Spinning focal plane array camera particularly suited for real time pattern recognition

• US 5,990,829 A
• Filed: 07/03/1998
• Issued: 11/23/1999
• Est. Priority Date: 08/26/1997
• Status: Expired due to Fees

• Current Assignee: The United States of America As Represented By The Secretary of Agriculture
• Original Assignee: the united states of america as represented by the secretary of the navy
• Inventors: Garcia, Joseph P.
• Primary Examiner(s): Tarcza, Thomas H.
• Assistant Examiner(s): PHAN, DAO LINDA
• Application Number:
  US09/131,844
• Time in Patent Office: 508 Days
• Field of Search: 342/73, 342/74, 342/75, 342/368, 342/372, 342/359, 343/754, 343/756, 343/757, 343/909
• US Class Current: 342/368
• CPC Class Codes: G06V 10/147 Details of sensors, e.g. sensor lenses fingerprint or palmprint sensors G06V40/13; vascular sensors G06V40/145; eye sensors G06V40/19

Abstract

A computer vision system is disclosed that utilizes a spinning array of podetectors. The array is rotated about the focal plane of a lens and scans all the possible orientations and positions of the edges of the unknown object. In one embodiment, the photodetectors are elongated so as to provide for maximum light gathering ability along the direction of elongation and a minimum light gathering ability in the direction perpendicular to the direction of elongation. In other embodiments, optical means are used to focus the image onto conventional photodetectors while still having the ability to more efficiently determine edge segments of unknown objects. The system efficiently and rapidly implements the wavelet projection transform to characterize-multi-scale edge segment features of an image of an unknown object. An imaging radar system that utilizes a spinning antenna system having frequency scanning provisions is also disclosed.

Claims

1. A radar system comprising:

(a) a plurality of output feeds oriented in a predetermined manner to establish an integration direction and having means for generating an array of elongated far-field spots;

(b) a source for generating a wide-band signal which is applied to each of said plurality of output feeds;

(c) a dish reflector having multiple feeds;

(d) a RF grating located in front of said dish reflector and having means for providing frequency scanning so that different frequencies are directed to different directions along a transverse integration direction of said oriented plurality of output feeds;

(e) channelized receivers respectively connected to each feed for resolving as a function of frequency the direction of return signals along said transverse integration direction;

(f) duplexers for alternately and respectively connecting the feeds to the signal sources and channelized receivers;

(g) means for rotating said plurality of output feeds, said RF grating, said channelized receivers, and said duplexers;

(h) means for converting analog signal received by said switchable antenna into digital signals representative of spatial frequencies;

(i) means for establishing a hierarchy of said digital signals by summing two or more digital signals to create channels and continuing the summing of said created channels over a predetermined number of levels until there is only one level representing the highest level; and

(j) bandpass filters having predetermined center frequencies each being selected to correspond to the spatial frequency represented by each of said digital signals of said hierarchy.

2. The vision system according to claim 1, wherein said means for establishing a hierarchy comprises a plurality of combiners forming a plurality of hierarchial increasing levels.

3. The vision system according to claim 2, wherein said analog signals of said antenna have known spatial frequencies said predetermined center frequencies are selected to be inversely proportional to said hierarchial increasing levels, said predetermined center frequencies having a highest frequency which corresponds to the highest spatial frequency of said analog signals, and the center frequency of a higher hierarchial level being one-half of that of the next lower hierarchial level.

4. The radar system according to claim 1, wherein said means for generating said array of elongated far-field spots comprise geometric and diffractive optical beam reflectors.

5. The radar system according to claim 1 further comprising:

(a) reflectivity means for resolving unknown objects contained in said elongated far-field spots into representative digital quantities;

(b) means for gathering said representative digital quantities; and

(c) means for manipulating and equating said representative digital quantities to predetermined patterns that identify said unknown objects.