Methods for carrier agggregation

Abstract

Methods to manage multiple component carriers (CCs) efficiently in a mobile network with carrier aggregation (CA) enabled are proposed. For CC activation/deactivation, a single LCID value is used to represent both activation and deactivation command. A single command with multiple instructions is provided to activate and/or deactivate multiple CCs. In addition, unnecessary re-activation or re-inactivation of a CC is prevented, and explicit feedback for activation/deactivation is considered. For scheduling mechanism, a novel buffer status reporting (BSR) procedure is provided, where only one BSR is calculated after preparing all the transport blocks (TB) within one transmission time interval (TTI). Novel power headroom reporting (PHR) format and trigger are also provided. For DL-UL linking, various linking types are created based on whether there is carrier indicator field (CIF) in DL grant or UL grant. The various linking types are used in different applications to improve scheduling flexibility and load balancing.

1 . A method comprising:
 receiving a activation or deactivation command for one or more component carriers (CCs) by a user equipment (UE) in a wireless communication network;   deriving a plurality of instructions corresponds to the one or more CCs based on the command, wherein the UE activates a CC if a current state of the CC is deactivated and a corresponding instruction is for activation, wherein the UE deactivates the CC if the current state of the CC is activated and a corresponding instruction is for deactivation, and wherein the UE does not change the current state of the CC otherwise.   
     
     
         2 . The method of  claim 1 , wherein the command is contained in a media access control (MAC) control element (CE), and wherein each bit is associated with an activation or deactivation instruction for a corresponding CC. 
     
     
         3 . The method of  claim 1 , further comprising:
 starting an deactivation timer for a secondary CC (SCC) based on a set of predefined events; and   deactivating the SCC when the deactivation timer expires.   
     
     
         4 . The method of  claim 3 , wherein the set of predefined events comprises at least one of a secondary CC is activated, a downlink assignment is received, an uplink grant is received, a configured transmission takes place, and an activation command is received. 
     
     
         5 . The method of  claim 1 , further comprising:
 transmitting feedback information in respond to an activation or deactivation status.   
     
     
         6 . The method of  claim 1 , wherein the UE activates a secondary CC (SCC), the activation involves:
 activating the SCC before a predefined time;   staring a deactivation timer associated with the SCC; and   triggering a power headroom reporting (PHR) procedure associated with the SCC.   
     
     
         7 . The method of  claim 1 , wherein the UE deactivates a secondary CC (SCC), the deactivation involves:
 deactivating the SCC before a predefined time;   stopping a deactivation timer associated with the SCC; and   flushing all Hybrid ARQ (HARQ) buffers associated with the SCC.   
     
     
         8 . A method of buffer station reporting (BSR) and power headroom reporting (PHR), the method comprising:
 reporting buffer status information by a user equipment in a wireless communication network; and   reporting power headroom information for a plurality of component carriers (CCs) by the UE, wherein the reporting is triggered by an uplink CC, wherein the power headroom information is reported via a media access control (MAC) control element (CE) that includes a carrier index of the uplink CC.   
     
     
         9 . The method of  claim 8 , wherein only one BSR is calculated after preparing all the transport blocks (TB) within one transmission time interval (TTI) with multiple uplink grants. 
     
     
         10 . The method of  claim 8 , wherein multiple padding BSR is included on different transport blocks (TBs) within one transmission time interval (TTI). 
     
     
         11 . The method of  claim 8 , wherein multiple uplink CCs trigger PHR, and wherein power headroom information for the multiple uplink CCs are reported via a single transmission block (TB). 
     
     
         12 . The method of  claim 8 , wherein independent physical uplink control channel (PUCCH) PHR and physical uplink shared channel (PUSCH) PHR are transmitted simultaneously. 
     
     
         13 . The method of  claim 8 , wherein the reporting is triggered when an uplink secondary CC (SCC) is activated. 
     
     
         14 . A method, comprising:
 receiving a downlink (DL) or an uplink (UL) grant from a serving base station by a user equipment (UE) in a multi-carrier wireless communication network;   establishing a linking between a downlink component carrier (CC) and an uplink CC based on the grant, wherein the grant optionally contains no carrier index information.   
     
     
         15 . The method of  claim 14 , wherein the grant is a UL grant containing carrier index information via a specific DL CC, wherein the linking is a dynamic linking that links the specific DL CC to UL CCs defined in the UL grant, and wherein the dynamic linking lasts the lifecycle of the UL grant. 
     
     
         16 . The method of  claim 14 , wherein the grant is a DL grant containing carrier index information, wherein the UE replies an acknowledgment via a PUCCH semi-statically configured on a UL primary CC (PCC), and wherein the linking is a DL semi-dynamic linking that links the UL PCC to DL CCs defined in the DL grant. 
     
     
         17 . The method of  claim 14 , wherein the grant is a DL grant containing no carrier index information via a specific DL CC, wherein the UE replies an acknowledgment via a PUCCH semi-statically configured on a UL primary CC (PCC), and wherein the linking is a DL semi-static linking that links the UL PCC to the specific DL CC. 
     
     
         18 . The method of  claim 14 , wherein the grant is a UL grant containing no carrier index information via a specific DL CC, wherein the linking is a UL semi-static linking that links a semi-static UL CC to the specific DL CC, and wherein the UL semi-static linking is created at the time of the UL CC addition and lasts till the time of the UL CC removal. 
     
     
         19 . The method of  claim 14 , wherein the grant is a UL grant containing no carrier index information via a specific DL CC, wherein the linking is a UL semi-static linking that links multiple UL CCs to the specific DL CC. 
     
     
         20 . The method of  claim 14 , wherein the grant is a UL grant for random access (RA) containing no carrier index information via a specific DL CC, and wherein the linking is a UL semi-static linking that links a semi-static UL CC to the specific DL CC. 
     
     
         21 . The method of  claim 14 , wherein the grant is for CC addition or CC removal, and wherein the linking is static, dynamic, DL semi-static, or UL semi-static. 
     
     
         22 . A method comprising:
 preparing a first amount of system information in a multi-carrier wireless communication network; and   transmitting the first amount of system information via dedicate signaling, where in the first amount of system information is used to configure one or multiple SCells, and wherein the first amount of system information via dedicate signaling is different from a second amount of system information via broadcast signaling.