Maximum Unambiguous Velocity (V_max) and PRF

Not only is R_max dependent on the PRF, but so is the maximum unambiguous velocity (V_max) that the WSR-88D can determine for a volume of targets. By "unambiguous", we are referring to the WSR-88D's ability to accurately determine the largest Doppler radial velocity with its "first guess" or first pass through the data. The relationship between V_max and PRF can be expressed mathematically as:

Equation (9)

or

Equation (10)

where PRF = pulse repetition frequency (s^-1)
PRT = pulse repetition time (s) = 1/PRF
and = wavelength of energy transmitted.

For a PRF = 1000 pulses/sec (or PRT = .001 s) and = 0.105 m (or 10.5 cm), V_max is 26.25 ms^-1 (or ~ 51 kt).

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