Phased array acoustic antenna system
AssigneeRadian Corporation
InventorsK. Russell Peterman, Charles Riese, Michael J. Smith
Life of this patent
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Abstract
A sound detection and ranging (SODAR) system for taking wind measurements by sending out acoustic pulses and then measuring acoustic energy reflected back to the instrument by the atmosphere. The acoustic pulses are formed using digital beamforming technology which allows the acoustic pulses to be steered independent of frequency due to a time delay design. Also, the present invention SODAR instrument allows wideband capability that is limited only by the dimensions of the antenna array. Furthermore, the present invention SODAR instrument allows the acoustic pulses to be variably steered and allows multiple acoustic beams to be simultaneously received.
Claims21
A sound detection and ranging (SODAR) system comprising:
- an array of acoustic transducer elements, wherein each acoustic transducer element in said array is responsive to one of a plurality of analog transmit signals for providing a beam of transmitted acoustic energy, wherein each beam of transmitted acoustic energy provided by each acoustic transducer element in said array is combined so as to form a directed beam of transmitted acoustic energy, and wherein each acoustic transducer element in said array is responsive to a reflected portion of said directed beam of transmitted acoustic energy for providing one of a plurality of analog receive signals, said reflected portion of said directed beam of transmitted acoustic energy being reflected by wind in the atmosphere;
- analog signal generating means responsive to digital-to-analog control signals for generating said plurality of analog transmit signals;
- analog-to-digital conversion means responsive to analog-to-digital control signals for converting said plurality of analog receive signals into a plurality of digital receive signals;
- and
- control and processing means for generating said digital-to-analog control signals and said analog-to-digital control signals so as to control said analog signal generating means and said analog-to-digital conversion means, respectively, said control and processing means being responsive to said plurality of digital receive signals for providing an indication of wind characteristics based on the characteristics of said reflected portion of said directed beam of transmitted acoustic energy as compared to the characteristics of said directed beam of transmitted acoustic energy.
A method for determining atmospheric wind conditions utilizing a sound detection and ranging (SODAR) system, comprising:
- (a) providing an array of acoustic transducer elements, wherein each acoustic transducer element in said array is responsive to one of a plurality of analog transmit signals for providing a beam of transmitted acoustic energy, wherein each beam of transmitted acoustic energy provided by each acoustic transducer element in said array is combined so as to form at least a first directed beam of transmitted acoustic energy, and wherein each acoustic transducer element in said array is responsive to a reflected portion of said directed beam of transmitted acoustic energy for providing one of a plurality of analog receive signals, said reflected portion of said directed beam of transmitted acoustic energy being reflected by wind in the atmosphere;
- (b) generating said plurality of analog transmit signals by providing digital control signals to a digital-to-analog converter;
- (c) converting said plurality of analog receive signals into a plurality of digital receive signals;
- (d) processing said plurality of digital receive signals to provide an indication of the radial wind velocity along said directed beam based on the characteristics of said reflected portion of said directed beam of transmitted acoustic energy as compared to the characteristics of said directed beam of transmitted acoustic energy;
- and
- (e) repeating steps (b) through (d) for at least a second directed beam having a differing spatial orientation from said first directed beam;
- and combining the radial wind velocities to determine the wind vector in the plane of the first and second directed beams.
Dependencies are inferred from the claim text.