US-12621775-B2 - Method and apparatus for power saving enhancements with a wake-up signal for a dual-radio system

Abstract

Various solutions for power saving enhancements with a wake-up signal for a dual-radio system are described. An apparatus may configure a main radio of the apparatus to enter a sleep mode and a secondary radio of the apparatus to be in an active mode. The apparatus may receive, via the secondary radio, a first signal from a network node. The apparatus may apply the first signal for at least one of: a time or frequency synchronization with the network node; an indication of whether to wake up the main radio from the sleep mode; and a signal quality measurement.

Inventors

• Yi-Ju Liao
• Wei-De Wu

Assignees

• MEDIATEK INC.

Dates

Publication Date

20260505

Application Date

20230330

Claims (18)

1. 1 . A method, comprising: configuring, by a processor of an apparatus, a main radio of the apparatus to enter a sleep mode and a secondary radio of the apparatus to be in an active mode; receiving, via the secondary radio, a first signal from a network node; applying, by the processor, the first signal for at least one of: a time or frequency synchronization with the network node; an indication of whether to wake up the main radio from the sleep mode; and a signal quality measurement; and reporting, via the main radio, beam information to the network node when the apparatus is operating in a radio resource control (RRC) inactive state, wherein the beam information indicates a selected beam, and the first signal is transmitted to the apparatus at a direction of the selected beam.
2. 2 . The method of claim 1 , wherein the secondary radio is a low-power receiver, and the first signal is in a specific waveform that the low-power receiver is capable of processing.
3. 3 . The method of claim 1 , wherein the signal quality measurement comprises at least one of: a radio resources management (RRM) measurement; a radio link monitoring (RLM) measurement; and a beam failure detection (BFD) measurement.
4. 4 . The method of claim 3 , wherein the RRM measurement is performed for at least one of a serving cell and a neighboring cell, and the first signal comprises information for cell recognition when the RRM measurement is performed for both the serving cell and the neighboring cell.
5. 5 . The method of claim 1 , wherein the signal quality measurement is performed via the secondary radio based on the first signal, or is performed via the main radio when a signal quality of the first signal is below a threshold.
6. 6 . The method of claim 1 , further comprising: measuring, via the main radio, one or more synchronization signal blocks (SSBs) for beam selection; wherein the beam information comprises an index of one of the one or more SSBs with a strongest reference signal receiving power (RSRP).
7. 7 . The method of claim 1 , wherein the beam information is delivered based on an association between an SSB and a physical uplink shared channel (PUSCH) occasion.
8. 8 . The method of claim 6 , wherein measuring the one or more SSBs is performed periodically or only when the main radio is woken up from the sleep mode.
9. 9 . The method of claim 6 , wherein measuring the one or more SSBs is performed when a signal strength of the first signal is below a threshold.
10. 10 . The method of claim 1 , further comprising: receiving, via the secondary radio, a second signal from the network node, wherein the second signal comprises a beacon or a secondary synchronization signal (SSS) only.
11. 11 . The method of claim 10 , further comprising: measuring, via the main radio, one or more synchronization signal blocks (SSBs) for beam selection when a signal strength of the second signal is below a threshold; wherein the second signal is transmitted to the apparatus at the direction of the selected beam.
12. 12 . The method of claim 10 , wherein the second signal is transmitted to the apparatus in a beam sweeping manner to assist the apparatus with beam selection.
13. 13 . The method of claim 1 , wherein the first signal is transmitted to the apparatus in a beam sweeping manner or in a repetition manner when the apparatus is operating in an RRC idle state.
14. 14 . An apparatus, comprising: a transceiver which, during operation, wirelessly communicates with a network node of a wireless network, wherein the transceiver comprises a main radio and a secondary radio; and a processor communicatively coupled to the transceiver such that, during operation, the processor performs operations comprising: configuring the main radio to enter a sleep mode and the secondary radio to be in an active mode; receiving, via the secondary radio, a first signal from the network node; and applying the first signal for at least one of: a time or frequency synchronization with the network node; an indication of whether to wake up the main radio from the sleep mode; and a signal quality measurement; and reporting, via the main radio, beam information to the network node when the apparatus is operating in a radio resource control (RRC) inactive state, wherein the beam information indicates a select beam, and the first signal is transmitted to the apparatus at a direction of the selected beam.
15. 15 . The apparatus of claim 14 , wherein the secondary radio is a low-power receiver, and the first signal is in a specific waveform that the low-power receiver is capable of processing.
16. 16 . The apparatus of claim 14 , wherein the signal quality measurement comprises at least one of: a radio resources management (RRM) measurement; a radio link monitoring (RLM) measurement; and a beam failure detection (BFD) measurement.
17. 17 . The apparatus of claim 16 , wherein the RRM measurement is performed for at least one of a serving cell and a neighboring cell, and the first signal comprises information for cell recognition when the RRM measurement is performed for both the serving cell and the neighboring cell.
18. 18 . The apparatus of claim 14 , wherein the signal quality measurement is performed via the secondary radio based on the first signal, or is performed via the main radio when a signal quality of the first signal is below a threshold.

Description

CROSS REFERENCE TO RELATED PATENT APPLICATION(S) The present disclosure claims the priority benefit of U.S. Provisional Patent Application No. 63/334,323, filed on 25 Apr. 2022. The contents of aforementioned application are herein incorporated by reference in their entirety. TECHNICAL FIELD The present disclosure is generally related to mobile communications and, more particularly, to power saving enhancements with a wake-up signal for a dual-radio system. BACKGROUND Unless otherwise indicated herein, approaches described in this section are not prior art to the claims listed below and are not admitted as prior art by inclusion in this section. Power saving is one of the most important issues in any wireless communication system, and its importance is even more relevant for mobile devices, such as smartphones, which have limited amount of power source (e.g., battery) comparing to other type of devices, such as fixed wireless customer premise equipment (CPE) or devices mounted on a vehicle. This issue has become more important in 5th Generation (5G) New Radio (NR) since it has been observed that mobile devices (and even the base stations) tend to consume power more quickly when they are operating in 5G NR than in other legacy technologies (e.g., Long-Term Evolution (LTE)). To save power, a mobile device (or called a user equipment (UE)) may enter a radio resource control (RRC) idle or inactive state when there is no data traffic, but the UE has to monitor whether the wireless network is sending any paging message to it and it has to spend some energy to run this “monitoring” process. In the RRC idle/inactive state, the UE may stay in a sleep mode in a discontinuous reception (DRX) cycle. The UE may periodically wake up and monitor physical downlink control channel (PDCCH) in a DRX ON duration to check for the presence of a paging message. If the PDCCH indicates that a paging message is transmitted in a subframe, then the UE may demodulate the paging channel to see if the paging message is directed to it. Otherwise, the UE may stay in the sleep mode in a DRX OFF duration since the wireless network will not be transmitting any data to the UE in the DRX OFF duration. In 3rd Generation Partnership Project (3GPP) Release-16 for 5G NR, a wake-up signal (WUS) is introduced to enhance power saving for paging reception, by allowing the UE to only wake up in a DRX ON duration if a received WUS indicates the UE to wake up for the DRX ON duration. That is, the UE is allowed to skip a DRX ON duration if the received WUS indicates otherwise, so that the UE may stay in the sleep mode for a longer period of time. However, the R-16 WUS is used only for the purpose of data scheduling indication, and is designed for UEs with a single-radio architecture. The single radio is generally a power-hungry transceiver that is capable of complicated radio frequency (RF) signal processing, such as modulation and demodulation, and the receiver area size may not suit for compact devices or small form-factor devices, such as Internet-of-Things (IoT) devices or wearable devices. Therefore, a solution is sought to further improve the power saving issues. SUMMARY The following summary is illustrative only and is not intended to be limiting in any way. That is, the following summary is provided to introduce concepts, highlights, benefits and advantages of the novel and non-obvious techniques described herein. Select implementations are further described below in the detailed description. Thus, the following summary is not intended to identify essential features of the claimed subject matter, nor is it intended for use in determining the scope of the claimed subject matter. An objective of the present disclosure is to propose solutions or schemes that address the aforementioned issues pertaining to power saving enhancements with a wake-up signal for a dual-radio system. In one aspect, a method may involve an apparatus configuring a main radio of the apparatus to enter a sleep mode and a secondary radio of the apparatus to be in an active mode. The method may also involve the apparatus receiving, via the secondary radio, a first signal from a network node. The method may also involve the apparatus applying the first signal for at least one of: a time or frequency synchronization with the network node; an indication of whether to wake up the main radio from the sleep mode; and a signal quality measurement. In one aspect, an apparatus may comprise a transceiver which, during operation, wirelessly communicates with a network node of a wireless network, wherein the transceiver comprises a main radio and a secondary radio. The apparatus may also comprise a processor communicatively coupled to the transceiver. The processor, during operation, may perform operations comprising configuring the main radio to enter a sleep mode and the secondary radio to be in an active mode; receiving, via the secondary radio, a first signal from the network node; and ap