To measure a distance between two transceivers by a simplified structure.
A transmission signal S5 including a first state A and a second state B in which a frequency or a phase of carrier waves is changed every half cycle of a first reference signal S1 based on the first reference signal is transmitted from a first transceiver to a second transceiver. The second transceiver demodulates the receiving signal from the first transceiver to detect the first state and the second state. During a period of a half cycle in which reception periods of the first and second states are equal, return carrier waves of a predetermined frequency are transmitted to the first transceiver. The first transceiver demodulates the transmission signal S5 by the return carrier waves S6 received from the second transceiver, and a distance is obtained based on a length of at least one of periods with two different states relating to the frequency or the phase of the demodulated signal.
TAKAHARA NORIMITSU
SUDA SATORU
TOYOTA IND CORP
| JP2008122255A | 2008-05-29 | |||
| JP2009168719A | 2009-07-30 | |||
| JP2008304192A | 2008-12-18 | |||
| JP2008032535A | 2008-02-14 |
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