The present invention relates to position detection methods and apparatuses. In particular, the present invention relates to a method and apparatus for approximating a source position of a sound-causing event for determining an input used in operating an electronic device.
There are several known techniques for approximating the position of objects using acoustics, light and radio-frequency waves. These types of localization technologies have a wide array of applications, including, for example, use in navigation and medical applications.
In the field of acoustics, one type of sonar technology generates sound waves that can be reflected off of objects. An acoustic wave may be generated and sent out in a particular direction. If the acoustic wave encounters an object, the acoustic wave is reflected back to the source position. The time-of-travel for the acoustic wave to be sent out and reflected back is used to determine a distance of the object from the source position.
More advanced acoustic wave reflection and detection techniques exist. For example, ultrasounds can map a three-dimensional object by bouncing acoustic waves off the object.
Another type of acoustic application includes devices that use an array of microphones to record sounds. A typical use for a microphone array is to detect the direction of a voice in a room and to perform signal processing so as to enhance the voice recording from that direction.
Another type of acoustic localization technology is passive sonar. Passive sonar devices listen for sounds emitted by designated objects. For example, passive sonar technology is often used to detect underwater vessels and marine life. Typical passive sonar applications look for sound over large underwater domains. The sounds that are detected and processed by such applications are continuous signals, such as emitted by submarines. These sounds may last seconds or even minutes. In order to process continuous sounds, passive sonar applications transform detected signals into the frequency domain, and apply complex frequency-based processing methods to determine signal delays.
Triangulation is one common technique used to identify position information of objects. Triangulation typically uses radio-frequency (RF) waves. A device can be located by having an RF transmitter that emits signals detectable to a matching receiver. The receiver triangulates signals received from the transmitter over a duration of time in order to determine the transmitter""s position.
The foregoing needs, and other needs and objects that will become apparent for the following description, are achieved in the present invention, which comprises, in some aspects, a method, apparatus, system and device that approximate a source position of a sound-causing event for determining an input used to operate an electronic device.
In an embodiment, sound caused by an event of interest is detected at a plurality of detection points. Information about the sound is recorded. This information is dependent on a distance between the source position and the location of the detection point where the sound is received. The source position is approximated using the recorded information and the relative position of individual detection points relative to one another. The approximated source position is used as input for operating the electronic device.