US-20260129715-A1 - ENHANCED CONNECTED MODE DRX PROCEDURES FOR NR

US20260129715A1US 20260129715 A1US20260129715 A1US 20260129715A1US-20260129715-A1

Abstract

Embodiments described herein include DRX operations that address impacts of beamforming to current DRX operations. It is recognized herein that the new NR-PDCCH may affect the downlink control channel monitoring in DRX operations. DRX embodiments described herein also address the impact of new NR-PDCCH to DRX operations. It is further recognized herein that, in NR, multiple DRX configurations may be supported, and L1/2 signaling (such as MAC CE based) can be used for dynamic DRX configuration switching. Embodiments described herein include signaling and other mechanisms that support multiple DRX configurations, and switching between multiple configurations. Embodiments described herein also include DRX operations that address the impact of HARQ design in NR to DRX operations. Embodiments described herein further include DRX operations that address the impact of multiple SR configurations in NR to DRX operation.

Inventors

Guodong Zhang
Pascal M. Adjakple
Lakshmi R. Iyer
Stephen E. Terry
Qing Li

Assignees

INTERDIGITAL PATENT HOLDINGS, INC.

Dates

Publication Date: 20260507
Application Date: 20251219

Claims (1)

1 . An apparatus comprising a processor, a memory, and communication circuitry, the apparatus being connected to a network via its communication circuitry, the apparatus further comprising computer-executable instructions stored in the memory of the apparatus which, when executed by the processor of the apparatus, cause the apparatus to perform operations comprising: receiving a configuration signal; and based on the configuration signal, determining a processor interrupt time unit to be used for timing of a medium access control (MAC) procedure, wherein the processor interrupt time unit is based on at least one of: a capability of the apparatus, a minimum slot duration associated with the apparatus, or a minimum slot duration associated with a numerology.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Application No. 62/543,755, filed on Aug. 10, 2017, U.S. Provisional Application No. 62/564,461, filed on Sep. 28, 2017, and U.S. Provisional Application No. 62/615,773, filed on Jan. 10, 2018, the contents of which are hereby incorporated by reference in their entireties. BACKGROUND In LTE/LTE-A, a user equipment (UE) in a connected mode (RRC_CONNECTED state) monitors the Physical Downlink Control Channel (PDCCH) to get the downlink transmission grant for the UE to receive downlink data on the Physical Downlink Shared Channel (PDSCH) A connected state discontinuous reception (DRX) procedure is introduced in LTE/LTE-A standards to achieve UE power savings. A DRX cycle consists of an “On Duration” and a “DRX period.” During the “On Duration,” a UTE monitors the PDCCH for grant. Whenever a grant is received, the UE will start an “Inactive Timer.” The LE keeps monitoring the PDCCH until the Inactive Timer expires or is stopped by a media access control (MAC) command. Then the UE is in the DRX period, during which the UE can go into a sleep mode to save power A high level example of DRX operations are depicted in FIG. 1. Referring to FIG. 2, the example DRX operation is depicted after an uplink (UL) data transmission with asynchronous hybrid automatic repeat request (HARQ). In accordance with LTE Release 13, after a UL data transmission using a UL HARQ process, a UL HARQ RTT timer is started for the UL HARQ process. In some cases, the UE need not monitor the DCI for the UL HARQ process, which means that the UE can sleep while the UL HARQ RTT timer runs if there is no other activity for the UE. When the UL HARQ RTT timer expires, the LIE may start a drx-ULRetransmissionTimer for the UL HARQ process. When this timer is running, the UE monitors the PDCCH for retransmissions. In some cases, if the UE detects the PDCCH when the drx-ULRetransmissionTimer is running, the timer is stopped. Otherwise, if the drx-ULRetransmissionTimer expires and no other DRX timers are running, the UE may stop monitoring the PDCCH and might not be reachable until the next valid on Duration period. The operation in the downlink may be substantially the same as the uplink. In LTE, the fixed timing relations for the HARQ transmissions can impose a delay regardless whether downlink or uplink data transmissions are considered. To allow for energy saving during retransmissions for the UE when entering DRX (e.g., when the drx-InactivityTimer has expired), HARQ RTT timers enable the UE to know when to not monitor the downlink for retransmissions, and when to start monitoring the DL (e.g., see FIG. 3). When asynchronous HARQ is used in the downlink, there may be a fixed delay for transmitting the HARQ acknowledgement. Further, in some cases, there is a need for the DL HARQ RTT timer and the drx-RetransmissionTimer to control how long the UE continues to monitor the DL for a retransmission, for example, to allow for energy savings in the UE. A DRX cycle in which no grant is received is called a connected DRX (CDRX) state. A DRX cycle in which a grant is received is considered an Active state. In CDRX cycles, for example, the UE may: 1) wake up from deep sleep; 2) spend time and energy on ramp-up; 3) monitor the PDCCH for ON duration; and 4) ramp down and go back to sleep. SUMMARY Embodiments described herein include DRX operations that address impacts of beamforming to current DRX operations. It is recognized herein that the new NR-PDCCH may affect the downlink control channel monitoring in DRX operations. DRX embodiments described herein also address the impact of new NR-PDCCH to DRX operations. It is further recognized herein that, in NR, multiple DRX configurations may be supported, and L1/2 signaling (such as MAC CE based) can be used for dynamic DRX configuration switching. Embodiments described herein include signaling and other mechanisms that support multiple DRX configurations, and switching between multiple configurations. Embodiments described herein also include DRX operations that address the impact of HARQ design in NR to DRX operations. Embodiments described herein further include DRX operations that address the impact of multiple SR configurations in NR to DRX operation. In an example, an apparatus (e.g., UE), receives a configuration signal, and, based on the configuration signal, determines a processor interrupt time unit to be used for timing of a medium access control (MAC) procedure. The processor interrupt time unit may be based on at least one of: a capability of the apparatus, a minimum slot duration associated with the apparatus, or a minimum slot duration associated with a numerology. The capability of the apparatus may include a battery level associated with the apparatus, a category of the apparatus, or a power setting associated with the apparatus. The numerology may be an active uplink numerology, an active downlink numero