VEHICLE COMMUNICATION SYSTEM, IN-VEHICLE DEVICE, PORTABLE DEVICE, AND COMPUTER PROGRAM

摘要

Provided are: a vehicle communication system with which it is possible to accurately determine whether a portable device is inside or outside a vehicle cabin even when some of a plurality of in-vehicle antennas provided in a vehicle are defective; an in-vehicle device and a portable device constituting the vehicle communication system; and a computer program. In the vehicle communication system provided with the in-vehicle device for transmitting and receiving signals using the plurality of antennas, which are provided in different positions in the vehicle, and the portable device for transmitting and receiving the signals using the in-vehicle device and the antennas, the in-vehicle device: stores multiple types of statistical values that are obtained by having the reception signal strength of signals transmitted by some of the antennas be measured, in advance, inside and outside the vehicle cabin, the statistical values being classified in relation to whether they were obtained inside or outside the vehicle; detects a defective antenna; calculates, for inside and outside the vehicle cabin, the statistical distance between the measured reception signal strength and the statistical value of a group corresponding to the antennas being used based on the other antennas besides the defective antenna; makes a comparison between the results of the calculation; and determines whether the portable device is inside or outside the vehicle cabin.