Relay apparatus, communication terminal, communication system, and semiconductor integrated circuit
AssigneePanasonic Corporation
InventorsYuki Nishio, Masataka Irie
Life of this patent
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Abstract
The present invention relates to a wireless LAN (Local Area Network) communication system. Upon a timer unit 108 clocking a predetermined time T after an access point 100 has transmitted a beacon signal 200, a transmission frame control unit 105 generates a CTS frame 301, and transmits an error frame 401 via a transmission frame generation unit 106, a wireless transmission unit 107 and an antenna 109. Accordingly, upon receiving the CTS frame 301, a communication terminal 20 ceases transmitting data for a NAV (Network Allocation Vector, transmission prohibition interval) period in accordance with IEEE 802.11 standard.
Claims15
A relay apparatus that relays communication between a plurality of communication terminals in accordance with access control by CSMA/CA method, the relay apparatus comprising:
- a transmission unit operable to transmit, to the plurality of communication terminals, a beacon signal at a predetermined time interval Tb, and a predetermined signal for causing the plurality of communication terminals to cease signal transmission for a predetermined time period t;
- and
- a control unit operable to control the transmission unit to transmit the predetermined signal upon elapse of a predetermined time period T after transmission of the beacon signal, the predetermined time period T satisfying Tb−t<T<Tb.
A relay apparatus that, in accordance with access control by CSMA/CA method, mediates communication between a plurality of communication terminals, the relay apparatus and the plurality of communication terminals ceasing signal transmission for a predetermined time period t upon receiving a signal, the relay apparatus comprising:
- a transmission unit operable to transmit a signal to the plurality of communication terminals;
- and
- a control unit operable to control the transmission unit to, exclusively in a case of transmitting a beacon signal, perform transmission regardless of the predetermined time period t.
A communication system including a plurality of communication terminals and a relay apparatus that, in accordance with access control by CSMA/CA method in compliance with IEEE 802.11 standard, relays communication between the plurality of communication terminals, the plurality of communication terminals and the relay apparatus ceasing signal transmission for a predetermined time period t upon receiving a signal,
- the relay apparatus comprising:
- a reception unit operable to receive a clear to send (CTS) frame;
- a transmission unit operable to transmit, to the plurality of communication terminals, a beacon signal at a predetermined time interval Tb, and an read to send (RTS) frame;
- and
- a control unit operable to control the transmission unit to transmit the read to send (RTS) frame upon elapse of a predetermined time period T after transmission of the beacon signal, the predetermined time period T satisfying Tb−t<T<Tb, and
- each of the communication terminals comprising:
- a reception unit operable to receive the read to send (RTS) frame and the clear to send (CTS) frame;
- a transmission unit operable to, upon reception of the read to send (RTS) frame, transmit a clear to send (CTS) frame in response thereto to the relay apparatus and the other one or more of the communication terminals;
- and
- a control unit operable to control the transmission unit of the communication terminal to, upon reception of the clear to send (CTS) frame, cease signal transmission for a period indicated by a network allocation vector (NAV) included in the received clear to send (CTS) frame.
A communication terminal that performs communication with another communication terminal via a relay apparatus in accordance with access control by CSMA/CA method, the communication terminal comprising:
- a reception unit operable to receive a beacon signal from the relay apparatus at a predetermined time interval Tb, and a predetermined signal for ceasing signal transmission for a predetermined time period t;
- a transmission unit operable to transmit the predetermined signal to the relay apparatus and the another communication terminal upon elapse of a predetermined time period T after reception of the beacon signal, the predetermined time period T satisfying Tb−t<T<Tb;
- and
- a control unit operable to control the transmission unit to, upon reception of the predetermined signal, cease signal transmission for the predetermined time period t.
A semiconductor integrated circuit comprising:
- a transmission unit operable to transmit, to an external device, a beacon signal at a predetermined time interval Tb, and a predetermined signal for causing the external device to cease signal transmission for a predetermined time period t;
- and
- a control unit operable to control the transmission unit to transmit the predetermined signal upon elapse of a predetermined time period T after transmission of the beacon signal, the predetermined time period T satisfying Tb−t<T<Tb.
A semiconductor integrated circuit comprising:
- a reception unit operable to receive a beacon signal from an external device at a predetermined time interval Tb, and a predetermined signal for ceasing signal transmission for a predetermined time period t;
- a transmission unit operable to transmit the predetermined signal to the external device upon elapse of a predetermined time period T after reception of the beacon signal, the predetermined time period T satisfying Tb−t<T<Tb;
- and
- a control unit operable to control the transmission unit to, upon reception of the predetermined signal, cease signal transmission for the predetermined time period t.
Dependencies are inferred from the claim text.