Method for accessing hybrid network, and gateway apparatus, wireless terminal and communication system thereof

• US 20070098009A1
• Filed: 10/18/2006
• Published: 05/03/2007
• Est. Priority Date: 10/19/2005
• Status: Active Grant

• Current Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Original Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Inventors: Kayama, Hidetoshi, Du, Lei, Bai, Yong, Chen, Lan
• Granted Patent: US 8,160,048 B2
• Time in Patent Office: Days
• US Class Current: 370/445
• CPC Class Codes: H04W 48/12 using downlink control channel
• CPC Class Codes: H04W 48/14 using user query or user detection
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 84/042 Public Land Mobile systems, e.g. cellular systems
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 88/04 adapted for relaying to or from another terminal or user
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method for accessing a hybrid network including a wide area network and a distributed network, a gateway apparatus, a wireless terminal and a gateway communication system are disclosed for reducing the power consumption of the wireless terminal which is an access gateway. The method comprises: sensing by a gateway apparatus a relay request slot on a downlink common control channel of the wide area network; transmitting by a wireless terminal a relay request signal requesting to relay a data packet to be transmitted, in the relay request slot on the downlink common control channel; and if the relay request signal from the wireless terminal is sensed in the relay request slot, establishing by the gateway apparatus a connection with the wireless terminal in a distributed network environment. As such, the gateway apparatus accesses the wireless distributed network only when the surrounding wireless terminals require data relay, without sensing signals on both networks simultaneously, in order to reduce the power consumption.

Claims

1. A method for accessing a hybrid network including a wide area network and a distributed network, comprising

sensing, by a gateway apparatus, a relay request slot on a downlink common control channel of the wide area network;

transmitting, by a wireless terminal, a relay request signal requesting to relay a data packet to be transmitted, in the relay request slot on the downlink common control channel; and

establishing, by the gateway apparatus, a connection with the wireless terminal in the distributed network environment, if the relay request signal from the wireless terminal is sensed in the relay request slot.

2. The method according to claim 1, further comprising

transmitting, by the wireless terminal, a data packet to the gateway apparatus through the connection;

and

relaying, by the gateway apparatus, the data packet received from the wireless terminal to the wide area network.

3. The method according to claim 1 or 2, wherein establishing a connection with the wireless terminal comprises:

transmitting, by the gateway apparatus, a reply signal to the wireless terminal after receiving the relay request signal;

determining, by the wireless terminal, a gateway apparatus through which a relay operation is to be made by measuring channel conditions, and transmitting a selection signal containing an address of the gateway apparatus through which the relay operation is to be made; and

after receiving the selection signal, transmitting, by the gateway apparatus, corresponding to the address in the selection signal, a permit signal for permitting the wireless terminal to transmit a data packet to be relayed to the wireless terminal.

4. The method according to claim 3, wherein the gateway apparatus performs data packet transmissions with multiple wireless terminals around in a polling manner.

5. The method according to claim 3, wherein if the wireless terminal receives no reply signal in a predetermined time, then a contention window is enlarged and a random period is backed-off;

and the relay request signal is retransmitted on a relay request slot detected after the back-off time period.

6. The method according to claim 3, wherein the wireless terminal compares conditions of channels indicated in the reply signal, and selects a gateway apparatus having the best channel condition as the gateway apparatus through which the relay operation is to be made.

7. The method according to claim 6, wherein the wireless terminal selects a gateway apparatus that needs the lowest transmission power for directly communicating therewith as the gateway apparatus through which the relay operation is to be made.

8. The method according to claim 6, wherein the wireless terminal selects a gateway apparatus with the highest signal to interference and noise ratio as the gateway apparatus through which the relay operation is to be made.

9. The method according to claim 6, wherein the wireless terminal selects the nearest gateway apparatus as the gateway apparatus though which the relay operation is to be made.

10. The method according to claim 3, wherein once the gateway apparatus detects that a power level on the relay request slot is larger than a noise power, the gateway apparatus transmits the reply signal in the distributed network environment.

11. The method according to claim 3, wherein once the gateway apparatus detects a high level on the relay request slot, the gateway apparatus transmits the reply signal in the distributed network environment.

12. The method according to claim 3, wherein after successfully receiving the data packet to be relayed, the gateway apparatus transmits an acknowledgement signal to the wireless terminal.

13. The method according to claim 3, wherein the downlink common control channel is a broadcast channel.

14. A gateway apparatus for accessing a hybrid network including a wide area network and a distributed network, comprising:

a wide area network transceiving means for transmitting and receiving signals in the wide area network;

a distributed network transceiving means for transmitting and receiving signals in the distributed network;

a detection means for detecting the signals received by the wide area network transceiving means on a downlink common control channel of the wide area network, and for detecting the type of current slot on the downlink common control channel; and

an access determination means for receiving results of the detection from the detection means and determining a network to be accessed currently.

15. The gateway apparatus according to claim 14, further comprising:

a transmission control means for receiving results from the access determination means and the detection means, and for controlling transmission and reception of signals in the distributed network; and

a delay means for receiving an instruction from the transmission control means and delaying.

16. The gateway apparatus according to claim 14 or 15, further comprising:

a transmission storage means for storing packets to be transmitted.

17. The gateway apparatus according to claim 14, 15 or 16, wherein if the detection means detects a relay request slot on the downlink common control channel and detects a relay request signal requesting to relay a data packet to be transmitted from a wireless terminal in the relay request slot, the access determination means determines to access the distributed network.

18. The gateway apparatus according to claim 17, wherein after the relay request signal is received, a reply signal is transmitted to the wireless terminal through the distributed network transceiving means, and after a selection signal containing an address of the gateway apparatus is received from the wireless terminal, a permit signal for permitting the wireless terminal to transmit a data packet to be relayed is transmitted to the wireless terminal.

19. The gateway apparatus according to claim 18, wherein the gateway apparatus performs data packet transmissions with multiple wireless terminals around in a polling manner.

20. The gateway apparatus according to claim 18, wherein after receiving the relay request signal, the transmission control means instructs the delay means to delay a random period for performing a back-off operation, and after backing-off the period, the reply signal is transmitted by the distributed network transceiving means.

21. The gateway apparatus according to claim 17, wherein once the detection means detects a high level in the relay request slot, a reply signal is transmitted to the wireless terminal.

22. The gateway apparatus according to claim 17, wherein once the detection means detects a power level on the relay request slot is larger than a noise power, a reply signal is transmitted in the distributed network environment.

23. The gateway apparatus according to claim 17, wherein when the signals received by the distributed network transceiving means indicate that a data packet is received, the transmission control means instructs the distributed network transceiving means to transmit an acknowledgement signal.

24. The gateway apparatus according to claim 17, wherein the downlink common control channel is a broadcast channel.

25. The gateway apparatus according to claim 14, wherein the wide area network transceiving means comprises:

a wide area network transmission means for transmitting signals in the wide area network; and

a wide area network reception means for receiving signals from the wide area network.

26. The gateway apparatus according to claim 14, wherein the distributed network transceiving means comprises:

a distributed network transmission means for transmitting signals in the distributed network; and

a distributed network reception means for receiving signals from the distributed network.

27. A communication system including the gateway apparatus according to claim 14.

28. A wireless terminal to perform communication through a relay of a gateway apparatus in a hybrid network including a wide area network and a distributed network, the wireless terminal comprising:

a distributed network transceiving means for transmitting and receiving signals in the distributed network;

a downlink common control channel transceiving means for transmitting a relay request signal requesting to relay a data packet to be transmitted and receiving signals on a downlink common control channel of the wide area network;

a detection means for detecting the signals received by the downlink common control channel transceiving means on the downlink common control channel, and for detecting the type of current slot on the downlink common control channel; and

an access determination means for receiving information from the detection means and determining a network to be accessed currently.

29. The wireless terminal according to claim 28, further comprising:

a transmission storage means for storing packets to be transmitted;

a transmission control means for receiving results from the access determination means and the detection means, for controlling transmission and reception of signals the distributed network, and for clocking; and

a delay means for receiving an instruction from the transmission control means and delaying.

30. The wireless terminal according to claim 28 or 29, wherein

when a packet to be transmitted is stored in the transmission control means of the wireless terminal, the access determination means operates to access the downlink common control channel, and the relay request signal is transmitted on the relay request slot detected by the detection means through the downlink common control channel transceiving means.

31. The wireless terminal according to claim 30, wherein after the transmission of the relay request signal is completed, the access determination means operates to access the distributed network and enables the transmission control means.

32. The wireless terminal according to claim 28 or 29, wherein when the access determination means operates to access the distributed network, the transmission control means begins clocking, and signal is received by the distributed network transceiving means within a reception threshold time;

when the reception threshold time is reached, if a reply signal is correctly received, the distributed network transceiving means is instructed to transmit a selection signal containing an address of an gateway apparatus through which the relay operation is to be made.

33. The wireless terminal according to claim 32, wherein if no packet is received, then the delay means is enabled for backing-off a random period.

34. The wireless terminal according to claim 32, wherein when the distributed network transceiving means receives a permit signal for permitting a transmission of a data packet to be relayed, the data packet is transmitted;

and when the distributed network transceiving means successfully receives an acknowledgement signal, the access determination means is instructed to stop accessing the distributed network.

35. The wireless terminal according to claim 32, wherein the transmission control means compares conditions of channels indicated in the reply signal, and selects a gateway apparatus with the best condition of channel as the gateway apparatus through which the relay operation is to be made.

36. The wireless terminal according to claim 35, wherein the transmission control means selects a gateway apparatus that needs the lowest transmission power for directly communicating with the wireless terminal as the gateway apparatus through which the relay operation is to be made.

37. The wireless terminal according to claim 35, wherein the transmission control means selects a gateway apparatus with the highest signal to interference and noise ratio as the gateway apparatus through which the relay operation is to be made.

38. The wireless terminal according to claim 35, wherein the transmission control means selects the nearest gateway apparatus as the gateway apparatus through which the relay operation is to be made.

39. The wireless terminal according to claim 30, wherein the downlink common control channel is a broadcast channel.

40. The wireless terminal according to claim 28, wherein the distributed network transceiving means comprises:

a distributed network transmission means for transmitting signals in the distributed network; and

a distributed network reception means for receiving signals from the distributed network.

41. The wireless terminal according to claim 28, wherein the downlink common control channel transceiving means comprises:

a downlink common control channel transmission means for transmitting a relay request signal on the downlink common control channel of the wide area network; and

a downlink common control channel reception means for receiving signals on the downlink common control channel of the wide area network.

42. A communication system including the wireless terminal according to claim 28.

43. A method for accessing a hybrid network including a wide area network and a distributed network, comprising

regularly transmitting, by a base station of the wide area network, a synchronization signaling for synchronizing with a downlink common control channel, on a transmission frequency band of the wireless distributed network;

transmitting, by a wireless terminal, a relay request signal requesting to relay a data packet to be transmitted, after receiving the synchronization signaling;

starting, by a gateway apparatus, to access the distributed network to receive the relay request signal from the wireless terminal at a time instant corresponding to the synchronization signaling sensed on the downlink common control channel; and

establishing, by the gateway apparatus, a connection with the wireless terminal in the distributed network environment.

44. The method according to claim 43, further comprising

transmitting, by the wireless terminal, a data packet to the gateway apparatus through the connection;

and

relaying, by the gateway apparatus, the data packet received from the wireless terminal to the wide area network.

45. The method according to claim 43 or 44, wherein establishing a connection with the wireless terminal comprises:

transmitting, by the gateway apparatus, a reply signal to the wireless terminal after receiving the relay request signal;

determining, by the wireless terminal, a gateway apparatus through which a relay operation is to be made by measuring channel conditions, and transmitting a selection signal containing an address of the gateway apparatus through which the relay operation is to be made; and

after receiving the selection signal, transmitting a permit signal, by the gateway apparatus, corresponding to the address included in the selection signal.

46. The method according to claim 45, wherein the gateway apparatus performs data packet transmissions with multiple wireless terminals around in a polling manner.

47. The method according to claim 45, wherein if the wireless terminal receives no reply signal in a predetermined time, then a contention window is enlarged and a random period is backed-off;

and the relay request signal is retransmitted on a relay request slot detected after the back-off time period.

48. The method according to claim 45, wherein the wireless terminal compares conditions of channels indicated in the reply signal and selects a gateway apparatus with the best condition of channel as the gateway apparatus through which the relay operation is to be made.

49. The method according to claim 48, wherein the wireless terminal selects a gateway apparatus that needs the lowest transmission power for directly communicating therewith as the gateway apparatus through which the relay operation is to be made.

50. The method according to claim 48, wherein the wireless terminal selects a gateway apparatus with the highest signal to interference and noise ratio as the gateway apparatus through which the relay operation is to be made.

51. The method according to claim 48, wherein the wireless terminal selects the nearest gateway apparatus as the gateway apparatus through which the relay is to be made.

52. The method according to claim 45, wherein once the gateway apparatus detects that a power level in a sensed time interval is larger than a noise power, the gateway apparatus transmits the reply signal in the distributed network environment.

53. The method according to claim 45, wherein once the gateway apparatus detects a high level in a sensed time interval, the gateway apparatus transmits the reply signal to the wireless terminal.

54. The method according to claim 45, wherein after successfully receiving the data packet to be relayed, the gateway apparatus transmits an acknowledgement signal to the wireless terminal.

55. The method according to claim 45, wherein the downlink common control channel is a broadcast channel.

56. A gateway apparatus for accessing a hybrid network including a wide area network and a distributed network, comprising:

a wide area network transceiving means for transmitting and receiving signals in the wide area network;

a distributed network transceiving means for transmitting and receiving signals in the distributed network;

a timer means for detecting whether current time is an integer multiple of a periodic time, and periodically enabling a sensing unit to sense a channel of the distributed network; and

the sensing means for sensing the channel of the distributed network at the enabling time instant instructed by the timer means.

57. The gateway apparatus according to claim 56, further comprising:

a transmission control means for controlling transmission and reception of the distributed network according to information received from the sensing means; and

a delay means for receiving an instruction from the transmission control means and delaying.

58. The gateway apparatus according to claim 57, further comprising:

a transmission storage means for storing packets to be transmitted.

59. The gateway apparatus according to claim 57, wherein when the sensing means detects that there is a data transmission in the wireless distributed network in a sensed time interval, the transmission control means is instructed to communicate with surrounding wireless terminals in the wireless distributed network.

60. The gateway apparatus according to claim 59, wherein after a relay request signal requesting to relay a data packet to be transmitted by the wireless terminal is received, a reply signal is transmitted to the wireless terminal by the distributed network transceiving means, and after a selection signal containing an address of the gateway apparatus is received the wireless terminal, a permit signal for permitting the wireless terminal to transmit a data packet to be relayed is transmitted to the wireless terminal.

61. The gateway apparatus according to claim 60, wherein the gateway apparatus performs data packet transmissions with multiple wireless terminals around in a polling manner.

62. The gateway apparatus according to claim 59, wherein if the sensing means detects a power level larger than a noise level at a time instant corresponding to the synchronization signaling on the downlink common control channel within the sensed time interval, the delay means is instructed to delay a random period for performing a back-off operation, and after backing-off the period, a reply signal is transmitted in the distributed network environment.

63. The gateway apparatus according to claim 62, wherein once the sensing means detects a high level in the sensed time interval, it transmits the reply signal to the wireless terminal.

64. The gateway apparatus according to claim 59, wherein when the signals received by the distributed network transceiving means indicate that a data packet is received, the transmission control means instructs the distributed network transceiving means to transmit an acknowledgement signal.

65. The gateway apparatus according to claim 59, wherein the downlink common control channel is a broadcast channel.

66. The gateway apparatus according to claim 56, wherein the wide area network transceiving means comprises:

a wide area network transmission means for transmitting signals in the wide area network; and

a wide area network reception means for receiving signals from the wide area network.

67. The gateway apparatus according to claim 56, wherein the distributed network transceiving means comprises:

a distributed network transmission means for transmitting signals in the distributed network; and

a distributed network reception means for receiving signals from the distributed network.

68. A communication system including the gateway apparatus according to claim 56.

69. A wireless terminal to perform communication through a relay of a gateway apparatus in a hybrid network including a wide area network and a distributed network, the wireless terminal comprising:

a distributed network transceiving means for transmitting and receiving signals in the distributed network;

a transmission control means for controlling transmission and reception of signals in the distributed network, and clocking; and

a delay means for receiving an instruction from the transmission control means and delaying.

70. The wireless terminal according to claim 69, further comprising:

a transmission storage means for storing packets to be transmitted.

71. The wireless terminal according to claim 70, wherein if there is a packet to be transmitted in the transmission control means, and when the distributed network transceiving means receives a synchronization signaling for synchronizing with a downlink common control channel regularly transmitted on a transmission frequency band of the wireless distributed network by a base station of the wide area network, the transmission control means orders the distributed network transceiving means to transmit a relay request signal requesting to relay a data packet to be transmitted by the wireless terminal after receiving the synchronization signaling.

72. The wireless terminal according to claim 71, wherein

when receiving a reply signal from a gateway apparatus, the wireless terminal determines a gateway apparatus through which a relay operation is to be made by measuring channel conditions, and transmits a selection signal containing an address of the gateway apparatus through which the relay operation is to be made;

and

after receiving the selection signal, the gateway apparatus corresponding to the address in the selection signal transmits a permit signal for permitting the wireless terminal to transmit a data packet to be relayed to the wireless terminal.

73. The wireless terminal according to claim 71, wherein if the distributed network transceiving means receives no reply signal in a reception threshold time, then the delay means is enabled to enlarge a contention window and back-off a random period;

and the relay request signal is retransmitted after detecting the synchronization signal after the ending of the back-off time period.

74. The wireless terminal according to claim 71, wherein the transmission control means compares conditions of channels indicated in the reply signal, and selects a gateway apparatus with the best channel condition as the gateway apparatus through which the relay operation is to be made.

75. The wireless terminal according to claim 74, wherein the transmission control means selects a gateway apparatus that needs the lowest transmission power for directly communicating with the wireless terminal as the gateway apparatus through which the relay operation is to be made.

76. The wireless terminal according to claim 74, wherein the transmission control means selects a gateway apparatus with the highest signal to interference noise ratio as the gateway apparatus through which the relay operation is to be made.

77. The wireless terminal according to claim 74, wherein the transmission control means selects the nearest gateway apparatus as the gateway apparatus through which the relay operation is to be made.

78. The wireless terminal according to claim 69, wherein the downlink common control channel is a broadcast channel.

79. The wireless terminal according to claim 69, wherein the distributed network transceiving means comprises:

a distributed network transmission means for transmitting signals in the distributed network; and

a distributed network reception means for receiving signals from the distributed network.

80. A communication system including the wireless terminal according to claim 69.