Power and timing control methods and apparatus

Abstract

The use of multiple states of mobile communication device operation to allow a single base station to support a relatively large number of mobile nodes is described. The various states require different amounts of communications resources, e.g., bandwidth. Four supported states of operation are an on-state, a hold-state, a sleep-state, and an access-state. Each mobile node in the on-state is allocated communication resources to perform transmission power control signaling, transmission timing control signaling and to transmit data as part of a data uplink communications operation. Each mobile node in the hold-state is allocated communication resources to perform transmission timing control signaling and is provided a dedicated uplink for requesting a state transition and a shared resource for transmitting acknowledgements. In the sleep state a mobile node is allocated minimal resources and does not conduct power control signaling or timing control signaling. Data may be received in the on and hold states.

1 . A communications method, the method comprising: 
 operating a first wireless terminal, at different times, in each one of three different operational states, the three different operational states including a first state, a second state and a third state,    wherein operating the first wireless terminal in the first state includes using a first amount of a control communications resource to communicate control information between said first wireless terminal and a base station;    wherein operating the first wireless terminal in the second state includes using a second amount of the control communications resource to communicate control information between said first wireless terminal and the base station, the second amount of control communications resource being less than the first amount; and    wherein operating the first wireless terminal in the third state includes using less of the control communications resource than is used by the first wireless terminal in either of the first or second states.    
     
     
         2 . The communications method of  claim 1 , wherein operating the first wireless terminal in the first state to use a first amount of a control communications resource includes: 
 operating the first wireless terminal to perform power control signaling operations and timing control signaling operations.    
     
     
         3 . The method of  claim 2 , further comprising: 
 operating the first wireless terminal to transition from the first state to the second state, said transitioning including reducing the rate of power control signaling operations performed by said first wireless terminal.    
     
     
         4 . The method of  claim 3 , further comprising: 
 operating the first wireless terminal to transition from said second state to the third state, the step of transitioning from said second state to said third state including ceasing to perform transmission timing control updates.    
     
     
         5 . The method of  claim 3 , wherein reducing the rate of power control signaling includes ceasing to monitor for power control signals from the base station.  
     
     
         6 . The method of  claim 3 , wherein reducing the rate of power control signaling operations includes performing transmission power control update operations at a greater interval than transmission power control update operations were performed in said first state.  
     
     
         7 . The method of  claim 6 , wherein transitioning from the second state to the third state includes operating the first wireless terminal to cease performing transmission power control update operations.  
     
     
         8 . The method of  claim 2 , further comprising the step of: 
 operating the first wireless terminal to transition from said third state to one of said first and said second states, the step of transitioning to one of said first and second states including resuming transmission timing control update operations.    
     
     
         9 . The method of  claim 8 , wherein operating the first wireless terminal to transition from said third state to one of said first state and said second state includes operating the first wireless terminal to resume transmission power control signaling operations.  
     
     
         10 . The method of  claim 9 , wherein operating the first wireless terminal to resume transmission timing control signaling includes: 
 transmitting a request to the base station for the allocation of communications resources required to perform transmission timing control signaling.    
     
     
         11 . The method of  claim 10 , wherein transmitting a request for communications resources required to perform transmission timing control signaling includes: 
 transmitting said request using a shared segment of a communications channel.    
     
     
         12 . The method of  claim 11 , further comprising: 
 operating the first wireless terminal to transition from said second state to said first state, the step of transitioning from said second state to said first state including transmitting a request for a dedicated communications resource that can be used to transmit data to be communicated to said base station.    
     
     
         13 . The method of  claim 9 , wherein operating the first wireless terminal to transmit a request for a dedicated communications resource that can be used to transmit data includes transmitting the resource request to a base station using a dedicated resource request uplink assigned to the first wireless terminal.  
     
     
         14 . The method of  claim 1 , wherein said control communications resource is control signaling bandwidth used for communicating control signals between said base station and a plurality of wireless terminals served by said base station.  
     
     
         15 . The method of  claim 14 , wherein said first state is an on state, said second state is a hold state, and said third state is a sleep state, the method further comprising: 
 operating the first wireless terminal to transmit and receive data as part of a communications session with another terminal during at least a portion of said on state.    
     
     
         16 . The method of  claim 15 , further comprising: 
 operating the first wireless terminal to receive data from another terminal during at least a portion of said hold state without transmitting data at any time while operating in said hold state.    
     
     
         17 . The method of  claim 16 , wherein operating said first wireless terminal in said sleep state includes controlling said wireless terminal so that data corresponding to a communications session is neither transmitted from said first wireless terminal or received by said first wireless terminal during any portion of said sleep state.  
     
     
         18 . The method of  claim 1 , wherein said first state is an on state, said second state is a hold state, and said third state is a sleep state, the method further comprising: 
 operating a second wireless terminal, at different times, in each one of said on state, said hold state and said sleep state;    wherein operating the second wireless terminal in the on state includes using a fourth amount of control communications bandwidth to communicate control information between said second wireless tenrminal and said base station; and    wherein operating the second wireless terminal in the hold state includes using a fifth amount of the control communications bandwidth to communicate control information between said second wireless terminal and the base station, the fifth amount of control communications bandwidth being less than the first amount.    
     
     
         19 . The method of  claim 18 , further comprising 
 operating the second wireless terminal to transmit and receive data as part of a communications session with another terminal during at least a portion of time during which said second terminal is operated in said on state.    
     
     
         20 . The method of  claim 19 , further comprising: 
 operating the second wireless terminal to receive data from another terminal during at least a portion of the time said second wireless terminal is operated in said hold state without transmitting data at any time while operating said second wireless terminal in said hold state.    
     
     
         21 . The method of  claim 20 , wherein operating said second wireless terminal in said sleep state includes controlling said second wireless terminal so that data corresponding to a communications session is neither transmitted from said second wireless terminal or received by said second wireless terminal during any portion of time said wireless terminal is operated in said sleep state.  
     
     
         22 . The method of  claim 19 , 
 wherein said data to be transmitted as part of a communications session includes IP packets at least some of which include speech data; and    wherein said second wireless terminal transmits said IP packets to said base station using orthogonal frequency division multiplexed signals.    
     
     
         23 . A mobile communications device including: 
 control means used to control the mobile communications device to:    i) operate in an on state in which the mobile communications device uses a first amount of control signaling resources for the communication of control information between said mobile communications device and a base station;    ii) transition the mobile communications device from the on state to a hold state in which the first mobile communications device uses less control signaling resources for the communication of control information between said mobile device and a base station than is used by the mobile communications device in the on state; and    iii) transition the mobile communications device from said hold-state to a sleep state in which the mobile communications device uses less control signaling resources than the mobile communications device uses in said hold state.    
     
     
         24 . The mobile communications device of  claim 23 , wherein said control means controls the mobile communications device to perform transmission timing control signaling operations, transmission power control signaling operations, and transmit data, during said on state.  
     
     
         25 . The mobile communications device of  claim 24 , wherein said control means controls the mobile communications device, as part of transitioning from said on-state to said hold state, to reduce the rate of power control signaling operations performed by said first mobile communications device.  
     
     
         26 . The mobile communications device of  claim 25 , wherein said control means controls the mobile communications device, as part of transitioning from said hold-state to said sleep-state, to cease performing transmission timing control update operations.  
     
     
         27 . The mobile communications device of  claim 25 , further comprising: 
 means for controlling the mobile communications device to transition from said sleep-state to one of said on-state and said hold-state, wherein transitioning to one of said on-state and said hold-state includes resuming transmission timing control update operations.    
     
     
         28 . The mobile communications device of  claim 27 , further comprising: 
 means for controlling the mobile communications device to transition from said hold-state to said on-state, wherein transitioning from said hold-state to said-on state includes transmitting a request for a dedicated communications resource that can be used to transmit data to be communicated to said base station.    
     
     
         29 . A communications system comprising: 
 a base station, said base station controlling the allocation of control signaling resources and data transmission resources to a plurality of mobile nodes serviced by said base station, said base station controlling a first subset of said plurality of mobile nodes to operate in an on state wherein nodes in said first subset are allocated data communication resources to transmit data and control signaling resources to perform a first level of control signaling, said base station further controlling a second subset of said plurality of mobile nodes to operate in an hold state wherein nodes in said second subset are allocated control signaling resources to perform a second level of control signaling which is less than said first level of control signaling; and    said base station further controlling a third subset of said plurality of mobile nodes to operate in a sleep state wherein nodes in said third subset are allocated less control signaling resources than mobile nodes in either said first subset or said second subset.    
     
     
         30 . The communications system of  claim 29 , wherein the system includes said plurality of mobile nodes, the first subset of mobile nodes includes means for performing transmission timing control signaling operations and transmission power control signaling operations while in said on state.  
     
     
         31 . The communications system of  claim 30 , wherein the second subset of mobile nodes includes means for performing transmission timing control signaling operations and reduced rate transmission power control signaling operations while in said hold state.  
     
     
         32 . The communications system of  claim 30 , wherein said second subset of mobile nodes includes means for reducing the rate of transmission power control signaling operations as part of transitioning from said on state to said hold state.  
     
     
         33 . The communication system of  claim 32 , wherein said second set of mobile nodes includes means for halting transmission power control update operations when transitioning into said hold state from said on state.  
     
     
         34 . The communication system of  claim 32 , wherein said third subset of mobile nodes includes means for terminating the transmission of timing control signals when transitioning into said sleep state from said hold state.  
     
     
         35 . The system of  claim 29 , further comprising said plurality of mobile nodes, the third subset of mobile nodes including more communications devices than said second subset of mobile nodes.  
     
     
         36 . The system of  claim 35 , wherein the second subset of mobile nodes includes more nodes than said first subset of mobile nodes.  
     
     
         37 . The system of  claim 36 , wherein said third subset of mobile nodes do not perform transmission power control signaling operations.  
     
     
         38 . The system of  claim 37 , wherein said second subset of mobile nodes do not perform transmission power control signaling operations.  
     
     
         39 . The system of  claim 37 , wherein said second subset of mobile nodes perform power control signaling operations at a rate which is lower than the rate at which mobile nodes in said first subset perform transmission power control signaling operations.