US Patent 7929720 Position detecting system, speaker system, and user terminal apparatus

A position detecting system capable of detecting the position of a user as a listener in a simple manner. The position detecting system comprises a speaker system comprising a plurality of spatially-arranged speakers including at least a first speaker and a second speaker, a user terminal apparatus transmits a wireless signal to the speaker apparatus, and a position detecting apparatus which is provided in the side of the speaker apparatus. The position detecting apparatus computes the position of the user terminal apparatus based on a first time elapsed since the first speaker outputs a first measurement sound signal and until a receiving command transmitted by the user terminal apparatus in response to receiving the first measurement sound signal is received, and a second time elapsed since the second speaker outputs a second measurement sound signal and until a receiving command transmitted by the user terminal apparatus in response to receiving the second measurement sound signal is received.