Electronic device, method for controlling electronic device, and program

An electronic device comprising:

• a plurality of sensors configured to receive a sound wave or an ultrasonic wave from a sound source;
• and
• a signal processing unit configured to detect an object with a subspace method, based on a reception signal received as the sound wave or the ultrasonic wave, wherein
• the signal processing unit is configured to estimate a direction of arrival of the sound wave or the ultrasonic wave, based on solutions of an algebraic equation Root-MUSIC Polynomial (hereinafter referred to as “RMP solutions”) in a Root-MUSIC method that satisfy a first requirement and a second requirement in terms of positions of the RMP solutions in a complex plane,
• the first requirement being a requirement related to a distance between a unit circle and each of the RMP solutions in the complex plane,
• the second requirement being a requirement related to a distance or an argument between at least two adjacent RMP solutions among the RMP solutions in the complex plane, and the second requirement is determined by calculating a difference between norms of the at least two adjacent RMP solutions or by calculating a difference between arguments of the at least two adjacent RMP solutions.

A method for controlling an electronic device, the method comprising:

• a step of transmitting a transmission wave with a transmission antenna;
• a step of receiving, with a plurality of reception antennas, a reflected wave that is the transmission wave having been reflected;
• a step of detecting an object with a subspace method, based on a transmission signal transmitted as the transmission wave and a reception signal received as the reflected wave;
• and
• a step of estimating a direction of arrival of the reflected wave, based on solutions of an algebraic equation Root-MUSIC Polynomial (hereinafter referred to as “RMP solutions”) in a Root-MUSIC method that satisfy a first requirement and a second requirement in terms of positions of the RMP solutions in a complex plane,
• the first requirement being a requirement related to a distance between a unit circle and each of the RMP solutions in the complex plane,
• the second requirement being a requirement related to a distance or an argument between at least two adjacent RMP solutions among the RMP solutions in the complex plane, and the second requirement is determined by calculating a difference between norms of the at least two adjacent RMP solutions or by calculating a difference between arguments of the at least two adjacent RMP solutions.

A non-transitory computer-readable recording medium storing computer program instructions, which when executed by a computer, cause the computer to:

• transmit a transmission wave with a transmission antenna;
• receive, with a plurality of reception antennas, a reflected wave that is the transmission wave having been reflected;
• detect an object with a subspace method, based on a transmission signal transmitted as the transmission wave and a reception signal received as the reflected wave;
• and
• estimate a direction of arrival of the reflected wave, based on solutions of an algebraic equation Root-MUSIC Polynomial (hereinafter referred to as “RMP solutions”) in a Root-MUSIC method that satisfy a first requirement and a second requirement in terms of positions of the RMP solutions in a complex plane,
• the first requirement being a requirement related to a distance between a unit circle and each of the RMP solutions in the complex plane,
• the second requirement being a requirement related to a distance or an argument between at least two adjacent RMP solutions among the RMP solutions in the complex plane, and the second requirement is determined by calculating a difference between norms of the at least two adjacent RMP solutions or by calculating a difference between arguments of the at least two adjacent RMP solutions.

An electronic device comprising:

• a transmission antenna configured to transmit a transmission wave;
• a plurality of reception antennas configured to receive a reflected wave that is the transmission wave having been reflected;
• a signal processing unit configured to detect an object with a subspace method, based on a transmission signal transmitted as the transmission wave and a reception signal received as the reflected wave;
• and
• a display unit configured to display an image, wherein
• the signal processing unit is configured to estimate a direction of arrival of the reflected wave by removing a first solution not satisfying a requirement related to a distance or an argument between the first solution and at least one second solution adjacent to the first solution in a complex plane, and the signal processing unit is configured to determine whether the first solution satisfies the requirement by calculating a difference between norms of the first solution and the at least one second solution or by calculating a difference between arguments of the first solution and the at least one second solution, and
• the display unit is configured to display the estimated direction of arrival.