Soft discontinuous reception (soft drx)

Abstract

Embodiments of the present disclosure are related to achieving better tradeoffs between battery saving and latency to, e.g., support ultra-low latency applications by introducing soft Discontinuous Reception (DRX). In some embodiments, a method of operation of a node in a wireless communications network comprises initiating transmission, during a DRX awake period, of control information to a wireless device on two or more control channel subsets during two or more time periods within the DRX awake period, respectively. The two or more control channel subsets are different subsets of a plurality of candidate control channels. In some embodiments, the two or more time periods are two or more subframes. The candidate control channels are control channels that the wireless device is configured to monitor. The two or more control channel subsets can be selected to, e.g., reduce latency while not increasing energy consumption as compared to legacy DRX.

1 . A method of operation of a node in a wireless communications network, the method comprising:
 initiating transmission, during a Discontinuous Reception (DRX) awake period of a wireless device, of control information to the wireless device in a time period within the DRX awake period of the wireless device on one or more control channels from one of at least two control channel subsets, wherein the at least two control channel subsets are at least two different subsets of a plurality of candidate control channels that are configured for the wireless device for at least two time periods within the DRX awake period of the wireless device, respectively.   
     
     
         2 . The method of  claim 1 , wherein the at least two time periods are two or more subframes. 
     
     
         3 . The method of  claim 1 , wherein:
 the plurality of candidate control channels comprises a first plurality of candidate Physical Downlink Control Channels (PDCCHs) and a second plurality of candidate enhanced PDCCHs (ePDCCHs); and   the at least two control channel subsets comprise:
 a first control channel subset that comprises at least some of the first plurality of candidate PDCCHs but not any of the second plurality of candidate ePDCCHs; and 
 a second control channel subset that comprises at least some of the second plurality of candidate ePDCCHs but not any of the first plurality of candidate PDCCHs. 
   
     
     
         4 . The method of  claim 1 , wherein the at least two control channel subsets consist of two control channel subsets. 
     
     
         5 . The method of  claim 1 , wherein the at least two control channel subsets comprise a first control channel subset that comprises all of the plurality of candidate control channels and a second control channel subset that comprises less than all of the plurality of candidate control channels. 
     
     
         6 . The method of  claim 1 , wherein initiating the transmission of the control information to the wireless device in the time period within the DRX awake period of the wireless device on said one or more control channels in the one of the at least two control channel subsets comprises:
 determining a first control channel subset for a first time period within the DRX awake period of the wireless device;   initiating the transmission of the control information to the wireless device in one or more candidate control channels in the first control channel subset during the first time period if the wireless device is scheduled in the first time period;   determining a second control channel subset for a second time period within the DRX awake period of the wireless device; and   initiating the transmission of the control information to the wireless device in one or more candidate control channels in the second control channel subset during the second time period if the wireless device is scheduled in the second time period.   
     
     
         7 . The method of  claim 1 , further comprising:
 initiating transmission of one or more soft DRX parameters to the wireless device, the one or more soft DRX parameters comprising information that defines the at least two control channel subsets for the at least two time periods within the DRX awake period, respectively.   
     
     
         8 . A node for operation in a wireless communications network, the node comprising:
 at least one processor; and   memory storing instructions executable by the at least one processor whereby the node is operable to:
 initiate transmission, during a Discontinuous Reception (DRX) awake period of a wireless device, of control information to the wireless device in a time period within the DRX awake period of the wireless device on one or more control channels from one of at least two control channel subsets, wherein the at least two control channel subsets are at least two different subsets of a plurality of candidate control channels that are configured for the wireless device for at least two time periods within the DRX awake period of the wireless device, respectively. 
   
     
     
         9 . The node of  claim 8 , wherein the at least two time periods are two or more subframes. 
     
     
         10 . The node of  claim 8 , wherein:
 the plurality of candidate control channels comprises a first plurality of candidate Physical Downlink Control Channels (PDCCHs) and a second plurality of candidate enhanced PDCCHs (ePDCCHs); and   the at least two control channel subsets comprise:
 a first control channel subset that comprises at least some of the first plurality of candidate PDCCHs but not any of the second plurality of candidate ePDCCHs; and 
 a second control channel subset that comprises at least some of the second plurality of candidate ePDCCHs but not any of the first plurality of candidate PDCCHs. 
   
     
     
         11 . The node of  claim 8 , wherein the at least two control channel subsets consist of two control channel subsets. 
     
     
         12 . The node of  claim 8 , wherein the at least two control channel subsets comprise a first control channel subset that comprises all of the plurality of candidate control channels and a second control channel subset that comprises less than all of the plurality of candidate control channels. 
     
     
         13 . The node of  claim 8 , wherein to initiate the transmission of the control information to the wireless device in the time period within the DRX awake period of the wireless device on said one or more control channels in the one of the at least two control channel subsets, the node is further operable to:
 determine a first control channel subset for a first time period within the DRX awake period of the wireless device;   initiate the transmission of the control information to the wireless device in one or more candidate control channels in the first control channel subset during the first time period if the wireless device is scheduled in the first time period;   determine a second control channel subset for a second time period within the DRX awake period of the wireless device; and   initiate the transmission of the control information to the wireless device in one or more candidate control channels in the second control channel subset during the second time period if the wireless device is scheduled in the second time period.   
     
     
         14 . The node of  claim 8 , further operable to:
 initiate transmission of one or more soft DRX parameters to the wireless device, the one or more soft DRX parameters comprising information that defines the at least two control channel subsets for the at least two time periods within the DRX awake period, respectively.   
     
     
         15 . A non-transitory computer-readable storage medium comprising instructions for operation of a node in a wireless communications network, wherein the instructions, upon execution by a processor of the node, cause the node to:
 initiate transmission, during a Discontinuous Reception (DRX) awake period of a wireless device, of control information to the wireless device in a time period within the DRX awake period of the wireless device on one or more control channels from one of at least two control channel subsets, wherein the at least two control channel subsets are at least two different subsets of a plurality of candidate control channels that are configured for the wireless device for at least two time periods within the DRX awake period of the wireless device, respectively.   
     
     
         16 . The non-transitory computer-readable storage medium of  claim 15 , wherein the instructions further cause the node to limit the transmission of the control information to the wireless device on control channels of the one or more control channels that are being monitored by the wireless device. 
     
     
         17 . The non-transitory computer-readable storage medium of  claim 15 , wherein the at least two time periods are two or more subframes. 
     
     
         18 . The non-transitory computer-readable storage medium of  claim 15 , wherein the at least two control channel subsets consist of two control channel subsets. 
     
     
         19 . The non-transitory computer-readable storage medium of  claim 15 , wherein the at least two control channel subsets comprise a first control channel subset that comprises all of the plurality of candidate control channels and a second control channel subset that comprises less than all of the plurality of candidate control channels. 
     
     
         20 . The non-transitory computer-readable storage medium of  claim 15 , wherein to initiate the transmission of the control information to the wireless device in the time period within the DRX awake period of the wireless device on said one or more control channels in the one of the at least two control channel subsets, the instructions further cause the node to:
 determine a first control channel subset for a first time period within the DRX awake period of the wireless device;   initiate the transmission of the control information to the wireless device in one or more candidate control channels in the first control channel subset during the first time period if the wireless device is scheduled in the first time period;   determine a second control channel subset for a second time period within the DRX awake period of the wireless device; and   initiate the transmission of the control information to the wireless device in one or more candidate control channels in the second control channel subset during the second time period if the wireless device is scheduled in the second time period.