Timing Advance Signaling

Abstract

A client device, a network node device, a method and a computer program are disclosed. The client device may include at least one processor and at least one memory including computer program code. The at least one memory and the computer program code may be configured to, together with the at least one processor, cause the client device to receive a timing advance configuration message from the network node device, wherein the timing advance configuration message includes a plurality of timing advance commands; perform a plurality of consecutive uplink transmissions to the network node device; and apply the plurality of timing advance commands between the plurality of consecutive uplink transmissions.

Description

Technical Field

[0001] The present application generally relates to the field of wireless communications. In particular, the present application relates to a client device and a network node device for wireless communications, and related methods and computer programs. Background Art

[0002] Timing advance can be used to compensate for the propagation delay of transmission between two devices (such as a client device and a network node device). When the propagation delay changes rapidly due to, for example, the movement of one of the devices, it may be beneficial to update the timing advance used more frequently. However, such signaling may also introduce additional overhead and / or increase the power consumption of the device. This may be particularly disadvantageous for low-power applications such as the Internet of Things (IoT). Summary of the invention

[0003] An embodiment of a client device includes at least one processor and at least one memory including computer program code. The at least one memory and the computer program code are configured to, together with the at least one processor, cause the client device to: receive a timing advance configuration message from a network node device, wherein the timing advance configuration message includes a plurality of timing advance commands; perform a plurality of consecutive uplink transmissions to the network node device; and apply the plurality of timing advance commands between the plurality of consecutive uplink transmissions. For example, the client device may compensate for timing drift during the plurality of consecutive uplink transmissions.

[0004] An embodiment of a client device includes components for performing the following operations: receiving a timing advance configuration message from a network node device, wherein the timing advance configuration message includes multiple timing advance commands; performing multiple consecutive uplink transmissions to the network node device; and applying the multiple timing advance commands between the multiple consecutive uplink transmissions.

[0005] In one embodiment, as an alternative or supplement to the above embodiment, the timing advance configuration message further includes an indication of the effective time of the plurality of timing advance commands, and the at least one memory and the computer program code are further configured to, together with the at least one processor, cause the client device to: apply the plurality of timing advance commands according to the indication of the effective time. For example, the client device may appropriately apply the timing advance command to compensate for the timing drift.

[0006] In one embodiment, as an alternative or supplement to the above embodiment, the indication of the effective time includes at least one of the following: multiple effective times corresponding to multiple timing advance commands; or a period value indicating a time period for applying a new timing advance command in the multiple timing advance commands. For example, the client device can efficiently receive the indication of the effective time.

[0007] In one embodiment, as an alternative or supplement to the above embodiment, at least one memory and computer program code are further configured to, together with at least one processor, cause the client device to: transmit a request for uplink transmission to the network node device before receiving the timing advance configuration message. For example, the client device may indicate the need for uplink transmission to the network node device.

[0008] In one embodiment, alternatively or additionally to the above embodiments, the plurality of consecutive uplink transmissions corresponds to a transmission repetition. For example, the client device may compensate for timing drift during the transmission repetition.

[0009] In one embodiment, as an alternative or supplement to the above embodiments, at least one memory and computer program code are further configured to, together with at least one processor, cause the client device to: perform uplink transmission using a narrowband physical uplink shared channel. For example, the client device can perform uplink transmission with improved compatibility.

[0010] In one embodiment, as an alternative or supplement to the above embodiment, at least one memory and computer program code are further configured to, together with at least one processor, cause the client device to: receive a timing advance configuration message using a narrowband physical downlink control channel. For example, the client device can receive a timing advance configuration message with improved compatibility.

[0011] In one embodiment, as an alternative or in addition to the above embodiments, the client device and the network node device are part of a non-terrestrial network. For example, the client device can compensate for timing drift in the non-terrestrial network.

[0012] An embodiment of a network node device includes at least one processor and at least one memory including computer program code. The at least one memory and the computer program code are configured to, together with the at least one processor, cause the network node device to: estimate a timing drift of a client device; determine a plurality of timing advance commands for the client device based on the estimated timing drift; and transmit a timing advance configuration message including the plurality of timing advance commands to the client device. For example, the network node device may

[0013] An embodiment of a network node device includes components for: estimating a timing drift of a client device; determining a plurality of timing advance commands for the client device based on the estimated timing drift; and transmitting a timing advance configuration message including the plurality of timing advance commands to the client device.

[0014] In one embodiment, as an alternative or supplement to the above embodiment, at least one memory and computer program code are further configured to, together with at least one processor, cause the network node device to: determine an indication of a valid time based on the estimated timing drift, wherein the indication of the valid time corresponds to a plurality of timing advance commands, and wherein the timing advance configuration message also includes an indication of the valid time. For example, the network node device may determine the appropriate timing for applying the TA command and signal the information to the client device.

[0015] In one embodiment, as an alternative or supplement to the above embodiment, the indication of the effective time includes at least one of the following: multiple effective times corresponding to multiple timing advance commands; or a period value indicating a time period for applying a new timing advance command in the multiple timing advance commands. For example, the network node device can efficiently signal the appropriate timing for applying the TA command to the client device.

[0016] In one embodiment, as an alternative or supplement to the above embodiment, at least one memory and computer program code are further configured to, together with at least one processor, cause the network node device to: determine a plurality of timing advance commands and / or indications of valid times for the client device in response to receiving a request for uplink transmission from the client device. For example, the network node device may determine the TA command when the client device needs to perform uplink transmission.

[0017] In one embodiment, as an alternative or supplement to the above embodiments, at least one memory and computer program code are further configured to, together with at least one processor, cause the network node device to: determine scheduling parameters for the client device; determine an expected uplink transmission time based on the scheduling parameters; and determine multiple timing advance commands and / or indications of valid times based on the expected uplink transmission time. For example, the network node device can efficiently determine an appropriate TA command.

[0018] In one embodiment, as an alternative or supplement to the above embodiments, at least one memory and computer program code are further configured to, together with at least one processor, enable the network node device to: determine multiple timing advance commands and indications of valid times based at least on the relative position of the network node device and / or a satellite corresponding to the network node device and the client device, and / or the relative motion of the network node device and / or a satellite corresponding to the network node device and the client device. For example, the network node device can efficiently determine an appropriate TA command.

[0019] In one embodiment, as an alternative or supplement to the above embodiment, at least one memory and computer program code are further configured to, together with at least one processor, enable a network node device to: transmit a timing advance configuration message using a narrowband physical downlink control channel. For example, the network node device may transmit a TA configuration message with improved compatibility.

[0020] In one embodiment, as an alternative or supplement to the above embodiments, at least one memory and computer program code are further configured to, together with at least one processor, cause the network node device to: determine a transmission repetition number for uplink transmission; and transmit an indication of the transmission repetition number to the client device. For example, the network node device can efficiently signal the configuration of the uplink transmission to the client device.

[0021] In one embodiment, as an alternative or in addition to the above embodiments, the network node device is part of a non-terrestrial network. For example, the network node device may enable the client device to compensate for timing drift in a NTN scenario.

[0022] An embodiment of a method includes: receiving a timing advance configuration message from a network node device, wherein the timing advance configuration message includes a plurality of timing advance commands; performing a plurality of consecutive uplink transmissions to the network node device; and applying the plurality of timing advance commands between the plurality of consecutive uplink transmissions.

[0023] In one embodiment, as an alternative or supplement to the above embodiment, the timing advance configuration message further includes indications of valid times of multiple timing advance commands, and the method further includes applying the multiple timing advance commands according to the indications of the valid times.

[0024] In one embodiment, as an alternative or supplement to the above-mentioned embodiment, the indication of the valid time includes at least one of the following: multiple valid times corresponding to multiple timing advance commands; or a period value indicating a time period for applying a new timing advance command among multiple timing advance commands.

[0025] In one embodiment, as an alternative or supplement to the above embodiment, the method further includes transmitting a request for uplink transmission to the network node device before receiving the timing advance configuration message.

[0026] In one embodiment, alternatively or additionally to the above embodiments, the plurality of consecutive uplink transmissions corresponds to a transmission repetition.

[0027] In one embodiment, as an alternative or supplement to the above embodiment, the method further includes performing uplink transmission using a narrowband physical uplink shared channel.

[0028] In one embodiment, as an alternative or supplement to the above embodiment, the method further includes receiving a timing advance configuration message using a narrowband physical downlink control channel.

[0029] In one embodiment, as an alternative or in addition to the above embodiments, the method is performed by a client device, and wherein the client device and the network node device are part of a non-terrestrial network.

[0030] An embodiment of a computer program product comprises a program code, wherein the program code is configured to perform a method according to any of the above-mentioned client device-related embodiments when the computer program product is executed on a computer.

[0031] An embodiment of a method includes estimating a timing drift of a client device; determining a plurality of timing advance commands for the client device based on the estimated timing drift; and transmitting a timing advance configuration message including the plurality of timing advance commands to the client device.

[0032] In one embodiment, as an alternative or supplement to the above embodiment, the method also includes determining an indication of a valid time based on the estimated timing drift, wherein the indication of the valid time corresponds to multiple timing advance commands, and wherein the timing advance configuration message also includes an indication of the valid time.

[0033] In one embodiment, as an alternative or supplement to the above-mentioned embodiment, the indication of the valid time includes at least one of the following: multiple valid times corresponding to multiple timing advance commands; or a period value indicating a time period for applying a new timing advance command among multiple timing advance commands.

[0034] In one embodiment, alternatively or additionally to the above embodiments, the method further comprises determining a plurality of timing advance commands and / or indications of validity times for the client device in response to receiving a request for uplink transmission from the client device.

[0035] In one embodiment, as an alternative or supplement to the above-mentioned embodiment, the method also includes: determining scheduling parameters for the client device; determining an expected uplink transmission time based on the scheduling parameters; and determining multiple timing advance commands and / or indications of valid times based on the expected uplink transmission time.

[0036] In one embodiment, as an alternative or supplement to the above-mentioned embodiment, the method also includes: determining multiple timing advance commands and indications of effective time based at least on the relative position of the network node device and / or the satellite corresponding to the network node device and the client device, and / or the relative movement of the network node device and / or the satellite corresponding to the network node device and the client device.

[0037] In one embodiment, as an alternative or supplement to the above embodiment, the method further includes transmitting the timing advance configuration message using a narrowband physical downlink control channel.

[0038] In one embodiment, as an alternative or in addition to the above embodiment, the method further includes: determining a transmission repetition number for uplink transmission; and transmitting an indication of the transmission repetition number to the client device.

[0039] In one embodiment, as an alternative or supplement to the above embodiments, the method is performed by a network node device, and wherein the network node device is part of a non-terrestrial network.

[0040] An embodiment of a computer program product comprises a program code, wherein the program code is configured to perform a method according to any of the above network node device-related embodiments when the computer program product is executed on a computer. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The accompanying drawings, which are used to provide a further understanding of the embodiments and constitute a part of this specification, illustrate the embodiments and together with the description help explain the principles of the embodiments. In the drawings:

[0042] Figure 1 An example embodiment of the subject matter described herein is shown, which illustrates a client device;

[0043] Figure 2 An example embodiment of the subject matter described herein is shown, which illustrates a network node device;

[0044] Figure 3 A comparative example of the subject matter described herein is shown, which illustrates a diagram of transmission repetition;

[0045] Figure 4 An example embodiment of the subject matter described herein is shown, which shows a diagram of transmission repetition with TA compensation;

[0046] Figure 5 An example embodiment of the subject matter described herein is shown, which shows a signaling diagram;

[0047] Figure 6 An example embodiment of the subject matter described herein is shown, which shows a flow chart;

[0048] Figure 7 An example embodiment of the subject matter described herein is shown, which shows a flow chart of a method; and

[0049] Figure 8 An example embodiment of the subject matter described herein is shown, which shows a flow chart of a method.

[0050] In the drawings, the same reference numerals are used to denote the same parts. DETAILED DESCRIPTION

[0051] Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings. The detailed description provided below in conjunction with the accompanying drawings is intended as a description of this example and is not intended to represent the only form in which this example can be constructed or utilized. This description sets forth the functions of the example and the sequence of steps for constructing and operating the example. However, the same or equivalent functions and sequences may be implemented by different examples.

[0052] Figure 1 is a block diagram of a client device 100 according to an example embodiment.

[0053] The client device 100 includes one or more processors 101 and one or more memories 102 including computer program code. The client device 100 may also include a transceiver 103 and other elements, such as an input / output module ( Figure 1 not shown) and / or communication interface ( Figure 1 not shown).

[0054] According to an example embodiment, at least one memory 102 and computer program code are configured to, together with at least one processor 101, cause the client device 100 to receive a timing advance (TA) configuration message from a network node device. The TA configuration message may include a plurality of TA commands.

[0055] The client device 100 may use, for example, the transceiver 103 to receive the TA configuration message.

[0056] A plurality of TA commands may also be referred to as a group of TA commands, a string of TA commands, etc. A TA command may also be referred to as a TA, a TA value, etc.

[0057] The client device 100 may receive the TA configuration message as part of another message or as a separate message. For example, the client device 100 may receive the TA configuration message as part of a scheduling message for an uplink transmission. Such a scheduling message may indicate, for example, a modulation and coding scheme for the uplink transmission, resources allocated for the uplink transmission, and / or a number of transmission repetitions for the uplink transmission.

[0058] The client device 100 may receive the TA configuration message using, for example, a narrowband physical downlink control channel (NPDCH).

[0059] The client device 100 may perform multiple consecutive uplink transmissions to the network node device. The client device 100 may apply multiple TA commands between the multiple consecutive uplink transmissions. The timing advance configuration message may also include an indication of the validity time of the multiple timing advance commands. The client device 100 may apply the multiple timing advance commands according to the indication of the validity time.

[0060] The indication of the valid time may include a plurality of valid times corresponding to the plurality of timing advance commands. Each of the plurality of valid times may correspond to a TA command in the plurality of TA commands. The plurality of valid times may indicate to the client device 100 at what time the client device 100 should use each of the plurality of TA commands. Alternatively, each of the plurality of valid times may indicate a time window during which a corresponding TA command in the plurality of TA commands is valid.

[0061] Alternatively or additionally, the indication of the validity time may include a period value indicating a time period for applying a new timing advance command from among the plurality of timing advance commands. The period value may be expressed relative to, for example, time, a measurement gap, or a transmission repetition. For example, the period value may indicate that the client device 100 should apply a new TA command every second, every other transmission gap, or every other transmission repetition.

[0062] Alternatively, the network node device may not transmit an indication of the validity time to the client device 100. Instead, the client device 100 may, for example, be preconfigured to apply a new TA command from among the plurality of TA commands at a preconfigured period.

[0063] The multiple consecutive uplink transmissions may correspond to, for example, transmission repetitions.Alternatively or additionally, the multiple consecutive uplink transmissions may correspond to transmissions of some large amount of data that has been split into multiple uplink transmissions.

[0064] The multiple TA commands in the TA configuration message may, for example, include a TA command for each transmission repetition. Furthermore, the indication of the validity time may indicate that the client device 100 should apply a new TA command at the start of each transmission repetition, at the end of each transmission gap, at the end of every other transmission gap, etc. Alternatively, the client device 100 may use multiple TA commands in some other manner as indicated by the indication of the validity time.

[0065] For example, the client device 100 may transmit a request for uplink transmission to the network node device before receiving the timing advance configuration message.

[0066] The network node device may respond to the request for uplink transmission by scheduling the uplink transmission and by transmitting a timing advance configuration message to the client device 100 .

[0067] The client device 100 and the network node device may be part of a non-terrestrial network (NTN). For example, the client device 100 may operate in the NTN and the network node device may include a satellite of the non-terrestrial network, or the network node device may be located on the earth and the satellite may amplify and forward signals from / to the network node device.

[0068] The client device 100 may include, for example, an Internet of Things (IoT) device, such as a narrowband Internet of Things (NB-IoT) device or an enhanced machine type communication (eMTC) device. The network node device may be used as a base station included in a satellite, such as a gNB.

[0069] The client device 100 may perform uplink transmissions using, for example, a narrowband physical uplink shared channel (NPUSCH).

[0070] Although client device 100 is depicted as including only one processor 101, client device 100 may include more processors. In one embodiment, memory 102 can store instructions, such as an operating system and / or various applications.

[0071] In addition, the processor 101 is capable of executing the stored instructions. In one embodiment, the processor 101 can be implemented as a multi-core processor, a single-core processor, or a combination of one or more multi-core processors and one or more single-core processors. For example, the processor 101 can be implemented as one or more of various processing devices, such as a coprocessor, a microprocessor, a controller, a digital signal processor (DSP), a processing circuit system with or without an accompanying DSP, or various other processing devices, including integrated circuits, such as application-specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), microcontroller units (MCUs), hardware accelerators, special-purpose computer chips, etc. In one embodiment, the processor 101 can be configured to perform hard-coded functions. In one embodiment, the processor 101 is implemented as an executor of software instructions, wherein the instructions can specifically configure the processor 101 to perform the algorithms and / or operations described herein when the instructions are executed.

[0072] The memory 102 may be implemented as one or more volatile memory devices, one or more non-volatile memory devices, and / or a combination of one or more volatile memory devices and non-volatile memory devices. For example, the memory 102 may be implemented as a semiconductor memory (such as a mask ROM, a PROM (programmable ROM), an EPROM (erasable PROM), a flash ROM, a RAM (random access memory), etc.).

[0073] The client device 100 may be any of various types of devices that are used directly by an end-user entity and are capable of communicating in a wireless network, such as a user equipment (UE). Such devices include, but are not limited to, smartphones, tablets, smart watches, laptops, Internet of Things (IoT) devices, Narrowband Internet of Things (NB-IoT) devices, enhanced machine type communication devices, etc.

[0074] Figure 2 is a block diagram of a network node device 200 according to an example embodiment.

[0075] The network node device 200 includes one or more processors 201 and one or more memories 202 including computer program code. The network node device 200 may also include a transceiver 203 and other elements, such as an input / output module ( Figure 2 B) and / or communication interface ( Figure 2 not shown in B).

[0076] According to an example embodiment, the at least one memory 202 and the computer program code are configured to, together with the at least one processor 201 , cause the network node device 200 to estimate a timing drift of the client device 100 .

[0077] For example, the network node device 200 may estimate a timing drift occurring during a plurality of consecutive uplink transmissions.

[0078] The network node device 200 may determine a plurality of timing advance commands for the client device 100 based on the estimated timing drift. The plurality of TA commands may compensate for the timing drift.

[0079] The network node device 200 may transmit a timing advance configuration message including a plurality of timing advance commands to the client device 100 .

[0080] The network node device 200 may determine an indication of a validity time based on the estimated timing drift, wherein the indication of the validity time corresponds to a plurality of timing advance commands, and wherein the timing advance configuration message further comprises the indication of the validity time.

[0081] The valid time may include at least one of: a plurality of valid times corresponding to a plurality of timing advance commands, or a period value indicating a time period for applying a new timing advance command from among the plurality of timing advance commands. Thus, the indication of the valid time may include, for example, an explicit list of valid times, or the indication of the valid time may indicate a period during which the TA command should be changed.

[0082] The multiple TA commands may include a TA command that repeats for each transmission of the uplink transmission. In addition, the multiple valid times may indicate that the client device 100 should use a new TA command at the start of each transmission repetition. Alternatively, the multiple valid times may indicate that the client device 100 should use multiple TA commands in some other manner.

[0083] The network node device 200 may transmit the TA configuration message as part of another message or as a separate message. For example, the network node device 200 may transmit the TA configuration message as part of a scheduling message for uplink transmission. Such a scheduling message may indicate, for example, a modulation and coding scheme for uplink transmission, resources allocated for uplink transmission, and / or a number of transmission repetitions for uplink transmission.

[0084] The network node device 200 may receive uplink transmissions from the client device 100. The client device 100 may use multiple TA commands for transmission repetitions during uplink transmissions.

[0085] The network node device 200 may transmit the TA configuration message using, for example, a narrowband physical downlink control channel.

[0086] For example, the network node device 200 may determine an indication of a plurality of timing advance commands and / or validity times for the client device 100 in response to receiving a request for uplink transmission from the client device 100 .

[0087] For example, the network node apparatus 200 may determine scheduling parameters for the client device.The network node apparatus 200 may determine the expected uplink transmission time based on the scheduling parameters.

[0088] The network node device 200 may determine a plurality of timing advance commands and / or indications of validity times based on the expected uplink transmission time. For example, the network node device 200 may determine the timing drift of the client device 200 based on the duration of the uplink transmission. Thus, the network node device 200 may infer appropriate TA commands and / or indications of validity times to compensate for the timing drift.

[0089] For example, the network node device 200 may calculate scheduling parameters for uplink transmission and transmit a message indicating the scheduling parameters and the TA configuration message to the client device 100 in a single message or separate messages.

[0090] The network node device 200 may determine multiple timing advance commands and indications of valid times, for example based at least on the relative positions of the network node device 200 and / or satellites corresponding to the network node device 200 and the client device 100, and / or the relative motion of the network node device 200 and / or satellites corresponding to the network node device 200 and the client device 100.

[0091] The network node device 200 and / or the client device 100 may include, for example, a global navigation satellite system (GNSS) capability. Therefore, the network node device 200 may know the location and / or movement of the client device 100. Therefore, the network node device 200 may predict appropriate TA commands during uplink transmissions. Alternatively or additionally, the network node device 200 may utilize other information about the location / movement of the network node device 200 and / or the client device 100. For example, if the network node device 200 corresponds to a satellite in the NTN, the network node device 200 may use the ephemeris of the network node device 200.

[0092] The network node device 200 may determine a transmission repetition number for an uplink transmission and transmit an indication of the transmission repetition number to the client device.

[0093] According to an example embodiment, the network node device 200 comprises a satellite of a non-terrestrial network.

[0094] Although the network node device 200 is depicted as including only one processor 201, the network node device 200 may include more processors. In one embodiment, the memory 202 is capable of storing instructions, such as an operating system and / or various applications. In addition, the memory 202 may include a storage device, which may be used, for example, to store at least some of the timing advance compensation function curves used in the disclosed embodiments.

[0095] In addition, the processor 201 is capable of executing the stored instructions. In one embodiment, the processor 201 can be implemented as a multi-core processor, a single-core processor, or a combination of one or more multi-core processors and one or more single-core processors. For example, the processor 201 can be implemented as one or more of various processing devices, such as a coprocessor, a microprocessor, a controller, a digital signal processor (DSP), a processing circuit system with or without an accompanying DSP, or various other processing devices, including integrated circuits, such as application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), microcontroller units (MCUs), hardware accelerators, special computer chips, etc. In one embodiment, the processor 201 can be configured to perform hard-coded functions. In one embodiment, the processor 201 is implemented as an executor of software instructions, wherein the instructions can specifically configure the processor 201 to perform the algorithms and / or operations described herein when the instructions are executed.

[0096] The memory 202 may be implemented as one or more volatile memory devices, one or more non-volatile memory devices, and / or a combination of one or more volatile memory devices and non-volatile memory devices. For example, the memory 202 may be implemented as a semiconductor memory (such as a mask ROM, a PROM (programmable ROM), an EPROM (erasable PROM), a flash ROM, a RAM (random access memory), etc.).

[0097] The network node device 200 may be a base station. The base station may include, for example, a fifth generation base station (gNB) or any device suitable for implementation in a satellite and providing an air interface for a client device to connect to a wireless network via wireless transmission.

[0098] Figure 3 A comparative example of the subject matter described herein is shown, illustrating a diagram of transmission repetition.

[0099] Narrowband IoT (NB-IoT) and enhanced Machine Type Communications (eMTC) are designed for low-power wide-area terrestrial networks, targeting long range (20dB better than GSM) and low device power consumption (up to 10 years of battery life). It may be desirable to implement long-range communications in NB-IoT and / or eMTC for applications such as non-terrestrial networks (NTNs).

[0100] Some example embodiments herein may relate to NB-IoT. However, any example embodiment may also be applied to eMTC.

[0101] One process used to achieve long-range transmission is the repetition of the coded payload to ensure sufficient energy is captured in the receiver. For example, the narrowband physical uplink shared channel (NPUSCH) can be repeated in N consecutive time slots. N can be defined as

[0102]

[0103] Where N rep is the number of repetitions, indicated in the scheduling downlink control information (DCI), N RU is the resource allocation field indicated in the scheduling DCI, and is the number of uplink time slots in the resource unit.

[0104] For example, the number of repetitions may be 1-128, and the number of resource units may be, for example, 1-10. For frame structure type 1 (FDD), the subcarrier spacing may be 3.75 kHz or 15 kHz, which corresponds to a slot length of 2 ms and 0.5 ms, respectively. Independent of the subcarrier spacing, the maximum number of uplink slots may be, for example, 16. Thus, the maximum transmission time may be

[0105] t 15kHz =0.5ms×128×10×16=10240ms

[0106] t 3.75kHz =2ms×128×10×16=40960ms

[0107] Such long transmission times can be challenging for NTN operations because certain radio parameters (such as TA) vary over time because low earth orbit (LEO) satellites move very quickly relative to the earth. For example, for a regenerative LEO at 600km altitude, the variation in round trip delay can be + / -20μs / s. Therefore, in a 10-40s transmission, the potential time shift can be 200-800μs, which can greatly exceed the cyclic prefix of about 5-8μs (which varies with subcarrier spacing and number of symbols).

[0108] The effect of long transmission times can be partially addressed by introducing transmission gaps. For example, a 40 ms gap may be inserted after a 256 ms NPUSCH transmission. In principle, this gap may allow the client device 100 to read the primary and secondary synchronization signals. However, the client device 100 may not be allowed to adjust its transmission timing during the repetition, nor should timing advance commands be applied. These gaps may also further increase the length of the transmission (by about 15%).

[0109] In NTN applications, since satellites may move relative to the earth at a speed of approximately 7.5 km / s, potential movement of the client device 100 over the earth may have limited impact on the drift of the TA compared to the movement of the satellites.

[0110] For the narrowband physical random access channel (NPRACH), the client device 100 may also apply repetition, but the resulting repetition time may be shorter, on the order of 700-2500ms. In addition, the cyclic prefix may be longer, and thus the impact of time shifts during repeated transmissions may not be an issue.

[0111] The example embodiments disclosed herein relate to uplink transmission timing of NB-IoT and / or eMTC devices. The example embodiments herein can solve some problems in non-terrestrial communications or other communication scenarios with large propagation delays and / or timing variations.

[0112] The client device 100 may perform an NPUSCH uplink transmission 301 with repetitions 302. The uplink transmission may be scheduled by the network node device 200 using a narrowband physical downlink control channel (NPDCCH). The network node device 200 may also schedule multiple TA commands using the NPDCCH. The client device 100 may use a transmission gap 305 between repetitions 302. Since the client device 100 applies the TA received prior to the uplink transmission 301, the timing drift 304 exceeds the cyclic prefix limit 303 after multiple transmission repetitions 302. Therefore, the transmission repetition 302 may not be time-consistent with the resources allocated for reception at the receiving end, thereby reducing the likelihood that the data is correctly decoded and increasing uplink interference in the receiver.

[0113] Figure 4 An example embodiment of the subject matter described herein is shown, which shows a diagram of transmission repetition with TA compensation.

[0114] The network node device 200 may provide multiple TA commands 401 to the client device 100. The network node device 200 may also provide a corresponding indication of a valid time 402 to the client device 100. The valid time 402 may indicate the time at which each TA command in the multiple TA commands 401 becomes valid. The network node device 200 may provide the TA command 401 and / or the valid time 402 before the start of an uplink transmission that is known to be repeated multiple times. This may replace the signaling of a single TA command before the start of the uplink transmission.

[0115] The network node device 200 may pre-calculate appropriate TA commands for a particular point in the near future. The network node device 200 may use, for example, the location of the client device 100 to calculate the TA command 401. For example, in an NTN, the network node device 200 may pre-calculate the TA command 401 using the predictability of satellite movement.

[0116] In addition, the network node device 200 may define the time when the uplink transmission of the client device 100 starts and the number of resource units used for transmission and / or the number of transmission repetitions. Therefore, the network node device 200 may determine at which time points an updated TA command is needed.

[0117] like Figure 4 As shown in the example embodiment of FIG. 1 , since the client device 100 applies a new TA command for each repetition 302, Figure 3 Compared to the comparative example, the TA drift 403 does not exceed the cyclic prefix limit 303 .

[0118] Figure 5 An example embodiment of the subject matter described herein is shown which shows a signaling diagram 500 .

[0119] The client device 100 may transmit a request 501 for uplink transmission to the network node device 200. The client device 100 may transmit the request 501 in response to payload data that needs to be transmitted.

[0120] After receiving the request 501 for uplink transmission, the network node device 200 may estimate 502 the location of the client device 100. The client device 100 may include, for example, a global navigation satellite system (GNSS) capability. Thus, the location of the client device 100 may be known to the network node device 200. Alternatively, the network node device 200 may already include information about the location of the client device 100.

[0121] The network node device 200 may calculate 503 a TA command and / or a corresponding valid time based on, for example, a relative position and / or relative movement of the client device 100 and the network node device 200 .

[0122] The network node device 200 may transmit a TA configuration message 504 to the client device 100. The TA configuration message 504 may include a plurality of TA commands and / or corresponding indications of validity times. The network node device 200 may also schedule uplink transmissions. The network node device 200 may, for example, transmit scheduling parameters to the client device 100. The scheduling parameters may include, for example, a start time for uplink transmissions, resources allocated for uplink transmissions, and / or a number of transmission repetitions to be used for uplink transmissions.

[0123] The client device 100 may use 505 a first TA command of the plurality of TA commands and initiate an uplink transmission 506. The client device 100 may also perform repetitions 507. There may be one or more transmission gaps 508 during the uplink transmission.

[0124] At a certain point in time, the client device 100 may use 509 a second TA command from among the plurality of TA commands. As described above, the validity period of the second TA command may have been indicated by the network node device 200 in the TA configuration message 504. The client device 100 may start using the second TA command in response to reaching the validity period of the second TA command.

[0125] The client device 100 may continue 510 uplink transmissions while using the second TA command. The client device 100 may also perform additional repetitions 507 while using the second TA command. There may also be additional transmission gaps 508 while the client device 100 is using the second TA command.

[0126] The client device 100 may continue uplink transmission until the data has been transferred.The client device 100 may use any number of the plurality of TA commands during the remaining transmission in a similar manner as disclosed above.

[0127] Figure 6 An example embodiment of the subject matter described herein is shown, which shows a flowchart 600. The network node device 200 may utilize the process presented in the flowchart 600 to determine a plurality of TA commands for the client device 100.

[0128] The network node device 200 may receive 601 a request for uplink transmission from the client device 100. The network node device 200 may perform 602 a scheduling process for the request. The network node device 200 may receive, for example, the number of bits to be transmitted and / or the current channel estimate in the request for uplink transmission. The network node device 200 may determine a modulation and coding scheme to be used for uplink transmission, a number of resource units to be used for uplink transmission, and / or a number of transmission repetitions to be used for uplink transmission. Based on these, the network node device 200 may determine an expected uplink transmission time without transmission gaps.

[0129] The network node apparatus 200 may further determine 603 the need for a transmission gap during the uplink transmission. For example, a transmission gap may be inserted after a preconfigured transmission length.

[0130] The network node device 200 may calculate 604 a timing drift during the uplink transmission. The timing drift may be due to, for example, satellite motion during the uplink transmission in the case of NTN. Alternatively or additionally, the timing drift may be due to other movement of the network node device 200 and / or the client device 100. The network node device 200 may calculate 604 the timing drift using, for example, satellite ephemeris and / or client device location.

[0131] The network node device 200 may calculate 605 the initial transmission time and save it to a time variable T. The network node device 200 may then compare 606 whether the time variable T is greater than the end time of the transmission. If the time variable T is greater than the end time of the transmission, the network node device 200 may transmit 607 scheduling information and a plurality of TA commands to the client device 100. Otherwise, the network node device 200 may continue to compare whether the timing drift at time T is greater than the cyclic prefix plus the margin. If the timing drift is not greater than the cyclic prefix plus the margin, the network node device 200 may increment 609 the time variable T forward in time and return to the comparison 606. If the timing drift is greater than the cyclic prefix plus the margin, the network node device 200 may continue to determine 610 the required TA command updates and / or corresponding valid times. The network node device 200 may add the TA command and / or time to the plurality of TA commands, continue to increment the time variable T forward in time, and return to the comparison 606.

[0132] The network node device 200 may continue the process until, for example, the time variable T is greater than the end time of the transmission. Therefore, when the process ends, the network node device 200 may have generated multiple TA commands and corresponding valid times.

[0133] The time variable T or any other amount of time (such as a number of valid times) may be based on, for example, a system frame number, a gap count, a repetition number, or a UTC time.

[0134] At least some example embodiments disclosed herein may enable the client device 100 to adjust the TA during long, repetitive uplink transmissions. This may require that the signal does not exceed the cyclic prefix and generate interference.

[0135] At least some example embodiments disclosed herein may enable the client device 100 to only need to receive multiple TA commands before a long uplink transmission.The client device 100 may receive multiple TA commands in, for example, a single message.

[0136] At least some of the example embodiments disclosed herein may avoid the need for the client device 100 to constantly switch between uplink and downlink (ie, between uplink transmission and reception during transmission gaps), thereby saving power.

[0137] At least some example embodiments disclosed herein may enable compensation for long propagation delays and potentially many downlink repetitions for receiving a TA command prior to the actual uplink. Each TA command in a plurality of TA commands may be associated with a corresponding validity time. Thus, if the actual timing advance command is received significantly later than the time it was originally sent, this may be compensated for.

[0138] Figure 7 An example embodiment of the subject matter described herein is shown, which shows a flow diagram of a method 700 .

[0139] According to an example embodiment, method 700 comprises receiving 701 a timing advance configuration message from a network node device, wherein the timing advance configuration message comprises a plurality of timing advance commands.

[0140] The method 700 may also include performing 702 a plurality of consecutive uplink transmissions to the network node device.

[0141] The method 700 may also include applying 703 a plurality of timing advance commands between a plurality of consecutive uplink transmissions.

[0142] Thus, method 700 may alternate between performing uplink transmissions and applying TA commands.

[0143] According to an example embodiment, the timing advance configuration message further includes an indication of validity times of the plurality of timing advance commands.The method 700 may further include applying the plurality of timing advance commands according to the indication of validity times.

[0144] The indication of the valid time may include at least one of: a plurality of valid times corresponding to a plurality of timing advance commands, or a period value indicating a time period for applying a new timing advance command among the plurality of timing advance commands.

[0145] The method 700 may further include, before receiving the timing advance configuration message, transmitting a request for uplink transmission to the network node device.

[0146] According to an example embodiment, the plurality of consecutive uplink transmissions corresponds to a transmission repetition.

[0147] According to an example embodiment, uplink transmissions are performed using a narrowband physical uplink shared channel.

[0148] According to an example embodiment, the timing advance configuration message is received using a narrowband physical downlink control channel.

[0149] According to an example embodiment, the method is performed by a client device, wherein the client device and the network node device are part of a non-terrestrial network.

[0150] According to an example embodiment, the method 700 is performed by an Internet of Things device or an enhanced machine type communication device.

[0151] The method 700 may be performed by, for example, the client device 100 .

[0152] Figure 8 An example embodiment of the subject matter described herein is shown, which shows a flow diagram of a method 800 .

[0153] According to an example embodiment, method 800 includes estimating 801 a timing drift of a client device.

[0154] The method 800 may also include determining 802 a plurality of timing advance commands for the client device based on the estimated timing drift.

[0155] The method 800 may further include transmitting 803 a timing advance configuration message including a plurality of timing advance commands to a client device.

[0156] The method 800 may further include determining an indication of a validity time based on the estimated timing drift, wherein the indication of the validity time corresponds to the plurality of timing advance commands.The timing advance configuration message may further include an indication of the validity time.

[0157] According to an exemplary embodiment, the indication of the validity time includes at least one of: a plurality of validity times corresponding to a plurality of timing advance commands, or a period value indicating a time period for applying a new timing advance command among the plurality of timing advance commands.

[0158] According to an example embodiment, determining a plurality of timing advance commands and / or an indication of validity times for a client device is performed in response to receiving a request for an uplink transmission from a client device.

[0159] According to an example embodiment, the method 800 further includes determining scheduling parameters for the client device, determining an expected uplink transmission time based on the scheduling parameters, and determining an indication of a plurality of timing advance commands and / or validity times based on the expected uplink transmission time.

[0160] According to an example embodiment, multiple timing advance commands and indications of valid times are determined based at least on the relative position of the network node device and / or satellites corresponding to the network node device and the client device, and / or the relative movement of the network node device and / or satellites corresponding to the network node device and the client device.

[0161] According to an example embodiment, the timing advance configuration message is transmitted using a narrowband physical downlink control channel.

[0162] The method 800 may also include determining a transmission repetition number for the uplink transmission and transmitting an indication of the transmission repetition number to the client device.

[0163] The method 800 may be performed by, for example, the network node device 200. The network node device 200 may be a part of the NTN.

[0164] The functions described herein may be performed at least in part by one or more computer program product components (such as software components). According to one embodiment, the client device 100 and / or the network node device 200 includes a processor configured by a program code, which performs the described operations and embodiments of the functions when executed. Alternatively or additionally, the functions described herein may be performed at least in part by one or more hardware logic components. For example, and not limitation, illustrative types of hardware logic components that can be used include field programmable gate arrays (FPGAs), program-specific integrated circuits (ASICs), program-specific standard products (ASSPs), system-on-chip systems (SOCs), complex programmable logic devices (CPLDs), and graphics processing units (GPUs).

[0165] Any range or device value given herein may be expanded or altered without losing the effect sought. In addition, any embodiment may be combined with another embodiment unless expressly prohibited.

[0166] Although the subject matter has been described in language specific to structural features and / or acts, it should be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Instead, the specific features and acts described above are disclosed as examples of implementing the claims, and other equivalent features and acts are intended to fall within the scope of the claims.

[0167] It should be understood that the benefits and advantages described above may relate to one embodiment or may relate to several embodiments. The embodiments are not limited to embodiments that solve any or all of the problems described, nor are they limited to embodiments that have any or all of the benefits and advantages described. It will be further understood that reference to "an" item may refer to one or more of these items.

[0168] Where appropriate, the steps of the methods described herein may be performed in any suitable order or simultaneously. In addition, individual blocks may be deleted from any method without departing from the spirit and scope of the subject matter described herein. Aspects of any embodiment described above may be combined with aspects of any other embodiment described to form additional embodiments without losing the effects sought.

[0169] The term "comprising" is used herein to mean including the identified methods, blocks or elements, but these blocks or elements do not comprise an exclusive list and the method or apparatus may contain additional blocks or elements.

[0170] It should be understood that the above description is given as an example only, and various modifications may be made by those skilled in the art. The above description, examples and data provide a complete description of the structure and use of the exemplary embodiments. Although various embodiments have been described above with a certain degree of specificity or with reference to one or more individual embodiments, those skilled in the art may make various changes to the disclosed embodiments without departing from the spirit or scope of this specification.

Claims

1. A client device, include: at least one processor; as well as at least one memory including computer program code; The at least one memory and the computer program code are configured to, with the at least one processor, cause the client device to: receiving a timing advance configuration message from a network node device of a non-terrestrial network, wherein the timing advance configuration message includes a plurality of timing advance commands; performing a plurality of consecutive uplink transmissions to the network node device; as well as Applying the multiple timing advance commands between the multiple consecutive uplink transmissions, wherein the applying comprises at least transmitting a first set of one or more uplink transmissions using a first timing advance, and continuously transmitting a second set of one or more uplink transmissions using a second timing advance in the time domain, wherein the first timing advance and the second timing advance are based on the multiple timing advance commands.

2. The client device of claim 1 , wherein the timing advance configuration message further comprises an indication of a validity time of the plurality of timing advance commands, and wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the client device to: Based on the indication of the validity time, the plurality of timing advance commands are applied.

3. The client device of claim 2, wherein the indication of the validity time comprises at least one of: a plurality of valid times corresponding to the plurality of timing advance commands; or A period value indicating a time period for applying a new timing advance command among the multiple timing advance commands.

4. The client device of any preceding claim, wherein the at least one memory and the computer program code are further configured to, together with the at least one processor, cause the client device to: Before receiving the timing advance configuration message, a request for the uplink transmission is transmitted to the network node device.

5. The client device of any one of claims 1 to 3, wherein the plurality of consecutive uplink transmissions corresponds to transmission repetitions.

6. The client device of claim 5, wherein the at least one memory and the computer program code are further configured to, together with the at least one processor, cause the client device to: The number of transmission repetitions to be performed in the plurality of consecutive uplinks is received from the network node device.

7. A client device according to claim 5, wherein the multiple consecutive uplink transmissions correspond to transmission repetitions, so that a first set of the one or more uplink transmissions includes a plurality of repeated uplink transmissions, and a second set of the one or more uplink transmissions includes a plurality of repeated uplink transmissions.

8. The client device according to any one of claims 1 to 3, wherein the at least one memory and the computer program code are further configured to, together with the at least one processor, cause the client device to: The uplink transmission is performed using a narrowband physical uplink shared channel.

9. The client device according to any one of claims 1 to 3, wherein the at least one memory and the computer program code are further configured, together with the at least one processor, to cause the client device to: Receive the timing advance configuration message using a narrowband physical downlink control channel.

10. The client device according to any one of claims 1 to 3, wherein the client device and the network node device are part of the non-terrestrial network.

11. A network node device of a non-terrestrial network, comprising: At least one processor; and At least one memory, including computer program code; The at least one memory and the computer program code are configured, together with the at least one processor, to cause the network node device to: Estimate the timing drift of the client device; Based on the estimated timing drift, determine a plurality of timing advance commands for the client device; Transmit a timing advance configuration message including the plurality of timing advance commands to the client device, wherein the plurality of timing advance commands are configured to be applied by the client device between a plurality of consecutive uplink transmissions; and Receive the plurality of consecutive uplink transmissions from the client device, wherein receiving the plurality of consecutive uplink transmissions includes at least receiving a first set of one or more uplink transmissions transmitted by the client device using a first timing advance, and continuously receiving in the time domain a second set of one or more uplink transmissions transmitted by the client device using a second timing advance, wherein the first timing advance and the second timing advance are based on the plurality of timing advance commands.

12. The network node device according to claim 11, wherein the at least one memory and the computer program code are further configured, together with the at least one processor, to cause the network node device to: Based on the estimated timing drift, determine an indication of the valid time, wherein the indication of the valid time corresponds to the plurality of timing advance commands, and wherein the timing advance configuration message further includes the indication of the valid time.

13. The network node device according to claim 12, wherein the indication of the valid time includes at least one of the following: A plurality of valid times corresponding to the plurality of timing advance commands; or A period value indicating the time period for applying a new timing advance command among the plurality of timing advance commands.

14. The network node device according to any one of claims 11 to 13, wherein the at least one memory and the computer program code are further configured, together with the at least one processor, to cause the network node device to: In response to receiving a request for an uplink transmission from the client device, determine the plurality of timing advance commands for the client device and / or the indication of the valid time.

15. The network node device according to any one of claims 11 to 13, wherein the at least one memory and the computer program code are further configured, together with the at least one processor, to cause the network node device to: determining scheduling parameters for the client device; Based on the scheduling parameters, determining an expected uplink transmission time; and The plurality of timing advance commands and / or the indication of the validity time are determined based on the expected uplink transmission time.

16. The network node device according to any one of claims 11 to 13, wherein the at least one memory and the computer program code are further configured to, together with the at least one processor, cause the network node device to: The multiple timing advance commands and the indication of the effective time are determined based at least on the relative position of the network node device and / or the satellite corresponding to the network node device and the client device, and / or the relative movement of the network node device and / or the satellite corresponding to the network node device and the client device.

17. The network node device according to any one of claims 11 to 13, wherein the at least one memory and the computer program code are further configured to, together with the at least one processor, cause the network node device to: The timing advance configuration message is transmitted using a narrowband physical downlink control channel.

18. The network node device according to any one of claims 11 to 13, wherein the at least one memory and the computer program code are further configured to, together with the at least one processor, cause the network node device to: determining a number of transmission repetitions for the uplink transmission; and An indication of the number of transmission repetitions is transmitted to the client device.

19. The network node device according to any one of claims 11 to 13, wherein the network node device is part of a non-terrestrial network.

20. A method of communication, include: receiving a timing advance configuration message from a network node device of a non-terrestrial network, wherein the timing advance configuration message includes a plurality of timing advance commands; performing a plurality of consecutive uplink transmissions to the network node device; as well as Applying the multiple timing advance commands between the multiple consecutive uplink transmissions, wherein the applying comprises at least transmitting a first set of one or more uplink transmissions using a first timing advance, and continuously transmitting a second set of one or more uplink transmissions using a second timing advance in the time domain, wherein the first timing advance and the second timing advance are based on the multiple timing advance commands.

21. The method of claim 20, wherein the timing advance configuration message further comprises an indication of the validity time of the plurality of timing advance commands, and wherein the method further include: Based on the indication of the validity time, the plurality of timing advance commands are applied.

22. The method of claim 21, wherein the indication of the validity time comprises at least one of: a plurality of valid times corresponding to the plurality of timing advance commands; or A period value indicating a time period for applying a new timing advance command among the multiple timing advance commands.

23. The method according to any one of claims 20 to 22, wherein the method further comprises include: Before receiving the timing advance configuration message, a request for the uplink transmission is transmitted to the network node device.

24. The method according to any one of claims 20 to 22, wherein the plurality of consecutive uplink transmissions corresponds to transmission repetitions.

25. The method according to claim 24, wherein the method further comprises include: The number of transmission repetitions to be performed in the plurality of consecutive uplinks is received from the network node device.

26. The method of claim 24, wherein the plurality of consecutive uplink transmissions correspond to transmission repetitions such that a first set of the one or more uplink transmissions comprises a plurality of repeated uplink transmissions and a second set of the one or more uplink transmissions comprises a plurality of repeated uplink transmissions.

27. The method according to any one of claims 20 to 22, wherein the method further comprises include: The uplink transmission is performed using a narrowband physical uplink shared channel.

28. The method according to any one of claims 20 to 22, wherein the method further comprises include: The timing advance configuration message is received using a narrowband physical downlink control channel.

29. A method according to any one of claims 20 to 22, wherein the method is performed by a client device, and wherein the client device and the network node device are part of a non-terrestrial network.

30. A computer program product comprising a program code, the program code being configured to perform the method according to any one of claims 20 to 29 when the computer program product is executed on a computer.

31. A method of communication performed by a network node device of a non-terrestrial network, include: estimating the timing drift of client devices; determining a plurality of timing advance commands for the client device based on the estimated timing drift; transmitting a timing advance configuration message including the plurality of timing advance commands to the client device, wherein the plurality of timing advance commands are configured to be applied by the client device between a plurality of consecutive uplink transmissions; as well as The plurality of consecutive uplink transmissions are received from the client device, wherein receiving the plurality of consecutive uplink transmissions comprises at least receiving a first set of one or more uplink transmissions transmitted by the client device using a first timing advance, and continuously receiving in a time domain a second set of one or more uplink transmissions transmitted by the client device using a second timing advance, wherein the first timing advance and the second timing advance are based on the plurality of timing advance commands.

32. The method according to claim 31, wherein the method further comprises include: Based on the estimated timing drift, an indication of a validity time is determined, wherein the indication of a validity time corresponds to the plurality of timing advance commands, and wherein the timing advance configuration message further comprises the indication of a validity time.

33. The method of claim 32, wherein the indication of the validity time comprises at least one of: a plurality of valid times corresponding to the plurality of timing advance commands; or A period value indicating a time period for applying a new timing advance command among the plurality of timing advance commands.

34. The method according to any one of claims 31 to 33, wherein the method further comprises include: In response to receiving a request for uplink transmission from the client device, the plurality of timing advance commands and / or the indication of validity time for the client device are determined.

35. The method according to any one of claims 31 to 33, wherein the method further comprises include: determining scheduling parameters for the client device; determining an expected uplink transmission time based on the scheduling parameters; as well as The plurality of timing advance commands and / or the indication of the validity time are determined based on the expected uplink transmission time.

36. The method according to any one of claims 31 to 33, wherein the method further comprises include: The multiple timing advance commands and the indication of the effective time are determined based at least on the relative position of the network node device and / or the satellite corresponding to the network node device and the client device, and / or the relative movement of the network node device and / or the satellite corresponding to the network node device and the client device.

37. The method according to any one of claims 31 to 33, wherein the method further comprises include: The timing advance configuration message is transmitted using a narrowband physical downlink control channel.

38. The method according to any one of claims 31 to 33, wherein the method further comprises include: determining a number of transmission repetitions for the uplink transmission; as well as An indication of the number of transmission repetitions is transmitted to the client device.

39. A method according to any one of claims 31 to 33, wherein the network node device is part of the non-terrestrial network.

40. A computer program product comprising a program code, the program code being configured to perform the method according to any one of claims 31 to 39 when the computer program product is executed on a computer.

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