Radar | Calaculations Flashcards
It takes __.__ seconds for a radio wave to travel out and back for each nautical mile of range
12.36
The radar speed is ___m per microsecond
300
With the time delay being Dt, the range can be found with ___
R = ( c x Dt ) / 2
The maximum unambiguous range will be determined firstly by the ___, because ___
PRF, pulses have to return to the transmitter before the neext ones are sent.
Range ambiguity will occur when the time taken for an echo to return from a target is ___ the pulse repetition time
greater than
To increase the unambiguous range, the PRT must be ___, which means ___ the PRF
increase, increase
The PRF is limited by range, the formula is Max PRF =
80000 / nm
The pulse recurrence period/interval is the time between ___.
pulses
The PRP must be long enough for a pulse to go ___. If the PRP is too ___, this cannot happen
out to the target, and return, short
PRF is the number of pulses ___
per second
A further target requires a ___ PRP and ___ PRF
longer, longer
A ___ PRP means more pulses per second, and a ___ PRF
shorter. higher
PRF =
1 / PRP
The pulse ___ can determine the maximum detection range.
width
The pulse energy depends on pulse ___ and output ___
width power
A long pulse has ___ energy and returns a ___ signal
more stronger
Maximum Theoretical Unambiguous Range in km is found by ___
C / ( 2 x PRF )
PRF, with the range known, is found by ___
C / ( 2 x Range (km) )
The minimum range is found by the pulse ___, plus the recovery time of the ___.
width, duplexer
The minimum range is around ___ the pulse width, as is range resolution
half
The Pulse Width/Length will determine the ___
Minimum range
The longer the pulse, the ___ the energy content of the pulse, and the ___ the possible range
greater, greater
A longer pulse allows for the selection of a ___ frequency
lower
The minimum achievable range is slightly more than ____ of the pulse length
one half
If very low values of minimum range are required, then the pulse must be very ___
dhort
Higher frequencies are ___ prone to attenuation
more
The best theoretical range can be achieved with a ___ pulse length, ___ PRF, and ___ transmitter power
longer, short, increased
