Efficient receiver operation

Abstract

System and method for managing user equipment, UE, in a telecommunications network, the UE having a first receiver (40 Fig 2) and a second receiver (50 Fig 2), comprising the UE receiving a first sign

Description

Field of the Invention The present invention relates to a system, method, and user equipment (UE) for waking up the UE more effectively and efficiently by improving UE operating efficiency and power management, especially regarding receiver configuration. Background of the Invention The battery life of mobile devices or user equipment (UE) is a consideration in 5G systems together with throughput, latency, and reliability. Many operations carried out within individual UEs can affect their battery life. Therefore, there is an aim to achieve improved energy efficiency and so reduce battery consumption. Study Item TR 38.840 in Release 16 (Rel-16) has led to the adoption of different techniques to reduce the UE’s power consumption and RP-221543 has introduced further techniques. In both Release 16 and 17, it was recognized that one procedure that consumes considerable energy in a UE is the paging procedure. The UE can be configured with particular lengths of wake up periods (e.g., in terms of discontinuous reception or DRX cycle). During these times, the UE is able to receive paging signals. The DRX cycle can be extended to allow the UE to sleep for longer periods of time and reduce power consumption, but this leads to increased latency, which is undesirable. During periods where there is no signalling or data traffic, the UE needs to periodically wake up (e.g., once per DRX cycle) in order to perform coarse synchronization by measuring a synchronization block, so that it can receive a paging message (should one be sent). Figure 1 illustrates this procedure and how the UE changes the power mode of the receiver from deep sleep (DS) to a light sleep (LS) period when it can receive a synchronisation signal block (SSB) burst (where an energy overhead occurs) and back into the DS power mode (see the timing diagram A in Figure 1). The SSB and PO duration may be variable, depending on the Subcarrier Spacing and Cyclic Prefix length. This may be configured by the network. Therefore, Figure 1 illustrates an example configuration. In Release 17 a new behaviour was introduced involving Paging Early Indication (PEI), as shown in timing diagram B in Figure 1, where the base station (gNB) or the core network indicates to the UE whether to monitor for any Paging Occasions (PO) or not. The PEI indicates to the UE whether or not it is likely to be paged and for the UE to select a power mode appropriately. As shown in timing diagram B of Figure 1, the PEI indicates to the UE not monitor for a Paging Occasion and so the receiver can enter a deep sleep mode and reduce its power consumption. In Release 18, a new approach requires an additional new low power receiver within the UE. This low power or secondary receiver is separate from the main or primary receiver. When the secondary receiver receives a signal, it wakes the primary receiver. For example, this can occur when the network needs to page the UE (or for other reasons). This secondary or Low Power Wake Up Receiver (LP-WUR) may need to monitor an ultra low power Wake Up Signal (LP-WUS) sent by the base station (gNB) and this can indicate whether or not to wake up the main or primary receiver (allowing the primary receiver to stay in deep sleep mode in the meantime). When not in connected mode (i.e., idle or inactive modes) the UE can determine whether or not the serving base station can adequately provide services to the UE. The UE does this by making regular signal level measurements. For example, these may be inter-frequency measurements or intra-frequency measurements. When the signal drops below a certain threshold value then the UE can also start to make signal measurements on signals received from neighbouring cells. The accuracy of these measurements is important as they determine how and when the UE commences a cell reselection process. The measurements are made using the primary receiver to maintain accuracy, but waking up the primary receiver at the optimum time itself requires using accurate a more power-hungry operations within the UE. Therefore, there is required a method and system that overcomes these problems. Summary of the Invention User equipment (UE), such as a mobile telephone or loT device, contains a primary or main receiver (that is used to communicate with a gNB or base station or a telecommunications network) and a secondary receiver. The secondary or low power receiver uses much less power than the main receiver but cannot receive the majority of signals used to implement cellular communications. The primary receiver can change from operating in a high power mode, where it can receive signals from a base station to a low power mode where it cannot. It may also have other intermediate power mode(s). When signal levels measured by the UE in non-connected mode (e.g., idle or inactive mode) are at a high level (e.g., because the UE is close to the centre of a cell) then the lower accuracy signal (e.g., dB) measurements are sufficient as the signal levels may be well within a range (e.g., above -60dB to -80dB) that does not require the UE to start making measurements from neighbouring cells. This is because it is unlikely that cell or base station reselection will be required. Therefore, the UE can use the secondary (lower power) receiver to make signal level measurements (from the serving cell or base station). This has the benefit of saving power and resources as the main or primary receiver can remain in a lower power or sleep mode. However, when the signal level measured by the secondary receiver falls to or below a first (predetermined or definable) threshold level (e.g., -79dB) then the main receiver can be activated, woken, or otherwise powered up and take over obtaining signal measurements from the secondary receiver. The UE has two further modes of operation. A low power mode may be used when channel and signal conditions are good, as accuracy and reliability are less important under these conditions. Therefore, battery power may be saved when the UE is operating under these conditions. However, if channel and signal conditions deteriorate sufficiently or to a particular threshold then the lower accuracy and reliability of the low power mode can no longer be used and so the UE switches to a higher power mode (using more power than the low power mode). In the low power mode, a first modulation type of signal can be demodulated by the UE (e.g., on / off keying). Furthermore, a synchronisation signal requiring lower power or fewer system resources, e.g., the Low-Power Synchronization Signal (LP-SS), can be used in the low power mode. In the high power mode, a second modulation type of signal can be demodulated by the UE, e.g., orthogonal frequency division multiplexing (OFDM) or frequency shift keying (FSK). In the high power mode, the synchronisation signal may be a signal that has higher power requirements, such as synchronisation signal block (SSB). When the channel or signal conditions improve then the UE can switch back to the low power mode and associated demodulation type and synchronisation signal. In either the low power mode or the high power mode, the UE may wake up its primary receiver. Doing so at an appropriate time means that lower latency and reliability can be maintained without using excessive power. The need to wake up the primary receiver is less likely when the channel or signal conditions are good (and so less reliable measurements are still acceptable) but becomes more likely when conditions deteriorate. Switching to the higher power mode (for modulation and synchronisation) when signal conditions become more challenging results in the primary receiver being woken up based on more accurate information and so closer to or at an optimum time. The base station sends the same LP-WUS signals whatever mode of operation the UE is using. The transmitted signal has the more complex modulation (e.g., OFDM) overlayed less the complex or less power-hungry modulation (e.g., OOK). For example, the OFDM modulation may be contained within the “on” region of the OOK signal. In accordance with a first aspect there is provided a method for managing user equipment, UE, in a telecommunications network, the UE having a primary receiver and a secondary receiver, the method comprising the steps of: the UE receiving a first signal, a second signal and a third signal from a serving base station using the secondary receiver, wherein the first signal is modulated simultaneously according to a first modulation type and a second modulation type, wherein the second signal is associated with the first modulation type, and the third signal is associated with the second modulation type; the UE operating in a first demodulation mode corresponding to the first modulation type, demodulating the first signal according to the first modulation type to obtain information and measuring one or more signal attributes of the second signal; determining a condition of the second signal; when the condition of the second signal falls below a first threshold, changing operation of the UE to a second demodulation mode corresponding to the second modulation type, demodulating the first signal according to the second modulation type to obtain information and measuring one or more signal attributes of the third signal, wherein operation of the UE in the first demodulation mode consumes less power than when operating the UE in the second demodulation mode; and waking up the primary receiver based on any one or more of: the information obtained by demodulating first signal, and / or the one or more signal attributes of the second or third signals. Therefore, power can be preserved but the primary receiver is still woken up closer to or at an appropriate time so that data transmissions are not missed. Preferably, the first signal mat be a low-power wake up signal, LP-WUS, the second signal is a low-power synchronisation signal, LP-SS, and the third signal is a LP-SS or a synchronisation signal block, SSB. Other signal types may be used. Advantageously, the secondary receiver may have a sensitivity for signal measurement lower than the primary receiver and / or the secondary receiver consumes less power than the primary receiver when making signal measurements. This saves power with sacrificing accuracy or measurements when needed the most. Preferably, the secondary receiver may be a low-power wake up receiver, LP-WUR and the primary receiver is a main receiver of the UE. Optionally, the method may further comprise the step of using the primary receiver instead of the secondary receiver to receive the first signal, the second signal and / or the third signal. Therefore, the improved accuracy and sensitivity of the primary receiver is used when needed. Optionally, the second modulation of the signal is overlaid on the first modulation of the signal. This is one way of simultaneously modulating the first signal with both modulation types. Optionally, the method may further comprise the steps of: determining a condition of the third signal; and when the condition of the third signal rises above a second threshold, changing operation of the UE to the first demodulation mode, demodulating the first signal according to the first modulation type to the obtain information and measuring one or more signal attributes of the second signal. Therefore, the method may move in both directions when the signal and / or channel conditions change, deteriorate and improve. Optionally, the method may further comprise the step of changing a mode of the primary receiver to a sleep mode based on any one or more of: the information obtained by demodulating first signal, and / or the one or more signal attributes of the second or third signals. Wake up may refer to change a power mode of the primary receiver from a low or no power mode to a higher power mode or fully operation mode. Switching to a sleep mode may move from the higher power mode to the lower or no (switched off) power mode. Preferably, the first signal or the second signal may be a reference signal transmitted by the serving base station. Advantageously, the UE may be operating in Idle or Inactive mode. In connected mode the telecommunications network may control some or all of the modes of the UE. Optionally, the first and / or second threshold may be defined using a radio resource control, RRC, parameter. Therefore, the telecommunications network may configure one or more UEs so that their operation may be tuned or optimised at different times or when there are different radio traffic conditions, for example. Optionally, the first demodulation mode may be on / off keying, OOK, and the second demodulation mode is frequency shift keying, FSK, or orthogonal frequency division multiplexing, OFDM. Other modulation types may be used, where the first demodulation mode uses less power or resources than the second demodulation mode. Optionally, the condition of the second signal or the third signal may be any one or more of: reference signal received power (RSRP), received signal strength indicator, RSSI, reference signal received quality (RSRQ), low power RSRP (LP-RSRP), low power RSSI (LP-RSSI), and / or low power RSRQ (LP-RSRQ). Other metrics or measurement types may be used to evaluate channel or signal conditions, characteristics, amplitude, and / or quality. According to a second aspect, there is provided a telecommunications system comprising: one or more serving base station; and one or more user equipment, UE, comprising means for carrying out the methods described above. Any number of UEs operating according to the methods and receiving signals from any number of base stations. Preferably, the telecommunications system may be a new radio, NR, telecommunications system. For example, this may be a LTE, 5G, 6G or further technology telecommunications system. In accordance with a third aspect there may be provided a non-transitory computer-readable medium storing software comprising instructions executable by one or more computers which, upon such execution, cause the one or more computers to carry out the methods described above. The methods described above may be implemented as a computer program comprising program instructions to operate a computer. The computer program may be stored on a computer-readable medium, including a non-transitory computer-readable medium. The computer system may include a processor or processors (e.g., local, virtual or cloud-based) such as a Central Processing Unit (CPU), and / or a single or a collection of Graphics Processing Units (GPUs). The processor may execute logic in the form of a software program. The computer system may include a memory including volatile and nonvolatile storage medium. A computer-readable medium (CRM) may be included to store the logic or program instructions. For example, embodiments may include a non-transitory computer-readable medium (CRM) storing software comprising instructions executable by one or more computers which, upon such execution, cause the one or more computers to perform the disclosed methods. Non-transitory CRM may refer to a CRM that stores data for short periods or in the presence of power such as a memory device or Random Access Memory (RAM). For example, a non-transitory computer-readable medium may include storage components, such as, a hard disk (e.g., a magnetic disk, an optical disk, a magneto-optic disk, and / or a solid state disk), a compact disc (CD), a digital versatile disc (DVD), a floppy disk, a cartridge, and / or a magnetic tape. The different parts of the system may be connected using a network (e.g. wireless networks and wired networks). The computer system may include one or more interfaces. The computer system may contain a suitable operating system such as UNIX, Windows (RTM) or Linux, for example. It should be noted that any feature described above may be used with any particular aspect or embodiment of the invention. Brief description of the Figures The present invention may be put into practice in a number of ways and embodiments will now be described by way of example only and with reference to the accompanying drawings, in which: Fig. 1 shows a schematic illustration of the timing of signals between a network and user equipment (UE); Fig. 2 shows a schematic diagram of a system for initiating communications between a network and the UE; Fig. 3 shows a schematic diagram of system for executing the methods; and Fig. 4 shows a flowchart of a method for managing the UE; It should be noted that the figures are illustrated for simplicity and are not necessarily drawn to scale. Like features are provided with the same reference numerals. Detailed description of the preferred embodiments A low power secondary receiver is used to wake up a primary receiver, which has different characteristics to the primary receiver in a new radio (NR) user equipment (UE). Preferably, the secondary receiver has reduced complexity so that the primary receiver can be powered down more often whilst keeping the secondary receiver operational and the overall system can then consume less power. This difference and energy saving can be considerable. The primary receiver is configured to receive certain types of signals (e.g., a first signal type) and the secondary receiver is configured to receive a different type of signals (e.g., a second signal type). Therefore, the secondary receiver (i.e., a Low Power Wake up Receiver - LP-WUR) consumes less power than the primary receiver (e.g., by at least a factor of 10). To allow this lower complexity, the type of signal that is received by the secondary receiver should also follow a simpler design. The characteristics of such a new (second) signal LP-WUS (Low power wake up signal) can comprise but is not limited to: 1) Lower modulation order (OOK, FSK); and 2) Smaller amount of data to be transmitted The second signal type (LP-WUS) may in some situations be a replacement for (or in addition to) the PEI (Paging Early Indication) functionality, as shown in the timing diagram B of Figure 1, or to be used as trigger to monitor one or more Paging Occasion, e.g., by monitoring the Physical Downlink Control Channel (PDCCH) in the primary receiver, as shown in timing diagram A in Figure 1. However, both receivers can measure the signal strengths of each different type of signal. In other words, although the secondary receiver is optimised to receive different signals than the primary receiver, it may still be used to monitor and measure other signal types, including those intended for the primary receiver. The secondary receiver (LP-WUR) can have a simpler architecture, with lower cost and complexity components when compared with the primary receiver, as the demodulation of the wake up signal will not be as complex as the demodulation of a legacy signal received by the primary receiver, e.g., a NR channel / signal. For example, the receiver architecture for the secondary receiver may be based on: 1) RF Envelope detection; 2) Heterodyne architecture with Intermediate Frequency envelope detection; 3) Homodyne / zero-lntermediate Frequency architecture with baseband envelope detection; and 4) FSK (Frequency Shift Keying) receiver. These secondary receiver architectures are optimised for a lower power consumption when compared to the primary receiver, at the cost of lower receiving sensitivity. Primary or main receiver sensitivity values can be found on TS 38.101-1 and can be as low as -96.8 dBm for the reception of a Quadrature phase-shift keying (QPSK) signal for n1 with 15 kHz SCS with a 2RX receiver. For comparison, the type of architectures mentioned above for the secondary receiver can have sensitivity values between -50 to -90 dBm. By having lower receiving sensitivity when compared to the primary receiver, depending on the LP-WUS design, the secondary receiver (LP-WUR) may have coverage performance degradation and so will not always be able to detect the LP-WUS indicating that the UE is to be paged. Therefore, there may be no trigger to wake up the primary receiver and so paging (or other) messages may be missed when transmitted by the base station, gNodeB or gNB. If the UE is not able to be paged due to coverage issues from the non-detection of the LP-WUS, caused by the lower sensitivity of the secondary receiver (LP-WUR), the UE may be left in a state where it doesn’t wake up as it was not triggered by the secondary receiver (LP-WUR). This can leave the UE not able to receive paging messages even in the absence of coverage level issues (i.e., if the primary receiver was in a high power mode). Although the aim of employing a LP-WUR / LP-WUS (second signal type / secondary receiver) mechanism is to wake up the primary or main radio when it is triggered by the network, this does not require the primary receiver to be completely shut down. It will instead change to a deeper sleep state (low power mode) and not be completely shut off. There may be several different power modes or sleep states. An ultra-deep sleep or lowest power mode may be defined relative to a fully active state. The active or highest power state or mode may have a relative power unit of 1. The ultra-deep sleep power state may consume approximately 0.015 times the power of the active state of the primary receiver. This may be found in TR 38.869. Figure 2 shows a schematic diagram of a system 10 that incorporates a UE 20 and a base station (gNB or gNodeB) 30 connected to other parts of the telecommunications network 70. The system 10 may include a plurality of base stations 30 and many UEs 20 but Figure 2 only shows a single UE 20 and base station 30 for simplicity. There may be one or more (a group of) neighbouring base stations (not shown in this figure). These neighbouring base stations provide alternatives to the serving base station (30 in this figure) should signal degradation occur. The primary receiver 40 and the secondary receiver 50 are shown within the UE 20. Both receivers are shown as being connected to antenna 90 of the UE but there may be separate antennas and each receiver may have its own antenna in certain alternative implementations. A processing means 60 is illustrated with the primary receiver 40 but such processing means may be located elsewhere. The base station 30 also has its own processor 80 that controls how and when the first and second signals are sent from the base station 30 using an antenna 85. In Figure 2, the transmission of the first signal 45 is shown between the base station 30 and the primary receiver 40. The second signal type 55 is shown schematically also between the base station 30 and the secondary receiver 50. The secondary receiver 50 is shown in communication with the primary receiver 40. In particular, when the secondary receiver 50 receives the second signal type 55, a trigger 25 is sent from the secondary receiver 50 to the primary receiver 40, which is processed by the processing means 60 of the primary receiver to change the power state of the primary receiver 40 from any low power modes to a high (or higher) power mode enabling the primary receiver 40 to receive the first signal type 45 from the base station 30. The trigger 25 sent from the secondary receiver 50 to the primary receiver 40 can be sent whether or not the secondary receiver 50 receives the wake up (LP-WUS) signal 55 and the ability to send this trigger is utilised in the following description and enhancements. These receiver architectures are aimed to achieve a lower power consumption when compared to the main receiver, at the cost of lower receiving sensitivity. The main or primary receiver 40 sensitivity values can be found on TS 38.101-1 and can be as low as -96.8 dBm for the reception of a QPSK signal for n1 with 15 kHz SCS with a 2RX receiver. For comparison, the sensitivity values for the secondary receiver 50 may be between -50 to -90 dBm. By having lower receiving sensitivity when compared to a main a receiver, depending on the LP-WUS signal design, the LP-WUR may have coverage performance degradation. With the UE 20 in a non-connected mode (e.g., idle mode) serving cell and target cell measurements are obtained by a receiver of the UE 20. The different sensitivity levels of the primary receiver 40 and the secondary (LP-WUR) receiver 50, may be expected to cause difficulties if secondary receiver 40 is responsible for those measurements and also for reselection process. Therefore, in existing implementations, only the primary receiver 40 is used. Any of the described methods may be executed by a computer system. As shown in Figure 3, the computer system 300 includes a number of components including communication interfaces 320, system circuitry 330, input / output (I / O) circuitry 340, display circuitry and interfaces 350, and a datastore 370. The system circuitry 320 can include one or more processors or CPUs 380 and memory 390. The system circuitry 330 may include any combination of hardware, software, firmware, and / or other circuitry. The system circuitry 330 may be implemented, with one or more systems on a chip (SoC), application specific integrated circuits (ASIC), microprocessors, and / or analog and digital circuits. The display circuitry may provide one or more graphical user interfaces (GUIs) 360 and the I / O interface circuitry 340 may include touch sensitive or non-touch displays, sound, voice or other recognition inputs, buttons, switches, speakers, sounders, and other user interface elements. The I / O interface circuitry 340 may include microphones, cameras, headset and microphone input / output connectors, Universal Serial Bus (USB) connectors, and SD or other memory card sockets. The I / O interface circuitry 340 may further include data media interfaces (e.g., a CD-ROM or DVD drive) and other bus and display interfaces. The memory 390 may include volatile (RAM) or non-volatile memory (e.g., ROM or Flash memory). The memory may store the operating system 392 of the computer system 300, applications or software 394, dynamic data 396, and / or static data 398. The datastore or data source 370 may include one or more databases 372, 374 and / or a file store or file system, for example. In current new radio (NR) systems, it is already possible for the network to configure the UE 20 to measure specific reference signals for different operations. For example, the network can provide the UE 20 the configuration to perform Beam Management (BM), Radio Link Monitoring (RLM), and Beam Failure Detection (BFD) measurements based on the transmitted SSB and / or CSI-RS, over a particular measurement window. The network or the UE 20 (in idle or inactive mode) may configure whether the UE 20 would be performing OOK demodulation and / or decoding the OFDM overlayed sequences on the transmitted OOK symbols from the Low-Power Wake up Signal. From the gNB perspective, the same LP-WUS would be transmitted, however from the UE perspective, it receives a command by the network to either decode this signal in a way or the other or makes a decision based on signal or channel conditions. This can be achieved by defining a network parameter such as a RRC (radio resource control) parameter or other higher layer signalling that would configure the UE work in OOK mode or OFDM mode. By reading this configuration the UE 20 can then perform processing of the LP-WUS accordingly. Moreover, depending on the mode that network configures the UE 20 (or that it switches itself based on signal measurements), it can also configure the types of measurements for the UE to perform synchronization in the following way: If the UE 20 is configured to perform OOK demodulation, then the synchronization signal (LP-SS) may be the Low-Power Synchronization Signal that is sent periodically by the network. If the UE 20 is configured to perform OFDM demodulation, then the synchronization signal can (e.g., SSBs) can be based on the existing synchronization blocks transmitted by the network periodically. Having this configuration enables the network to leverage its resources and perform adequate scheduling of the UEs within the network, enabling different use cases for example: UEs in good channel conditions can be configured to perform OOK demodulation and achieve higher power saving. UEs in bad channel conditions can be configured to perform OFDM demodulation and have greater robustness whilst still saving power. Figure 4 shows a flowchart of a method 400 for managing the UE 20. The method 400 may operate continuously with a modulation mode of the UE 20 switching between a first demodulation mode and a second demodulation mode and back again. These modes are switched according to particular channel or signal conditions between the base station or gNB 30 and the UE 20. The first demodulation mode demodulates using a first demodulation type and uses fewer computing resources and / or power than when the UE 20 is in the second demodulation mode, when demodulating according to a second demodulation type. For example, the first demodulation mode may operate a more simple (lower power) demodulation type, such as on / off keying (OOK). The second demodulation mode may be a more complex demodulation type (e.g., requiring more or higher power) such as frequency shift keying (FSK) or orthogonal frequency division multiplexing (OFDM). Furthermore, the first signal may be modulated according to both modulation types simultaneously. For example, the “on” periods of the OOK signal may be modulated with FSK or OFDM. The base station 30 can send the same signal with the UE 20 demodulating the first signal according to its mode. When demodulating according to the second demodulation mode, the UE 20 may need to first demodulate the first signal according to the first demodulation type and then demodulate according to the second demodulation type. In this example scenario, the UE 20 starts by operating in the first demodulation mode (step 405). The first demodulation mode is associated with the second signal. The second demodulation mode is associated with the third signal. Of course, the UE may also start in the second demodulation mode. The UE 20 receives first, second and third signals from the base station 30 and / or telecommunications network 70 at step 410, using the secondary receiver 50. These signals are constantly being transmitted by the base station 30. The UE 20 is in idle or inactive mode so the base station 30 and / or telecommunications network 70 may be unaware of the UE 20 or its configuration. Demodulating according to either mode enables the UE to obtain information from the first signal (step 420). The UE 20 also measures attributes of the second signal (step 425) when in the first demodulation mode (but does not measure attributes of the third signal). This is shown in Figure 4 taking place after the first signal is demodulated but can take place at any time after the UE 20 has received the second signal. The first signal may be the LP-WUS (e.g., for a different UE 20) or a reference signal, the second signal may be a synchronization signal, such as a low-power synchronisation signal (LP-SS). The third signal may be a synchronization signal and may also be a LP-SS or may be a synchronisation signal block (SSB), for example. Attributes of the second signal are measured or determined at step 425. These may be attributes such as any one or more of reference signal received power (RSRP) received signal strength indicator (RSSI), reference signal received quality (RSRQ), low power RSRP (LP-RSRP), low power RSSI (LP-RSSI), and / or low power RSRQ (LP-RSRQ), for example. In other words, these attributes may be used or interpreted to determine a channel or signal condition of the second signal between the UE 20 and the base station 30 (e.g., serving base station). Any one or more of these signal attributes may have an associated first threshold (which may be a collection or set of separate thresholds forming an overall threshold). When the signal condition (e.g., as indicated by the signal attribute(s)) drops below the first threshold (step 430), then the UE 20 is switched to the second demodulation mode (step 435). The second signal may be a LP-SS or similar. Using such a signal may only provide a rough or inaccurate indication of the channel conditions between the base station 30 and the 20. However, because the channel conditions are above the first threshold (indicating good or very good conditions) then a lack of accuracy is less likely to cause the UE 20 to be in an incorrect configuration (i.e., using the secondary receiver 50 when it should be using the primary receiver 40) and experience latency or signal dropouts. In other words, when the channel conditions are good then it matters less that the measurements are inaccurate. Under these conditions, the UE 20 can preserve battery power by being in the first modulation mode without compromising performance. However, when the signal or channel conditions deteriorate, then it becomes more important that the UE 20 is operating in a more appropriate configuration (e.g., that the UE 20 is using its primary receiver 40). These decisions on UE 20 configuration need to be based on more accurate information, which are available by using the second demodulation mode and associated third signal (e.g., SSB rather than LP-SS). Under these signal or channel conditions it becomes more important to obtain accurate information than to preserve battery power. The UE 20 again receives the first, second and third signals (step 410 repeated) but demodulates the first signal according to the second demodulation type (step 440). The UE 20 measures the attributes of the third signal (step 445) rather than the second signal. Similar signal attributes may be measures (e.g., any one or more of RSRP, RSSI, RSRQ, LP-RSRP), LP-RSSI and / or LP-RSRQ). The method 400 may stop at this point or iterate. For example, the signal attributes of the third signal may be compared against a second threshold, which may be the same or different to the first threshold. Having a small difference in thresholds (the second threshold above the first threshold) may avoid rapid switching between modes when the signal conditions are close to a single threshold (hysteresis). If the signal conditions have improved (the signal condition of the third signal is above the second threshold - step 460) then the UE 20 can switch to the first demodulation mode (step 405) and go back to monitoring the second signal conditions and using the first (lower power) modulation mode. At any point in the method 400, the information extracted from the first signal by demodulating it (according to either demodulation type) and / or the attributes of the second and / or third signals (whichever is being monitored according to the demodulation mode of the UE 20) can be used to make a decision (step 450) on waking up the primary receiver 40 (step 455). Once the primary receiver 40 is being used instead of the secondary receiver 50 then further monitoring and decisions can be made on whether to switch back to the secondary receiver 50. However, these steps and thresholds are not shown in the figure for simplicity. The decision on whether to switch to the primary receiver 40 may use the same or different thresholds to those used to switch demodulation mode. Preferably, the demodulation mode switches from first to second mode with the channel and signal in a better condition (as indicated by the signal attributes) than causes the UE 20 to switch from secondary to primary receiver. The method and system may be implemented in hardware, software, or a combination of hardware and software. The method and system may be implemented either as a server comprising a single computer system or as a distributed network of servers connected across a network. Any kind of computer system or other electronic apparatus may be adapted to carry out the described methods. As used throughout, including in the claims, unless the context indicates otherwise, singular forms of the terms herein are to be construed as including the plural form and vice versa. For instance, unless the context indicates otherwise, a singular reference herein including in the claims, such as "a" or "an" (such as an ion multipole device) means "one or more" (for instance, one or more ion multipole device). Throughout the description and claims of this disclosure, the words "comprise", "including", "having" and "contain" and variations of the words, for example "comprising" and "comprises" or similar, mean "including but not limited to", and are not intended to (and do not) exclude other components. Also, the use of “or” is inclusive, such that the phrase “A or B” is true when “A” is true, “B is true”, or both “A” and “B” are true. The use of any and all examples, or exemplary language ("for instance", "such as", "for example" and like language) provided herein, is intended merely to better illustrate the disclosure and does not indicate a limitation on the scope of the disclosure unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the disclosure. The terms “first” and “second” may be reversed without changing the scope of the disclosure. That is, an element termed a “first” element may instead be termed a “second” element and an element termed a “second” element may instead be considered a “first” element. Any steps described in this specification may be performed in any order or simultaneously unless stated or the context requires otherwise. Moreover, where a step is described as being performed after a step, this does not preclude intervening steps being performed. It is also to be understood that, for any given component or embodiment described throughout, any of the possible candidates or alternatives listed for that component may generally be used individually or in combination with one another, unless implicitly or explicitly understood or stated otherwise. It will be understood that any list of such candidates or alternatives is merely illustrative, not limiting, unless implicitly or explicitly understood or stated otherwise. Unless otherwise described, all technical and scientific terms used throughout have a meaning as is commonly understood by one of ordinary skill in the art to which the various embodiments described herein belongs. As will be appreciated by the skilled person, details of the above embodiment may be varied without departing from the scope of the present invention, as defined by the appended claims. For example, whilst the use of the method has been described with reference to a UE, other devices may be used. Many device or UEs maybe present in the telecommunications system as well as many base stations or gNBs. The method has been described with reference to paging messages but other messages may be used. The signals that are measured by either or both of the primary and secondary receivers may include: frequency shift keying (FSK), on / off keying (OOK), and / or orthogonal frequency division multiplexing (OFDM) signals. Whilst the examples provided above relate to telecommunications systems and UEs, the concept may be applied to Wi-Fi and Bluetooth systems and receives with similar benefits. Any one or more of the thresholds may be predetermined or dynamically set by the base station and / or network (e.g., by transmitting updates as RRC parameters). Many combinations, modifications, or alterations to the features of the above embodiments will be readily apparent to the skilled person and are intended to form part of the invention. Any of the features described specifically relating to one embodiment or example may be used in any other embodiment by making the appropriate changes.

Claims

4CLAIMS:

1. A method for managing user equipment, UE, in a telecommunications network, the UE having a primary receiver and a secondary receiver, the method comprising the steps 5 of:the UE receiving a first signal, a second signal and a third signal from a serving base station using the secondary receiver, wherein the first signal is modulated simultaneously according to a first modulation type and a second modulation type, wherein the second signal is associated with the first modulation type, and the third signal is10 associated with the second modulation type;the UE operating in a first demodulation mode corresponding to the first modulation type, demodulating the first signal according to the first modulation type to obtain information and measuring one or more signal attributes of the second signal;deciding whether or not to wake up the primary receiver based on the information15 obtained by demodulating the first signal;determining a condition of the second signal;when the condition of the second signal falls below a first threshold, changing operation of the UE to a second demodulation mode corresponding to the second modulation type, demodulating the first signal according to the second modulation type to 20 obtain information and measuring one or more signal attributes of the third signal, wherein operation of the UE in the first demodulation mode consumes less power than when operating the UE in the second demodulation mode; anddeciding whether or not to wake up the primary receiver based on the one or more signal attributes of the second or third signals.

252. The method according to any previous claim, wherein the first signal is a low-power wake up signal, LP-WUS, the second signal is a low-power synchronisation signal, LP-SS, and the third signal is a LP-SS or a synchronisation signal block, SSB.30 3. The method of claim 1 or claim 2, wherein the secondary receiver has a sensitivityfor signal measurement lower than the primary receiver and / or the secondary receiver consumes less power than the primary receiver when making signal measurements.

4. The method of claim 3, wherein the secondary receiver is a low-power wake up 35 receiver, LP-WUR and the primary receiver is a main receiver of the UE.

5. The method according to any previous claim further comprising the step of using the primary receiver instead of the secondary receiver to receive the first signal, the second signal and / or the third signal.

56. The method according to any previous claim, wherein the second modulation of the signal is overlaid on the first modulation of the signal.

7. The method according to any previous claim further comprising the steps of:10 determining a condition of the third signal; andwhen the condition of the third signal rises above a second threshold, changing operation of the UE to the first demodulation mode, demodulating the first signal according to the first modulation type to the obtain information and measuring one or more signal attributes of the second signal.15CM8. The method according to any previous claim, further comprising the step ofCM changing a mode of the primary receiver to a sleep mode based on any one or more of: the information obtained by demodulating first signal, and / or the one or more signal attributes O) of the second or third signals.

209. The method according to any previous claim, wherein the first signal or the second signal is a reference signal transmitted by the serving base station.

10. The method according to any previous claim, wherein the UE is operating in Idle or 25 Inactive mode.

11. The method according to any previous claim, wherein the first and / or second threshold is defined using a radio resource control, RRC, parameter.30 12. The method according to any previous claim, wherein the first demodulation modeis on / off keying, OOK, and the second demodulation mode is frequency shift keying, FSK, or orthogonal frequency division multiplexing, OFDM,13. The method according to any previous claim, wherein the condition of the second 35 signal or the third signal is any one or more of: reference signal received power, RSRP,CMreceived signal strength indicator, RSSI, reference signal received quality, RSRQ, low power RSRP, LP-RSRP, low power RSSI, LP-RSSI, and / or low power RSRQ, LP-RSRQ.

14. A telecommunications system comprising:5 one or more serving base station; andone or more user equipment, UE, comprising means for carrying out the methodaccording to any previous claim 1.

15. The telecommunications system of claim 14, wherein the telecommunications10 system is a new radio, NR, telecommunications system.

Images