Wireless communication system, wireless communication device and wireless communication method, and computer program
First Claim
1. A wireless communication system for performing information transmission with a predetermined transmission frame period, wherein:
- a first wireless unit transmits a ranging signal to a second wireless unit, said second wireless unit returns a response signal to said first wireless unit after a lapse of a predetermined period since said second wireless unit receives the ranging signal, and said first wireless unit measures a distance between said first wireless unit and said second wireless unit according to a propagation time between said first wireless unit and said wireless second unit, said propagation time being obtained from an elapsed time since said first wireless unit transmits the ranging signal.
1 Assignment
0 Petitions
Accused Products
Abstract
A wireless communication system of a simple configuration enabled to perform both data communication and accurate ranging. In the system, a second wireless unit receives a ranging signal after a lapse of a propagation time since a first wireless unit transmits the ranging signal. Then, after a delay of an image elimination period, the second wireless unit transmits a response signal. The first wireless unit receives the response signal after a lapse of a propagation time. Then, the first wireless unit obtains the propagation time, during which the signal propagates between the first and second wireless unit, according to an elapsed time since the ranging signal is transmitted. The distance therebetween is obtained by dividing the obtained propagation time by the velocity of light. Before the image elimination period elapses, in order to eliminate the physical reflection of radio waves, the first wireless unit is inhibited from opening a reception gate.
-
Citations
14 Claims
-
1. A wireless communication system for performing information transmission with a predetermined transmission frame period, wherein:
-
a first wireless unit transmits a ranging signal to a second wireless unit, said second wireless unit returns a response signal to said first wireless unit after a lapse of a predetermined period since said second wireless unit receives the ranging signal, and said first wireless unit measures a distance between said first wireless unit and said second wireless unit according to a propagation time between said first wireless unit and said wireless second unit, said propagation time being obtained from an elapsed time since said first wireless unit transmits the ranging signal.
-
-
2. A wireless communication system for performing information transmission with a predetermined transmission frame period, comprising:
-
ranging-signal transmission means for transmitting a ranging signal to a specific wireless unit in said wireless network;
response-signal reception means for receiving a response signal from said wireless unit after a lapse of a predetermined period since the ranging signal is transmitted; and
distance measurement means for measuring a distance therefrom to said wireless unit according to a propagation time obtained from an elapsed time from a moment, at which the ranging signal is transmitted, to a moment at which the response signal is received.
-
-
3. A wireless communication method for performing information transmission with a predetermined transmission frame period, comprising the steps of:
-
transmitting a ranging signal to a specific wireless unit in said wireless network;
receiving a response signal from said wireless unit after a lapse of a predetermined period since the ranging signal is transmitted; and
measuring a distance to said terminal according to a propagation time obtained from an elapsed time from a moment, at which the ranging signal is transmitted, to a moment at which the response signal is received. - View Dependent Claims (4, 5, 6)
-
-
7. A wireless communication device for performing information transmission with a predetermined transmission frame period, comprising:
-
ranging signal reception means for receiving a ranging signal from a wireless unit of a wireless network; and
response signal transmission means for transmitting a response signal after a lapse of a predetermined time since the ranging signal is received.
-
-
8. A wireless communication method for performing wireless communication in a wireless network, comprising the steps of:
-
receiving a ranging signal from a wireless unit of said wireless network; and
transmitting a response signal after a lapse of a predetermined time since the ranging signal is received. - View Dependent Claims (9, 10, 11, 12)
-
-
13. A computer program described in a computer-readable form in such a way as to execute an operation, which causes a wireless unit to perform information transmission with a predetermined transmission frame period, on a computer system, comprising the steps of:
-
transmitting a ranging signal to a specific wireless unit in said wireless network;
performing an operation of receiving a response signal from said wireless unit after a lapse of a predetermined period since the ranging signal is transmitted; and
measuring a distance to said terminal according to a propagation time obtained from an elapsed time from a moment, at which the ranging signal is transmitted, to a moment at which the response signal is received.
-
-
14. A computer program described in a computer-readable form in such a way as to execute an operation, which causes a wireless network to perform wireless communication, on a computer system, comprising the steps of:
-
receiving a ranging signal from a wireless unit of said wireless network; and
transmitting a response signal after a lapse of a predetermined time since the ranging signal is received.
-
Specification