Miniature radio-acoustic sounding system for low altitude wind and precipitation measurements

A method of measuring wind speed, comprising:

• determining a local velocity of sound;
• determining an audio frequency having a wavelength equal to about one-half a wavelength of a radio frequency signal having a first frequency;
• generating a first radio frequency signal having said first frequency;
• transmitting said first radio frequency signal from a first antenna;
• generating a first audio signal having said determined audio frequency;
• transmitting said first audio signal from a first audio transducer, wherein said first radio frequency signal is reflected by said audio signal to form a first return radio frequency signal;
• receiving said first return radio frequency signal at said first antenna;
• measuring at least a first parameter associated with said first return radio frequency signal;
• and
• calculating from said measured at least a first parameter a wind speed.

A method of measuring wind speed, comprising:

• determining a local velocity of sound;
• determining an audio frequency having a wavelength equal to about one-half a wavelength of a radio frequency signal having a first frequency;
• generating a first radio frequency signal having said first frequency:
• transmitting said first radio frequency signal from a first antenna;
• generating a first audio signal having said determined audio frequency;
• transmitting said first audio signal from a first audio transducer;
• receiving a first return radio frequency signal;
• measuring at least a first parameter associated with said first return radio frequency signal;
• generating a second radio frequency signal having said first frequency;
• transmitting said second radio frequency signal from a second antenna;
• receiving a second return radio frequency signal;
• measuring at least a first parameter associated with said second return radio frequency signal;
• generating a third radio frequency signal having said first frequency;
• transmitting said third radio frequency signal from a third antenna;
• receiving a third return radio frequency signal;
• measuring at least a first parameter associated with said third return radio frequency signal:
• calculating from said measured at least a first parameter associated with each of said first, second and third return radio frequency signals a wind speed;
• generating a fourth radio frequency signal having one of said first frequency and a second frequency;
• receiving a fourth radio frequency return signal;
• and
• calculating at least one of a precipitation rate, a quantity of precipitation present in the air, and a precipitation fall velocity.

An apparatus for measuring wind speed at low altitudes, comprising:

• first frequency generator means for generating at least a first transmitted signal having a first wavelength, wherein said first transmitted signal comprises a radio frequency signal;
• first means for transmitting said first transmitted signal and for receiving a first reflected signal;
• second frequency generator means for generating a second transmitted signal having a second wavelength, wherein said second wavelength is about equal to one-half said first wavelength, wherein said second transmitted signal comprises an audio frequency sound energy signal, wherein at least a portion of said first transmitted signal is reflected by said second transmitted signal as said first reflected signal;
• means for measuring a parameter associated with said first reflected signal;
• and
• means for computing a wind speed from said measured parameter.