Pulse-Doppler Radar - Principle

Principle

Pulse-Doppler radar is based on the Doppler effect, where movement in range produces frequency shift on the signal reflected from the target.

Radial velocity is essential for pulse-Doppler radar operation. As the reflector moves between each transmit pulse, the returned signal has a phase difference or phase shift from pulse to pulse. This causes the reflector to produce Doppler modulation on the reflected signal.

Pulse-Doppler radars exploit this phenomenon to improve performance.

The amplitude of the successively returning pulse from the same scanned volume is:

So

This allows the radar to separate the reflections from multiple objects located in the same volume of space by separating the objects using a spread spectrum to segregate different signals.

where is the phase shift induced by range motion.

Read more about this topic:  Pulse-Doppler Radar

Famous quotes containing the word principle:

    The only principle that does not inhibit progress is: anything goes.
    Paul Feyerabend (1924–1994)

    The mode of founding a college is, commonly, to get up a subscription of dollars and cents, and then, following blindly the principles of a division of labor to its extreme,—a principle which should never be followed but with circumspection,—to call in a contractor who makes this a subject of speculation,... and for these oversights successive generations have to pay.
    Henry David Thoreau (1817–1862)

    The principle of subordination is the great bond of union and harmony through the universe.
    Catherine E. Beecher (1800–1878)