| 摘要 |
PROBLEM TO BE SOLVED: To provide a distance calculation system, communication equipment, a keyless entry device, and a distance calculation method capable of accurately calculating a distance.SOLUTION: A distance calculation system includes: on-vehicle communication equipment 200 including a transmission module 210 having a transmission clock signal generation part 232, a modulation part 231 for generating a transmission signal as an electric signal on the basis of a transmission clock signal, and an LF transmission antenna 220 with a predetermined tuning frequency for transmitting an LF transmission signal, and a measurement clock signal generation part 260 for generating a measurement clock signal; portable communication equipment 300 including a portable reception part 320 for receiving the LF transmission signal and a detection part 331 for detecting the reception intensity of the LF transmission signal; an error acquisition part 272 for acquiring information on an error on the basis of the measurement clock signal; and a distance calculation part 273 for calculating a distance between the on-vehicle communication equipment 200 and the portable communication equipment 300 in which the influence of the error has been corrected on the basis of the information on the error and the reception intensity.SELECTED DRAWING: Figure 1 |
