Abstract: A system for heating the sound-reflective mirror surface of a phased array monostatic sodar apparatus. The system has a heat source located at a position that is spaced from the mirror, a control system that controls the operation of the heat source, a working fluid that is heated by the heat source and used to transfer heat from the source to the mirror, and a delivery system that constrains the heated working fluid and delivers it from the heat source to the mirror.

Abstract: A transducer includes a base, a horn, and a central element. The horn includes a first end coupled to the base and a second end extending from the base and having a perimeter that defines a substantially planar face of the transducer, the horn defining a horn length along a horn surface between the first end and the second end of the horn. The central element includes a first end coupled to the base and a second end extending from the base along a longitudinal axis of the horn, the central element defining a central element length along a central element surface between the first end and the second end of the central element, the central element length being substantially equal to the horn length.

Abstract: A housing for a phased array monostatic sodar system with a transducer array that sequentially emits and receives a set of sound beams along different primary axes. The housing includes an enclosure having a plurality of sidewalls, each sidewall of the plurality of sidewalls having an inner surface, the enclosure configured to emit and receive the set of sound beams. Each inner surface of each sidewall of the plurality of sidewalls defines at least a partially elliptical cross-section configured to substantially envelop at least a portion of an angled, conical sound beam of the set of sound beams.

Abstract: A waterproof or water-resistant membrane cover for the acoustic transducer array of a sodar system. The membrane is placed over each transducer of the array. The membrane may be spaced from the array, with a structure such as a frame used to hold the membrane in place relative to the array.

Abstract: A transducer includes a base, a horn, and a central element. The horn includes a first end coupled to the base and a second end extending from the base and having a perimeter that defines a substantially planar face of the transducer, the horn defining a horn length along a horn surface between the first end and the second end of the horn. The central element includes a first end coupled to the base and a second end extending from the base along a longitudinal axis of the horn, the central element defining a central element length along a central element surface between the first end and the second end of the central element, the central element length being substantially equal to the horn length.

Abstract: A method of detecting precipitation with a sodar apparatus that transmits sound beams into the atmosphere, detects echoes returned from the atmosphere, from the echoes determines a Doppler-shifted spectrum comprising the relative strength of the echoes at various Doppler-shifted frequencies, and estimates wind speed and direction. The method includes automatically estimating the presence of precipitation based on the Doppler-shifted spectrum.

Abstract: A housing for a phased array monostatic sodar system with a transducer array that emits and receives multiple generally conical main beams of sound along different primary axes. The housing includes one or more upwardly-directed sidewalls that define a volume between them that is open to the atmosphere at the top, to emit and receive the beams, and an upper lip at the top of at least one wall, defining a curved perimeter at the top of at least some of the volume that closely conforms to the shape of at least one main beam at the location of the lip.

Abstract: A monostatic sodar system includes an array of essentially identical acoustic transducers. Each transducer includes a cone transducer element which generates and receives sound and a horn which guides the sound to and from the cone to a circular or hexagonal active region from which sound is emitted during a sound emission and into which sound is received during a reception of emitted sound that has been reflected by the atmosphere. Each transducer defines a generally hexagonal perimeter shape and occupying a generally hexagonal area of the array. The system includes a signal generator that generates signals that are used to drive the transducers, a phase and switching control, a receiver that receives signals from the transducers, a processor, an open-top enclosure, and a sound reflector within the enclosure.

Abstract: A housing for a phased array monostatic sodar system with a transducer array that emits and receives multiple generally conical main beams of sound along different primary axes. The housing includes one or more upwardly-directed sidewalls that define a volume between them that is open to the atmosphere at the top, to emit and receive the beams, and an upper lip at the top of at least one wall, defining a curved perimeter at the top of at least some of the volume that closely conforms to the shape of at least one main beam at the location of the lip.

Abstract: An array of transducers for a sodar system, and the operation of the array in a monostatic sodar system. The array is made up of a number of individual sound transducers. Each transducer emits sound into the atmosphere and senses emitted sound that has been reflected by the atmosphere. The transducers have a generally circular cross-sectional shape. The transducers are arranged in a generally planar, generally hexagonal grid packing arrangement.

Abstract: An array of transducers for a sodar system, and the operation of the array in a monostatic sodar system. The array is made up of a number of individual sound transducers. Each transducer emits sound into the atmosphere and senses emitted sound that has been reflected by the atmosphere. The transducers have a generally circular cross-sectional shape. The transducers are arranged in a generally planar, generally hexagonal grid packing arrangement.

Abstract: A housing for a phased array monostatic sodar system with a transducer array that emits and receives multiple generally conical main beams of sound along different primary axes. The housing includes one or more upwardly-directed sidewalls that define a volume between them that is open to the atmosphere at the top, to emit and receive the beams, and an upper lip at the top of at least one wall, defining a curved perimeter at the top of at least some of the volume that closely conforms to the shape of at least one main beam at the location of the lip. The sidewalls are lined with a non-woven fiber based sound-absorbing material.

Abstract: A housing for a phased array monostatic sodar system with a transducer array that emits and receives multiple generally conical main beams of sound along different primary axes. The housing includes one or more upwardly-directed sidewalls that define a volume between them that is open to the atmosphere at the top, to emit and receive the beams, and an upper lip at the top of at least one wall, defining a curved perimeter at the top of at least some of the volume that closely conforms to the shape of at least one main beam at the location of the lip.

Abstract: A system and method for correcting wind speed and direction data collected by a sodar or lidar apparatus for the orientation and/or position of the apparatus. There are sensors mounted to the sodar or lidar apparatus that detect the orientation and position of the apparatus. Software is used to adjust in situ the calculations of wind speeds and directions in three dimensions for deviations from some nominal orientation. Software and data structures can be used to cause the inclusion of the orientation and position of the system with the collected data.

Abstract: A method of detecting precipitation with a sodar apparatus that transmits sound beams into the atmosphere, detects echoes returned from the atmosphere, from the echoes determines a Doppler-shifted spectrum comprising the relative strength of the echoes at various Doppler-shifted frequencies, and estimates wind speed and direction. The method includes automatically estimating the presence of precipitation based on the Doppler-shifted spectrum.

Abstract: An array of transducers for a sodar system, and the operation of the array in a monostatic sodar system. The array is made up of a number of individual sound transducers. Each transducer emits sound into the atmosphere and senses emitted sound that has been reflected by the atmosphere. The transducers have a generally circular cross-sectional shape. The transducers are arranged in a generally planar, generally hexagonal grid packing arrangement.

Abstract: A system for heating the sound-reflective mirror surface of a phased array monostatic sodar apparatus. The system has a heat source located at a position that is spaced from the mirror, a control system that controls the operation of the heat source, a working fluid that is heated by the heat source and used to transfer heat from the source to the mirror, and a delivery system that constrains the heated working fluid and delivers it from the heat source to the mirror.

Abstract: A system and method for correcting wind speed and direction data collected by a sodar or lidar apparatus for the orientation and/or position of the apparatus. There are sensors mounted to the sodar or lidar apparatus that detect the orientation and position of the apparatus. Software is used to adjust in situ the calculations of wind speeds and directions in three dimensions for deviations from some nominal orientation. Software and data structures can be used to cause the inclusion of the orientation and position of the system with the collected data.

Abstract: A waterproof or water-resistant membrane cover for the acoustic transducer array of a sodar system. The membrane is placed over each transducer of the array. The membrane may be spaced from the array, with a structure such as a frame used to hold the membrane in place relative to the array.

Abstract: A housing for a phased array monostatic sodar system with a transducer array that emits and receives multiple generally conical main beams of sound along different primary axes. The housing includes one or more upwardly-directed sidewalls that define a volume between them that is open to the atmosphere at the top, to emit and receive the beams, and an upper lip at the top of at least one wall, defining a curved perimeter at the top of at least some of the volume that closely conforms to the shape of at least one main beam at the location of the lip. The sidewalls are lined with a non-woven fiber based sound-absorbing material.