Patent ID: 8872620
Filing Date: 2014-10-28
Classification: B60R,G01S,H04B

Abstract:
1. A wireless key system to perform wireless communication between a wireless key movable separately from a main body and a communication device mounted in the main body to thereby determine whether the wireless key has moved from a location outside of the main body to a location inside of the main body, wherein the communication device comprises a component which continuously or intermittently transmits a wireless signal through both an inner antenna provided inside the main body and an outer antenna provided outside the main body, the outer antenna having a directivity different from that of the inner antenna, and the wireless key comprises: a memory component; a plurality of antennas, each respective antenna having a different directivity from one another, and configured to receive the wireless signal transmitted from the communication device; a determination component which determines, at a first point in time, whether the wireless signal has been received by any one of the plurality of antennas; a measuring component which measures a direction of movement of the wireless key when receipt of the wireless signal has been determined by the determination component; a detecting component which detects which of the plurality of antennas that has received the wireless signal at the first point in time at a highest signal level, and stores that respective antenna as a first antenna in the memory component as information; a selecting component which selects one antenna of the plurality of antennas that has the same directivity as the inner antenna as a second antenna according to the direction of movement measured by the measuring component and the information specifying the first antenna detected by the detecting component; and a deciding component which decides that the wireless key is located at the location inside of the main body when a signal level of the wireless signal received by the second antenna at a subsequent point in time after the first point in time is greater than the signal level of the wireless signal received by the first antenna at the first point in time.