Method and apparatus for selecting operating modes having different reductive modes for low power wake-up signals

Abstract

The present disclosure relates to a method and apparatus for energy saving at a user equipment (UE) (20) side of a wireless communication system.

Description

Technical Field

[0001] This disclosure relates to wireless communication systems, and more specifically to methods and apparatus for energy saving on the user equipment (UE) side of a wireless communication system. Background Technology

[0002] To reduce power consumption, Extended Discontinuous Receiver (eDRX) has been introduced in 3GPP (3rd Generation Partnership Project) wireless communication systems. Essentially, in eDRX, the UE periodically enters sleep mode and remains dormant for a specified duration, during which time it does not monitor the Physical Downlink Control Channel (PDCCH). It is then woken up and remains awake for a specified duration to monitor the PDCCH for possible downlink data. The amount of power saved depends on the duration and frequency of the UE's sleep state. Naturally, the longer the UE remains dormant, the greater the power savings. However, increasing the sleep duration introduces increased latency, making eDRX unsuitable for latency-critical use cases.

[0003] To enhance energy efficiency without sacrificing latency in 5G or New Radio (NR) wireless communication systems, 3GPP plans to define a new architecture for UEs (see, for example, technical report TR 38.869).

[0004] Essentially, current UEs need to be woken up periodically once per eDRX cycle, which constitutes the main energy consumption during cycles without signaling or data traffic. Energy consumption could be significantly reduced if the UE could only be woken up when triggered (e.g., paging). As studied by 3GPP, this is achieved by providing the UE with both a main radio (MR) unit and a low-power wake-up receiver (LP-WUR).

[0005] Basically, the MR unit corresponds to the 5G NR wireless communication unit, and the LP-WUR corresponds to the wireless communication unit used for low-power monitoring of wake-up signals. Once a wake-up signal is detected, the LP-WUR can trigger the MR unit, which can then transition from a low-power state to an active state.

[0006] The active state corresponds to any state in which the MR unit exchanges data with the radio access network (RAN) of the wireless communication system without being triggered by the LP-WUR. Therefore, a woken-up MR unit is in the active state. Moreover, an MR unit that is in a dormant state but is periodically woken up without being triggered by the LP-WUR (e.g., eDRX) is also in the active state.

[0007] The low-power state corresponds to the state where the MR unit cannot exchange data with the RAN without being triggered by the LP-WUR. For example, the low-power state corresponds to the state where the MR unit is always asleep. However, since the MR unit does not need to be periodically woken up in the low-power state, the MR unit can sleep even more deeply than in the current UE and can even be turned off, because the LP-WUR can be used to enable the MR unit.

[0008] "Low power" means that the average power consumption of the MR unit in the low power state is lower (and preferably significantly lower, for example, ten times or even a hundred times lower) than the average power consumption of the MR unit in the active state.

[0009] A "low-power" wake-up receiver means that the LP-WUR is used to receive a wake-up signal when the MR unit is in a low-power state. Of course, the monitoring of the wake-up signal should be performed at low power, and therefore, the average power consumption of the LP-WUR should be lower than (and preferably significantly lower, for example, ten times or even a hundred times lower) the average power consumption of the MR unit when it is awake.

[0010] Therefore, power consumption is reduced by placing the MR unit in a low-power state (e.g., off). The MR unit does not need to be periodically woken up and can be woken up only when triggered by the LP-WUR. Since the LP-WUR can continuously or at least frequently monitor the wake-up signal, the MR unit can be woken up by the LP-WUR at any time, thereby reducing latency compared to, for example, eDRX.

[0011] While the specific details of the LP-WUR and the wake-up signal remain to be defined, the fact that the LP-WUR should be able to detect the wake-up signal with low power consumption implies that, for a given base station (BS) of the RAN, the coverage achievable by the wake-up signal monitored by the LP-WUR may be less than the coverage achievable by the PDCCH monitored by the MR unit (also known as the cell). Therefore, the LP-WUR of a UE at the cell edge may not always detect the wake-up signal sent by the BS. Consequently, if it is determined that the UE's received level of the wake-up signal will be too low, it is impossible to use the wake-up signal to trigger the MR unit. In this case, it is not possible, for example, to disable the MR unit. Summary of the Invention

[0012] This disclosure aims to improve this situation. In particular, this disclosure aims to address at least some of the limitations of the prior art discussed above. Specifically, this disclosure aims to provide a solution for enhancing the coverage of wake-up signals.

[0013] To this end, this disclosure proposes that the BS of a wireless communication system can use different repetition patterns to transmit wake-up signals. The different repetition patterns differ at least in the number of times the BS transmits the wake-up signal to the UE. For example, a first repetition pattern may include transmitting the wake-up signal only once (i.e., the wake-up signal is not repeated), and a second repetition pattern may include transmitting the wake-up signal two or more times (i.e., the wake-up signal is repeated one or more times). Increasing the number of times the BS transmits the wake-up signal increases the probability that the UE's LP-WUR will be able to detect the wake-up signal, thus increasing the coverage of the wake-up signal for the UE.

[0014] According to a first aspect, this disclosure relates to a method for exchanging data in a wireless communication system, the method being implemented by a wireless device of the wireless communication system, wherein the wireless device includes: a main radio (MR) unit configured to exchange data with a radio access network (RAN) of the wireless communication system; and a low-power wake-up receiver (LP-WUR) configured to detect a wake-up signal transmitted by the RAN, wherein the wireless device includes at least two operating modes, the at least two operating modes including a normal operating mode and a low-power operating mode, wherein:

[0015] - In the normal operating mode, the MR unit is in an active state.

[0016] - In the low-power operation mode, the MR unit is in a low-power state, and the LP-WUR is configured to trigger a transition to the normal operation mode in response to detecting a wake-up signal sent by the RAN.

[0017] Wherein, the RAN is adapted to send the wake-up signal by using multiple repetition patterns, and the method includes:

[0018] - Determine the repeating pattern among the plurality of repeating patterns that the RAN uses to send the wake-up signal.

[0019] - The estimated reception level represents the expected reception level of the LP-WUR for the wake-up signal transmitted by the RAN.

[0020] - The operating mode of the wireless device is selected based on the determined repetition pattern and the estimated received level.

[0021] In some embodiments, the method according to the first aspect may also include one or more of the following optional features, either individually or in any technically possible combination.

[0022] In some embodiments of the method according to the first aspect, the selection of the operating mode of the wireless device includes:

[0023] - In response to determining that the RAN uses a first repetition mode: if the estimated received level meets a first selection criterion, then the low-power operation mode is selected.

[0024] - In response to determining that the RAN uses a second repetition mode different from the first repetition mode: if the estimated received level satisfies the second selection criterion different from the first selection criterion, then the low-power operation mode is selected.

[0025] In some embodiments of the method according to the first aspect:

[0026] - If the estimated received level is greater than the first threshold, then the first selection criterion is met, and / or

[0027] - If the estimated received level is greater than a second threshold that is different from the first threshold, then the second selection criterion is satisfied.

[0028] In some embodiments of the method according to the first aspect, the first repetition pattern includes fewer repetitions of the wake-up signal than the second repetition pattern, and the first threshold is greater than the second threshold.

[0029] In some embodiments of the method according to the first aspect, one of the plurality of repeating patterns includes zero repetitions of the wake-up signal.

[0030] In some embodiments of the method according to the first aspect, the determination of the repetition pattern used by the RAN includes receiving an indication from the RAN.

[0031] In some embodiments of the method according to the first aspect, the instruction is received in system information broadcast by the RAN.

[0032] According to a second aspect, this disclosure relates to a wireless device including at least one memory and at least one processor, the at least one processor being configured to implement a method according to any one of the embodiments of the first aspect.

[0033] According to a third aspect, this disclosure relates to a user equipment (UE) that includes a wireless means according to any one of the embodiments of this disclosure.

[0034] According to a fourth aspect, this disclosure relates to a method for exchanging data in a wireless communication system, the method being implemented by a base station (BS) of a radio access network (RAN) of the wireless communication system, wherein the BS is configured to exchange data with a wireless device, the wireless device including a main radio (MR) unit and a low-power wake-up receiver (LP-WUR), wherein the LP-WUR is configured to detect a wake-up signal transmitted by the BS and, in response to detecting the wake-up signal transmitted by the BS, trigger a transition of the MR unit from a low-power state to an active state, wherein the method includes:

[0035] - Select the repetition mode for sending the wake-up signal from among multiple repetition modes.

[0036] - The wake-up signal is sent to the wireless device by using the selected repeat pattern.

[0037] In some embodiments, the method according to the fourth aspect may also include one or more of the following optional features, either individually or in any technically possible combination.

[0038] In some embodiments of the method according to the fourth aspect, the repeating pattern used is selected based on the load level of the BS and / or based on the energy consumption of the BS.

[0039] In some embodiments, the method according to the fourth aspect includes sending an indication to the wireless device of the repeating pattern being used.

[0040] In some embodiments of the method according to the fourth aspect, the indication is included in system information broadcast by the BS.

[0041] In some embodiments of the method according to the fourth aspect, the indication represents the load level of the BS.

[0042] According to a fifth aspect, this disclosure relates to a base station (BS) including at least one memory and at least one processor, the at least one processor being configured to implement a method according to any one of the embodiments of the fourth aspect.

[0043] According to a sixth aspect, this disclosure relates to a wireless communication system comprising at least one base station according to any one of the embodiments of this disclosure and at least one user equipment according to any one of the embodiments of this disclosure.

[0044] According to a seventh aspect, this disclosure relates to a computer program product comprising instructions that, when executed by at least one processor, configure the at least one processor to implement a method for exchanging data according to any of the embodiments of this disclosure. The computer program product may use any programming language and may be in the form of source code, object code, or any intermediate form between source code and object code, such as a partially compiled form, or any other desired form.

[0045] According to an eighth aspect, this disclosure relates to a (non-transitory) computer-readable storage medium comprising instructions that, when executed by at least one processor, configure the at least one processor to implement a method for sending control messages according to any one of the embodiments of this disclosure. Attached Figure Description

[0046] The invention will be better understood after reading the following description, which is given by way of non-limiting example and with reference to the accompanying drawings, which illustrate:

[0047] - Figure 1 : A schematic representation of an example of a wireless communication system including a BS and a UE.

[0048] - Figure 2 : A schematic representation of an example of a wireless device suitable for implementing one or more methods for exchanging data with a BS.

[0049] - Figure 3 : A schematic representation of an example of a BS suitable for implementing one or more methods for exchanging data with a wireless device.

[0050] - Figure 4 and Figure 5 : A flowchart illustrating an example of a method for exchanging data, implemented by a BS and a wireless device, respectively.

[0051] - Figure 6 and Figure 7 : Flowcharts illustrating other examples of methods for exchanging data, implemented by a BS and a wireless device, respectively.

[0052] - Figure 8 and Figure 9 : Flowcharts showing other examples of methods for sending control messages, implemented by a wireless device and a BS, respectively.

[0053] In these figures, the same reference numerals in each figure denote the same or similar elements. For clarity, unless otherwise explicitly stated, the elements shown are not drawn to scale. Detailed Implementation

[0054] The detailed description set forth below with reference to the accompanying drawings is intended as a description of various configurations and is not intended to represent the only configuration in which the concepts described herein can be practiced. The detailed description includes specific details for the purpose of providing a thorough understanding of the various concepts. However, it will be apparent to those skilled in the art that these concepts can be practiced without these specific details. For example, although 3GPP terms from, for example, 5G NR may be used in this disclosure to exemplify embodiments herein, this should not be considered as limiting the scope of this disclosure.

[0055] Generally, unless a different meaning is clearly given and / or implied from the context of the use of the term, all terms used herein will be interpreted according to their common meaning in the relevant art. Unless otherwise expressly stated, all references to a / an / said element, device, component, element, step, etc., will be interpreted openly as referring to at least one instance of said element, device, component, element, step, etc. Furthermore, the order of steps of any method disclosed herein, particularly in the figures, is provided for illustrative purposes only and is not intended to limit the disclosure. The disclosure may be applied where the same steps are performed in a different order and / or where steps are performed in parallel or in combination, unless a step is explicitly described as occurring after or before another step and / or where it is implied that a step must occur after or before another step. Moreover, in a figure, steps enclosed by dashed lines should be considered optional for the embodiment represented in that figure. Where appropriate, any feature of any of the embodiments disclosed herein may be applied to any other embodiment. Similarly, any advantage of any of the embodiments may be applied to any other embodiment, and vice versa. Other objects, features, and advantages of the appended embodiments will be apparent from the following description.

[0056] Figure 1 The illustration depicts an example of a wireless communication system, which may be, for example, a 5G NR wireless communication system. More specifically, Figure 1 The RAN represents a wireless communication system that exchanges data with the UE via radio signals. For example, the RAN can send data to the UE (downlink DL), such as data received from the core network (CN, not shown in the figure). The RAN can also receive data from the UE (uplink UL), which can be forwarded to the CN.

[0057] exist Figure 1In the example shown, the RAN includes one base station BS 30. Of course, the RAN can include more than one BS 30 to increase the coverage of the wireless communication system. Depending on the implemented wireless communication standard, each of these BSs can be called an NB, eNodeB (or eNB), gNodeB (or gNB, in the case of 5G NR wireless communication systems), access point, etc.

[0058] exist Figure 1 The example shown illustrates two UEs, 20-1 and 20-2. UEs 20-1 and 20-2 are located within the coverage area 31 (also known as the cell) of BS 30. The coverage area 31 of BS 30 essentially corresponds to the area where UEs can decode PDCCHs transmitted by BS 30.

[0059] Figure 2 An example of a wireless device 25 suitable for implementing any of the methods discussed in this disclosure at the UE is illustrated schematically. Essentially, the wireless device 25 corresponds to a device that provides wireless connectivity to a RAN (Radio Radio Network) of a wireless communication system and can be used to exchange data with said RAN.

[0060] This wireless device 25 can be included in the UE 20, such as Figure 2 As shown. UE 20 can be, for example, a cellular phone, wireless modem, wireless communication device, handheld device, laptop computer, etc. UE 20 can also be an Internet of Things (IoT) device, such as a wireless camera, smart sensor, smart meter, smart glasses, vehicle (manned or autonomous), GPS device, etc., or any other equipment that can run applications that require exchanging data with a remote receiver via wireless device 25.

[0061] like Figure 2 As shown, the wireless device 25 includes one or more processors 250 and one or more memories 251. The one or more processors 250 may include, for example, a central processing unit (CPU), a digital signal processor (DSP), a field-programmable gate array (FPGA), an application-specific integrated circuit (ASIC), etc. The one or more memories 251 may include any type of computer-readable volatile and non-volatile memory (hard disk, solid-state drive, optical disk, electronic storage, etc.). The one or more memories 251 may store a computer program product 252 in the form of a set of program code instructions to be executed by the one or more processors 250 to implement a method for exchanging data at the UE side according to any of the embodiments disclosed herein.

[0062] like Figure 2As shown, the wireless device 25 also includes a main radio MR unit 253 and a low-power wake-up signal receiver LP-WUR 254.

[0063] As discussed above, MR unit 253 corresponds to the main wireless communication unit of wireless device 25, which is used to exchange data with BS 30 of RAN using radio signals. MR unit 253 can implement one or more wireless communication protocols and can be, for example, a 3G, 4G, 5G, NR, WiFi, WiMax transceiver, etc. In a preferred embodiment, MR unit 253 corresponds to a 5G NR wireless communication unit.

[0064] The LP-WUR 254 corresponds to the secondary wireless communication unit of the wireless device 25, which is used to monitor a wake-up signal transmitted by the BS 30 of the RAN in a low-power manner. The wake-up signal can take any form that enables it to be detected in a low-power manner. Non-limiting examples of wake-up signals and the LP-WUR 254 are provided in technical report TR 38.869. It should be noted that in some examples, the wake-up signal can even be, for example, a specific 5G NR signal using a low-order modulation and coding scheme (MCS). In this case, the LP-WUR 254 may include components of the 5G NR wireless communication unit that are strictly required to detect such a specific 5G NR signal.

[0065] As discussed above, the primary purpose of the LP-WUR 254 is to monitor and detect wake-up signals (DL) sent by the RAN of a wireless communication system. Therefore, the LP-WUR 254 can be unidirectional only, i.e., having only receive (DL) capability and no transmit (UL) capability. However, in some examples, the LP-WUR 254 may also have transmit capability, allowing it to send (UL) data to the RAN.

[0066] The wireless device 25 is adapted to operate in at least two operating modes, including a normal operating mode and a low-power operating mode:

[0067] - In normal operating mode, MR unit 253 is in an active state.

[0068] - In low-power operation mode, MR unit 253 is in a low-power state, and LP-WUR 254 is configured to trigger a transition to normal operation mode in response to the detection of a wake-up signal sent by RAN.

[0069] As discussed above, the active state corresponds to any state in which MR unit 253 can exchange data with the RAN without being triggered by LP-WUR. Therefore, a woken-up MR unit 253 is in the active state. Moreover, MR unit 253 that is dormant but periodically woken up (e.g., eDRX) without being triggered by LP-WUR 254 is also in the active state.

[0070] The low-power state corresponds to the state in which MR unit 253 cannot exchange data with the RAN without being triggered by LP-WUR 254. For example, the low-power state corresponds to the state in which MR unit 253 is always in sleep mode. However, thanks to LP-WUR 254, MR unit 253 does not need to be periodically woken up in the low-power state, so MR unit 253 can be in a very deep sleep state and can even be turned off, because LP-WUR 254 can be used to turn on MR unit 253.

[0071] It should be noted that in some examples, the LP-WUR 254 can also be configured to trigger the MR unit 253 when other conditions are met. For example, the LP-WUR 254 can be configured to trigger the MR unit 253 if a predetermined timer has expired without a detected wake-up signal. This timer can be used to ensure that, for example, when the wireless device 25 has moved out of the wake-up signal's coverage area, the wireless device 25 can return to an active state. Of course, the duration of this timer should be long enough to ensure that the MR unit 253 remains in a low-power state for an extended period.

[0072] Figure 3 An example of a BS 30 is schematically shown that is suitable for implementing any of the methods discussed in this disclosure by the RAN.

[0073] like Figure 3 As shown, BS 30 includes one or more processors 300 and one or more memories 301. The one or more processors 300 may include, for example, a central processing unit (CPU), a digital signal processor (DSP), a field-programmable gate array (FPGA), an application-specific integrated circuit (ASIC), etc. The one or more memories 301 may include any type of computer-readable volatile and non-volatile memory (hard disk, solid-state drive, optical disk, electronic storage, etc.). The one or more memories 301 may store a computer program product 302 in the form of a set of program code instructions to be executed by the one or more processors 300 to implement the steps of a method for exchanging data at the RAN side according to any of the embodiments disclosed herein.

[0074] like Figure 3As shown, BS 30 also includes a wireless communication unit 303 configured to exchange data with UE 20 using radio signals, and more specifically with the MR unit 253 of the wireless device 25 included in these UEs 20. The wireless communication unit 303 may be, for example, a 3G, 4G, 5G, NR, WiFi, WiMax, or other transceivers. In a preferred embodiment, the wireless communication unit 303 of BS 30 corresponds to a 5G NR transceiver.

[0075] like Figure 3 As shown, BS 30 also includes a wake-up signal transmitter (WUT) 304, which is configured to send a wake-up signal to a UE having a wireless device 25 including an LP-WUR 254. Figure 3 In the example shown, WUT 304 is represented as separate from wireless communication unit 303. However, for example, if wireless communication unit 303 is a 5G NR transceiver and if the wake-up signal is a specific 5G NR signal, WUT 304 may also be included in wireless communication unit 303.

[0076] As discussed above regarding LP-WUR 254, the primary purpose of WUT 304 is to transmit (DL) wake-up signals. Therefore, WUT 304 can be unidirectional, meaning it only has transmit (DL) capability and no receive (UL) capability. However, in some examples, WUT 304 can also have receive capability, allowing it to receive (UL) data from UE 20's LP-WUR 254.

[0077] like Figure 3 As shown, BS 30 may further include a network communication unit 305 configured to exchange data with other base stations of the RAN and / or with the CN. The network communication unit 305 may support one or more suitable communication protocols, which may be wired (including fiber optic) and / or wireless.

[0078] The WUT 304 of BS 30 is adapted to send a wake-up signal to wireless device 25 using different repeat patterns.

[0079] As discussed above, the repetition patterns differ at least in the number of times the WUT 304 sends a wake-up signal to the wireless device 25. Therefore, different repetition patterns include at least a first repetition pattern and a second repetition pattern, wherein the wake-up signal is sent fewer times in the first repetition pattern than in the second repetition pattern. For example, the first repetition pattern may include sending the wake-up signal only once (i.e., the wake-up signal is not repeated), and the second repetition pattern may include sending the wake-up signal two or more times (i.e., the wake-up signal is repeated once or more). It should be noted that this disclosure is not limited to a specific method for repeating the wake-up signal, and any method for repeating the wake-up signal falls within the scope of this disclosure. For example, wake-up signals with different occurrence forms may be sent at different times and / or on different frequency channels and / or on different resource blocks.

[0080] As discussed above, increasing the number of times BS 30 sends a wake-up signal will increase the probability that LP-WUR 254 will be able to detect the wake-up signal (by, for example, using signal processing techniques known to the art, such as maximum ratio combining MRC).

[0081] Figure 1 The diagram schematically illustrates the coverage area 32-1 of the wake-up signal when using the first repeat mode and the coverage area 32-2 of the wake-up signal when using the second repeat mode. In this example, fewer wake-up signals are sent in the first repeat mode than in the second repeat mode, resulting in a wider coverage area 32-2 than 32-1. If the first repeat mode is used, UE 20-2, which is within coverage area 32-2 but not within coverage area 32-1, cannot use its LP-WUR 254 to trigger its MR unit 253. Conversely, in either the first or second repeat mode, UE 20-1, which is within both coverage areas 32-1 and 32-2, can use its LP-WUR 254 to trigger its MR unit 253.

[0082] Therefore, by increasing the number of times the BS 30 sends a wake-up signal, the BS enables more UEs to use their LP-WUR 254 to trigger their MR units 253.

[0083] Such multiple repetition patterns can be used in various ways, some of which will be described below. For example, BS 30 may decide to use the same repetition pattern from among multiple possible repetition patterns for all UEs within its PDCCH coverage area 31, or selectively adapt the repetition pattern used to each UE or UE group. Moreover, the repetition pattern used for a UE (or UE group) may be selected by BS 30 and / or the UE (or UE group) under consideration.

[0084] Figure 4A diagram illustrating the steps of an exemplary embodiment of a method 40 for exchanging data, implemented by BS 30. Figure 5 The diagram illustrates the corresponding steps of an exemplary embodiment of a method 50 for exchanging data implemented by the wireless device 25 of the UE 20.

[0085] like Figure 4 As shown, the method 40 for exchanging data includes step S40 whereby the BS 30 selects a repeating mode from among several possible repeating modes for sending a wake-up signal. In this example, the same selected repeating mode is considered in a non-limiting manner for all UEs 20 within the coverage area 31 of the BS 30. However, in other examples (some of which will be discussed below), a repeating mode specific to a given UE 20 or a given group of UEs 20 may also be selected. It is important to emphasize that the fact that the same repeating mode is used for all UEs 20 does not mean that the same wake-up signal is used for all UEs 20. In fact, the BS 30 may need to specifically wake up a given UE 20 or group of UEs such that the sent wake-up signal should be ignored by other UEs not intended to be woken up. Using the same repeating mode simply means that the wake-up signal is repeated the same number of times, regardless of which UE 20 is to be woken up.

[0086] When BS 30 needs to wake up UE 20 (or group of UE 20) having a wireless device 25 in a low-power operation mode, BS 30 sends a wake-up signal (step S41) to that specific UE 20 (or group of UE 20) by using a selected repeating mode.

[0087] BS 30 can select a repetition mode from multiple repetition modes, for example, based on one or more parameters. Since increasing the number of times wake-up signals are sent increases the number of UEs 20 that may be able to wake up their MR units 253 by relying on their LP-WUR 254, it may be advantageous in some cases to select the highest possible number of repetitions of the wake-up signals.

[0088] In the example considered herein, where the same selected repetition mode is used for all UEs 20 within the coverage area 31 of BS 30, the selection can use parameters that can be evaluated by BS 30 without receiving information from UEs 20. However, in other examples, information received from UEs 20 may also be considered during the repetition mode selection process.

[0089] For example, the repetition mode can be selected based on the load level of BS 30. The load level of BS 30 can be any parameter representing the amount of data that BS 30 may have to handle due to UE 20 within its coverage area 31. For example, if the load level of BS 30 is low, it can decide to select a repetition mode with more repetitions of wake-up signals, and if its load level is high, it can select a repetition mode with fewer repetitions (or no repetitions at all). For example, the load level of BS 30 can correspond to the total number of UE 20 within the coverage area 31 of BS 30, or to the total amount of data to be sent to UEs within its coverage area 31, or to the number of high-priority UEs 20 within its coverage area 31, or to the total amount of resources that need to be scheduled for high-priority UEs 20 within its coverage area 31, etc. For example, if multiple possible repetition modes include a first repetition mode with no repetition (i.e., the wake-up signal is sent only once) and a second repetition mode with the wake-up signal being repeated at least once (i.e., the wake-up signal is sent at least twice), then BS 30 can select the first repetition mode when the load level is high (e.g., above a predetermined threshold), and BS 30 can enable repetition by selecting the second repetition mode when the load level is low (e.g., below a predetermined threshold).

[0090] Alternatively, or in combination thereof, the repetition mode can be selected based on the power consumption of the BS 30. For example, if the BS 30 wants to temporarily reduce its power consumption, it can select a repetition mode with fewer repetitions (or no repetitions at all). Conversely, if there is no constraint on the power consumption of the BS 30, the BS can select a repetition mode with more repetitions of the wake-up signal.

[0091] It should be noted that BS 30 is not necessarily required to notify UE 20 of the selected repetition mode. For example, each UE 20 can search for the wake-up signal by assuming that it is sent using the repetition mode with the maximum number of repetitions among a plurality of possible repetition modes.

[0092] However, in some examples, and such as Figure 4As shown in the non-limiting example, the method 40 for exchanging data may include step S42 of sending an indication of a selected repeating mode to each UE 20. In the non-limiting example considered herein of using the same selected repeating mode for all UEs 20 within the coverage area of ​​BS 30, the indication may, for example, be included in system information broadcast to all UEs 20. Including the indication in system information broadcast to all UEs 20 is advantageous because the indication can be received by all UEs (including UEs 20 in an RRC idle / inactive state) regardless of the Radio Resource Control (RRC) state of all UEs 20. However, other types of messages may also be used to send the indication of the selected repeating mode to the UEs 20. For example, the indication of the selected repeating mode may be sent by using the wireless communication unit 303 of BS 30, and thus received by the UEs 20 that make their wireless devices 25 use the normal operating mode (MR unit 253 is active) before transitioning to a low-power operating mode. However, in other examples, the indication of the selected repetition mode can be sent by the WUT 304 using BS 30, and thus can even be received by the LP-WUR 254 of UE 20 which puts their radio devices 25 into a low-power operation mode.

[0093] The indication of the selected repetition mode can use any suitable format. For example, the indication can correspond to an identifier indicating the selected repetition mode or a bit vector indicating the number of times the wake-up signal is repeated. For example, if multiple possible repetition modes include a first repetition mode without repetition and a second repetition mode is a repetition mode in which the wake-up signal is repeated at least once, the indication can include a bit vector having a single bit for indicating whether the repetition of the wake-up signal has occurred. According to another non-limiting example, if BS 30 selects the repetition mode based on its load level, the transmitted indication can represent the load level of BS 30, according to which UE 20 can determine the repetition mode selected by BS 30 by applying the same selection procedure as BS 30.

[0094] As discussed above, Figure 5 The diagram illustrates corresponding steps of an exemplary embodiment of a method 50 for exchanging data, which can be implemented in BS 30. Figure 4 The method 40 for exchanging data shown is implemented by the wireless device 25 of UE 20.

[0095] like Figure 5As shown, the method 50 for exchanging data includes step S50 of determining a repeating pattern used by the BS 30 to send a wake-up signal. As discussed above, the wireless device 25 may determine the repeating pattern used by the BS 30, for example, based on an instruction received from the BS 30.

[0096] like Figure 5 As shown, the method 50 for exchanging data further includes step S53, which searches for a wake-up signal sent by BS 30 based on a repeating pattern determined during step S50 when the wireless device 25 of UE 20 is in a low-power operation mode.

[0097] However, Figure 5 The non-limiting example shown focuses on how wireless device 25 can determine whether it can enter a low-power / low-power operating mode. Indeed, as discussed above, the coverage area of ​​the wake-up signal can be less than the PDCCH coverage area 31 of BS 30, and therefore, if wireless device 25 is not within the coverage area of ​​the wake-up signal, it should not be placed in a low-power operating mode. Furthermore, the coverage area of ​​the wake-up signal is modified by the repeating pattern used by BS 30, so wireless device 25 can use the repeating pattern determined during step S50 to adjust its behavior regarding monitoring the wake-up signal.

[0098] like Figure 5 As shown in the non-limiting example, method 50 includes step S51 of estimating the receive level representing the expected receive level of the wake-up signal sent by BS 30 to LP-WUR 254.

[0099] Essentially, the estimated received level corresponds to any parameter that can be used to predict, for each possible repetition pattern, whether the wireless device 25 will be within the coverage area of ​​a wake-up signal transmitted by the BS 30 using the considered repetition pattern. In fact, any measurement, including a measurement of the path loss between the BS 30 and the wireless device 25, can be considered to represent the expected received level of the LP-WUR 254 for the wake-up signal transmitted by the BS 30, since the path loss depends on the distance between the BS 30 and the LP-WUR 254. Therefore, the estimated received level can be determined, for example, by measuring any radio signal transmitted by the BS 30. For example, the estimated received level can be determined by measuring a reference signal transmitted by the wireless communication unit 303 of the BS 30 (measured by the MR unit 253) or a reference signal transmitted by the WUT 304 of the BS 30 (measured by the MR unit 253 or by the LP-WUR 254). In other examples, the estimated received level can also be determined based on measurements of the wake-up signal transmitted by the BS 30. For example, the estimated received level can be determined based on the following:

[0100] - The received level measured by the LP-WUR 254 of wireless device 25 for a wake-up signal sent from BS 30 to another wireless device; and / or

[0101] - The received level measured by the LP-WUR 254 of the wireless device 25 for the wake-up signal addressed to the wireless device 25 received during a previous cycle when the wireless device 25 is in a low-power operation mode.

[0102] For example, the estimated received level determined based on measurements of the reference signal transmitted by BS 30 can correspond to the reference signal received power RSRP and / or the reference signal received quality RSRQ of the reference signal as defined in the 3GPP specifications.

[0103] like Figure 5 As shown in the non-limiting example, the method 50 for exchanging data includes step S52 of selecting an operating mode of the wireless device 25 based on a determined repetition pattern (in step S50) and an estimated received level (in step S51). In fact, since the wireless device 25 knows the repetition pattern used by BS 30 to transmit a wake-up signal and the expected received level of that wake-up signal, the wireless device can assess whether it is within the coverage area of ​​the wake-up signal. If, based on the determined repetition pattern and the estimated received level, the wireless device 25 determines that it may be outside the coverage area of ​​the wake-up signal (…),… Figure 5 If the wireless device selects a normal operating mode (as indicated by reference numeral S52b in the accompanying drawings), then the wireless device selects a normal operating mode. Conversely, if the wireless device 25 determines that it may be within the coverage area of ​​the wake-up signal (…), the wireless device selects a normal operating mode. Figure 5 If the reference numeral S52a in the attached figure is used, then the wireless device selects a low-power operation mode.

[0104] For example, it is assumed in a non-limiting manner that multiple possible repetition modes include a first repetition mode and a second repetition mode, wherein the first repetition mode includes fewer repetitions of the wake-up signal than the second repetition mode. In this case, if the wireless device 25 has determined that the BS 30 uses the first repetition mode, the wireless device can evaluate whether the estimated received level meets a predetermined first selection criterion. If the first selection criterion is met (and correspondingly not met), the wireless device 25 selects a low-power operation mode (and correspondingly, a normal operation mode). If the wireless device 25 has determined that the BS 30 uses the second repetition mode, the wireless device can evaluate whether the estimated received level meets a predetermined second selection criterion different from the first selection criterion. If the second selection criterion is met (and correspondingly not met), the wireless device 25 selects a low-power operation mode (and correspondingly, a normal operation mode).

[0105] For example, if the estimated received level is greater than a first threshold, a first selection criterion is satisfied, and / or if the estimated received level is greater than a second threshold different from the first threshold, a second selection criterion is satisfied. Essentially, the first threshold represents a first minimum received level above which a wake-up signal can be detected when using a first repetition mode, and the second threshold represents a second minimum received level above which a wake-up signal can be detected when using a second repetition mode. Because the second repetition mode includes more repetitions of the wake-up signal than the first repetition mode, a wake-up signal can be detected at a lower received level when using the second repetition mode than when using the first mode, making the first threshold typically greater than the second threshold. The corresponding values ​​of the first and second thresholds can be, for example, predefined (e.g., specified by a standard or through calibration of the wireless device), or they can be, for example, received from BS 30 (e.g., included in system information broadcast by BS 30 or in messages dedicated to the wireless device 25).

[0106] Figure 6 A diagram illustrating the steps of an exemplary embodiment of a method 60 for exchanging data, implemented by BS 30. Figure 7 The diagram illustrates the corresponding steps of an exemplary embodiment of a method 70 for exchanging data implemented by the wireless device 25 of the UE 20.

[0107] like Figure 6 As shown, the method 60 for exchanging data includes step S60 whereby the BS 30 selects a repeating mode from a plurality of possible repeating modes for sending a wake-up signal. In this example, it can be considered in a non-limiting manner that the BS 30 may adjust the repeating mode for each UE 20 or group of UE 20. In other words, the BS 30 may use different repeating modes from a plurality of possible repeating modes for different UE 20.

[0108] When BS 30 needs to wake up UE 20 (or group of UE 20) having a wireless device 25 in a low-power operation mode, BS 30 sends a wake-up signal (step S61) to the specific UE 20 (or group of UE 20) by using a repeating mode selected for that UE 20 (or group of UE 20).

[0109] As discussed above regarding step S42, BS 30 is not necessarily required to notify UE 20 (or the group of UE 20) of the selected repeat mode. However, in some examples, and as... Figure 6As shown in the non-limiting example, the method 60 for exchanging data may include step S62 of sending an indication to a specific UE 20 (or group of UEs 20) of a repeating mode selected for that UE 20 (or group of UEs 20). All that has been described above regarding, for example, step S42 with respect to the indication, is similarly applicable to... Figure 6 and Figure 7 The example shown.

[0110] BS 30 can select a repeating mode from multiple repeating modes, for example, based on one or more parameters. In the example of a repeating mode customized for each UE 20 (or group of UE 20s) considered herein, the repeating mode can be selected based on information received from that UE 20 (or group of UE 20s). Non-limiting examples of information received from UE 20s that can be used in the repeating mode selection process are discussed below.

[0111] exist Figure 6 In a non-limiting example, the method 60 for exchanging data includes step S63 of receiving an estimated received level from the radio device 25 of the UE 20, and the repetition mode for the UE 20 is selected during step S60 based on the received estimated received level. All that has been described above regarding, for example, step S51 for estimating the received level, similarly applies. Figure 6 and Figure 7 The example shown. For instance, the estimated received level may correspond to RSRP and / or RSRQ.

[0112] By using the estimated receive level provided by UE 20 (which represents the expected receive level of LP-WUR 254 of UE 20 for a wake-up signal transmitted by BS 30), BS 30 can assess the coverage required for LP-WUR 254 of UE 20 to detect the wake-up signal. If the estimated receive level is high, BS 30 can reduce the number of times a wake-up signal is transmitted to UE 20 (and may disable repetition for UE 20). Conversely, if the estimated receive level is low, BS 30 can increase the number of times a wake-up signal is transmitted to UE 20 to increase the coverage of the wake-up signal. In some cases, the estimated receive level may meet a predetermined out-of-range criterion, i.e., the estimated receive level may be too low for LP-WUR 254 of UE 20 to detect the wake-up signal. In this case, BS 30 may decide to disable the transmission of the wake-up signal for that particular UE 20 during selection step S60, so that the radio device 25 of the UE should remain in normal operating mode.

[0113] For example, during selection step S60, BS 30 may use a predetermined mapping between multiple possible repetition patterns and their respective associated received levels. Table 1 below provides a non-limiting example of such a mapping.

[0114] Table 1

[0115] RSRP / RSRQ Repeating pattern identifier RL1 RP1 RL2 RP2 RL3 RP3 RL4 RP4 RL5 RP5

[0116] In the examples in Table 1, the received levels are considered to correspond to RSRP or RSRQ, and the received levels RL1 to RL5 satisfy:

[0117] RL1 > RL2 > RL3 > RL4 > RL5

[0118] Repeating patterns RP1 to RP5 satisfy:

[0119] - Repeat mode RP1 has the fewest repetitions (there may be no repetitions, where the wake-up signal is sent only once).

[0120] - Repeating pattern RP2 has more repetitions (and greater coverage) than repeating pattern RP1.

[0121] - Repeating mode RP3 has more repetitions (and greater coverage) than repeating mode RP2.

[0122] - Repeating mode RP4 has more repetitions (and greater coverage) than repeating mode RP3.

[0123] - Repeat mode RP5 has more repetitions (and greater coverage) than repeat mode RP4.

[0124] For example, a wake-up signal could be:

[0125] - In repeat mode RP1, it is sent only once (no repetition).

[0126] - It is sent twice in repeat mode RP2 (one repeat).

[0127] - It is sent four times (three repetitions) in repeat mode RP3.

[0128] - Sent six times (five repetitions) in repeat mode RP4.

[0129] - It is sent eight times (seven repetitions) in repeat mode RP5.

[0130] In the example in Table 1, if the estimated received level received from UE 20 is greater than RL1, BS 30 selects repetition mode RP1. If the estimated received level is lower than RL1 but higher than RL2, BS 30 selects repetition mode RP2. If the estimated received level is lower than RL2 but higher than RL3, BS 30 selects repetition mode RP3. If the estimated received level is lower than RL3 but higher than RL4, BS 30 selects repetition mode RP4. If the estimated received level is lower than RL4 but higher than RL5, BS 30 selects repetition mode RP5. If the estimated received level is lower than RL5, the out-of-range criterion is met, and BS 30 disables the transmission of wake-up signals for that specific UE 20; therefore, the UE's radio device 25 should remain in normal operating mode.

[0131] During the selection step S60, the base station 30 may also use other parameters alternatively or in combination with the estimated received level.

[0132] exist Figure 6 In a non-limiting example, the method 60 for exchanging data includes a step S64 of receiving auxiliary information from the radio device 25 of the UE 20, and the repeating mode for the UE 20 is selected during step S60 based on the received auxiliary information. The auxiliary information can be any information that can be related to selecting a repeating mode for the radio device 25 of the UE 20. For example, the BS 30 can receive from the radio device 25 a mobility state indicating whether the UE 20 is non-stationary (moving) or stationary (not moving). For example, if the UE 20 is non-stationary, the BS 30 can decide to disable the transmission of a wake-up signal for the UE 20, or the BS can decide to use a repeating mode with the maximum number of repetitions of the wake-up signal (i.e., the repeating mode with the widest coverage) to address the fact that even if the UE 20 is currently close to the BS 30, it may move away from the BS 30. Moreover, if the mobility state indicates that the UE 20 is moving away from the BS 30, the BS 30 can decide to disable the transmission of a wake-up signal for the UE 20. Alternatively, or in combination thereof, the wireless device 25 may transmit supplementary information including information about the future UL service characteristics of the UE 20. For example, if the received future UL service characteristics indicate that the UE 20's UL service may be important in the short term, the BS 30 may decide to disable the transmission of a wake-up signal for that UE 20.

[0133] It should be noted that in other examples, the BS 30 may use other parameters besides the information received from the UE 20. For example, the BS 30 may also select a repetition mode based on its load level and / or its power consumption. For instance, the BS 30 may decide to customize a repetition mode for the UE 20 within its coverage area 31 only when its load level is low and / or its power consumption is low. If the BS 30 has a high load level and / or high power consumption, the BS may decide to select the same repetition mode for all UE 20 (e.g., a repetition mode with the fewest repetitions).

[0134] As indicated above, BS 30 can also select a repetition mode for the group of UEs 20. For example, the group of UEs 20 may correspond to UEs 20 that need to be woken up simultaneously, and the same wake-up signal can be sent as a multicast signal to the group of UEs. In this case, BS 30 can select a repetition mode that enables all UEs 20 to detect the wake-up signal, for example, based on an estimated reception level received from these UEs 20. According to another example, BS 30 can divide the group into subgroups of UEs 20 with similar estimated reception levels, and the BS can adjust the repetition mode for each UE subgroup (so that if UEs 20 within a subgroup need to be woken up simultaneously, a wake-up signal can be sent as a multicast signal to each subgroup by using the corresponding repetition mode).

[0135] During the transmission step S62, the instruction sent to the UE 20 may include, for example, an identifier of the repeating mode selected for the UE 20 or the number of repetitions or occurrences of the wake-up signal.

[0136] For example, if BS 30 has selected repetition mode RP3, the indication may include identifier RP3. The transmitted identifier may, for example, correspond to the index of the selected repetition mode among multiple repetition modes. For example, the index of repetition mode RP1 may be '0', the index of repetition mode RP2 may be '1', the index of repetition mode RP3 may be '2', the index of repetition mode RP4 may be '3', and the index of repetition mode RP5 may be '4'. Based on the received repetition mode identifier, the radio device 25 of UE 20 may, for example, determine the corresponding number of times the wake-up signal is transmitted by using a pre-configured mapping between the multiple repetition mode identifiers and their corresponding number of repetitions or occurrences of the wake-up signal. Table 2 below provides a non-limiting example of the mapping between the multiple repetition mode identifiers and their corresponding number of repetitions of the wake-up signal for the repetition modes RP1 to RP5 discussed above:

[0137] Table 2

[0138] Repeating pattern identifier Number of repetitions RP1 0 RP2 1 RP3 3 RP4 5 RP5 7

[0139] The mapping between multiple repeating pattern identifiers and their corresponding number of repetitions or occurrences of the wake-up signal is pre-configured at wireless device 25. This mapping may be, for example, predefined (e.g., specified by a standard or through calibration of the wireless device), or it may be transmitted, for example, by BS 30. In the latter case, the mapping may be included, for example, in system information broadcast by BS 30 or in messages dedicated to wireless device 25 (such as RRC messages (e.g., RRC reconfiguration messages)).

[0140] According to another example, if BS 30 has selected repetition mode RP3, the indication may include the number of times the wake-up signal is repeated in the selected repetition mode (i.e., three repetitions for RP3) or the equivalent number of times the wake-up signal appears in the selected repetition mode (i.e., four appearances for RP3).

[0141] The indication of the selected repeat mode sent to the corresponding specific UE 20 (the indication may be an indication of sending a disable wake-up signal) can use any type of suitable signaling. For example, the indication can be included in an RRC message sent to the specific UE 20 (such as an RRC reconfiguration message (if, for example, the radio device 25 is in RRC connected mode)), or the indication can be sent to the specific UE 20 via L1 signaling and / or L2 signaling. For example, L1 signaling corresponds to the use of the Physical Downlink Control Channel (PDCCH). For example, L2 signaling corresponds to the use of the Media Access Control (MAC) control element (CE).

[0142] In some cases, sending an instruction to the radio device 25 of the UE 20 under consideration may include sending a configuration message along with the instruction or in a separate message, the configuration message including a more detailed description of the repetition pattern that the BS 30 will use for the UE 20. For example, the more detailed description may include a description of the physical parameters of the repetition pattern, such as, for example, the time interval between two consecutive occurrences of a wake-up signal in the repetition pattern, the frequency channel used for the corresponding occurrence, etc. Such a more detailed description, if available, can be used to assist / support the radio device 25 of the UE 20 in searching for a wake-up signal. However, it should be noted that such a description of the physical parameters may not be necessary for the UE 20 to search for a wake-up signal. For example, knowing the number of times a wake-up signal is sent may be sufficient for the radio device 25 to search for a wake-up signal. According to another example, the physical parameters of each possible repetition pattern (e.g., the time interval between two consecutive occurrences) may be pre-configured at the radio device 25, for example, predefined (e.g., specified by a standard or through the calibration of the radio device), or broadcast by the BS 30 in system information.

[0143] In some cases, the method 60 for exchanging data may also include one or more of the following:

[0144] - For example, an activation message is sent to UE 20 via L1 / L2 signaling, indicating that the use of the repeat mode is activated by BS 30: This can be used, for example, in cases where the repeat mode is not activated immediately once selected, and can be used to notify radio device 25 that it can enter a low-power operation mode.

[0145] - For example, a deactivation message is sent to UE 20 via L1 / L2 signaling, indicating that the use of the repeating mode indicated by the notification has been disabled by BS 30: This can be used, for example, when the load level and / or power consumption of BS 30 has increased, or as an acknowledgment message sent to UE 20 that has notified BS 30 that it has switched from low-power operating mode to normal operating mode.

[0146] - For example, a low-power disable message is sent to UE 20 via L1 / L2 signaling to disable the RAN's transmission of wake-up signals for UE 20: This can be used, for example, when the load level and / or power consumption of BS 30 has increased.

[0147] As discussed above, Figure 7 The diagram illustrates corresponding steps of an exemplary embodiment of a method 70 for exchanging data, which can be implemented in BS 30. Figure 6 The method 60 for exchanging data shown is implemented by the wireless device 25 of UE 20.

[0148] like Figure 7 As shown, the method 50 for exchanging data includes a step S70 of determining a repetition mode (selected during step S60) chosen by the BS 30 to send a wake-up signal for the wireless device 25. As discussed above, the wireless device 25 may determine the repetition mode used by the BS 30, for example, based on an instruction received from the BS 30.

[0149] like Figure 7 As shown, the method 50 for exchanging data also includes step S71, which searches for a wake-up signal sent by BS 30 based on a repeating pattern determined during step S70 when the wireless device 25 of UE 20 is in a low-power operation mode.

[0150] exist Figure 7 In the non-limiting example shown, the radio device 25 of UE 20 sends information to BS 30 that enables BS 30 to adjust the repetition mode. As discussed above, this information may include, for example, estimated received levels and / or auxiliary information.

[0151] exist Figure 7 In the non-limiting example shown, the information includes an estimated received level, and the method 70 for exchanging data includes:

[0152] - Step S72, which estimates the expected received level of the LP-WUR 254 in response to the wake-up signal.

[0153] - Step S73: Send the estimated received level to BS 30.

[0154] All the content described above regarding step S51 for estimating the received level applies similarly to step S72. For example, the estimated received level may correspond to RSRP and / or RSRQ and may be sent in the measurement report.

[0155] exist Figure 7 In the non-limiting example shown, the information also includes auxiliary information (e.g., mobility status, future UL business characteristics, etc.), and the method 70 for exchanging data includes step S74 of sending auxiliary information to BS 30.

[0156] Figure 8 The figure illustrates the steps of an exemplary embodiment of a method 80 for exchanging data implemented by the wireless device 25 of the UE 20. Figure 9 The diagram illustrates the corresponding steps of an exemplary embodiment of a method 90 for exchanging data implemented by BS 30.

[0157] exist Figure 8 and Figure 9 In the examples shown, the repetition pattern used to send a wake-up signal to a specific UE 20 (or group of UE 20) is adjusted for that specific UE 20 (or group of UE 20). However, in these examples, UE 20 selects the repetition pattern that BS 30 is to use to send the wake-up signal to that UE 20.

[0158] like Figure 8 As shown, the method 80 for exchanging data includes:

[0159] - Step S80, in which the wireless device 25 of UE 20 selects a repeating mode from multiple possible repeating modes for sending a wake-up signal, and

[0160] - Step S81: Sending an instruction to BS 30 for the selected repeating mode to be used by BS 30 to send a wake-up signal to the UE 20.

[0161] The wireless device 25 can select a repetition mode from multiple repetition modes, for example, based on one or more parameters. For instance, the wireless device 25 can select a repetition mode based on mobility status. For example, if the UE 20 is not stationary, the wireless device 25 can decide to disable monitoring of the wake-up signal, or the wireless device can decide to select the repetition mode with the maximum number of repetitions of the wake-up signal to address the fact that even if the UE 20 is currently close to the BS 30, it may move away from the BS 30. Furthermore, if the UE 20 is moving away from the BS 30, the wireless device 25 can decide to disable monitoring of the wake-up signal.

[0162] exist Figure 8 In a non-limiting example, the method 80 for exchanging data includes step S82, whereby the wireless device 25 estimates a receive level representing the expected receive level of the LP-WUR 254 for a wake-up signal, and the estimated receive level is used for the selection of a repeat mode. All that has been described above with respect to, for example, step S51 for estimating the receive level, similarly applies to step S82. For example, the estimated receive level may correspond to RSRP and / or RSRQ.

[0163] By using an estimated reception level representing the expected reception level of the wake-up signal transmitted by the BS 30 to the LP-WUR 254 of the UE 20, the radio device 25 can assess the coverage required for the LP-WUR 254 of the radio device to detect the wake-up signal. If the estimated reception level is high, the radio device 25 can reduce the number of times the wake-up signal should be transmitted to the UE 20 (and may disable repetition for the UE 20). Conversely, if the estimated reception level is low, the radio device can increase the number of times the wake-up signal should be transmitted to the UE 20 to increase the coverage of the wake-up signal. In some cases, the estimated reception level may meet a predetermined out-of-range criterion, i.e., the estimated reception level may be too low for the LP-WUR 254 of the UE 20 to detect the wake-up signal. In this case, the radio device 25 may decide during selection step S80 to disable monitoring of the wake-up signal for that particular UE 20 (and remain in normal operating mode), and may inform the BS 30, for example, in an instruction transmitted during step S81, that it is impossible to receive the wake-up signal at the radio device.

[0164] For example, during selection step S80, the wireless device may use a predetermined mapping between multiple possible repetition patterns and their respective associated receive levels. Table 1 above provides a non-limiting example of such a mapping, which may be used by the wireless device 25, and the selection process described with respect to Table 1 may be similarly applied by the wireless device 25. This mapping between the multiple repetition patterns and their respective associated receive levels, if used, is pre-configured at the wireless device 25. For example, the mapping may be predefined (e.g., specified by a standard or through calibration of the wireless device 25), or the mapping may be received, for example, from the BS 30. In the latter case, the mapping may be included, for example, in system information broadcast by the BS 30 or received in a message dedicated to the wireless device 25 (such as an RRC message (e.g., an RRC release message)).

[0165] The indication of the selected repetition mode sent to BS 30 during step S81 (the indication may be an indication to disable monitoring of the wake-up signal, for example, due to meeting an out-of-range criterion) may use any type of suitable signaling.

[0166] For example, such an indication can be sent to BS 30 using a small data transmission SDT procedure, such as a pre-configured SDTCG-SDT or a random access SDT RA-SDT procedure. Alternatively, or in combination thereof (depending on, for example, the RRC state of radio device 25), an indication for the selected repetition mode (which may be an indication to disable monitoring of the wake-up signal) can be sent via the Physical Uplink Control Channel (PUCCH), or via MAC CE, or as supplementary information.

[0167] As discussed above, Figure 9 The diagram illustrates corresponding steps of an exemplary embodiment of a method 90 for exchanging data, which can be implemented in the wireless device 25 of the UE 20. Figure 8 The method 80 for exchanging data shown is implemented by BS30.

[0168] like Figure 9 As shown, the method 90 for exchanging data includes step S90 of receiving from a wireless device 25 an indication of a repeating mode selected by the wireless device 25 from a plurality of repeating modes.

[0169] The method 90 for exchanging data further includes step S91, whereby the BS 30 sends a wake-up signal to the wireless device 25 by using a repeating mode selected by the wireless device 25 when the wireless device 25 is in a low-power operation mode. Of course, if the indication received from the wireless device 25 is an indication that a wake-up signal cannot be received, then the transmission of the wake-up signal is disabled for the wireless device 25.

[0170] In some examples, and such as Figure 9 As shown in the non-limiting example, BS 30 can use the received selected repetition pattern without any further verification. However, in other examples, BS 30 can evaluate other parameters to determine whether it can use the received selected repetition pattern to send a wake-up signal to the wireless device 25. For example, BS 30 can consider its load level and / or its power consumption in this evaluation. If the load level and / or its power consumption of BS 30 is low, the BS can apply the repetition pattern selected by the wireless device 25. However, if the load level and / or its power consumption of BS 30 is high, the BS can decide to ignore the instruction received from the wireless device 25. In this case, BS 30 can, for example, select another repetition pattern or disable the transmission of wake-up signals for the wireless device 25, and the BS sends a corresponding instruction to the wireless device 25.

Claims

1. A method (50) for exchanging data in a wireless communication system, the method being implemented by a wireless device (25) of the wireless communication system, wherein the wireless device comprises: a main radio, MR, unit (253) configured to exchange data with a Radio Access Network, RAN, of the wireless communication system; and a Low Power Wake-up Receiver, LP-WUR, (254) configured to detect a wake-up signal transmitted by the RAN, wherein the wireless device comprises at least two operating modes, including a normal operating mode and a low power operating mode, wherein: - in the normal operating mode, the MR unit is in an active state, - in the low power operating mode, the MR unit is in a low power state and the LP-WUR is configured to trigger a transition to the normal operating mode in response to detecting a wake-up signal transmitted by the RAN, wherein the RAN is adapted to transmit the wake-up signal by using a plurality of repetition patterns, the method comprising: - (S50) determining a repetition pattern of the plurality of repetition patterns used by the RAN for transmitting the wake-up signal, - (S51) estimating a reception level representative of an expected reception level of the wake-up signal transmitted by the RAN by the LP-WUR, - (S52) selecting an operating mode of the wireless device based on the determined repetition pattern and based on the estimated reception level.

2. The method (50) of claim 1, wherein the selection (S52) of the operating mode of the wireless device comprises: - in response to determining that the RAN uses a first repetition pattern: selecting the low power operating mode if the estimated reception level fulfills a first selection criterion, - in response to determining that the RAN uses a second repetition pattern different from the first repetition pattern: selecting the low power operating mode if the estimated reception level fulfills a second selection criterion different from the first selection criterion.

3. The method (50) of claim 2, wherein: - the first selection criterion is fulfilled if the estimated reception level is greater than a first threshold, and / or - the second selection criterion is fulfilled if the estimated reception level is greater than a second threshold different from the first threshold.

4. The method (50) of claim 3, wherein the first repetition pattern comprises fewer repetitions of the wake-up signal than the second repetition pattern, and the first threshold is greater than the second threshold.

5. The method (50) of any one of the preceding claims, wherein one of the plurality of repetition patterns comprises no repetition of the wake-up signal.

6. The method (50) of any one of the preceding claims, wherein the determination of the repetition pattern used by the RAN comprises receiving an indication from the RAN.

7. The method (50) of claim 6, wherein the indication is received in system information broadcast by the RAN.

8. A wireless device (25), the wireless device comprising at least one memory (251) and at least one processor (250), the at least one processor being configured to implement a method (50) according to any one of the preceding claims.

9. A user equipment, UE, (20), the UE comprising a wireless device according to claim 8.

10. A method (40) for exchanging data in a wireless communication system, the method being implemented by a base station, BS, of a radio access network, RAN, of the wireless communication system, wherein the BS is configured to exchange data with a wireless device, the wireless device comprising a main radio, MR, unit (253) and a low-power wake-up receiver, LP-WUR, (254), wherein the LP-WUR is configured to detect a wake-up signal transmitted by the BS and to trigger a transition of the MR unit from a low-power state to an active state in response to detecting the wake-up signal transmitted by the BS, wherein the method comprises: - (S40) selecting, among a plurality of repetition patterns, a repetition pattern for transmission of a wake-up signal, - (S41) transmitting the wake-up signal to the wireless device by using the selected repetition pattern.

11. The method (40) of claim 10, wherein the repetition pattern used is selected based on a load level of the BS and / or based on an energy consumption of the BS.

12. The method (40) of any one of claims 10 to 11, the method comprising transmitting (S42) an indication of the repetition pattern used to the wireless device.

13. The method (40) of claim 12, wherein the indication is comprised in system information broadcast by the BS.

14. The method (40) of any one of claims 12 to 13, wherein the indication is representative of a load level of the BS.

15. A base station, BS, (30), the BS comprising at least one memory (301) and at least one processor (300), the at least one processor being configured to implement a method (40) according to any one of claims 10 to 14.

16. A wireless communication system, the wireless communication system comprising at least one base station (30) according to claim 15 and at least one user equipment (20) according to claim 9.

17. A computer program product, the computer program product comprising instructions which, when executed by at least one processor, configure the at least one processor to implement a method (50) according to any one of claims 1 to 7 or a method (40) according to any one of claims 10 to 14.

18. A computer-readable storage medium, the computer-readable storage medium comprising instructions which, when executed by at least one processor, configure the at least one processor to implement a method according to any one of claims 1 to 7 or a method according to any one of claims 10 to 14.

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