Method, apparatus and computer program

Abstract

A terminal (user equipment, UE) detects a wake up signal (WUS) during a low power mode of the terminal. The terminal decodes signal information from the WUS (e.g. downlink control information (DCI)) and, in response to detection of the WUS, switches a main radio transceiver into an active mode. Using the main radio transceiver, the terminal performs a first control channel decoding operation if the decoded information from the WUS indicates a first address value, and the terminal performs a second, different, control channel decoding operations if the decoded information from the WUS indicates a second address value. The first and second control channel decoding operations may differ by: the duration spent on the decoding operation until the terminal returns to the low power mode, a search space set configuration, a periodicity of the decoding operation, or a number of slots to monitor for the decoding operation.

Description

FIELD

[0001] The present application relates to a method, apparatus, system and computer program and in particular but not exclusively to apparatus for employing a low power wake up signal. BACKGROUND

[0002] A communication system can be seen as a facility that enables communication sessions between two or more entities such as user terminals, base stations and / or other nodes by providing carriers between the various entities involved in the communications path. A communication system can be provided for example by means of a communication network and one or more compatible communication devices. The communication sessions may comprise, for example, communication of data for carrying communications such as voice, video, electronic mail (email), text message, multimedia and / or content data and so on. Non-limiting examples of services provided comprise two-way or multi-way calls, data communication or multimedia services and access to a data network system, such as the Internet.

[0003] In a wireless communication system at least a part of a communication session between at least two stations occurs over a wireless link. Examples of wireless systems comprise public land mobile networks (PLMN), satellite based communication systems and different wireless local networks, for example wireless local area networks (WLAN). Some wireless systems can be divided into cells, and are therefore often referred to as cellular systems.

[0004] A user can access the communication system by means of an appropriate communication device or terminal. A communication device of a user may be referred to as user equipment (UE) or user device. A communication device is provided with an appropriate signal receiving and transmitting apparatus for enabling communications, for example enabling access to a communication network or communications directly with other users. The communication device may access a carrier provided by a station, for example a base station of a cell, and transmit and / or receive communications on the carrier.

[0005] The communication system and associated devices typically operate in accordance with a given standard or specification which sets out what the various entities associated with the system are permitted to do and how that should be achieved. Communication protocols and / or parameters which shall be used for the connection are also typically defined. One example of a communications system is UTRAN (3G radio). Other examples of communication systems are the long-term evolution (LTE) of the Universal Mobile Telecommunications System (UMTS) radioaccess technology and so-called 5G or New Radio (NR) networks. NR is being standardized by the 3rd Generation Partnership Project (3GPP).

[0006] Energy efficiency, latency, reliability, and availability are critical in communication systems. In general, 5G terminal devices consume tens of milliwatts in radio resource control (RRC) idle / inactive state and hundreds of milliwatts in RRC connected state. Currently, UEs need to periodically wake up once per discontinuous reception (DRX) cycle, which dominates the power consumption in periods with no signaling or data traffic. If UEs are able to wake up only when they are addressed, e.g., by paging, power consumption could be dramatically reduced. This can be achieved by using a wake-up signal to trigger / wake-up the main radio and a separate receiver which has the ability to monitor wake-up signal with ultra-low power consumption. SUMMARY

[0007] According to a first aspect, there is provided a terminal device (UE) comprising: means for detecting a wake up signal during a low power mode operation of the terminal device; means for decoding signal information from the wake up signal; means for, in response to the detection of the wake up signal, switching a main radio transceiver of the terminal device into an active mode of operation; and means for performing, by the main radio transceiver, a first control channel decoding operation if the signal information indicates a first value, and a second control channel decoding operation different from the first control channel decoding operation if the signal information indicates a second value.

[0008] The signal information may be addressing information identifying one or more intended recipients of the wake up signal.

[0009] The first value may be a first address value for addressing a set of terminal devices, and the second value may be a second address value for addressing one or more terminal devices of the set of terminal devices, and wherein the one or more terminal devices includes the terminal device.

[0010] The set of terminal devices may comprise terminal devices that are in Radio Resource Control, RRC, connected state with a network device and that are in a low power mode operation.

[0011] The terminal device may further comprise means for receiving configuration information for configuring the first and second control channel decoding operations.

[0012] The first control channel decoding operation may differ from the second control channel decoding operation by at least one of: a minimum duration of the control channel decoding operation until the terminal device resumes the low power mode of operation; a search space set configuration; a periodicity of the control channel decoding operation while the main radio transceiver is in the active mode of operation; or a number of slots to monitor for the control channel decoding operation while the main radio transceiver is in the active mode of operation.

[0013] The terminal device may further comprise means for pausing the low power mode of operation if the signal information indicates the first value.

[0014] The low power mode of operation may be paused for a configured or predetermined duration.

[0015] The low power mode of operation may be paused for an undetermined duration, and wherein the terminal device may further comprise: means for receiving signaling information, the signaling information indicating a resumption of the low power mode of operation; and means for resuming the low power mode of operation in response to the reception of the signaling information.

[0016] The signaling information may be at least one of: Downlink Control Information, DCI; and medium access control control element, MAC-CE.

[0017] According to a second aspect there is provided a method comprising, by a terminal device: detecting a wake up signal during a low power mode operation of the terminal device; decoding signal information from the wake up signal; in response to the detection of the wake up signal, switching a main radio transceiver of the terminal device into an active mode of operation; and performing, by the main radio transceiver, a first control channel decoding operation if the signal information indicates a first value, and a second control channel decoding operation different from the first control channel decoding operation if the signal information indicates a second value.

[0018] The signal information may be addressing information identifying one or more intended recipients of the wake up signal.

[0019] The first value may be a first address value for addressing a set of terminal devices, and the second value may be a second address value for addressing one or more terminal devices of the set of terminal devices, and wherein the one or more terminal devices includes the terminal device.

[0020] The set of terminal devices may comprise terminal devices that are in Radio Resource Control, RRC, connected state with a network device and that are in a low power mode operation.

[0021] The method may further comprise receiving configuration information for configuring the first and second control channel decoding operations.

[0022] The first control channel decoding operation may differ from the second control channel decoding operation by at least one of: a minimum duration of the control channel decoding operation until the terminal device resumes the low power mode of operation; a search space set configuration; a periodicity of the control channel decoding operation while the main radio transceiver is in the active mode of operation; or a number of slots to monitor for the control channel decoding operation while the main radio transceiver is in the active mode of operation.

[0023] The method may further comprise pausing the low power mode of operation if the signal information indicates the first value.

[0024] The low power mode of operation may be paused for a configured or predetermined duration.

[0025] The low power mode of operation may be paused for an undetermined duration, and wherein the method may further comprise: receiving signaling information, the signaling information indicating a resumption of the low power mode of operation; and resuming the low power mode of operation in response to the reception of the signaling information.

[0026] The signaling information may be at least one of: Downlink Control Information, DCI; and medium access control control element, MAC-CE.

[0027] According to a third aspect there is provided a network device (NW) comprising: means for encoding signal information in a wake up signal; means for transmitting the wake up signal to a terminal device during a low power mode operation of the terminal device, the wake up signal triggering a switching of a main radio transceiver of the terminal device into an active mode of operation; means for assigning a first value to the signal information for performance by the terminal device of a first control channel decoding operation, or assigning a second value to the signal information for performance by the terminal device of a second control channel decoding operation different from the first control channel decoding operation.

[0028] The signal information may be addressing information identifying one or more intended recipients of the wake up signal.

[0029] The first value may be a first address value for addressing a set of terminal devices, and the second value may be a second address value for addressing one or more terminal devices of the set of terminal devices, and wherein the one or more terminal devices includes the terminal device.

[0030] The set of terminal devices may comprise terminal devices that are in Radio resource Control, RRC, connected state with the network device and that are in a low power mode operation.

[0031] The network device may further comprise: means for transmitting configuration information for configuring the first and second control channel decoding operations.

[0032] The first control channel decoding operation may differ from the second control channel decoding operation by at least one of: a minimum duration of the control channel decoding operation until the terminal device resumes the low power mode of operation; a search space set configuration; a periodicity of the control channel decoding operation while the main radio transceiver is in the active mode of operation; or a number of slots to monitor for the control channel decoding operation while the main radio transceiver is in the active mode of operation.

[0033] The network device may further comprise means for assigning the first value to the signal information for pausing the low power mode of operation of the terminal device.

[0034] The low power mode of operation may be paused for a configured or predetermined duration.

[0035] The low power mode of operation may be paused for an undetermined duration, and wherein the network device may further comprise means for transmitting signaling information, the signaling information indicating a resumption of the low power mode of operation by the terminal device.

[0036] The signaling information may be at least one of: Downlink Control Information, DCI; and medium access control control element, MAC-CE.

[0037] According to a fourth aspect there is provided a method by a network device comprising: encoding signal information in a wake up signal; transmitting the wake up signal to a terminal device during a low power mode operation of the terminal device, the wake up signal triggering a switching of a main radio transceiver of the terminal device into an active mode of operation; and assigning a first value to the signal information for performance by the terminal device of a first control channel decoding operation, or assigning a second value to the signal information for performance by the terminal device of a second control channel decoding operation different from the first control channel decoding operation.

[0038] The signal information may be addressing information identifying one or more intended recipients of the wake up signal.

[0039] The first value may be a first address value for addressing a set of terminal devices, and the second value may be a second address value for addressing one or more terminal devices of the set of terminal devices, and wherein the one or more terminal devices includes the terminal device.

[0040] The set of terminal devices may comprise terminal devices that are in Radio resource Control, RRC, connected state with the network device and that are in a low power mode operation.

[0041] The method may further comprise transmitting configuration information for configuring the first and second control channel decoding operations.

[0042] The first control channel decoding operation may differ from the second control channel decoding operation by at least one of: a minimum duration of the control channel decoding operation till the terminal device resumes the low power mode of operation; a search space set configuration; a periodicity of the control channel decoding operation while the main radio transceiver is in the active mode of operation; or a number of slots to monitor for the control channel decoding operation while the main radio transceiver is in the active mode of operation.

[0043] The method may further comprise assigning the first value to the signal information for pausing the low power mode of operation of the terminal device.

[0044] The low power mode of operation may be paused for a configured or predetermined duration.

[0045] The low power mode of operation may be paused for an undetermined duration, and wherein the method may further comprise transmitting signaling information, the signaling information indicating a resumption of the low power mode of operation by the terminal device.

[0046] The signaling information may be at least one of: Downlink Control Information, DCI; and medium access control control element, MAC-CE.

[0047] According to a fifth aspect, there is provided an apparatus, a terminal device (UE), comprising at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to perform: detecting a wake up signal during a low power mode operation of the terminal device; decoding signal information from the wake up signal; in response to the detection of the wake up signal, switching a main radio transceiver of the terminal device into an active mode of operation; and performing, by the main radio transceiver, a first control channel decoding operation if the signal information indicates a first value, and a second control channel decoding operation different from the first control channel decoding operation if the signal information indicates a second value.

[0048] The signal information may be addressing information identifying one or more intended recipients of the wake up signal.

[0049] The first value may be a first address value for addressing a set of terminal devices, and the second value may be a second address value for addressing one or more terminal devices of the set of terminal devices, and wherein the one or more terminal devices includes the terminal device.

[0050] The set of terminal devices may comprise terminal devices that are in Radio Resource Control, RRC, connected state with a network device and that are in a low power mode operation.

[0051] The terminal device may further comprise means for receiving configuration information for configuring the first and second control channel decoding operations.

[0052] The first control channel decoding operation may differ from the second control channel decoding operation by at least one of: a minimum duration of the control channel decoding operation till the terminal device resumes the low power mode of operation; a search space set configuration; a periodicity of the control channel decoding operation while the main radio transceiver is in the active mode of operation; or a number of slots to monitor for the control channel decoding operation while the main radio transceiver is in the active mode of operation.

[0053] The apparatus may further be caused to perform pausing the low power mode of operation if the signal information indicates the first value.

[0054] The low power mode of operation may be paused for a configured or predetermined duration.

[0055] The low power mode of operation may be paused for an undetermined duration, and wherein the apparatus may be further caused to perform: receiving signaling information, the signaling information indicating a resumption of the low power mode of operation; and resuming the low power mode of operation in response to the reception of the signaling information.

[0056] The signaling information may be at least one of: Downlink Control Information, DCI; and medium access control control element, MAC-CE.

[0057] According to a sixth aspect, there is provided an apparatus, a network device, comprising at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to perform: encoding signal information in a wake up signal; transmitting the wake up signal to a terminal device during a low power mode operation of the terminal device, the wake up signal triggering a switching of a main radio transceiver of the terminal device into an active mode of operation; and assigning a first value to the signal information for performance by the terminal device of a first control channel decoding operation, or assigning a second value to the signal information for performance by the terminal device of a second control channel decoding operation different from the first control channel decoding operation.

[0058] The signal information may be addressing information identifying one or more intended recipients of the wake up signal.

[0059] The first value may be a first address value for addressing a set of terminal devices, and the second value may be a second address value for addressing one or more terminal devices of the set of terminal devices, and wherein the one or more terminal devices includes the terminal device.

[0060] The set of terminal devices may comprise terminal devices that are in Radio resource Control, RRC, connected state with the network device and that are in a low power mode operation.

[0061] The apparatus may be further caused to perform transmitting configuration information for configuring the first and second control channel decoding operations.

[0062] The first control channel decoding operation may differ from the second control channel decoding operation by at least one of: a minimum duration of the control channel decoding operation till the terminal device resumes the low power mode of operation; a search space set configuration; a periodicity of the control channel decoding operation while the main radio transceiver is in the active mode of operation; or a number of slots to monitor for the control channel decoding operation while the main radio transceiver is in the active mode of operation.

[0063] The apparatus may be further caused to perform assigning the first value to the signal information for pausing the low power mode of operation of the terminal device.

[0064] The low power mode of operation may be paused for a configured or predetermined duration.

[0065] The low power mode of operation may be paused for an undetermined duration, and wherein the apparatus may be further caused to perform transmitting signaling information, the signaling informaiton indicating a resumption of the low power mode of operation by the terminal device.

[0066] The signaling information may be at least one of: Downlink Control Information, DCI; and medium access control control element, MAC-CE.

[0067] According to a seventh aspect, there is provided an apparatus, a terminal device (UE), comprising means for performing: detecting a wake up signal during a low power mode operation of the terminal device; decoding signal information from the wake up signal; in response to the detection of the wake up signal, switching a main radio transceiver of the terminal device into an active mode of operation; and performing, by the main radio transceiver, a first control channel decoding operation if the signal information indicates a first value, and a second control channel decoding operation different from the first control channel decoding operation if the signal information indicates a second value.

[0068] According to an eighth aspect, there is provided an apparatus, network device (NW), comprising means for performing: encoding signal information in a wake up signal; transmitting the wake up signal to a terminal device during a low power mode operation of the terminal device, the wake up signal triggering a switching of a main radio transceiver of the terminal device into an active mode of operation; assigning a first value to the signal information for performance by the terminal device of a first control channel decoding operation, or assigning a second value to the signal information for performance by the terminal device of a second control channel decoding operation different from the first control channel decoding operation.

[0069] According to a ninth aspect, there is provided a computer readable medium comprising instructions which, when executed by an apparatus, a terminal device (UE), cause the apparatus to perform at least the following: detecting a wake up signal during a low power mode operation of the terminal device; decoding signal information from the wake up signal; in response to the detection of the wake up signal, switching a main radio transceiver of the terminal device into an active mode of operation; and performing, by the main radio transceiver, a first control channel decoding operation if the signal information indicates a first value, and a second control channel decoding operation different from the first control channel decoding operation if the signal information indicates a second value.

[0070] According to a tenth aspect, there is provided a computer readable medium comprising instructions which, when executed by an apparatus, a network device (NW), cause the apparatus to perform at least the following: encoding signal information in a wake up signal; transmitting the wake up signal to a terminal device during a low power mode operation of the terminal device, the wake up signal triggering a switching of a main radio transceiver of the terminal device into an active mode of operation; assigning a first value to the signal information for performance by the terminal device of a first control channel decoding operation, or assigning a second value to the signal information for performance by the terminal device of a second control channel decoding operation different from the first control channel decoding operation.

[0071] According to an aspect, there is provided a non-transitory computer readable medium comprising program instructions that, when executed by an apparatus, cause the apparatus to perform at least the method according to any of the preceding aspects.

[0072] In the above, many different embodiments have been described. It should be appreciated that further embodiments may be provided by the combination of any two or more of the embodiments described above. DESCRIPTION OF FIGURES

[0073] Embodiments will now be described, by way of example only, with reference to the accompanying Figures in which:

[0074] Fig. 1 shows a representation of a network system according to some example embodiments;

[0075] Fig. 2 shows a representation of a control apparatus according to some example embodiments;

[0076] Fig. 3 shows a representation of an apparatus according to some example embodiments;

[0077] Fig. 4 shows a representation of the apparatus as shown in Fig. 3 implementing a low power wake-up receiver and main radio receiver configuration according to some example embodiments;

[0078] Figs. 5 to 7 show example wake-up-signal related activation of a control channel decoder according to some embodiments; and

[0079] Fig. 8 shows a summary operation of the application of the wake-up-signal according to some embodiments. DETAILED DESCRIPTION

[0080] The following relates to low-power wake-up signal configuration over a 5G or NR air interface. In the following certain embodiments are explained with reference to mobile communication devices capable of communication via a wireless cellular system and mobile communication systems serving such mobile communication devices. Before explaining in detail the exemplifying embodiments, certain general principles of a wireless communication system, access systems thereof, and mobile communication devices are briefly explained with reference to Figs. 1,2 and 3 to assist in understanding the technology underlying the described examples. It is understood that the following description is not limited to 5G systems and may be expanded to later developed systems (e.g., 6G and beyond).

[0081] Fig. 1 shows a schematic representation of a 5G system (5GS). The 5GS may be comprised by a terminal device or user equipment (UE), a 5G radio access network (5GRAN) or next generation radio access network (NG-RAN), a 5G core network (5GC), one or more application function (AF) and one or more data networks (DN).

[0082] The 5GC may comprise the following entities: Network Slice Selection Function (NSSF); Network Exposure Function; Network Repository Function (NRF); Policy Control Function (PCF); Unified Data Management (UDM); Application Function (AF); Authentication Server Function (AUSF); an Access and Mobility Management Function (AMF); and Session Management Function (SMF). Figure 1 also shows the various interfaces (N1, N2 etc.) that may be implemented between the various elements of the system.

[0083] The 5G-RAN may comprise one or more gNodeB (gNB) or one or more gNodeB (GNB) distributed unit functions connected to one or more gNodeB (gNB) centralized unit functions.

[0084] The 5G-RAN may be configured to support a low-power operation of the terminal device while the terminal device is operating in a RRC connected mode. This support involve transmitting suitable wake-up signals to a terminal device within a cell, as discussed in further detail herein.

[0085] Fig. 2 illustrates an example of a control apparatus 200 for controlling a function of the 5GRAN or the 5GC as illustrated on Fig. 1. The control apparatus may comprise at least one random access memory (RAM) 211 a, at least on read only memory (ROM) 211b, at least one processor 212, 213 and an input / output interface 214. The at least one processor 212, 213 may be coupled to the RAM 211a and the ROM 211b. The at least one processor 212, 213 may be configured to execute an appropriate software code 215. The software code 215 may for example allow to perform one or more steps to perform one or more of the present aspects. The software code 215 may be stored in the ROM 211b. The control apparatus 200 may be interconnected with another control apparatus 200 controlling another function of the 5GRAN or the 5GC. In some embodiments, each function of the 5GRAN or the 5GC comprises a control apparatus 200. In alternative embodiments, two or more functions of the 5GRAN or the 5GC may share a control apparatus.

[0086] Fig. 3 illustrates an example of a terminal device 300, such as the terminal device illustrated on Fig. 1. The terminal device 300 may be provided by any device capable of sending and receiving radio signals. Non-limiting examples comprise a user equipment, a mobile station (MS) or mobile device such as a mobile phone or what is known as a ’smart phone’, a computer provided with a wireless interface card or other wireless interface facility (e.g., USB dongle), a personal data assistant (PDA) or a tablet provided with wireless communication capabilities, a machine-type communications (MTC) device, an Internet of things (loT) type communication device or any combinations of these or the like. The terminal device 300 may provide, for example, communication of data for carrying communications. The communications may be one or more of voice, electronic mail (email), text message, multimedia, data, machine data and so on.

[0087] The terminal device 300 may receive signals over an air or radio interface 307 via appropriate apparatus for receiving and may transmit signals via appropriate apparatus for transmitting radio signals. In Fig. 3 transceiver apparatus is designated schematically by block 306. The transceiver apparatus 306 may be provided for example by means of a radio part and associated antenna arrangement. The antenna arrangement may be arranged internally or externally to the mobile device.

[0088] The terminal device 300 may be provided with at least one processor 301, at least one memory ROM 302a, at least one RAM 302b and other possible components 303 for use in software and hardware aided execution of tasks it is designed to perform, including control of access to and communications with access systems and other communication devices. The at least one processor 301 is coupled to the RAM 302b and the ROM 302a. The at least one processor 301 may be configured to execute an appropriate software code 308. The software code 308 may for example allow to perform one or more of the present aspects. The software code 308 may be stored in the ROM 302a.

[0089] The processor, storage and other relevant control apparatus can be provided on an appropriate circuit board and / or in chipsets. This feature is denoted by reference 304. The device may optionally have a user interface such as key pad 305, touch sensitive screen or pad, combinations thereof or the like. Optionally one or more of a display, a speaker and a microphone may be provided depending on the type of the device.

[0090] The low power wake-up signal (LP-WUS) mode of operation is a type of power saving mechanism introduced in NR release 16. LP-WUS mode of operation attempts to reduce power consumption by letting a terminal device to continue to sleep, even when the terminal device is operating in an RRC connected state or during a discontinuous reception (DRX) OnDuration period when there is no data for the terminal device. The network device, the gNB, is configured to notify the terminal device using a 'Wake Up' signal when there is data for the terminal device. The terminal device, then, is configured to wake up and receive data during the configured OnDuration time period. Although the following examples are described with respect to the terminal device being operated in the CONNECTED mode, it can also be employed in other modes such as IDLE / INACTIVE modes.

[0091] Additionally, the terminal device can comprise a main radio and a separate low-power wake-up receiver (which can also be referred to as an ultra-low power wake-up receiver or more generally WUS receiver). This configuration is shown in Fig.4 where the terminal device 300 is shown comprising separate ultra-low power wake-up receiver 421 and main radio 431. As illustrated in Fig.4, the network device may trigger the terminal device to wake-up exactly when needed in an event-driven manner by transmitting a special WUS to the terminal device, which is monitored by a dedicated low-power WUS receiver at the terminal device. When the terminal device receives the WUS, the WUS receiver may trigger the wake-up of the ordinary NR transceiver and communication may start. Thus, the ultra-low power receiver may wake-up the main radio (NR transceiver) of the terminal device as shown on the right side 403 of Fig.4. Otherwise, the main radio of the terminal device is off, or kept in a deep sleep mode as shown on the left side 401 of Fig.4.

[0092] The intention behind employing LP-WUS mode of operation and separate radios is therefore that the main radio of the terminal device can be in a sleep mode (or even powered off) for power saving and be activated only upon the reception of the wake-up signal from the network device.

[0093] The WUS receiver can, in some embodiments, be operated in an always ‘on’ manner with very low power consumption. It is expected that the WUS receiver consumes significantly less power compared to the main radio (NR transceiver). This can be achieved by designing a simple (WUS) signal and employing a low complexity encoding and modulation scheme for the WUS. The low complexity and simple WUS permits the WUS receiver to monitor the WUS using dedicated hardware configured to only receive the WUS.

[0094] An example WUS receiver can for example (and described in further detail in TS 38.869) comprises a matching network coupled to an antenna configured to receive the WUS. Following the matching network, a RF band pass filter and RF Low noise amplifier is then configured to pass the RF signal to a RF envelope detector. The output of the RF envelope detector is passed to a base band amplifier and base band low pass filter which outputs an analogue base band signal. The analogue base band signal can be converted to the digital domain using a 1 -bit or multi-bit ADC and the digital signal output to a digital baseband processor. The output of the WUS receiver is therefore a low bit rate signal or symbol.

[0095] The WUS as currently discussed are suitable in low traffic load scenarios as they are configured to address one terminal device at a time. However, congestion can occur in high traffic load scenarios where there are many terminal devices in a cell with frequent data transmissions. This is particularly the situation where the terminal devices are in the CONNECTED mode rather than an IDLE / INACTIVE mode where the wake-up signal triggering can be expected to be infrequent.

[0096] Although the WUS can be transmitted continuously in order to enable sufficient capacity to address more than one or all of the terminal devices in the cell, this results in a significant increase in the network terminal power usage even in circumstances where there are possible breaks in the transmissions to save power.

[0097] The concept, which is discussed in further detail with respect to the following embodiments, relates to the design and implementation of a suitable WUS configuration to overcome the network capacity or congestion. Additionally, the following embodiments employ the currently implemented WUS time period to attempt to optimise the transmission power used by the network terminal and further employ a known terminal device WUS receiver design and thus overcome the need to employ a more complex receiver arrangement, for example multiple frequency domain multiplexed WUS receivers.

[0098] The embodiments as described in further detail herein are to employ a WUS which has the capacity to initiate the one or more terminal devices to switch the main radio into an active mode of operation for a one off control channel (such as physical downlink control channel, PDCCH) decoding. The switching of the main radio into an active mode allows the system to schedule I wake-up multiple terminal devices at the time. Alternatively the WUS can be designed such that the terminal devices could be configured when detecting a specific or defined WUS value that the switching of the main radio is to be employ a periodic “regular” PDCCH decoding. In such a manner that the terminal device is not required to be addressed every time.

[0099] In other words, the terminal device comprises means for detecting a wake up signal during a low power mode operation of the terminal device.

[0100] Furthermore, the terminal device comprises means for decoding signal information from the wake up signal.

[0101] In response to the detection of the wake up signal, the terminal device can furthermore comprise means for switching a main radio transceiver of the terminal device into an active mode of operation. The switching of the main radio transceiver can also be considered in some embodiments to be a waking up of the main radio transceiver.

[0102] The terminal device furthermore comprises means for performing, by the main radio transceiver, a first control channel decoding operation if the signal information indicates a first value, and a second control channel decoding operation different from the first control channel decoding operation if the signal information indicates a second value.

[0103] The signal information can in some embodiment, be addressing information identifying one or more intended recipients of the wake up signal. The addressing information can be configured to be detected at the terminal device as identifying the terminal device.

[0104] Furthermore, in some embodiments the first value can be a first address value for addressing a set of terminal devices, and the second value is a second address value for addressing one or more terminal devices of the set of terminal devices, and wherein the one or more terminal devices includes the terminal device. In such a manner the WUS values can address a selection of the set of terminal devices in the cell. In other words, the addressing information can uniquely identify the terminal device or a restricted group of terminal devices (including the terminal device) as the intended and addressed recipient of the wake up signal, or identify many terminal devices (including the terminal device) or all the terminal devices as the intended and addressed recipient of the wake up signal.

[0105] Additionally in some embodiments the terminal devices are, as discussed above in a Radio Resource Control, RRC, connected state with a network device and are in a low power mode operation.

[0106] In some embodiments the terminal device comprises means for receiving configuration information for configuring the first and second control channel decoding operations. This configuration information can for example be received by a RRC configuration means or any other suitable means.

[0107] The first control channel decoding operation, in some embodiments, differs from the second control channel decoding operation by: a minimum duration of the control channel decoding operation till the terminal device resumes the low power mode of operation.

[0108] It is appreciated that although a duration of the control channel decoding operation can be configured or controlled based on signal information, for example setting a decoding operation timer within which the decoding operation is implemented, that such a configuration can be used to set a minimum duration but that the duration can be extended, when for example new incoming traffic is expected for the terminal device .

[0109] In other words, controlling the main radio to be kept active very much depends on whether the terminal device is scheduled with some PDSCH / PUSCH traffic or not. Indeed, where there is traffic scheduled for this terminal device, then an extra 'inactivity timer' is likely to be started to prolong the main radio active mode as further traffic for that UE may be expected (in a manner similar to Discontinuous Reception - DRX). However, if there is no traffic for the terminal device, then the main radio is only active during this minimal duration; if there is traffic scheduled for the terminal device, then the main radio may be active beyond this minimum duration.

[0110] In some embodiments the first control channel decoding operation, in some embodiments, differs from the second control channel decoding operation by a search space set configuration. In other words the signal information values can be configured to identity or address specific search space set configurations. The search space set configurations can, for example, identify the control channel monitoring occasions to be monitored in the time domain.

[0111] The first control channel decoding operation, in some embodiments, differs from the second control channel decoding operation by a periodicity of the control channel decoding operation while the main radio transceiver is in the active mode of operation. For example, the signal information values can identify a monitoring frequency for decoding the control channel.

[0112] Furthermore, the first control channel decoding operation, in some embodiments, differs from the second control channel decoding operation by a number of slots to monitor for the control channel decoding operation while the main radio transceiver is in the active mode of operation, for example, a number of contiguous slots to monitor.

[0113] The associating a different search space set (SSS) configuration to the first and second control channel decoding operations, can in some embodiments define a CORESET ID associated with the SSS, where to find the CORESET within a slot (starting symbol of the CORESET), a number of consecutive slots to monitor, and a periodicity of those monitored slots.

[0114] In such a manner the decoding operations can define such elements as a (minimum) duration of the control channel decoding operation , the search space to use to decode the control channel; the periodicity of the control channel decoding operation; or a number of slots or control channel instances to monitor (or control channel decoding instances to perform). Thus, based on the detected value of the signal information, the decoding operation can be configured or controlled to be as long, as often and for as many times as required. This is advantageous as an embodiment as rather than individually signalling the terminal device each time data is to be transmitted, the WUS can effectively schedule more terminal devices to wake up when a longer and / or more frequent control channel decoding operation is expected to be required.

[0115] The terminal device can furthermore, in some embodiments, further comprise means for pausing the low power mode of operation if the signal information indicates the first value. Thus, during high traffic periods, where the WUS would be triggering the main receiver very often and thus potentially causing congestion for other terminal devices in the cell, the low power mode signalling can be paused.

[0116] The low power mode of operation can be paused, in some embodiments, for a configured or pre-determined duration. Otherwise in some embodiments the pause can be for an undetermined duration, in which case the terminal device can further comprise means for receiving a signal to resume the low power mode of operation. This signal to resume the low power mode of operation can be sent via Downlink Control Information (DCI) or Medium Access Control - control element (MAC-CE) signaling.

[0117] From the viewpoint of the network device, for example a gNB or other suitable RAN controller, there can in some embodiments be a network device comprising means for encoding signal information in a wake up signal and means for transmitting the wake up signal to a terminal device during a low power mode operation of the terminal device, the wake up signal triggering a switching of a main radio transceiver of the terminal device into an active mode of operation (or triggering a waking up of a main radio transceiver of the terminal device).

[0118] Additionally, the network device comprises means for assigning a first value to the signal information for performance by the terminal device of a first control channel decoding operation, or assigning a second value to the signal information for performance by the terminal device of a second control channel decoding operation different from the first control channel decoding operation. Thus, as discussed above, the network device can control the decoding operation of a control channel of the wake-up operation at the terminal device by assigning values to the signal information, where the different values control different modes of operation for the control channel decoding.

[0119] As described above the signal information may be addressing information identifying one or more intended recipients of the wake-up-signal. Therefore, the signal information values identify one or more of the terminal devices.

[0120] The network can furthermore comprise means for transmitting configuration information for configuring the first and second control channel decoding operations.

[0121] To summarise the operations of the method with respect to the terminal device, there are the steps of: (a) detecting a wake up signal during a low power mode operation of the terminal device; (b) decoding signal information from the wake up signal; (c) in response to the detection of the wake up signal, switching a main radio transceiver of the terminal device into an active mode of operation; and (d) performing, by the main radio transceiver, a first control channel decoding operation if the signal information indicates a first value, and a second control channel decoding operation different from the first control channel decoding operation if the signal information indicates a second value.

[0122] Furthermore, a summary of the operations of the method with respect to the network device there can be implemented the following steps: (a) encoding signal information in a wake up signal; (b) transmitting the wake up signal to a terminal device during a low power mode operation of the terminal device, the wake up signal triggering a switching of a main radio transceiver of the terminal device into an active mode of operation; and (c) assigning a first value to the signal information for performance by the terminal device of a first control channel decoding operation, or assigning a second value to the signal information for performance by the terminal device of a second control channel decoding operation different from the first control channel decoding operation.

[0123] Examples which show data transmission improvements when employing embodiments can be seen with respect to Figures 5 to 8.

[0124] Fig. 5, for example, shows a conventional signalling scenario, where the wake up signal 501 is configured to wake-up a single terminal device, and the active time 503 shows low data amount per user 505 with the wake-up-signal mode implemented. This can lead to transmission buffers filling up as discussed above.

[0125] With respect to Fig. 6 is shown an example where a signalling scenario implements embodiments as discussed above. In this example a single terminal device wake-up-signal 501 is shown (where the signal information has a value addressing a single terminal device) and which results in a low data amount 505 as shown with respect to Fig. 5. Additionally, as shown in Fig 6 is a multi-terminal device wake-up-signal 601, which comprises a value which is detected by multiple terminal devices, and results in a one-off PDCCH decoding instructions for multiple users 605,which results in a significant increase in data transmission during the active time 503.

[0126] Fig.7 builds on the example shown in Fig. 6 where the multi-terminal device wake-up-signal 601 comprises a value which is detected by multiple terminal devices, and results in a periodic PDCCH decoding instruction for multiple users 701. The periodic PDCCH decoding instruction can control the frequency of the decoding, the number of instances of decoding, or more generally when the decoding is to be implemented 703.

[0127] With respect to Fig. 8 is shown a flow diagram showing a high level or overview implementation of some embodiments.

[0128] Thus, as shown by 801, the terminal device or UE is configured to connect to the network device or base station (BS).

[0129] Then the terminal device or UE, as shown by 803, is configured to report the WUS capability to the network device. In other words, the terminal device reports to the network device whether it is able to implement and process WUS operations.

[0130] Where the terminal device has no capability to implement WUS operations, then a regular operation based on PDCCH decoding is implemented, as shown by 807.

[0131] Where the terminal device has the ability or capability to implement WUS operations, then there is a determination of whether the terminal device has been configured with the WUS and PDCCH decoding periodicity as shown by 805. More generally, 805, can be an operation of determining whether the terminal device has been configured to detect different signal information values from the WUS, and implement different control channel decoding operations based on the different values.

[0132] Where the terminal device has not been configured with the WUS and PDCCH decoding periodicity then the terminal device can be configured to implement a regular operation based on PDCCH decoding, as shown by 807.

[0133] Where the terminal device has been configured with the WUS and PDCCH decoding periodicity, then the terminal device can be configured to monitor the WUS as shown by 809.

[0134] As some point, as shown by 811, a wake-up-signal is received which in this example comprises a signal information value which indicates a specific periodic control channel decoding operation.

[0135] Then, there is a determination, as shown by 813, of whether a PDCCH has been found indicating data reception via physical downlink shared channel (PDSCH).

[0136] Where there is no determination of a PDCCH indicating PDSCH reception, then the terminal device can be configured to switch back to monitoring the WUS (as shown by 809).

[0137] Where there is a determination of a PDCCH indicating PDSCH reception, then the terminal device can be configured to perform PDSCH decoding as shown by 815.

[0138] Following the PDSCH decoding there can be determination of whether there is a further PDCCH found or whether a retransmission pending as shown by 817.

[0139] Where there is a determination of a further PDCCH found or whether a retransmission pending, then the terminal device can be configured to switch back to perform PDSCH decoding (as shown by 815).

[0140] Where there is no determination of a further PDCCH found or whether a retransmission pending, then the terminal device can be configured to switch back to monitoring the WUS (as shown by 809).

[0141] The following discusses an implementation of example embodiments such as provided above in a high traffic load scenario:

[0142] Firstly a CONNECTED mode terminal device (UE) is configured (by a network device or NW) with LP-WUS monitoring so that LP-WUS can be used to trigger the terminal device to start onDurationTimer (resulting PDCCH monitoring) and conditions based on which terminal device can fallback to LP-WUS monitoring, e.g. by means of an InactivityTimer.

[0143] In such an example the LP-WUS configuration furthermore comprises an information field or a sequence that can be used to deactivate the LP-WUS monitoring configuration(s).

[0144] Additionally in some implementations there can be multiple different LP-WUS monitoring configurations, of which one or more can be active

[0145] Secondly the terminal device (for example UE) starts to apply LP-WUS monitoring configuration, and based on a condition (e.g. due to data inactivity timer) stops MR based monitoring (of PDCCH) and starts to apply LP-WUS monitoring.

[0146] Thirdly the network experiences an increase in traffic load, and to limit the LP-WUS overhead, decides to disable the LP-WUS configuration for a terminal device or for more than one terminal device.

[0147] Fourthly after terminal device fallback to LP-WUS monitoring (e.g. due to data inactivity), the terminal device detects a LP-WUS indicating UE to deactivate the LP-WUS monitoring configuration

[0148] Thus the terminal device stops the LP-WUS monitoring and resumes normal operation MR monitoring.

[0149] The terminal device considers the indicated LP-WUS monitoring configuration to be deactivated and does not resume the LP-WUS monitoring

[0150] For example, any associated triggers to cause the terminal device to fallback to LP-WUS monitoring are considered invalid and not applied

[0151] Fifthly the traffic load is reduced, and network decided to re-enable LP-WUS based operation for a terminal device or more than one terminal device. The Network transmits signaling information, for example via DCI, to the terminal device(s) to activate the LP-WUS monitoring configuration

[0152] The terminal devices detect in the signaling information, for example the DCI, that (selected) LP-WYS monitoring configuration is activated, and activates and applies the LP-WUS configuration.

[0153] Although the above examples show the main radio and a separate low-power wake-up receiver (which can also be referred to as an ultra-low power wake-up receiver or more generally WUS receiver) as separate parts or devices, it is understood that in some embodiments the main radio is configured to implement the functionality of the low-power wake-up receiver according to the above embodiments. For example the main radio is configured to switch to a low-power mode of operation implementing the functions of the low-power wake-up receiver described above.

[0154] It should be understood that the apparatuses may comprise or be coupled to other units or modules etc., such as radio parts or radio heads, used in or for transmission and / or reception. Although the apparatuses have been described as one entity, different modules and memory may be implemented in one or more physical or logical entities.

[0155] It is noted that whilst some embodiments have been described in relation to 5G networks, similar principles can be applied in relation to other networks and communication systems. Therefore, although certain embodiments were described above by way of example with reference to certain example architectures for wireless networks, technologies and standards, embodiments may be applied to any other suitable forms of communication systems than those illustrated and described herein.

[0156] It is also noted herein that while the above describes example embodiments, there are several variations and modifications which may be made to the disclosed solution without departing from the scope of the present invention.

[0157] As used herein, “at least one of the following: ” and “at least one of ” and similar wording, where the list of two or more elements are joined by “and” or “or”, mean at least any one of the elements, or at least any two or more of the elements, or at least all the elements.

[0158] In general, the various embodiments may be implemented in hardware or special purpose circuitry, software, logic or any combination thereof. Some aspects of the disclosure may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device, although the disclosure is not limited thereto. While various aspects of the disclosure may be illustrated and described as block diagrams, flow charts, or using some other pictorial representation, it is well understood that these blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

[0159] As used in this application, the term “circuitry” may refer to one or more or all of the following: (a) hardware-only circuit implementations (such as implementations in only analog and / or digital circuitry) and (b) combinations of hardware circuits and software, such as (as applicable): (c) a combination of analog and / or digital hardware circuit(s) with software / firmware and (i) any portions of hardware processor(s) with software (including digital signal processor(s)), software, and memory(ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions); and (ii) hardware circuit(s) and or processor(s), such as a microprocessor(s) or a portion of a microprocessor(s), that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation.”

[0160] This definition of circuitry applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and / or firmware. The term circuitry also covers, for example and if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in server, a cellular network device, or other computing or network device.

[0161] The embodiments of this disclosure may be implemented by computer software executable by a data processor of the mobile device, such as in the processor entity, or by hardware, or by a combination of software and hardware. Computer software or program, also called program product, including software routines, applets and / or macros, may be stored in any apparatus-readable data storage medium and they comprise program instructions to perform particular tasks. A computer program product may comprise one or more computer-executable components which, when the program is run, are configured to carry out embodiments. The one or more computer-executable components may be at least one software code or portions of it.

[0162] Further in this regard it should be noted that any blocks of the logic flow as in the Figures may represent program steps, or interconnected logic circuits, blocks and functions, or a combination of program steps and logic circuits, blocks and functions. The software may be stored on such physical media as memory chips, or memory blocks implemented within the processor, magnetic media such as hard disk or floppy disks, and optical media such as for example DVD and the data variants thereof, CD. The physical media is a non-transitory media.

[0163] The term “non-transitory,” as used herein, is a limitation of the medium itself (i.e., tangible, not a signal ) as opposed to a limitation on data storage persistency (e.g., RAM vs. ROM).

[0164] The memory may be of any type suitable to the local technical environment and may be implemented using any suitable data storage technology, such as semiconductor based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory. The data processors may be of any type suitable to the local technical environment, and may comprise one or more of general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs), application specific integrated circuits (ASIC), FPGA, gate level circuits and processors based on multi core processor architecture, as non-limiting examples.

[0165] Embodiments of the disclosure may be practiced in various components such as integrated circuit modules. The design of integrated circuits is by and large a highly automated process. Complex and powerful software tools are available for converting a logic level design into a semiconductor circuit design ready to be etched and formed on a semiconductor substrate.

[0166] The scope of protection sought for various embodiments of the disclosure is set out by the independent claims. The embodiments and features, if any, described in this specification that do not fall under the scope of the independent claims are to be interpreted as examples useful for understanding various embodiments of the disclosure.

[0167] The foregoing description has provided by way of non-limiting examples a full and informative description of the exemplary embodiment of this disclosure. However, various modifications and adaptations may become apparent to those skilled in the relevant arts in view of the foregoing description, when read in conjunction with the accompanying drawings and the appended claims. However, all such and similar modifications of the teachings of this disclosure will still fall within the scope of this invention as defined in the appended claims. Indeed, there is a further embodiment comprising a combination of one or more embodiments with any of the other embodiments previously discussed.

Claims

1. A terminal device (UE) comprising:means for detecting a wake up signal during a low power mode operation of the terminal device;means for decoding signal information from the wake up signal;means for, in response to the detection of the wake up signal, switching a main radio transceiver of the terminal device into an active mode of operation ; andmeans for performing, by the main radio transceiver, a first control channel decoding operation if the signal information indicates a first value, and a second control channel decoding operation different from the first control channel decoding operation if the signal information indicates a second value.

2. The terminal device of claim 1, wherein the signal information is addressing information identifying one or more intended recipients of the wake up signal.

3. The terminal device of claim 2, wherein the first value is a first address value for addressing a set of terminal devices, and the second value is a second address value for addressing one or more terminal devices of the set of terminal devices, and wherein the one or more terminal devices includes the terminal device.

4. The terminal device of claim 3, wherein the set of terminal devices comprises terminal devices that are in Radio Resource Control, RRC, connected state with a network device and that are in a low power mode operation.

5. The terminal device of any of claims 1 to 4 further comprising means for receiving configuration information for configuring the first and second control channel decoding operations.

6. The terminal device of any of claims 1 to 5, wherein the first control channel decoding operation differs from the second control channel decoding operation by at least one of:a minimum duration of the control channel decoding operation till the terminal device resumes the low power mode of operation;a search space set configuration;a periodicity of the control channel decoding operation while the main radio transceiver is in the active mode of operation; ora number of slots to monitor for the control channel decoding operation while the main radio transceiver is in the active mode of operation.

7. The terminal device of any of claims 1 to 6, further comprising means for pausing the low power mode of operation if the signal information indicates the first value.

8. The terminal device of claim 7, wherein the low power mode of operation is paused for a configured or pre-determined duration.

9. The terminal device of claim 7, wherein the low power mode of operation is paused for an undetermined duration, and wherein the terminal device further comprises:means for receiving signaling information, the signaling information indicating a resumption of the low power mode of operation; andmeans for resuming the low power mode of operation in response to the reception of the signaling information.

10. A method comprising, by a terminal device:detecting a wake up signal during a low power mode operation of the terminal device;decoding signal information from the wake up signal;in response to the detection of the wake up signal, switching a main radio transceiver of the terminal device into an active mode of operation ; andperforming, by the main radio transceiver, a first control channel decoding operation if the signal information indicates a first value, and a second control channel decoding operation different from the first control channel decoding operation if the signal information indicates a second value.

11. A network device (NW) comprising:means for encoding signal information in a wake up signal;means for transmitting the wake up signal to a terminal device during a low power mode operation of the terminal device, the wake up signal triggering a switching of a main radio transceiver of the terminal device into an active mode of operation;means for assigning a first value to the signal information for performance by the terminal device of a first control channel decoding operation, or assigning a second value to the signal information for performance by the terminal device of a second control channel decoding operation different from the first control channel decoding operation.

12. The network device of claim 11, wherein the signal information is addressing information identifying one or more intended recipients of the wake up signal.

13. The network device of claim 12, wherein the first value is a first address value for addressing a set of terminal devices, and the second value is a second address value for addressing one or more terminal devices of the set of terminal devices, and wherein the one or more terminal devices includes the terminal device.

14. The network device of claim 13, wherein the set of terminal devices comprises terminal devices that are in Radio resource Control, RRC, connected state with the network device and that are in a low power mode operation.

15. The network device of any of claims 11 to 14, further comprising:means for transmitting configuration information for configuring the first and second control channel decoding operations.

16. The network device of any of claims 11 to 15, wherein the first control channel decoding operation differs from the second control channel decoding operation by at least one of:a minimum duration of the control channel decoding operation till the terminal device resumes the low power mode of operation;a search space set configuration;a periodicity of the control channel decoding operation while the main radio transceiver is in the active mode of operation; ora number of slots to monitor for the control channel decoding operation while the main radio transceiver is in the active mode of operation.

17. The network device of any of claims 11 to 16, further comprising means for assigning the first value to the signal information for pausing the low power mode of operation of the terminal device.

18. The network device of claim 17, wherein the low power mode of operation is paused for a configured or pre-determined duration.

19. The network device of claim 17, wherein the low power mode of operation is paused for an undetermined duration, and wherein the network device further comprises means for transmitting signaling information, the signaling information indicating a resumption of the low power mode of operation by the terminal device.

20. A method comprising, by a network device:encoding signal information in a wake up signal;transmitting the wake up signal to a terminal device during a low power mode operation of the terminal device, the wake up signal triggering a switching of a main radio transceiver of the terminal device into an active mode of operation; andassigning a first value to the signal information for performance by the terminal device of a first control channel decoding operation, or assigning a second value to the signal information for performance by the terminal device of a second control channel decoding operation different from the first control channel decoding operation.

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