is maximum unambiguous range of radar?
The unambiguous range of a radar is the
maximum range at which a target can be located
so as to guarantee that the reflected signal/pulse from that target corresponds to the most recent transmitted pulse.
How is PRF calculated?
The pulse repetition interval (PRI) is the time interval between pulses. It should be noted that PRF and PRI effectively refer to the same feature and are simply related by the expression
PRF=1/PRI.
What is unambiguous range in defense applications?
The unambiguous range of a radar is
the maximum range at which a target can be located so as to guarantee that the reflected signal/pulse from that target corresponds to the most recent transmitted pulse
. The radar range is measured by the time delay between pulse transmission and reception.
What determines the maximum range of radar?
Radar Max Range is determined, ideally speaking,
on the properties of the antenna only
. A signal at a certain frequency is transmitted, reflected, then hopefully, detected. Due to the three-dimensional propagation of radar waves, frequency hold the highest weight in determining range.
What affect does changing PRF have on radar?
A
random unwanted change in the phase angle of the generator
is not likely after a shorter time. Therefore, the radar will be more accurate in the distance measurement. Simultaneously, the pulse repetition frequency changes in this short period of time: it is very higher than the average.
What is blind speed?
The blind speed is
a radial speed of the airplane at which the phase shifting of the echo-signal has the value ±n · 360° between two pulse periods
. With blind speeds moving targets are suppressed by a MTI system like ground clutters
What is maximum ambiguous range?
The maximum unambiguous range (R
max
) is
the longest range to which a transmitted pulse can travel out to and back again between consecutive transmitted pulses
. In other words, R
max
is the maximum distance radar energy can travel round trip between pulses and still produce reliable information.
What are MTI radar parameters?
Moving target indication (MTI) is a
mode of operation of a radar to discriminate a target against the clutter
. It describes a variety of techniques used to find moving objects, like an aircraft, and filter out unmoving ones, like hills or trees.
What is minimum range of radar?
The pulse width (H) determines the minimum range at which targets can be detected. This minimum range is
approximately 1⁄2 the length of the wave burst
. In the case of the 4.5μS pulse, the minimum range would be 675 meters (2,215 feet). This is also equal to approximately 0.36 nautical mile.
Can radar detect size of object?
Size. As a rule,
the larger an object, the stronger its radar reflection and thus the greater its RCS
. Also, radar of one band may not even detect certain size objects. For example, 10 cm (S-band radar) can detect rain drops but not clouds whose droplets are too small.
How do you determine if the radar is accurate?
The performance of a radar system can be judged by the following: (1) the maximum range at which it can see a target of a specified size, (2) the
accuracy of its measurement of target location in range and angle
, (3) its ability to distinguish one target from another, (4) its ability to detect the desired target echo …
How far can radar detect?
This permits target detection at distances from
about 500 to 2,000 nautical miles (900 to 3,700 km)
. Thus, an HF over-the-horizon (OTH) radar can detect aircraft at distances up to 10 times that of a ground-based microwave air-surveillance radar, whose range is limited by the curvature of the Earth.
How do you increase PRF on ultrasound?
Decreasing the pulse repetition period (PRP)
to increase the PRF and the Nyquist limit. Applying a low-frequency transducer to create a small Doppler shift for blood flow velocity.
What is minimum range and pulse length?
MINIMUM RANGE.—Pulse length determines a radar’s minimum range or how close a target can get to the antenna without adversely affecting operations. Minimum radar range is defined as
any distance greater than one-half the pulse length
.
What is a radar sweep?
Overview. The Radar Sweep Controls are
used to control displays of single level sweeps of radar data
, and their display appears in the Main Display window. WSR-88D Level II radar data has three moments or display types: Reflectivity, RadialVelocity, and SpectrumWidth, indicated by the. icon in the Field Selector.
