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US-20260128836-A1 - METHODS AND APPARATUS FOR SIGNALING AND STATE TRANSITION FOR PDCCH SKIPPING AND SSSG SWITCHING

US20260128836A1US 20260128836 A1US20260128836 A1US 20260128836A1US-20260128836-A1

Abstract

Systems and methods provide for physical downlink control channel (PDCCH) monitoring adaptation. A user equipment (UE) may monitor a default search space set group (SSSG) for downlink control information (DCI) from a base station in the PDCCH. In response to a first DCI trigger, the UE switches from monitoring the default SSSG to monitoring a first non-default SSSG associated with a first timer. In response to a second DCI trigger, the UE switches from monitoring the first non-default SSSG to monitoring a second non-default SSSG associated with a second timer. The first non-default SSSG may be a non-empty SSSG including a search space set with at least one associated search space. The second non-default SSSG may be an empty SSSG with no associated search space to emulate PDCCH skipping.

Inventors

  • Huaning Niu
  • Dawei Zhang
  • Haitong Sun
  • Hong He
  • Oghenekome Oteri
  • Sigen Ye
  • Wei Zeng
  • Weidong Yang
  • Yushu Zhang

Assignees

  • APPLE INC.

Dates

Publication Date
20260507
Application Date
20251218

Claims (20)

  1. 1 . A method for a user equipment (UE) for physical downlink control channel (PDCCH) monitoring adaptation, the method comprising: monitoring a default search space set group (SSSG) for downlink control information (DCI) from a base station in the PDCCH; in response to a DCI trigger, switching between monitoring the default SSSG, monitoring a first non-default SSSG, and monitoring a second non-default SSSG, wherein the DCI trigger comprises two bits, and wherein a first value the two bits indicates a first SSSG configuration corresponding to the default SSSG, a second value of the two bits indicates a second SSSG configuration corresponding to the first non-default SSSG and to set a timer, and a third value of the two bits indicates a third SSSG configuration corresponding to the second non-default SSSG and to set the timer, and wherein: when the two bits indicate a new SSSG configuration that is the same as a current SSSG configuration, the timer continues to count down; and when the two bits indicate the new SSSG configuration is different than the current SSSG configuration, the timer resets; and in response to the timer expiring, switching to monitoring the default SSSG.
  2. 2 . The method of claim 1 , wherein the first non-default SSSG is a non-empty SSSG comprising a search space set with at least one associated search space, and wherein the second non-default SSSG is an empty SSSG with no associated search space to emulate PDCCH skipping.
  3. 3 . The method of claim 2 , further comprising, while monitoring the second non-default SSSG, switching from monitoring the second non-default SSSG to monitoring either the default SSSG or the first non-default SSSG in response to the DCI trigger.
  4. 4 . The method of claim 2 , further comprising, while monitoring the second non-default SSSG, returning to a previous monitoring configuration in response to the timer expiring.
  5. 5 . The method of claim 4 , further comprising switching from monitoring the default SSSG to monitoring the second non-default SSSG, wherein returning to the previous monitoring configuration comprises switching back from monitoring the second non-default SSSG to monitoring the default SSSG in response to the timer expiring.
  6. 6 . The method of claim 4 , further comprising switching from monitoring the first non-default SSSG to monitoring the second non-default SSSG, wherein returning to the previous monitoring configuration comprises switching back from monitoring the second non-default SSSG to monitoring the first non-default SSSG in response to the timer expiring.
  7. 7 . The method of claim 6 , further comprising continuing to run the timer after switching from monitoring the first non-default SSSG to monitoring the second non-default SSSG.
  8. 8 . The method of claim 7 , further comprising, after the timer expires, falling back to monitoring the default SSSG.
  9. 9 . The method of claim 6 , further comprising: pausing the timer after switching from monitoring the first non-default SSSG to monitoring the second non-default SSSG; and resuming the timer after switching back from monitoring the second non-default SSSG to monitoring the first non-default SSSG.
  10. 10 . The method of claim 2 , further comprising, while monitoring the second non-default SSSG, switching from the second non-default SSSG to the default SSSG in response to the timer expiring regardless of a previous monitoring configuration.
  11. 11 . The method of claim 10 , further comprising: switching from monitoring the first non-default SSSG to monitoring the second non-default SSSG; resetting the timer; and in response to the timer expiring, switching from the second non-default SSSG to the default SSSG.
  12. 12 . The method of claim 2 , wherein the DCI trigger comprises an SSSG bit and a PDCCH skipping bit, the method further comprising switching from monitoring the default SSSG to monitoring the first non-default SSSG in response to the SSSG bit being set.
  13. 13 . The method of claim 12 , wherein the PDCCH skipping bit of the DCI trigger is also set, the method further comprising performing PDCCH skipping using a first skipping duration associated with the default SSSG in response to the PDCCH skipping bit being set before switching from monitoring the default SSSG to monitoring the first non-default SSSG in response to the SSSG bit being set.
  14. 14 . The method of claim 13 , while monitoring the second non-default SSSG, the method further comprises: determining the SSSG bit and the PDCCH skipping bit in the DCI trigger; when the PDCCH skipping bit in the DCI trigger is set and the SSSG bit in the DCI trigger is not set, performing PDCCH skipping using a second skipping duration associated with the first non-default SSSG; when the PDCCH skipping bit in the DCI trigger is not set and the SSSG bit in the DCI trigger is set, or in response to the timer expiring, switching from monitoring the first non-default SSSG to monitoring the default SSSG; and when both the PDCCH skipping bit in the DCI trigger is set and the SSSG bit in the DCI trigger is set, performing PDCCH skipping using the second skipping duration before switching from monitoring the first non-default SSSG to monitoring the default SSSG.
  15. 15 . The method of claim 14 , while monitoring the second non-default SSSG, when the PDCCH skipping bit in the DCI trigger is set, the method further comprises: pausing the timer while performing PDCCH skipping using the second skipping duration; and resuming the timer after performing PDCCH skipping using the second skipping duration.
  16. 16 . The method of claim 14 , while monitoring the second non-default SSSG, when the PDCCH skipping bit in the DCI trigger is set, the method further comprises: continuing counting using the timer while performing PDCCH skipping using the second skipping duration; and after performing PDCCH skipping using the second skipping duration, in response to the timer expiring, switching back from monitoring the first non-default SSSG to monitoring the default SSSG.
  17. 17 . The method of claim 1 , further comprising determining an SSSG pattern of the default SSSG based on a DCI format associated with a radio resource control (RRC) configuration of the default SSSG, wherein when a DCI format 2-6 is enabled the SSSG pattern of the default SSSG comprises a dense pattern, and wherein when the DCI format 2-6 is not enabled the SSSG pattern of the default SSSG comprises a sparse pattern.
  18. 18 . The method of claim 1 , wherein a fourth value of the two bits indicates that no SSSG switching is to occur between the first SSSG configuration, the second SSSG configuration, and the third SSSG configuration.
  19. 19 . A baseband processor of a user equipment (UE) configured for physical downlink control channel (PDCCH) monitoring adaptation, the baseband processor comprising circuitry configured to: monitor a default search space set group (SSSG) for downlink control information (DCI) from a base station in the PDCCH; in response to a DCI trigger, switch between monitoring the default SSSG, monitoring a first non-default SSSG, and monitoring a second non-default SSSG, wherein the DCI trigger comprises two bits, and wherein a first value the two bits indicates a first SSSG configuration corresponding to the default SSSG, a second value of the two bits indicates a second SSSG configuration corresponding to the first non-default SSSG and to set a timer, and a third value of the two bits indicates a third SSSG configuration corresponding to the second non-default SSSG and to set the timer, and wherein: when the two bits indicate a new SSSG configuration that is the same as a current SSSG configuration, the timer continues to count down; and when the two bits indicate the new SSSG configuration is different than the current SSSG configuration, the timer resets; and in response to the timer expiring, switch to monitoring the default SSSG.
  20. 20 . A user equipment (UE) configured for physical downlink control channel (PDCCH) monitoring adaptation, wherein the UE is further configured to: monitor a default search space set group (SSSG) for downlink control information (DCI) from a base station in the PDCCH; in response to a DCI trigger, switch between monitoring the default SSSG, monitoring a first non-default SSSG, and monitoring a second non-default SSSG, wherein the DCI trigger comprises two bits, and wherein a first value the two bits indicates a first SSSG configuration corresponding to the default SSSG, a second value of the two bits indicates a second SSSG configuration corresponding to the first non-default SSSG and to set a timer, and a third value of the two bits indicates a third SSSG configuration corresponding to the second non-default SSSG and to set the timer, and wherein: when the two bits indicate a new SSSG configuration that is the same as a current SSSG configuration, the timer continues to count down; and when the two bits indicate the new SSSG configuration is different than the current SSSG configuration, the timer resets; and in response to the timer expiring, switch to monitoring the default SSSG.

Description

TECHNICAL FIELD This application relates generally to wireless communication systems, including adaptive physical downlink control channel (PDCCH) monitoring. BACKGROUND Wireless mobile communication technology uses various standards and protocols to transmit data between a base station and a wireless communication device. Wireless communication system standards and protocols can include, for example, 3rd Generation Partnership Project (3GPP) long term evolution (LTE) (e.g., 4G), 3GPP new radio (NR) (e.g., 5G), and IEEE 802.11 standard for wireless local area networks (WLAN) (commonly known to industry groups as Wi-Fi®). As contemplated by the 3GPP, different wireless communication systems standards and protocols can use various radio access networks (RANs) for communicating between a base station of the RAN (which may also sometimes be referred to generally as a RAN node, a network node, or simply a node) and a wireless communication device known as a user equipment (UE). 3GPP RANs can include, for example, global system for mobile communications (GSM), enhanced data rates for GSM evolution (EDGE) RAN (GERAN), Universal Terrestrial Radio Access Network (UTRAN), Evolved Universal Terrestrial Radio Access Network (E-UTRAN), and/or Next-Generation Radio Access Network (NG-RAN). Each RAN may use one or more radio access technologies (RATs) to perform communication between the base station and the UE. For example, the GERAN implements GSM and/or EDGE RAT, the UTRAN implements universal mobile telecommunication system (UMTS) RAT or other 3GPP RAT, the E-UTRAN implements LTE RAT (sometimes simply referred to as LTE), and NG-RAN implements NR RAT (sometimes referred to herein as 5G RAT, 5G NR RAT, or simply NR). In certain deployments, the E-UTRAN may also implement NR RAT. In certain deployments, NG-RAN may also implement LTE RAT. A base station used by a RAN may correspond to that RAN. One example of an E-UTRAN base station is an Evolved Universal Terrestrial Radio Access Network (E-UTRAN) Node B (also commonly denoted as evolved Node B, enhanced Node B, eNodeB, or eNB). One example of an NG-RAN base station is a next generation Node B (also sometimes referred to as a g Node B or gNB). A RAN provides its communication services with external entities through its connection to a core network (CN). For example, E-UTRAN may utilize an Evolved Packet Core (EPC), while NG-RAN may utilize a 5G Core Network (5GC). BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS To easily identify the discussion of any particular element or act, the most significant digit or digits in a reference number refer to the figure number in which that element is first introduced. FIG. 1A illustrates an example of switching PDCCH monitoring periodicity in accordance with one embodiment. FIG. 1B illustrates an example of skipping PDCCH search space monitoring in accordance with one embodiment. FIG. 1C illustrates an example of switching PDCCH monitoring and skipping PDCCH monitoring in accordance with one embodiment. FIG. 2 illustrates an SSSG switching state diagram for non-default SSSG to non-default SSSG switching using multiple timers in accordance with one embodiment. FIG. 3 illustrates a skipping with SSSG switching state diagram in accordance with one embodiment. FIG. 4 illustrates a flowchart of a method for a UE to perform PDCCH monitoring adaptation in accordance with one embodiment. FIG. 5 illustrates an example architecture of a wireless communication system, according to embodiments disclosed herein. FIG. 6 illustrates a system for performing signaling between a wireless device and a network device, according to embodiments disclosed herein. DETAILED DESCRIPTION Various embodiments are described with regard to a UE. However, reference to a UE is merely provided for illustrative purposes. The example embodiments may be utilized with any electronic component or device that may establish a connection to a network and is configured with the hardware, software, and/or firmware to exchange information and data with the network. Therefore, the UE as described herein is used to represent any appropriate electronic component or device. Effort is made in the telecommunication industry to improve the power consumption of NR mobile devices. For example, NR systems support a connected mode, an idle mode, and an inactive mode. In a connected mode, a UE can receive and/or send traffic from/to a network. If no traffic exists, the UE can move to the idle mode and then, depending on the inactivity, to the inactive mode. In the idle and inactive modes, power savings can be achieved relative to the connected mode, with the inactive mode providing the most power saving. Further, within the connected mode, NR systems may support discontinuous reception (DRX) for additional power saving. During an “on duration” of a DRX cycle, the UE wakes up and monitors a physical downlink control channel (PDCCH) search space (SS) in a slot for downlink control inf