Hybrid wireless communication system and communication method using the same

• US 8,126,472 B2
• Filed: 09/08/2006
• Issued: 02/28/2012
• Est. Priority Date: 09/08/2005
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd., University of Edinburgh
• Original Assignee: Samsung Electronics Co. Ltd., The University Court of the University of Aberdeen
• Inventors: Lee, Yeon-Woo, Yun, Sang-Boh, Haas, Harald, McLaughlin, Stephen, Hassan, Khaled S.
• Primary Examiner(s): Corsaro, Nick
• Assistant Examiner(s): NGO, CHUONG A
• Application Number:
  US11/517,784
• Publication Number:
  US 20070121531A1
• Time in Patent Office: 1,999 Days
• Field of Search: 370/281, 370/328, 370/330, 370/331, 370/509, 370/581, 370/478, 455/77, 455/103, 455/450
• US Class Current: 455/451
• CPC Class Codes: H04B 7/2615 using hybrid frequency-time division multiple access [FDMA-TDMA]
• CPC Class Codes: H04L 1/0018 based on latency requirement
• CPC Class Codes: H04L 2001/0097 Relays
• CPC Class Codes: H04W 72/00 Local resource management
• 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 88/10 adapted for operation in multiple networks, e.g. multi-mode access points

Abstract

Disclosed is a hybrid wireless communication system and a communication method in the system. The system supports time and frequency division duplexing modes and includes a base station having a cellular communication range based on a cellular mode and mobile stations within the cellular communication range. The base station divides each available frequency resource into frames for communication, and each frame switches between a real-time service mode and a non-real-time service mode at a switching time within the frame. Communication is performed with the mobile stations within the cellular communication range via at least one of an uplink and a downlink in the real-time service mode of each frame according to the frequency division duplexing mode. Communication is performed with the mobile stations via the uplink and the downlink in the non-real-time service mode of each frame according to an ad hoc mode based on the time division duplexing mode.

Claims

1. A hybrid wireless communication system supporting a time division duplexing (TDD) mode and a frequency division duplexing (FDD) mode, the system comprising:

a base station having a cellular communication range based on a cellular mode;

the base station determining a location of a switching time of each frame based on the amount of traffic necessary for each of a real-time service and non-real-time service; and

a plurality of mobile stations within the cellular communication range,

wherein the base station is configured to divide each available frequency resource into frames for communication, each frame switches between a real-time service mode and a non-real-time service mode at the switching time within the frame, communication is performed with the plurality of mobile stations via an uplink and a downlink in the real-time service mode of each frame according to the cellular mode based on the FDD mode, and communication is performed with the plurality of mobile stations via the uplink and the downlink in the non-real-time service mode of each frame according to an ad hoc mode based on the TDD mode, and

wherein the base station is configured to vary the location of the switching time of each frame based on the amount of traffic necessary for each of a real-time service and a non-real-time service, the base station communicates directly with a target mobile station in the FDD mode and the base station communicates with the target mobile station via at least one relay node in the TDD mode, time slots of the uplink and the downlink have an asymmetric ratio or a symmetric ratio depending on the amount of traffic necessary for each of the uplink and the downlink and the base station broadcasts the switching time to each of the plurality of mobile stations.

2. The system as claimed in claim 1, wherein the base station designates one of the plurality of mobile stations spaced a predetermined distance from the base station as a gateway of a satellite cell in the non-real-time service mode and, after data is transmitted to the gateway, the base station functions as a gateway in the ad hoc mode with regard to mobile stations in a selected range adjacent to the base station.

3. The system as claimed in claim 1, wherein, when communication is performed in the ad hoc mode, satellite cells are constructed according to a distance from the base station to the plurality of mobile stations, a degree of closeness among the plurality of mobile stations, and a positional relationship among closely located mobile stations, and an identical frequency resource is allocated to the constructed satellite cells, a hop distance between the satellite cells being at least 2.

4. The system as claimed in claim 3, wherein a time slot is allocated to the satellite cells, the identical frequency resource having been allocated to the satellite cells, in a symmetric resource allocation method.

5. A communication method of a base station in a hybrid wireless communication system supporting a time division duplexing (TDD) mode and a frequency division duplexing (FDD) mode, the method comprising the steps of:

dividing each available frequency resource into frames;

determining a location of a switching time of each frame based on the amount of traffic necessary for each of a real-time service and a non-real-time service;

setting each frame so that the frame switches between a real-time service mode and a non-real-time service mode at the switching time within the frame;

communicating with a plurality of mobile stations within a cellular communication range, based on a cellular mode, of the base station via an uplink and a downlink in the real-time service mode of each frame according to the cellular mode based on the FDD mode; and

communicating with the plurality of mobile stations via the uplink and the downlink in the non-real-time service mode of each frame according to an ad hoc mode based on the TDD mode,

wherein the location of the switching time of each frame is varied based on the amount of traffic necessary for each of the real-time service and the non-real-time service, the base station communicates directly with a target mobile station in the FDD mode and the base station communicates with the target mobile station via at least one relay node in the TDD mode, time slots of the uplink and the downlink have an asymmetric ratio or a symmetric ratio depending on the amount of traffic necessary for each of the uplink and the downlink and the base station broadcasts the switching time to each of the plurality of mobile stations.

6. The method as claimed in claim 5, further comprising:

designating one of the plurality of mobile stations spaced a predetermined distance from the base station as a gateway of a satellite cell in the non-real-time service mode; and

operating the base station as a gateway in the ad hoc mode with regard to mobile stations in a selected range adjacent to the base station after data is transmitted to the gateway of the satellite cell in the non-real-time service mode.

7. The method as claimed in claim 5, wherein, when communication is performed in the ad hoc mode, satellite cells are constructed according to a distance from the base station to the plurality of mobile stations, a degree of closeness among the plurality of mobile stations, and a positional relationship among closely located mobile stations, and an identical frequency resource is allocated to the constructed satellite cells, a hop distance between the satellite cells being at least 2.

8. The method as claimed in claim 7, wherein a time slot is allocated to the satellite cells, the identical frequency resource having been allocated to the satellite cells, in a symmetric resource allocation method.

9. A communication method of a mobile station in a hybrid wireless communication system supporting a time division duplexing (TDD) mode and a frequency division duplexing (FDD) mode, the method comprising the steps of:

communicating with a base station having a cellular communication range based on a cellular mode via an uplink and a downlink in a real-time service mode according to the cellular mode based on the FDD mode, on a first part of a frame;

acquiring a location of a switching time of each frame determined based on the amount of traffic necessary for each of a real-time service and a non-real-time service; and

communicating with the base station via the uplink and the downlink in a non-real-time service mode according to an ad hoc mode based on the TDD mode, on another part of the frame separated from the first part of the frame by a switching time,

wherein the location of the switching time of the frame is varied based on the amount of traffic necessary for each of the real-time service and the non-real-time service, the base station communicates directly with a target mobile station in the FDD mode and the base station communicates with the target mobile station via at least one relay node in the TDD mode, time slots of the uplink and the downlink have an asymmetric ratio or a symmetric ratio depending on the amount of traffic necessary for each of the uplink and the downlink and the base station broadcasts the switching time to each of all mobile stations within the cellular communication range.

10. The method as claimed in claim 9, wherein one of a plurality of mobile stations spaced a predetermined distance from the base station is designated as a gateway of a satellite cell in the non-real-time service mode, and the base station is operated as a gateway in the ad hoc mode with regard to mobile stations in a selected range adjacent to the base station after data is transmitted to the gateway of the satellite cell in the non-real-time service mode.

11. The method as claimed in claim 9, wherein, when communication is performed in the ad hoc mode, satellite cells are constructed according to a distance from the base station to the plurality of mobile stations, a degree of closeness among the plurality of mobile stations, and a positional relationship among closely located mobile stations, and an identical frequency resource is allocated to the constructed satellite cells, a hop distance between the satellite cells being at least 2.

12. The method as claimed in claim 11, wherein a time slot is allocated to the satellite cells, the identical frequency resource having been allocated to the satellite cells, in a symmetric resource allocation method.