Enhanced node B, user equipment and methods for discontinuous reception in inter-eNB carrier aggregation
View Patent ↗Embodiments of user equipment (UE) and methods for enhanced discontinuous reception (DRX) operations for inter eNB carrier aggregation (CA) in an LTE network are generally described herein. In some embodiments, a UE is configured to be served by multiple serving cells. The first set of the serving cells may be associated with a first eNB and a second set of serving cells may be associated with a second eNB. In these embodiments, DRX operations may be performed independently in multiple serving cells belonging to the different eNBs. Other embodiments for enhanced DRX operations are also described.
1. An apparatus of user equipment (UE) configurable for connectivity with multiple cell groups entities, the apparatus comprising:
memory; and
processing circuitry, configured to:
decode radio-resource control (RRC) signaling from a first cell group associated with a first enhanced node B (eNB), the RRC signaling to configure the UE with a second cell group, the second cell group associated with a secondary eNB, the UE configured to utilize scheduled radio resources of both the first and second cell groups;
decode a first medium-access control (MAC) configuration element received for the first cell group and a second MAC configuration element for the second cell group, the MAC configuration elements to configure the UE for independent discontinuous reception (DRX) operations and independent buffer status reporting operations for each cell group, wherein the first MAC configuration element includes DRX configuration information and buffer status report (BSR) configuration information for the first cell group, and wherein the second MAC configuration element includes DRX configuration information and BSR configuration information for the second cell group;
perform buffer status reporting and DRX operations for the second cell group independently of buffer status reporting and DRX operations for the first cell group, wherein an independent retxBSR-Timer and periodicBSR-Timer are maintained for each of cell group;
configure first uplink data for transmission to the first eNB in accordance with scheduling information received for the first cell group; and
configure second uplink data for transmission to the second eNB in accordance with scheduling information received for the second cell group.
2. The apparatus of claim 1 wherein to perform DRX operations for the first cell group, the processing circuitry is to configure the UE to monitor discontinuously a physical downlink control channel (PDCCH) associated with the first cell group based on the DRX configuration information for the first cell group, wherein to perform DRX operations for the second cell group, the processing circuitry is to configure the UE to monitor discontinuously a PDCCH associated with the second cell group based on the DRX configuration information for the second cell group, and wherein the DRX operations for the first and second cell are performed independently.
3. The apparatus of claim 2 , wherein the DRX configuration information for the first cell group includes an on-duration timer, a DRX inactivity time and a DRX-retransmission timer for the first cell group, and wherein the DRX configuration information for the second cell group includes an on-duration timer, a DRX inactivity time and a DRX-retransmission timer for the second cell group, when DRX is configured for the first cell group, the processing circuitry is to configure the UE to monitor discontinuously the PDCCH associated with the first cell group based on the DRX configuration information for the first cell group, and when DRX is configured for the second cell group, the processing circuitry is to configure the UE to monitor discontinuously the PDCCH associated with the second cell group based on the DRX configuration information for the second cell group.
4. The apparatus of claim 3 wherein the DRX configuration information for the first cell group indicates a first active time and the DRX configuration information for the second cell group indicates a second active time.
5. The apparatus of claim 4 wherein each active time includes time while a scheduling request sent by the UE on a physical uplink control channel (PUCCH) of an associated cell group is pending.
6. The apparatus of claim 4 wherein each active time includes time while an uplink grant for a pending hybrid-automatic repeat request (HARQ) retransmission can occur and data is present in a corresponding HARQ buffer.
7. The apparatus of claim 4 wherein the processing circuitry is further configured to process resource blocks received from the first eNB and the second eNB in accordance with a carrier aggregation technique when the first and second active times are synchronized.
8. The apparatus of claim 1 wherein to perform buffer status reporting for the first cell group, the processing circuitry is to configure the UE to perform a first buffer status reporting procedure, based on the BSR configuration information for the first cell group, to inform the first eNB about data available for transmission in uplink buffers associated with MAC operations for the first eNB; and
wherein to perform buffer status reporting for the second cell group, the processing circuitry is to configure the UE to perform a second buffer status reporting procedure, based on the BSR configuration information for the second cell group, to inform the second eNB about data available for transmission in uplink buffers associated with MAC operations for the second eNB, wherein the first and second buffer status reporting procedures are performed independently.
9. The apparatus of claim 1 further comprising transceiver circuitry to receive the RRC signaling, to transmit BSRs in accordance with the buffer status reporting operations, and to transmit the first and second uplink data.
10. The apparatus of claim 1 wherein the RRC signaling from the first cell group includes information to configure the UE with the second cell group.
11. A non-transitory computer-readable storage medium that stores instructions for execution by processing circuitry of a user equipment (UE) to configure the UE to perform operations to:
decode radio-resource control (RRC) signaling from a first cell group associated with a first enhanced node B (eNB), the RRC signaling to configure the UE with a second cell group, the second cell group associated with a secondary eNB, the UE configured to utilize scheduled radio resources of both the first and second cell groups;
decode a first MAC configuration element received for the first cell group and a second MAC configuration element for the second cell group, the MAC configuration elements to configure the UE for independent discontinuous reception (DRX) operations and independent buffer status reporting operations for each cell group, wherein the first MAC configuration element includes DRX configuration information for the first MAC entity, and wherein the second MAC configuration element includes DRX configuration information for the second cell group;
perform buffer status reporting and DRX operations for the second cell group independently of buffer status reporting and DRX operations for the first cell group, wherein an independent retxBSR-Timer and periodicBSR-Timer are maintained for each of cell group;
configure first uplink data for transmission to the first eNB in accordance with scheduling information received for the first cell group; and
configure second uplink data for transmission to the second eNB in accordance with scheduling information received for the second cell group.
12. The computer-readable storage medium of claim 11 wherein to perform DRX operations for the first cell group, the processing circuitry is to configure the UE to monitor discontinuously a physical downlink control channel (PDCCH) associated with the first cell group based on the DRX configuration information for the first cell group, wherein to perform DRX operations for the second cell group, the processing circuitry is to configure the UE to monitor discontinuously a PDCCH associated with the second cell group based on the DRX configuration information for the second cell group, and wherein the DRX operations for the first and second cell are performed independently.
13. The computer-readable storage medium of claim 12 , wherein the DRX configuration information for the first cell group includes an on-duration timer, a DRX inactivity time and a DRX-retransmission timer for the first cell group, and wherein the DRX configuration information for the second cell group includes an on-duration timer, a DRX inactivity time and a DRX-retransmission timer for the second cell group, when DRX is configured for the first cell group, the processing circuitry is to configure the UE to monitor discontinuously the PDCCH associated with the first cell group based on the DRX configuration information for the first cell group, and when DRX is configured for the second cell group, the processing circuitry is to configure the UE to monitor discontinuously the PDCCH associated with the second cell group based on the DRX configuration information for the second cell group.
14. The computer-readable storage medium of claim 13 wherein the DRX configuration information for the first cell group indicates a first active time and the DRX configuration information for the second cell group indicates a second active time.
15. An apparatus of user equipment (UE) configurable for connectivity with two cell groups, the apparatus comprising:
memory; and
processing circuitry, configured to:
decode a first medium-access control (MAC) configuration element received for the first cell group and a second MAC configuration element for the second cell group, the MAC configuration elements to configure the UE for independent buffer status reporting operations for each cell group, wherein the first MAC configuration element includes buffer status report (BSR) configuration information for the first cell group, and wherein the second MAC configuration element includes BSR configuration information for the second cell group;
maintain an independent retxBSR-Timer and periodicBSR-Timer for each of cell group;
perform buffer status reporting operations for the second cell group independently of buffer status reporting operations for the first cell group;
configure BSRs for transmission to the first eNB in accordance with scheduling information received for the first cell group; and
configure BSRs for transmission to the second eNB in accordance with scheduling information received for the second cell group.
16. The apparatus of claim 15 wherein the processing circuitry is further configured to decode radio-resource control (RRC) signaling from the first cell group associated with a first enhanced node B (eNB), the RRC signaling to configure the UE with the second cell group, the second cell group associated with a secondary eNB, the UE configured to utilize scheduled radio resources of both the first and second cell groups.
17. The apparatus of claim 16 wherein to perform buffer status reporting for the first cell group, the processing circuitry is to configure the UE to perform a first buffer status reporting procedure, based on the BSR configuration information for the first cell group, to inform the first eNB about data available for transmission in uplink buffers associated with MAC operations for the first eNB; and
wherein to perform buffer status reporting for the second cell group, the processing circuitry is to configure the UE to perform a second buffer status reporting procedure, based on the BSR configuration information for the second cell group, to inform the second eNB about data available for transmission in uplink buffers associated with MAC operations for the second eNB, wherein the first and second buffer status reporting procedures are performed independently.