The Bendix Corporation

Other

Patrick N Keating

Takeo Sawatari

Premnathan Naidoo

Rolf K Mueller

Ronald F Steinberg

Roger F Koppelman

Asphalt compositions and products comprising petroleum asphalt, polyolefin, and a wax.

Asphalt modifiers, methods of modifying asphalt, asphalt compositions and methods of making

The elevation angle of a low angle target is accurately measured by subtracting from the received radar signal signals derived from an estimated value of target elevation which reduces the resulting signal to a minimum. The estimated value is an accurate measure of target elevation.

Low angle radar processing means

An underwater viewing system described herein substantially reduces the number of hydrophones in the receiving array and associated circuitry by providing a plurality of transmitting transducers spaced apart by a known distance, each emitting a coded output which is normally a separate frequency. The receiving array, which is preferably square or rectangular, includes a substantial number of receiving hydrophones. A synthetic aperture technique is applied in which the reflected signal arriving at each individual hydrophone is amplified, modulated with a lower frequency reference signal, filtered, digitized and stored in a memory, preferably as part of a computer. The computer also compares each digitized hydrophone signal against sine and cosine reference signals at each frequency and performs a Fourier analysis of each row and column to reconstruct a primary image. It also computes spatial modulation through complex multiplication, addition and subtraction and, through this, reconstructs adjacent images for each transducer frequency such that the ultimate image synthesized and displayed is one in which the effective number of image points is like that of a system in which the number of hydrophones is the actual number multiplied by the number of different transmitted frequencies.

Growing community of inventors

West Bloomfield, MI, United States of America

Patrick N Keating