Method and apparatus for digital phased array imaging
US4983970A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 28, 1990 |
| Grant date | Jan 8, 1991 |
| Priority date | — |
| Expiry date | Mar 28, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10K11/346
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method for generating a stream of digital data words, each representing an analog signal amplitude from a beam of vibratory energy received by a plurality N of transducers each associated with one of a like number of separate channels of a phased array, uses the steps of: sampling, after a delay of a multiple number of cycles at a fixed frequency F, an analog input signal in each channel at a fixed frequency F for conversion to a digital data word at each sample; then demodulating the digital data word stream in each channel to baseband and reducing the data word rate by a factor D; and phase-rotating the baseband data stream of each channel by a phase difference .DELTA..phi. determined by the focal range R and steering angle .theta. to obtain, along both the sampling delay, a different channel time delay t.sub.d,j, for each j-th channel, where 1.ltoreq.j.ltoreq.N, necessary to steer and focus the beam to a desired angle/range combination. Apparatus for generating the stream of digital data words is disclosed, and uses a special output-switching section in each channel to allow a pipelined coherent summation to be obtained across the entire phased transducer array.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.