Link and radio cell adaptation in TDD systems

• US 6,807,154 B1
• Filed: 10/11/1999
• Issued: 10/19/2004
• Est. Priority Date: 10/12/1998
• Status: Expired due to Term

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Dettmar, Uwe, Li, Hui, Wachsmann, Udo, Schramm, Peter, Thielecke, Jörn, Malmgren, Göran, Khun-Jush, Jamshid
• Primary Examiner(s): Kizou, Hassan
• Assistant Examiner(s): LEE, TIMOTHY L
• Application Number:
  US09/415,705
• Time in Patent Office: 1,835 Days
• Field of Search: 370/252, 370/276, 370/277, 370/278, 370/280, 370/282, 370/345, 370/347, 370/328, 370/329, 370/336, 370/337, 370/468, 370/281, 370/294, 370/312, 370/314, 370/442, 370/465, 370/498, 370/545
• US Class Current: 370/252
• CPC Class Codes: H04L 1/0001 Systems modifying transmission characteristics according to link quality, e.g. power backoff adaptive data allocation for multicarrier modulation H04L5/0044; controlling transmission power for radio systems H04W52/04
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0009 by adapting the channel coding H04L1/1812 takes precedence
• CPC Class Codes: H04L 1/0025 Transmission of mode-switching indication
• CPC Class Codes: H04W 48/12 using downlink control channel
• CPC Class Codes: H04W 8/245 from a network towards a terminal

Abstract

A TDMA/TDD link adaptation method determines radio link quality at a base station. The radio link quality is used to update and broadcast a physical layer parameter indicator (10-16) from the base station on a broadcast control channel having a common physical layer parameter indicator for all uplink and downlink channels.

Claims

1. A TDMA/TDD media access control frame structure encoded in a computer-readable medium, said control frame structure comprising:

a broadcast message having a common dynamically updated physical layer parameter indicator for a plurality of uplink channels, said common dynamically updated physical layer parameter indicator for indicating a decision relating to a chosen transmission/reception mode for performing radio cell adaptation on said associated uplink channels;

wherein an indicator change forces a change of transmission/reception mode to said chosen transmission/reception mode for all of said plurality of uplink channels;

an announcement and assignment message having an individual dynamically updated physical layer parameter indicator for a particular downlink channel, said individual dynamically updated physical layer parameter indicator for indicating a decision relating to a chosen transmission/reception mode for performing individual link adaptation for a particular mobile station associated with said particular downlink channel; and

wherein said broadcast message indicates a proper physical layer parameter that is to be used by a receiver to decode said individual dynamically updated physical layer parameter indicator included in the announcement and assignment message.

2. The control frame structure of claim 1, wherein said common dynamically updated physical layer parameter indicator is dynamically changed and included within said broadcast message for a plurality of mobile stations with established uplink channels.

3. The control frame structure of claim 1, wherein said individual dynamically updated physical layer parameter indicator is dynamically changed and included within said announcement and assignment message for an established downlink channel for a particular mobile station.

4. The control frame structure of claim 1, wherein said broadcast message belongs to a broadcast control channel.

5. The control frame structure of claim 1, including a separate control channel for occasional requests of physical layer parameter updates from mobile terminals.

6. A TDMA/TDD link adaptation method, including

determining radio link quality at a central controller;

updating and broadcasting a broadcast message including a common physical layer parameter indicator for a plurality of channels from said central controller, said common physical layer parameter indicator for indicating a decision relating to said determined link quality for performing radio cell adaptation on an associated plurality of uplink channels;

wherein said common physical layer parameter indicator adapts transmission/reception mode for all of said plurality of uplink channels to said determined link quality;

updating and transmitting an announcement and assignment message including an individual physical layer parameter indicator for a particular downlink channel, said individual physical layer parameter indicator for indicating a decision relating to a determined link quality for performing individual link adaptation for a particular mobile station associated with said downlink channel; and

wherein said broadcast message indicates a proper physical layer parameter that is to be used by a receiver to decode said individual physical layer parameter indicator included in the announcement and assignment message.

7. The method of claim 6, wherein said common physical layer parameter indicator is dynamically changed and included within said broadcast message for a plurality of mobile stations with established uplink channels.

8. The method of claim 6, wherein said individual physical layer parameter indicator is dynamically changed and included within said announcement and assignment message for an established downlink channel for a particular mobile station.

9. The method of claim 6, wherein said message belongs to a broadcast control channel.

10. The method of claim 6, including a separate control channel for occasional requests of physical layer parameter updates from mobile terminals.

11. The method of claim 6, wherein said central controller is a base station.

12. A TDMA/TDD radio communications system utilizing a TDMA/TDD media access control frame structure, said system comprising:

a central controller for transmitting a broadcast message having a common dynamically updated physical layer parameter indicator for a plurality of uplink channels, said common dynamically updated physical layer parameter indicator for indicating a decision relating to a chosen transmission/reception mode for performing radio cell adaptation on said associated uplink channels, whereby an indicator change forces a change of transmission/reception mode for all of said plurality of channels to said chosen transmission/reception mode;

wherein said central controller further handles an announcement and assignment message having an individual dynamically updated physical layer parameter indicator for a particular downlink channel, said individual dynamically updated physical layer parameter indicator for indicating a decision relating to a chosen transmission/reception mode for performing individual link adaptation for a particular mobile station associated with said particular downlink channel; and

wherein said broadcast message indicates a proper physical layer parameter that is to be used by a receiver to decode said individual dynamically updated physical layer parameter indicator included in the announcement and assignment message.

13. The system of claim 12, wherein said common dynamically updated physical layer parameter indicator is dynamically changed and included within said broadcast message for a plurality of mobile stations with established uplink channels with said central controller.

14. The system of claim 12, wherein said individual dynamically updated physical layer parameter indicator is dynamically changed and included within said announcement and assignment message for a mobile station with an established downlink channel with said central controller.

15. The system of claim 12, wherein said broadcast message belongs to a broadcast control channel.

16. The system of claim 12, including a separate control channel for occasional requests of physical layer parameter updates from mobile terminals.