Patent ID: 7576839
Filing Date: 2009-08-18
Classification: G01S

Abstract:
1. A velocity sensing system which includes: at least one energy source adapted to emit light energy capable of reflection by one or more targets of a plurality of targets within a region, and at least one receiver having a plurality of sensing elements wherein at least one sensing element is configured to sense the reflection of emitted light energy from the energy source from at least one of said plurality of targets within said region, and an activation system associated with said at least one energy source, said activation system being adapted to activate and deactivate the energy source in a cyclic pattern with a selected source frequency, and a shielding system associated with said at least one receiver, said shielding system being configured to block the sensing of reflected light energy from the plurality of targets by said at least one receiver, said shielding system being activated and deactivated in a cyclic pattern with a selected receiver frequency, said source frequency and receiver frequency being selected from different frequency values, and wherein each sensing element of the receiver is configured to generate an output beat signal at a frequency substantially equal to the frequency difference between the receiver frequency and the frequency of the reflected source signal detected by the sensing element, and a processing means configured to measure a frequency change in the output beat signal generated by each of the plurality of sensing elements of the receiver with respect to the frequency difference between the source frequency and receiver frequency and to calculate a velocity component in a known direction for each target of the plurality of targets within the region sensed by the receiver, substantially at the same time.