Connected mode discontinuous reception operation

Abstract

CONNECTED MODE DISCONTINUOUS RECEPTION (C-DRX) operations are provided with respect to a User Equipment (UE) in a cellular network for handling first traffic having a first period and second traffic having a second longer period. A single C-DRX configuration is operated between the network and the UE, the single C-DRX configuration having timing parameters defining a repetitive sequence of communication windows, at least one of the timing parameters varying between consecutive communication windows of the repetitive sequence based on both a first period and a second period.

Description

Technical Field

[0001] The present disclosure relates to connected mode discontinuous reception (C-DRX) operation with respect to user equipment (UE) in a cellular network, particularly when handling delay sensitive services. Background Art

[0002] Traffic processing systems within cellular networks are typically designed to map traffic for specific services (e.g., real-time services, such as voice calls, video, or web browsing) to certain Quality of Service (QoS) characteristics, and the cellular network is then configured to meet these characteristics in order to provide a desired user experience. Complexities arise when providing multiple services.

[0003] In 4G Long Term Evolution (LTE) and 5G network architectures, a series of steps are used to achieve QoS characteristics for each service in the downlink at the network. Traffic packets for a specific service are sent from the User Plane Function (UPF) or Packet Gateway (P-GW) via a GTP-U (GPRS Tunneling Protocol - User Data) tunnel to the radio access node (gNB / eNB), where they are processed according to predefined QoS flows, each of which is mapped to a corresponding so-called Data Radio Bearer (DRB). The configuration (features and settings) of the DRB is selected to achieve the QoS parameters. To meet the QoS requirements on the air interface, different QoS flows are typically mapped to separate DRBs. The access node enables radio-related features and packet scheduling differently for each DRB. Each time a service is established, the corresponding configuration is provided to the radio access node. The service is then processed according to these configurations.

[0004] The characteristics of different QoS flows (called 5QI in 5GS and QCI in EPS) are standardized in 3GPP Technical Specification (TS) 23.501 as Table 5.7.4-1: Standardized 5QI to QoS Characteristics Mapping and similarly in TS 23.203 Version 17.0.0 as Table 6.1.7-A. The main attributes of a particular QoS flow (5QI) are: resource type; guaranteed bit rate (GBR) or non-guaranteed bit rate; priority; packet delay budget; packet error rate; and parameters indicating the burstiness of the data (maximum data burst size and averaging window).

[0005] A UE may support different services with different QoS requirements. Handling multiple services being provided simultaneously presents challenges. In particular, certain settings at the lower layers of the protocol stack at the UE are independent of the services being provided. One such setting is Discontinuous Reception in Connected Mode (C-DRX). This setting, once configured, allows the UE to listen to the network radio access node (gNB / eNB) only at predefined times for predefined durations. If no traffic arrives during the predefined duration, the UE enters sleep mode until the next predefined time arrives. C-DRX is configured individually for the UE, but is not set specifically for each traffic flow and does not change between DRBs or traffic flows.

[0006] refer to Figure 1 , shows a schematic diagram of the timing of existing DRX operation for a single business or service. The horizontal axis indicates increasing time and is divided into intervals, each of the same length. These are illustrated by a first cyclic interval 1a (Long DRX Cycle #n) and a second cyclic interval 1b. A first time window 10 during which the UE listens to the network radio access node (i.e., the UE receiver is turned on) starts at a time that is offset 2 (drx-Slot Offest) from the start of the first cyclic interval 1a. The duration 3 of the first time window 10 is defined by drx-onDurationTimer. These timing parameters together define C-DRX operation. The settings and parameters of the existing C-DRX configuration can be found in 3GPP TS 38.331 version 17.3.0, and the formula for calculating the start of drx-onDurationTimer can be found in 3GPP TS 38.321 version 17.3.0, section 5.7.

[0007] The same timing applies to the second cyclic interval 1b (long DRX cycle #n+1), where the UE listens to the network radio access node during the second time window 20. Similarly, the UE listens to the network radio access node during the third time window 30 in the subsequent cyclic interval, where the same timing applies. Outside the specified time window, the UE is in sleep mode to save power. For example, if drx-Slot Offset = 0, long DRX cycle = 20 ms, and DRX-OnDurationTimer = 2 ms, then the UE will be awake for 2 ms every 20 ms to receive data. The network should have data ready for transmission to the UE during each time window (i.e., every 20 ms for this example). If data arrives later than the time window (e.g., at a time of 3 ms from the start of the cycle), the network will need to buffer the data until the next time window begins and the UE wakes up again to receive data (in this example, an additional 17 ms).

[0008] It will therefore be appreciated that C-DRX can operate efficiently for periodic traffic of a single service. In practice, the cyclic interval length is preferably set to match the period of the data (the interval between arrival times of data packets for the service), and the offset and / or on-duration can also be set to match the arrival time of the traffic at the base station. It should be noted that in cases where the traffic is not periodic in nature, the performance of C-DRX may be lower, but there may still be power saving benefits in such cases.

[0009] A particular problem may arise when a UE receives traffic for two services with different periodicities. Figure 2 , Figure 2 The timing of packets arriving at the base station and being transmitted from the base station to the UE under existing C-DRX operation is schematically shown. According to the above example, the UE is configured for C-DRX operation with a long DRX cycle = 20ms and a DRX-OnDurationTimer = 2ms. In other words, the time window during which the UE monitors the network radio access node (base station) occurs once every 20ms and lasts for 2ms each time. The service for the first service (service 1) has a period of 20ms. However, the second service (service 2) has a longer period, specifically 32ms in this example. Under the existing processing method, the C-DRX timing parameters are set according to the shorter period service mode. Therefore, the cyclic interval length is set with the period of the first service, i.e. 20ms.

[0010] However, this results in a delay in the transmission of packets for the second service, which will be referred to Figure 2For discussion. Zero time (t=0) 100 is indicated and the first packet (P1) for service 1101 arrives 20ms later (t=20ms). This coincides with the first time window for UE reception, so P1 is transmitted in the first transmission 121 during the first time window. Subsequently (t=32ms), the first packet (S2 P1) for service 2111 arrives. Because the UE is in sleep mode at this time, the S2 P1 packet is buffered at the base station. The second packet (P2) for service 1102 arrives at the base station at t=40ms, which coincides with the second time window for UE reception. Therefore, both S2 P1 and P2 are transmitted in the second transmission 122 during the second time window. Therefore, there is an 8ms delay in the transmission of S2 P1. The third packet (P3) for service 1103 arrives at the base station at t=60ms, which coincides with the third time window for UE reception. Therefore, P3 is transmitted in the third transmission 123 during the third time window. Later (t = 64 ms), the second packet (S2 P2) for service 2 111 arrives. Because the UE is in sleep mode at this time, the S2 P2 packet is buffered at the base station. The fourth packet (P4) for service 1 104 arrives at the base station at t = 80 ms, coinciding with the fourth time window for UE reception. Therefore, both S2 P2 and P4 are transmitted in the fourth transmission 124 during the fourth time window. Therefore, there is a 16 ms delay in the transmission of S2 P2. This is a significant delay.

[0011] Therefore, existing C-DRX operation with multiple services of different cycles results in buffering data for the service with the longer cycle. In cases where the second service is delay-tolerant (e.g., background traffic or general web browsing), such buffering may be acceptable to the user. This approach enables a simple implementation by providing a single C-DRX configuration to the UE.

[0012] 3GPP is considering ways to handle extended reality (XR) traffic, which can include multiple services with different traffic parameters. A limitation of existing C-DRX implementations is that the UE can only be awake at times defined by an integer number of milliseconds, but the period of XR traffic may be a non-integer number of milliseconds, for example if it depends on the frame rate used by the application codec. For example, a video at 60 frames per second would equal a traffic period of 16.667ms. This has been addressed with a number of proposals in 3GPP working documents: R2-2211180, R2-2211775, R2-2212886, and R2-2212812.

[0013] Some of these documents also consider the problem of services with different characteristics (e.g. different periodicities). In particular, XR services may include video services with shorter periodicities (e.g., about 16 ms) and voice services with longer periodicities (e.g., about 20 ms). These services are not delay tolerant. Known techniques using a single C-DRX configuration with timing parameters corresponding to the most stringent QoS requirements of multiple services introduce buffering delays. 3GPP working document R2-2211775 analyzes existing approaches for handling such services with C-DRX:

[0014] “It has been proposed to allow multiple active DRX configurations to be used simultaneously for different flows with different traffic characteristics. Simultaneous services with different QoS have been supported since LTE Rel-8. It has been assumed that the NW can configure the DRX configuration based on the most stringent requirements, so only one active DRX configuration at a time is sufficient. Having multiple active configurations will result in separate active times, which is less efficient than scheduling bundled data. Furthermore, multiple active configurations make DRX operation more complex and may lead to higher configuration complexity to operate it.”

[0015] Therefore, this document seems to indicate that the existing approach is the best available. However, this would seem to mean that some types of XR traffic cannot be delivered when C-DRX is operating without significant degradation. It would be desirable to allow C-DRX operation while being able to deliver multiple services with delay-sensitive traffic without QoS degradation. Summary of the Invention

[0016] In this context, the present disclosure provides a method for connected mode discontinuous reception (C-DRX) operation with respect to a user equipment (UE) in a cellular network according to claim 1, a computer program according to claim 13, a network entity (or node) of a cellular network according to claim 14, and a UE of a cellular network as defined by claim 15. Further preferred features are disclosed in the following description and with reference to the claims.

[0017] It has been recognized that a single C-DRX configuration can be used for two types of traffic, each with a different cycle. A single C-DRX configuration defines a repeating sequence of communication windows (DRX on-duration), but whereas the existing DRX sequence is the same for each cycle, the DRX timing parameters according to the present disclosure (particularly the cycle length, time duration, and / or on-duration) vary between cycles. This variation depends on the cycles of the two types of traffic. Therefore, the DRX timing parameters are repeated over a longer time frame comprising multiple DRX cycles (i.e., a single C-DRX configuration has multiple associated cycles or is defined by a single cycle that is modulated).

[0018] Advantageously, a single C-DRX configuration requires significantly less processing power and overhead than multiple DRX configurations that are active simultaneously (the UE implements the multiple DRX configurations using separate logical flows). Thus, a single C-DRX configuration can provide the power efficiency benefits of DRX without the QoS degradation associated with existing DRX techniques for handling multiple types of traffic with different cycles. Advantageously, the two types of traffic are delay-sensitive and / or real-time traffic. The cycle length time can be an integer or a non-integer. It will be understood that the techniques according to the present disclosure can be extended to cover more than two types of traffic. The processing according to the present disclosure can be implemented as software (computer program), in a controller, at a network entity (e.g., a radio access node), or in a UE.

[0019] In some embodiments, a single C-DRX configuration can be formed by employing a union (or superposition) of two periodic DRX configurations, specifically a union of a DRX configuration having a cycle length equal to the period of the first traffic and a DRX configuration having a cycle length equal to the period of the second traffic. The on-duration of the DRX configuration having a cycle length equal to the period of the first traffic is advantageously kept constant, and / or the on-duration of the DRX configuration having a cycle length equal to the period of the second traffic is advantageously kept constant. Typically, the on-durations for both DRX configurations are the same. Alternatively, the on-duration of the DRX configuration having a cycle length equal to the period of the first traffic and / or the on-duration of the DRX configuration having a cycle length equal to the period of the second traffic can vary between consecutive communication windows.

[0020] In other embodiments, the cycle length of a single C-DRX configuration is fixed (e.g., equal to the shortest traffic cycle), and the on-duration varies between consecutive communication windows. In particular, the on-duration can be increased so that the end of each communication window matches the cycle of the traffic with the longer (or longest) cycle.

[0021] The instructions for the single C-DRX configuration are advantageously communicated from the network to the UE (in this context, communication means transmitting and / or receiving). This can be done using a Radio Resource Control (RRC) configuration message or a Medium Access Control (MAC) signaling. In one option, the instructions include an indication of the first and second periods (e.g., in the form of timing parameters of a periodic DRX configuration corresponding to traffic characteristics). The UE will then determine the timing of the single C-DRX configuration. In another option, the instructions include timing parameters that fully define the single C-DRX configuration (e.g., multiple sequential on-durations and / or multiple sequential cycle lengths). BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The process of the present disclosure may be put into practice in various ways, one of which will now be described by way of example only and with reference to the accompanying drawings, in which:

[0023] Figure 1 A schematic diagram showing the timing of existing DRX operations for a single service;

[0024] Figure 2 Schematically illustrates the timing of packets arriving at a base station and being transmitted from the base station to a UE under existing C-DRX operation for two services with different cycles;

[0025] Figure 3 Schematically depicts the timing of packets arriving at a base station and being transmitted from the base station to a UE for two services with different cycles under a first C-DRX operation according to the present disclosure;

[0026] Figure 4a schematically depicts the timing of arrival of packets for a first service with a first periodicity among two services at a base station and transmission from the base station to a UE under existing C-DRX operation;

[0027] Figure 4b schematically depicts the timing of packets for a second service having a second different periodicity among two services arriving at a base station and being transmitted from the base station to a UE under existing C-DRX operation;

[0028] Figure 4c Schematically depicts the timing of packets arriving at a base station and being transmitted from the base station to a UE under a second C-DRX operation combined with an existing C-DRX operation according to the present disclosure;

[0029] Figure 4d Schematically depicts the Figure 4c Public C-DRX operation Figure 4a and Figure 4b Existing C-DRX operation.

[0030] Where a drawing refers to a feature that is also shown in another drawing, the same reference numerals have been used. DETAILED DESCRIPTION

[0031] The present disclosure recognizes that traffic for multiple services with different cycles can be sent from the network to the UE using a single C-DRX configuration. Unlike existing C-DRX configurations, in which each cycle has the same timing parameters (e.g., cycle length, on-duration, and / or timing offset), a single C-DRX configuration is proposed in which the parameters are configured to vary. Therefore, the repetitive pattern of the C-DRX configuration does not repeat every cycle, but rather repeats over multiple cycles.

[0032] Two approaches based on this general approach are proposed. In a first approach, the on-duration may be adjusted such that each communication window of a C-DRX configuration covers not only traffic for a higher periodic service but also immediately subsequent traffic for a lower periodic service (or services). In a second approach, a single C-DRX configuration may be established based on the union of two (or more) standard C-DRX configurations. Each standard C-DRX configuration has a single cycle time, on-duration and offset, and at least the cycle time differs between these configurations such that the union of multiple standard C-DRX configurations results in a single C-DRX configuration with an effectively varying cycle duration. The variation in cycle duration has a repeating pattern. Both approaches will be discussed in more detail below.

[0033] In general, a method for C-DRX operation of a UE in a cellular network for processing a first service (a first service) having a first period and a second service (a second service) having a second, longer period can be considered. The method includes operating a single C-DRX configuration between the network and the UE, the single C-DRX configuration having timing parameters that define a repeating sequence of communication windows (each communication window can correspond to a time period during which the UE is configured to listen for transmissions from a radio access node or base station of the network; the network is similarly configured to transmit to the UE only during these time periods). At least one of the timing parameters varies (or is modulated) between consecutive communication windows of the repeating sequence. The timing parameters and / or variations are based on or according to the first period and the second period. For example, one timing parameter can be based on the first period, and / or the variation of another timing parameter can be based on the second period.

[0034] For example, the timing parameters may include one or both of the following: a cycle length time duration; and an on-duration. Another possible timing parameter is an offset time (the time at which a communication window begins after the start of a cycle), although this is typically assumed to be zero. In this case, the cycle length is the time between the start of one communication window and the start of the (immediately following) subsequent communication window. Optionally, the cycle length time has a non-integer value.

[0035] Advantageously, both the first traffic and the second traffic are for services having associated quality of service (QoS) parameters indicative of delay sensitive and / or real-time traffic.

[0036] The processing of the method can be implemented in the form of software, middleware or firmware (computer program), including instructions that, when executed by a processor, cause the processor to control the operation of a device in a cellular network to operate according to the method disclosed herein. Additionally or alternatively, the processing of the method can be implemented in hardware and / or as a device, such as a network entity of a cellular network and / or a UE of a cellular network.

[0037] Reference will again be made below to the general terms of the present disclosure. Meanwhile, further details of specific embodiments will now be discussed.

[0038] refer to Figure 3 The first approach was discussed in Figure 3 Schematically depicts the timing of arrival of packets at a base station and transmission from the base station to a UE for two services with different periodicities under C-DRX operation. In this example, two services are considered: a first XR (e.g., video) service with a periodicity of 16 ms; and a second voice service with a periodicity of 20 ms. Both services are delay-sensitive (i.e., have associated delay-sensitive QoS characteristics). It will be seen that zero time (t=0) 200 is indicated, and that a first packet (P1) for the first service 201 arrives 16 ms later (t=16 ms), a second packet (P2) for the first service 202 arrives 16 ms later (t=32 ms), a third packet (P3) for the first service 203 arrives 16 ms later (t=48 ms), and a fourth packet (P4) for the first service 204 arrives 16 ms later (t=64 ms). Similarly, the first packet (S2 P1) for the second service 211 arrives 20ms after time zero (t=20ms), the second packet (S2 P2) for the second service 212 arrives 20ms later (t=40ms), and the third packet (S2 P3) for the second service 213 arrives 20ms later (t=60ms).

[0039] A single C-DRX configuration between a base station (radio access node) and a UE is proposed. The cycle time for this single C-DRX configuration is set based on the lowest period of multiple services, i.e., 16 ms. As discussed above, the OnDuration time for each cycle of the C-DRX configuration is extended by the period required to receive data belonging to both services within that cycle. In other words, the OnDuration time is allocated depending on the cycle, taking into account the service cycle.

[0040] During the first cycle, the on-duration is set to 4ms. Thus, the first communication window 241 (from t=16ms to t=20ms) can transmit the first packet (P1) for the first service in the first transmission 221 and the first packet (S2P1) for the second service in the second transmission 231.

[0041] For the second cycle (which starts at t=32 ms), the on-duration is now set to 8 ms. Thus, the second communication window 242 (from t=32 ms to t=40 ms) allows the transmission of the second packet (P2) for the first service in the third transmission 222 at the start of the window and the transmission of the second packet (S2 P2) for the second service in the fourth transmission 232 at the end of the window.

[0042] The third cycle starts at t = 48 ms and the on-duration for this is set to 12 ms. This provides a third communication window 243 (from t = 48 ms to t = 60 ms), allowing the third packet (P3) for the first service to be transmitted in the fifth transmission 223 at the start of the window and the third packet (S2 P3) for the second service to be transmitted in the sixth transmission 233 at the end of the window.

[0043] In the fourth cycle (starting at t=64ms and ending at t=80ms), no packet for the second service will arrive. Therefore, there is only a short fourth communication window 244 with a 2ms on-duration, allowing the fourth packet (P4) for the first service to be transmitted in the seventh transmission 224.

[0044] There is also a fifth cycle (not shown) from t = 80 ms to t = 96 ms, in which packets for each of the first service and the second service arrive simultaneously (at t = 80). Thus, the fifth cycle is similar to the fourth cycle in that only a short fifth communication window (not shown) with an on-duration of 2 ms is required to allow transmission of packets for both the first service and the second service.

[0045] It will be understood that the sixth, seventh, eighth, ninth and tenth loops (not shown) are exact repetitions of the first, second, third, fourth and fifth loops, respectively. In fact, this cycle of loops will continue to repeat and therefore does not require further discussion. As can be seen, this approach makes it possible to deliver two services (XR and voice) without any buffering. In practice, the UE is awake for 28ms in every 96ms (or equivalently, the UE is in sleep mode for 68ms in every 96ms). However, during times when no transmission is expected, the UE is forced to listen (awake or not in sleep mode).

[0046] While this is illustrated for services having a particular period, it will be appreciated that similar treatment can be employed for services having different periods. The period need not be an integer value, although the cyclical repeating pattern may be longer if one or more periods are non-integer.

[0047] There are two main drawbacks to this approach. First, requiring the UE to listen when no transmission is expected means that the UE spends a suboptimal amount of time in sleep mode, therefore consuming more battery power than necessary. Second, according to current standards, flexible on-duration (onDurationTimer) settings are not possible within existing C-DRX configuration settings and implementations. It may require considerable redesign of the calculation of how long the "on-duration time" should last. Currently, this timer is specified to have only one value (see 3GPP TS 28.321 version 17.3.0, section 5.7).

[0048] refer to Figure 4a -d to consider the second approach. First refer to Figure 4a , which schematically depicts the timing of packets for a first service with a first cycle in two services arriving at a base station and being transmitted from the base station to a UE under existing C-DRX operation. Figure 3 In the example shown in , the first service has a periodicity of 16 ms and the second service has a periodicity of 20 ms. Both services are delay sensitive (ie have associated delay sensitive QoS characteristics).

[0049] Arriving packets for a first service are shown in the top portion of the figure. Time zero (t=0) 300 is indicated, with the first packet (S1P1) 311 arriving 16 ms later (t=16 ms), the second packet (S1P2) 312 arriving 16 ms later (t=32 ms), the third packet (S1P3) 313 arriving another 16 ms later (t=48 ms), and the fourth packet 314 (S1P4) arriving another 16 ms later (t=64 ms). Below the arriving packets is a standard DRX configuration for the first service 315, with a cycle time of 16 ms and an on-duration of 2 ms. The offset is effectively zero. If only this service were used at a given time, this would effectively be a DRX configuration.

[0050] Next, Figure 4bReference is made to a diagram schematically illustrating the timing of packet arrival at a base station and transmission from the base station to a UE for a second service, one of two services, with a second, different periodicity, under existing C-DRX operation. Arriving packets for the second service are shown in the top portion of the figure, again with zero time (t=0) 300 indicated. A first packet (S2P1) 321 arrives 20 ms later (t=20 ms), a second packet (S2P2) 322 arrives 20 ms later (t=40 ms), a third packet (S2P3) 323 arrives another 20 ms later (t=60 ms), and a fourth packet (S2P4) 324 arrives another 20 ms later (t=80 ms). Similarly, a standard DRX configuration for the second service 325 is shown below the arriving packets, having a cycle time of 20 ms and an on-duration of 2 ms. The offset is effectively zero. Again, if only the second service is used at a certain time, this would effectively be a DRX configuration.

[0051] The proposed approach is based on the union of two standard DRX configurations for two services to generate a single C-DRX configuration. Figure 4c , schematically depicting the timing of arrival of packets for both a first service and a second service with different periods at the base station (in the top portion of the drawing). Also shown is the transmission from the base station to the UE under a second C-DRX operation 340 based on the combination of the existing C-DRX operation according to the present disclosure. This operation 340 is shown in the bottom portion of the drawing, including: a first communication window 341 at t=16ms; a second communication window 342 at t=20ms; a third communication window 343 at t=32ms; a fourth communication window 344 at t=40ms; a fifth communication window 345 at t=48ms; a sixth communication window 346 at t=60ms; a seventh communication window 347 at t=64ms; and an eighth communication window 348 at t=80ms. The first, third, fifth, seventh and eighth communication windows are used for the first service, and the second, fourth, sixth and eighth communication windows are used for the second service (so that the eighth communication window is used for both services). The open duration of all communication windows is 2ms.

[0052] Figure 4d Schematically depicts the Figure 4c The public relative to C-DRX operation Figure 4a and Figure 4b As can be seen more clearly, the second C-DRX operation 340 consists of a combination or overlay of the standard DRX configuration for the first service 315 and the standard DRX configuration for the second service 325.

[0053] This approach has significant benefits compared to data bundling (using a single C-DRX configuration with a single fixed cycle time for each cycle and buffering data until the next communication window). As explained previously, data bundling causes buffering of data and may not be acceptable for traffic from more than one delay sensitive service. For example, an XR application and another real-time service (e.g. voice) running simultaneously will have degraded QoS and user experience with existing approaches. The approach proposed above (in which a single C-DRX configuration is based on the union of two standard DRX configurations as needed) does not require data buffering and is also advantageous compared to using multiple simultaneously active DRX configurations, which is complex to implement for the network and UE due to processing requirements and traffic organization. Similar considerations can be applied at the base station, although the processing capabilities and / or power efficiency at the base station may be higher.

[0054] In contrast, the approach of Figure 4 does not require a significant impact on current C-DRX operation. The duration of the "On Duration Timer" (see 38.321 Section 5.7) does not need to be changed, and the approach can be introduced regardless of whether an integer or non-integer value is used for the cycle length. In addition, the UE is awake only for 16 ms out of every 96 ms (or equivalently, the UE is in sleep mode for 80 ms out of every 64 ms). Note that a UE in C-DRX mode will be awake regardless of whether packets are actually sent from the base station. The UE wakes up according to the provided C-DRX configuration.

[0055] Referring again to the general scope of the present disclosure, as discussed above, further optional, preferred and / or advantageous details may be considered.

[0056] In some embodiments, the cycle length time is changed so that the repeating sequence of the communication window includes a combination (superposition) of a first periodic sequence of communication windows according to a first cycle and a second periodic sequence of communication windows according to a second cycle. Preferably, the first periodic sequence of communication windows has a first fixed on-duration, and the second periodic sequence of communication windows has a second fixed on-duration. The first on-duration and the second on-duration are advantageously the same.

[0057] In other embodiments, the cycle length time is fixed. The on-duration time is then advantageously varied between successive communication windows. Preferably, the cycle length time is based on the first period.

[0058] Before returning again to the general scope of the present disclosure, further specific details will now be discussed.

[0059] In all implementations according to the present disclosure, the communication or signaling of the parameters for a single C-DRX configuration should be considered. Radio Resource Control (RRC) configuration messages are typically used to signal the C-DRX settings, but Medium Access Control (MAC) signaling may be used. For the first approach (where the OnDuration is adjusted between cycles), it has been noted above that current C-DRX configuration signaling may not be suitable. However, one approach to address this may be to specify multiple OnDuration values ​​to be used in consecutive cycles. However, this would require modifications to the 3GPP standard.

[0060] For the second approach (where a single C-DRX configuration is formed by the union of multiple standard C-DRX configurations), existing signaling can be used to inform the UE of each standard C-DRX configuration. The UE can then be instructed to generate timing for the single C-DRX configuration itself based on the signaled information. Alternatively, a new form of signaling can be used to inform the UE of the timing parameters of the single C-DRX configuration to be used. This can indicate a series of cycle length times to be applied in sequence (similar to the proposal for signaling with respect to the first approach discussed above, but with respect to cycle lengths rather than on-durations).

[0061] Again referring to the general implications of the previous discussion, further optional features may be considered. For example, the method (or process) may include communicating instructions for a single C-DRX configuration from the network to the UE. In some embodiments, rather than operating a single C-DRX configuration, an independent aspect of the present disclosure may be to communicate instructions for a single C-DRX configuration. With respect to this aspect, any details (optional or otherwise) regarding the operational aspects of the present disclosure may also be applied to the communication aspects. In addition, combinations of the two aspects are possible.

[0062] The instruction may include an indication of the first period and the second period (e.g., in the form of a first cycle length time and a second cycle length time). The UE may then determine the timing of the repetition sequence of the communication window based on the instruction. For example, the UE may calculate the union of the two DRX configurations based on the communicated period.

[0063] In some embodiments, the instructions include timing parameters that completely define the timing of the repeating sequence of the communication window. This may require specific signaling of the timing parameters of a single C-DRX configuration (e.g., in the form of multiple cycle length times and / or on-durations).

[0064] Any of the methods described herein may be implemented as a computer program. The computer program may be configured to control an MS, a UE, and / or a network node or entity to perform any method according to the present disclosure. A network node of a cellular network may also be provided, which is configured to operate according to certain methods disclosed herein. For example, the network node may include a processor and at least one communication interface, in particular including one or both of a transmitter and a receiver. A UE may also be provided, which is configured to operate according to certain methods disclosed herein. The UE may also include a processor and at least one communication interface, in particular including one or both of a transmitter and a receiver.

[0065] Although specific embodiments have now been described, it will be appreciated by those skilled in the art that various modifications and variations are possible. For example, although the present disclosure has been described with respect to existing network architectures, it will be appreciated that changes to the architecture (and / or terminology) are possible, but the present disclosure may still be applicable in such cases. Although two processing methods for changing timing parameters (on duration and / or cycle length) have been considered, other processing methods may be considered by those skilled in the art (e.g., changing the offset rather than the cycle length may be possible for some period combinations). In the case of more than two services (and / or business types), it may also be possible to implement processing methods according to the present disclosure. In addition, a combination of any specific features shown with reference to one embodiment (or aspect) or with reference to multiple embodiments (or aspects) is also provided, even if the combination has not been explicitly described in detail herein.

Claims

1. A method for connected mode discontinuous reception (C-DRX) operation with respect to a user equipment (UE) in a cellular network for processing first traffic having a first period and second traffic having a second, longer period, the method comprising: A single C-DRX configuration is operated between the network and the UE, the single C-DRX configuration having timing parameters defining a repeating sequence of communication windows, at least one of the timing parameters varying between consecutive communication windows of the repeating sequence based on both a first period and a second period.

2. The method according to claim 1, wherein The timing parameters include one or both of the following: cycle length time duration; and the duration of the on time.

3. The method according to claim 2, wherein: The cycle length time is changed such that a repeating sequence of communication windows comprises a union of a first periodic sequence of communication windows according to the first period and a second periodic sequence of communication windows according to the second period.

4. The method according to claim 3, wherein: The first periodic sequence of communication windows has a first fixed on-duration and the second periodic sequence of communication windows has a second fixed on-duration.

5. The method according to claim 2 or claim 3, wherein: The on-duration varies between consecutive communication windows.

6. The method according to claim 5, wherein: The cycle length time is fixed, and / or wherein the cycle length time is based on the first period.

7. The method according to any one of claims 2 to 6, wherein: The cycle length time has a non-integer value.

8. The method according to any preceding claim, further comprising: Instructions for the single C-DRX configuration are communicated from the network to the UE.

9. The method according to claim 8, wherein The instructions include indications of a first period and a second period, and the UE determines a timing of a repeating sequence of a communication window based on the indications.

10. The method according to claim 8, wherein The instructions include timing parameters that completely define the timing of the repeating sequence of communication windows.

11. The method according to any one of claims 8 to 10, wherein: The instructions are conveyed in a Radio Resource Control (RRC) configuration message or in Medium Access Control (MAC) signaling.

12. A method according to any preceding claim, wherein: Both the first traffic and the second traffic are for services having associated quality of service (QoS) parameters indicating delay sensitive and / or real-time traffic.

13. A computer program comprising instructions which, when executed by a processor, cause the processor to control the operation of a device in a cellular network to operate according to the method of any preceding claim.

14. A network entity of a cellular network configured to operate according to the method of any one of claims 1 to 12.

15. User Equipment (UE) of a cellular network, configured to operate according to the method of any one of claims 1 to 12.

Images