System and method for uplink backoff interval

Abstract

A method for enhancing an uplink backoff interval is disclosed herein. In one embodiment, the method is configured to: insert a time interval between a first transmission and a second transmission by a wireless communication device according to a configuration from a wireless communication node, wherein the first transmission includes the wireless communication device sending a plurality of first uplink messages to the wireless communication node, and the second transmission includes the wireless communication device sending a plurality of second uplink messages to the wireless communication node.

Description

Technical Field

[0001] The present disclosure relates generally to wireless communications and, more particularly, to systems and methods for enhancing uplink backoff intervals. Background Art

[0002] A crystal oscillator may be used to generate a frequency, clock signal in a user equipment ("UE"). If the UE is a low-cost UE, the crystal oscillator frequency error may be very large. An example of a frequency error may be 1 ppm. The crystal oscillator frequency error may also be caused by temperature variations or aging components.

[0003] Even after the devices are synchronized, there may still be a frequency error due to the precision of the crystal oscillator. The remaining frequency error after the synchronization period may be referred to as the initial frequency offset. Over time, the frequency offset may increase to a value that is unacceptable for system performance. In some embodiments, the maximum frequency error may not exceed 0.15 ppm. In other embodiments, the maximum frequency error may not exceed 0.25 ppm. In other embodiments, the maximum frequency error may not exceed 0.45 ppm.

[0004] Different networks can have different degrees of frequency error. For example, for IoT user equipment devices, non-terrestrial networks (“NTNs”) inherently have longer round-trip times and longer uplink transmission signals, which can cause frequency errors to increase over time, which can severely degrade communication performance. Summary of the invention

[0005] The example embodiments disclosed herein are intended to solve problems associated with one or more of the problems presented in the prior art, as well as to provide additional features that will become apparent by reference to the following detailed description when taken in conjunction with the accompanying drawings. According to various embodiments, example systems, methods, devices, and computer program products are disclosed herein. However, it should be understood that these embodiments are presented by way of example, not limitation, and it will be apparent to a person of ordinary skill in the art who reads this disclosure that various modifications may be made to the disclosed embodiments while remaining within the scope of this disclosure.

[0006] In one embodiment, a method performed by a wireless communication device includes: the wireless communication device inserting a time interval between a first transmission and a second transmission according to a configuration from a wireless communication node, wherein the first transmission includes the wireless communication device sending a plurality of first uplink messages to the wireless communication node, and the second transmission includes the wireless communication device sending a plurality of second uplink messages to the wireless communication node.

[0007] In another embodiment, a method performed by a wireless communication node includes: determining, by the wireless communication node, a time interval to be inserted between a first transmission and a second transmission based on a navigation signal, wherein the first transmission includes the wireless communication device sending a plurality of first uplink messages to the wireless communication node, and the second transmission includes the wireless communication device sending a plurality of second uplink messages to the wireless communication node.

[0008] The above and other aspects and embodiments thereof will be described in more detail in the drawings, the description and the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Various example embodiments of the present solution are described in detail below with reference to the following diagrams or drawings. The drawings are provided for illustrative purposes only and only depict example embodiments of the present solution to facilitate the reader's understanding of the present solution. Therefore, the drawings should not be considered as limiting the breadth, scope or applicability of the present solution. It should be noted that for clarity and ease of illustration, these drawings are not necessarily drawn to scale.

[0010] Figure 1 An example cellular communication network according to an embodiment of the present disclosure is shown, in which the techniques and other aspects disclosed herein may be implemented.

[0011] Figure 2 A block diagram of an example base station and user equipment terminal according to some embodiments of the present disclosure is shown.

[0012] Figure 3 A block diagram of an example non-terrestrial communication network is shown.

[0013] Figure 4 A block diagram of an example non-terrestrial communication network is shown.

[0014] Figure 5 A diagram showing a real clock compared to an ideal clock.

[0015] Figure 6 A flow chart illustrating an example method in which a UE inserts UL gaps to correct frequency error.

[0016] Figure 7 A flow chart illustrating an example method by which a wireless node configures time intervals to be inserted into UL intervals.

[0017] Figure 8 A diagram illustrating an UL interval between two consecutive transmissions sent by a UE, wherein the UE performs frequency error compensation during the UL interval, according to some embodiments of the present disclosure. DETAILED DESCRIPTION

[0018] Various example embodiments of the present solution are described below with reference to the accompanying drawings to enable a person of ordinary skill in the art to make and use the present solution. It is apparent to a person of ordinary skill in the art that, after reading this disclosure, various changes or modifications may be made to the examples described herein without departing from the scope of the present solution. Therefore, the present solution is not limited to the example embodiments and applications described and illustrated herein. In addition, the specific order or hierarchy of steps in the methods disclosed herein are merely example methods. Based on design preferences, the specific order or hierarchy of steps of the disclosed methods or processes may be rearranged while remaining within the scope of the present solution. Therefore, a person of ordinary skill in the art should understand that the methods and techniques disclosed herein present various steps or behaviors in a sample order, and unless otherwise expressly stated, the present solution is not limited to the specific order or hierarchy presented.

[0019] Figure 1 An example wireless communication network and / or system 100 is shown according to an embodiment of the present disclosure, in which the techniques disclosed herein may be implemented in the cellular communication network. In the following discussion, the wireless communication network 100 may be any wireless network such as a cellular network or a narrowband Internet of Things (NB-IoT) network, and is referred to herein as "network 100". Such an example network 100 includes a base station 102 (hereinafter referred to as "BS 102") and a user equipment device 104 (hereinafter referred to as "UE 104"), which may communicate with each other via a communication link 110 (e.g., a wireless communication channel), and cell clusters 126, 130, 132, 134, 136, 138, and 140 covering a geographic area 101. In Figure 1 1, BS 102 and UE 104 are contained within the respective geographic boundaries of cell 126. Each of the other cells 130, 132, 134, 136, 138, and 140 may include at least one base station operating over its allocated bandwidth to provide adequate wireless coverage to its intended users.

[0020] For example, BS 102 may operate on the allocated channel transmission bandwidth to provide sufficient coverage to UE 104. BS 102 and UE 104 may communicate via downlink radio frames 118 and uplink radio frames 124, respectively. Each radio frame 118 / 124 may be further divided into subframes 120 / 127, which may include data symbols 122 / 128. In the present disclosure, BS 102 and UE 104 are described herein as non-limiting examples of "communication nodes", which may generally practice the methods disclosed herein. According to various embodiments of the present solution, such communication nodes may be capable of wireless and / or wired communication.

[0021] Figure 2 A block diagram of an exemplary wireless communication system 200 for transmitting and receiving wireless communication signals (e.g., OFDM / OFDMA signals) according to some embodiments of the present solution is shown. The system 200 may include components and elements configured to support known or conventional operating features that need not be described in detail herein. In one illustrative embodiment, as described above, the system 200 may be used in applications such as Figure 1 The wireless communication environment 100 may be used to transmit (eg, send and receive) data symbols.

[0022] The system 200 generally includes a base station 202 (hereinafter referred to as "BS 202") and a user equipment terminal 204 (hereinafter referred to as "UE 204"). The BS 202 includes a BS (base station) transceiver module 210, a BS antenna 212, a BS processor module 214, a BS memory module 216, and a network communication module 218, each of which is coupled and interconnected to each other via a data communication bus 220 as needed. The UE 204 includes a UE (user equipment) transceiver module 230, a UE antenna 232, a UE memory module 234, and a UE processor module 236, each of which is coupled and interconnected to each other via a data communication bus 240 as needed. The BS 202 communicates with the UE 204 via a communication channel 250, which can be any wireless channel or other medium suitable for transmitting data as described herein.

[0023] As will be appreciated by those skilled in the art, the system 200 may also include Figure 2 Any number of modules other than the modules shown. It will be appreciated by those skilled in the art that the various illustrative blocks, modules, circuits, and processing logic described in conjunction with the embodiments disclosed herein can be implemented in hardware, computer-readable software, firmware, or any actual combination thereof. In order to clearly illustrate this interchangeability and compatibility of hardware, firmware, and software, various illustrative components, blocks, modules, circuits, and steps are generally described according to their functions. Whether this function is implemented as hardware, firmware, or software depends on the specific application and the design constraints imposed on the entire system. People familiar with the concepts described herein can implement this function in an appropriate manner for each specific application, but the decision of this embodiment should not be interpreted as limiting the scope of the present disclosure.

[0024] According to some embodiments, the UE transceiver 230 may be referred to herein as an "uplink" transceiver 230, which includes a radio frequency (RF) transmitter and an RF receiver, each of which includes circuitry coupled to an antenna 232. A duplex switch (not shown) may alternatively couple the uplink transmitter or receiver to the uplink antenna in a time duplex manner. Similarly, according to some embodiments, the BS transceiver 210 may be referred to herein as a "downlink" transceiver 210, which includes an RF transmitter and an RF receiver, each of which includes circuitry coupled to a downlink antenna 212. The downlink duplex switch may alternatively couple the downlink transmitter or receiver to the downlink antenna 212 in a time duplex manner. The operation of the two transceiver modules 210 and 230 may be coordinated in time such that the uplink receiver circuit is coupled to the uplink antenna 232 while the downlink transmitter is coupled to the downlink antenna 212 to receive transmissions over the wireless transmission link 250. In some embodiments, there is tight time synchronization with minimum guard times between changes in duplex direction.

[0025] The UE transceiver 230 and the base station transceiver 210 are configured to communicate via a wireless data communication link 250 and cooperate with an appropriately configured RF antenna arrangement 212 / 232 capable of supporting a specific wireless communication protocol and modulation scheme. In some illustrative embodiments, the UE transceiver 210 and the base station transceiver 210 are configured to support industry standards such as Long Term Evolution (LTE) and emerging 5G standards. However, it should be understood that the present disclosure is not necessarily limited to the application of specific standards and related protocols. Instead, the UE transceiver 230 and the base station transceiver 210 can be configured to support alternative or additional wireless data communication protocols, including future standards or variants thereof.

[0026] According to various embodiments, BS202 may be, for example, an evolved Node B (eNB), a serving eNB, a target eNB, a femtocell or a microcell. In some embodiments, UE 204 may be embodied in various types of user equipment such as mobile phones, smart phones, personal digital assistants (PDAs), tablet computers, laptop computers, wearable computing devices, and the like. Processor modules 214 and 236 may be implemented or implemented with a general purpose processor, a content addressable memory, a digital signal processor, an application specific integrated circuit, a field programmable gate array, any suitable programmable logic device, a discrete gate or transistor logic, a discrete hardware component, or any combination thereof designed to perform the functions described herein. In this way, the processor may be implemented as a microprocessor, a controller, a microcontroller, a state machine, and the like. The processor may also be implemented as a combination of computing devices, such as a combination of a digital signal processor and a microprocessor, a plurality of microprocessors, one or more microprocessors combined with a digital signal processor core, or any other such configuration.

[0027] In addition, the steps of the methods or algorithms described in conjunction with the embodiments disclosed herein may be directly embodied in hardware, firmware, software modules executed by the processor modules 214 and 236, respectively, or in any practical combination thereof. The memory modules 216 and 234 may be implemented as RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art. In this regard, the memory modules 216 and 234 may be coupled to the processor modules 214 and 236, respectively, so that the processor modules 214 and 236 can read information from the memory modules 216 and 234, respectively, and write information to the memory modules 216 and 234. The memory modules 216 and 234 may also be integrated into their respective processor modules 214 and 236. In some embodiments, the memory modules 216 and 234 may each include a cache for storing temporary variables or other intermediate information during the execution of instructions to be executed by the processor modules 214 and 236, respectively. The memory modules 216 and 234 may also each include non-volatile memory for storing instructions to be executed by the processor modules 214 and 236, respectively.

[0028] The network communication module 218 generally represents the hardware, software, firmware, processing logic and / or other components of the base station 202, which enables bidirectional communication between the base station transceiver 210 and other network components and communication nodes configured to communicate with the base station 202. For example, the network communication module 218 can be configured to support Internet or WiMAX traffic. In a typical deployment, but not limited to this, the network communication module 218 provides an 802.3 Ethernet interface so that the base station transceiver 210 can communicate with a traditional Ethernet-based computer network. In this way, the network communication module 218 can include a physical interface for connecting to a computer network (e.g., a mobile switching center (MSC)). The terms "configured for", "configured to" and their conjunctions as used herein with respect to a specified operation or function refer to a device, component, circuit, structure, machine, signal, etc., which is physically constructed, programmed, formatted and / or arranged to perform a specified operation or function.

[0029] When devices communicate via half-duplex frequency division duplex ("HD FDD"), the devices may not transmit and receive at the same time. Examples of these devices may include low-cost narrowband devices connected to the Internet, in other words, narrowband Internet of Things devices ("NB-IoT"). In areas where terrestrial network services are weak or unavailable, NTN networks may be employed to support the connection of large-scale IOT devices. NTNs such as geostationary orbit ("GEO") satellites can provide local or regional services across continents. However, special care must be taken when using NTN networks.

[0030] The rapid movement of the satellite can cause Doppler shifts. In addition, the distance between the satellite and the ground wireless communication device can result in a large round-trip time for the transmission.

[0031] The transmissions to the GEO satellites can be very long due to the need for multiple repetitions. If the UE is communicating using NTN, for example, when there is weak or no terrestrial network service, frequency errors above a certain threshold may severely degrade communication performance.

[0032] Figure 3 A block diagram of an example non-terrestrial communication network 300 including at least one wireless communication node based on an unmanned aerial system is shown. In particular, Figure 3 A communication network 300 is shown, which includes a satellite or unmanned aerial vehicle (UAV) 302, a UE 304, a gateway 306, and a data network 308. The satellite 302 can be used as a platform for a base station, such as, for example, the above-mentioned Figure 1 and 2 The BSs 102 and 202 discussed above, while the UE 304 may be similar to the above with respect to Figure 1 and 2UE 104 and 204 are discussed. UE 304 and the BS on satellite 302 can communicate via communication link 310, and the BS on satellite 302 and gateway 306 can communicate via feeder link 312. Gateway 306 can communicate with data network 308 via data link 314.

[0033] Figure 4 Another example non-terrestrial communication network 400 including at least one UAV system-based wireless communication node is shown. Figure 4 The communication network 400 shown is similar to Figure 3 The communication network 300 is shown, but includes the addition of a satellite or UAV platform 402 . Figure 4 A scenario is depicted where a communication network includes a satellite constellation allowing communication between a UE and a gateway or data network.

[0034] The gateway may be one of several gateways capable of providing connectivity between the satellite 302 / 402 and the data network 308, which may be a public terrestrial data network. The gateway may be deployed in a target coverage area of ​​the satellite, which may include a regional or continental coverage area. In an example where the satellite is a non-geostationary orbit satellite ("non-GEO satellite"), the satellite may be continuously served by one or more gateways at a time. The communication network may ensure that continuity of service links and feeder links is maintained between successive gateways, with sufficient duration for mobility anchoring and handover. In some examples, a UE in a cell may be served by only one gateway.

[0035] Satellites can implement transparent or regenerative (on-board processing) payloads. A satellite can generate multiple beams through a service area limited by its field of view, depending on the onboard antenna characteristics and the satellite's minimum elevation angle. The footprint of the beam on the Earth's surface can be elliptical. In instances where a satellite implements a transparent payload, the satellite can perform wireless filtering, frequency conversion, and amplification to repeat the signal. In instances where a satellite platform implements a regenerative payload, the satellite can perform RF filtering, frequency conversion, amplification, as well as demodulation / modulation, switching and / or routing, coding / modulation, etc., effectively performing at least some of the functions of a base station on the satellite.

[0036] In instances where the communication system includes a satellite constellation, for example, Figure 4 The communication system shown, the network may include an inter-satellite link (ISL) 412. In some such instances, the satellite may implement a regenerative payload. The ISL may operate in the RF or optical frequency bands.

[0037] Table 1 below lists the Figure 3 and Figure 4The various types of satellites shown in Table 1 are for reference only. The satellite types and corresponding information shown in Table 1 are for example only and are not limiting, as other types of platforms and satellites may also be utilized.

[0038] Table 1

[0039]

[0040]

[0041] In some embodiments, GEO satellites and UAS platforms can be used to provide continental, regional or local services. In some embodiments, constellations of LEO and MEO satellites can be used to provide services in the northern and southern hemispheres. In some instances, satellite constellations can even provide global coverage including polar regions. In some such instances, appropriate orbital inclination, ISL and beams can be selected.

[0042] Figure 5 is an example diagram comparing an ideal clock to a real clock. At 501, an error of 6Δ is observed. This error indicates that some devices (such as NB-IoT devices) will have a frequency error caused by a real crystal oscillator rather than an ideal crystal oscillator.

[0043] As described above, a crystal oscillator frequency error exceeding an error threshold in an NTN may severely degrade performance. Therefore, an enhanced uplink ("UL") compensation interval design can address the issue of UE crystal oscillator frequency error in NTN network deployments. The error caused by an imperfect crystal oscillator can be addressed by the implementation of the UL compensation interval.

[0044] Figure 6 A flowchart of an example method of a UE inserting an UL interval to correct a frequency error is shown. As described in 601, the UE may insert an UL time interval between a first transmission and a second transmission. To correct the frequency error, the behavior of the UE during the UL interval varies according to the capabilities of the UE.

[0045] Figure 7 A flow chart illustrating an example method for a wireless node to configure a time interval to be inserted into an UL interval. As discussed further below, the time interval may be used to correct a frequency error between a UE device and a wireless node in an NTN network.

[0046] Figure 8 is a diagram of a UL interval between two consecutive transmissions sent by a UE, wherein the UE performs frequency error compensation during the UL interval according to some embodiments of the present disclosure.

[0047] To compensate for frequency offset, the UE may insert an UL interval between UL transmissions. The UL interval may be determined by a node. In some embodiments, a node (e.g., a base station) may determine the UL interval based on a navigation signal. At the end of the maximum continuous UL transmission, the UE may insert an UL interval after the first UL transmission. The time interval may separate the UL message in the first transmission from the UL message in the second transmission.

[0048] In some embodiments, the duration of the first transmission may be determined by monitoring a frequency offset and evaluating whether the frequency offset meets a threshold. In an alternative embodiment, the duration of the first transmission may be determined by monitoring a timing offset and evaluating whether the timing offset meets a threshold.

[0049] In some embodiments, the threshold is a fixed value. Thus, the duration of the first transmission is a fixed value. In other embodiments, the threshold may be determined based on an evaluation. The frequency offset may be evaluated by an analysis of the frequency drift rate or other predictor models that may be used to calculate the frequency offset.

[0050] At 801, a UE is shown sending a UL signal of length x subframes. The transmissions to the satellite are long because they are repeated.

[0051] In addition, UL transmissions are sparse and unpredictable. At the end of the UL transmission of x subframes, a gap is inserted before the next UL transmission of x subframes begins. The UL gap is shown by 802. In some embodiments, the gap is inserted immediately after the first transmission. The length of the time interval can be one or more symbols, one or more time slots, one or more subframes, one or more milliseconds, or one or more navigation signal cycles.

[0052] In some embodiments, the UL interval may be determined based on a frequency offset and at least one or more DL resources and one or more GNSS resources. In some embodiments, the UL interval may be based on a subcarrier spacing of at least one of the first transmission or the second transmission. In some embodiments, the UL interval is a fixed length and may include various situations: a time offset between a time when the UE transmits a physical random access channel ("PRACH") and a time when the UE transmits a physical uplink shared channel ("PUSCH"), the time offset between the PRACH and the corresponding PUSCH may be included in the UL interval; a time offset between a time when the UE transmits the PRACH in one UL transmission and a time when the UE transmits the PRACH in another UL transmission; a time offset between a time when the UE transmits a first message in one UL transmission and a time offset between a PRACH and a PUSCH in another UL transmission by the UE, wherein the first message contains the PRACH, the PUSCH, and the time offset between the PRACH and the PUSCH; a time offset between a time when the UE transmits the PUSCH in one UL transmission and a time when the UE transmits the PUSCH in another UL transmission by the UE. When the UL interval is defined to include these time offsets, the behavior of the UE is constrained so that the UE compensates for the frequency error during the UL interval. Thus, each of the first transmission and the second transmission may include at least one of a PUSCH or a PRACH.

[0053] The UL time interval length may determine the available downlink ("DL") resources such as narrowband reference signals ("NRS") and synchronization signals. For example, the UE may estimate and measure what DL resources it needs. Therefore, a larger backoff interval may mean that the UE estimates that it needs more resources than it actually needs for the transmission. Therefore, it is advantageous to fine-tune the backoff interval as much as possible.

[0054] Depending on the capability type of the UE, the behavior of the UE may be different with respect to what to do during the UL interval. During the UL interval, the UE may receive a navigation signal or at least one of a plurality of DL messages. The received DL message may be sent from a wireless access node. In an NTN system, the navigation signal may be sent by a satellite. In some embodiments, the navigation signal may be a non-terrestrial network signal.

[0055] During the UL interval, the UE uses the received resources to determine a value for correcting the frequency error. The value may be a timing adjustment value or a frequency adjustment value. The value is applied during the second transmission, which adjusts the timing or frequency of the UE.

[0056] As described above, the wireless node may configure the UL interval. The wireless node may send configuration information to the UE prior to the first transmission of the UE. The wireless node may determine the UL interval configuration based on the capabilities of the UE and the capability information reported by the UE. For example, if the UE has an NTN module (e.g., a GNSS module), the wireless node may determine to configure the UL interval so that the UE can use signals from satellites and received by the GNSS module to correct frequency errors, as discussed further below.

[0057] In some embodiments, the UL interval configuration may be indicated to the UE via high-layer signaling. For example, a wireless node or a base station may insert the UL interval configuration information into a radio resource control ("RRC") message and a media access control ("MAC") control element. In other words, high-layer signaling refers to a message transmitted by a control terminal in the MAC layer. The configuration information of the UL interval may include at least one of the time domain length of the time interval and the period of the time interval.

[0058] In other embodiments, there may be a default UL configuration such that the UL interval is a fixed value. For example, a node may determine a UL interval of 256 ms. In other embodiments, the interval may be configured to be inserted after a specific period of time. For example, the period of the interval, P Gap It can be configured as 160ms, 256ms or 1024ms. In the case where the interval is defined as periodic, the period of the interval includes UL transmission. For example, the period of the interval and the first UL transmission is shown by 803.

[0059] At 804, more UL messages may be sent during the second transmission. In some embodiments, due to the repetitive nature of transmissions over the NTN network, the message in the first UL transmission may be sent again.

[0060] The UE may send an UL message, insert a periodic UL interval to perform frequency correction, and then send more UL messages. In some embodiments, the subsequent transmission occurs just after the UL interval. In other embodiments, the subsequent transmission occurs at a certain time period after the UL interval.

[0061] User equipment configured with a non-terrestrial network module to correct frequency errors during uplink intervals

[0062] The UE may receive the navigation signal based on the capability type of the UE. For example, if the UE has an NTN module, the UE may be able to receive the navigation signal. The navigation signal may be, for example, a Global Navigation Satellite System (GNSS) signal.

[0063] In some embodiments, communication may be performed with low earth orbit ("LEO") satellites. LEO satellites are faster than GEO satellites, which means that the beam pointing to the UE changes more frequently to account for updated LEO positions. Therefore, the UE and LEO satellites may require more frequent DL synchronization.

[0064] In other embodiments, during the UL interval, the frequency error may be compensated by the assistance of navigation signals (eg, GNSS signals) when communicating with the NTN network. The assistance provided by the GNSS signals may save power and improve resource utilization efficiency.

[0065] GNSS signals can be used to help the UE determine the frequency error or correct the frequency to a reasonable range during the UL interval. The UE may include a GNSS module that can estimate the frequency error of the crystal oscillator via the received periodic GNSS signal. During the UL interval, when the UE device is not transmitting, the UE can receive and process several cycles of the GNSS signal to measure the frequency error. In other words, the length of the time interval can be NxT measure , N is an integer that depends on the range of the accumulated frequency drift and the capabilities in the UE. measure is the measurement period. In some embodiments, T measure It may be the period of the GNSS signal. Therefore, the UE may use the GNSS signal to determine the frequency offset.

[0066] In some embodiments, during the UL interval, in addition to using one or more DL messages, the frequency error in the NTN network can also be compensated with the assistance of GNSS signals. The DL message may include at least one of system information, synchronization signals, cell-specific reference signals, or channel state information reference signals ("CSI-RS"). As described above, devices that communicate via HD-FDD, most NB-IoT devices, may not transmit and receive at the same time. Therefore, for single-carrier deployments, when the UE needs to transmit via UL and receive via DL, it may be necessary to switch between carrier signals. When the UE switches to a dedicated DL carrier, the DL synchronization between devices can be retuned. Synchronization signals and reference signals can be sent. Since GNSS signals are used and fewer DL resources are used, GNSS signals can improve the accuracy of frequency error estimation and shorten the UL compensation interval. At the end of the UL interval, the UE can switch to UL transmission with frequency correction.

[0067] In some embodiments, the UE may detect the absence of the navigation signal during the UL interval. In these cases, during the UL interval, the UE may switch to receive DL messages, ie, messages sent from the node.

[0068] In the above embodiments, the UE may switch to a dedicated DL carrier and then switch back to a dedicated UL carrier. In some embodiments, during the UL interval, the UE device may stop sending, receiving, and processing DL messages. The UE may use GNSS signals to measure the frequency offset and then determine the frequency error. In other embodiments, while stopping the first transmission, the UE device may switch to receiving DL messages. During the UL interval, the UE may use at least one of the navigation signal or the DL message to measure the frequency offset.

[0069] The length of the UL interval may be determined by the wireless communication node as NxT measure , where N is an integer that depends on the accumulated frequency drift and the range of the GNSS module in the UE, and T measure is the measurement period. In some embodiments, T measure It can be the period of the GNSS signal. In other embodiments, T measure It can be the period of the DL signal. In an alternative embodiment, T measure It can be the period of both GNSS signal and DL signal.

[0070] In other embodiments, the GNSS signal may be lost or interrupted. When the UE attempts to process the GNSS signal during the UL interval, there may be a failed detection. When the UE loses the GNSS signal, a resolution mechanism may occur.

[0071] One resolution mechanism may include the UE attempting to recover the GNSS connection during a time period that is the same as the UL interval, as described above. In other words, the UE may determine the absence of a navigation signal and attempt to establish a connection to receive the navigation signal for a time period that is less than or equal to the UL interval. An alternative resolution mechanism may include the UE switching to a dedicated DL carrier to attempt to receive the DL signal. As described above, the UE is able to perform frequency error correction using only the DL signal.

[0072] In some embodiments, the UE may not be able to synchronize with the node from which it is trying to receive a DL message. Subsequently, the UE may not be able to measure the DL message to correct the frequency error. In these cases, the UE may retry synchronization with the sending node during the UL interval. In some embodiments, the time for synchronization with the sending node may exceed the UL interval. In other words, the UE may continue to try to synchronize with the sending node until the UE receives the DL message. In an alternative embodiment, the time for synchronization with the second device may occur during the UL interval. In other embodiments, the time for synchronization with the second device may take longer than the UL interval. In these cases, the UE may continue to try to synchronize with the second device even if the synchronization time is longer than the UL interval. When synchronizing and subsequently receiving a DL message, the UE may correct its frequency error and continue to send to the NTN network.

[0073] A user equipment configured without a GNSS module for correcting a frequency error during an uplink interval,

[0074] In some embodiments, the UE may not have a GNSS module. Examples of these devices may be NB-IoT devices. In these cases, the UE may perform different functions to compensate for the frequency error or correct the frequency to a reasonable range. In other words, the UE may perform periodic frequency error correction in the UL compensation interval, where the UL compensation interval occurs before the last symbol of the transmission of x subframes. The length of the UL compensation interval is based on the subcarrier spacing of the UL transmission.

[0075] In some embodiments, during the UL interval, the frequency error in the NTN network can be corrected by taking into account the temperature variation. As described above, the temperature variation may cause the crystal oscillator to output an imperfect frequency. Therefore, by taking into account the temperature variation between the UE and the second device, the UE can correct the frequency error.

[0076] In some embodiments, the UE may switch to a dedicated DL carrier during the UL interval to attempt to receive DL messages and measure the frequency error. The UE may interrupt its UL transmission to compensate for the frequency error or correct the frequency error to a reasonable range.

[0077] As described above, the UE is able to perform frequency error correction using only DL signals. The UE may need to switch the carrier signal from the UL carrier to the DL carrier. When the UE switches to a dedicated DL carrier, the DL synchronization between the device and the node should be retuned. The DL signal may include at least one of system information, a synchronization signal, or a cell-specific reference. The UE may switch to DL during the interval for frequency error correction and then switch back to UL for continuous UL transmission.

[0078] User equipment corrects frequency error in the absence of uplink gaps

[0079] In some embodiments, the UE can correct the frequency error that occurs when communicating in the NTN network by implementing a temperature compensated crystal oscillator. As described above, temperature changes may cause the crystal oscillator to output an imperfect frequency. Therefore, by implementing a temperature compensated crystal oscillator, the UE can correct the frequency error.

[0080] The base station corrects the frequency error by configuring the interval.

[0081] In some embodiments, the base station may configure a time interval between two DL transmissions. The first transmission may last for a first time period. The first time period may be determined by evaluating when a frequency offset at a UE receiver meets a threshold. In one embodiment, the threshold is a fixed value for a UE capability class defined by whether the UE supports GNSS or other NTN modules. Correspondingly, the duration of the first time period is configured as a fixed value.

[0082] The base station may inform the UE of the configuration of the time interval. The interval configuration information may be sent before the first transmission. In another embodiment, there may be a default time interval configuration for the category of UE capabilities. That is, the duration of the time interval is a fixed value.

[0083] Although various embodiments of the present solution have been described above, it should be understood that they are presented only by way of example and not by way of limitation. Similarly, various figures may depict example architectures or configurations, which are provided so that those of ordinary skill in the art can understand the example features and functions of the present solution. However, these persons should understand that the solution is not limited to the example architectures or configurations shown, but may be implemented using various alternative architectures and configurations. In addition, as those of ordinary skill in the art should understand, one or more features of an embodiment may be combined with one or more features of another embodiment described herein. Therefore, the breadth and scope of the present disclosure should not be limited by any of the illustrative embodiments described above.

[0084] It should also be understood that any reference to an element using names such as "first", "second", etc. herein does not generally limit the number or order of these elements. Instead, these names can be used herein as a convenient means of distinguishing two or more elements or element instances. Therefore, reference to a first element and a second element does not mean that only two elements can be used, or that the first element must be located before the second element in some way.

[0085] In addition, it should be understood by those skilled in the art that any of a variety of different technologies and techniques may be used to represent information and signals. For example, data, instructions, commands, information, signals, bits, and symbols that may be referenced in the above description may be represented by voltage, current, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0086] It will also be understood by those of ordinary skill in the art that any of the various illustrative logic blocks, modules, processors, means, circuits, methods, and functions described in conjunction with the aspects disclosed herein may be implemented by electronic hardware (e.g., digital implementation, analog implementation, or a combination of the two), firmware, various forms of programs or design codes incorporating instructions (which, for convenience, may be referred to herein as "software" or "software modules"), or any combination of these technologies. In order to clearly illustrate this interchangeability of hardware, firmware, and software, various illustrative components, blocks, modules, circuits, and steps have been generally described above in terms of their functions. Whether such functionality is implemented as hardware, firmware, or software, or a combination of these technologies, depends on the specific application and the design constraints imposed on the entire system. A skilled technician may implement the described functionality in various ways for each specific application, but such implementation decisions will not result in a departure from the scope of this disclosure.

[0087] In addition, it should be understood by those of ordinary skill in the art that the various illustrative logic blocks, modules, devices, components, and circuits described herein may be implemented or performed within an integrated circuit (IC) that includes a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable logic device, or any combination thereof. The logic blocks, modules, and circuits may further include antennas and / or transceivers to communicate with various components within a network or within a device. The general purpose processor may be a microprocessor, but in an alternative, the processor may be any conventional processor, controller, or state machine. The processor may also be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors combined with a DSP core, or any other suitable configuration to perform the functions described herein.

[0088] If implemented in software, the function may be stored as one or more instructions or codes on a computer-readable medium. Therefore, the steps of the method or algorithm disclosed herein may be implemented as software stored on a computer-readable medium. Computer-readable media include computer storage media and communication media, and communication media include any media that enables a computer program or code to be transferred from one place to another. The storage medium may be any available medium that can be accessed by a computer. By way of example and not limitation, such a computer-readable medium may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage device, or any other medium that can be used to store the desired program code in the form of instructions or data structures and can be accessed by a computer.

[0089] In this application, the term "module" as used herein refers to software, firmware, hardware, and any combination of these elements for performing the relevant functions described herein. In addition, for the purpose of ease of discussion, various modules are described as discrete modules; however, it is obvious to a person of ordinary skill in the art that two or more modules can be combined to form a single module that performs the relevant functions according to an embodiment of the present solution.

[0090] In addition, in the embodiment of the present solution, memory or other memory and communication components can be used. It should be understood that, for the sake of clarity, the above description has described the embodiment of the present solution with reference to different functional units and processors. However, it is obvious that any appropriate functional distribution between different functional units, processing logic elements or domains can be used without affecting the present solution. For example, the function shown as being performed by a separate processing logic element or controller can be performed by the same processing logic element or controller. Therefore, reference to a specific functional unit is only a reference to an appropriate means for providing the described function, rather than an indication of a strict logical or physical structure or organization.

[0091] Various modifications to the embodiments described in this disclosure will be apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments without departing from the scope of this disclosure. Therefore, this disclosure is not intended to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the novel features and principles disclosed herein, as described in the following claims.

Claims

1. A wireless communication method, comprising: receiving, by a wireless communication device, a configuration from a wireless communication node, the configuration indicating a time interval determined by the wireless communication node based on a navigation signal; inserting, by the wireless communication device according to a configuration from the wireless communication node, the time interval determined based on the navigation signal between the first transmission and the second transmission, wherein the first transmission comprises the wireless communication device sending a plurality of first uplink messages to the wireless communication node, and the second transmission comprises the wireless communication device sending a plurality of second uplink messages to the wireless communication node; receiving, by the wireless communication device, the navigation signal during the time interval; and A value for a timing adjustment or a value for a frequency adjustment is determined by the wireless communication device during the time interval based on the navigation signal.

2. The wireless communication method according to claim 1, wherein: The time interval is at least one of the following units: a symbol, a time slot, a subframe, one or more milliseconds, and a period of the navigation signal.

3. The wireless communication method according to claim 1, A plurality of downlink messages are received by the wireless communication device during the time interval.

4. The wireless communication method according to claim 3, wherein: The plurality of downlink messages include at least one of: system information, a synchronization signal, a cell-specific reference signal, or a channel state information reference signal CSI-RS.

5. The wireless communication method according to claim 3, further comprising: determining, by the wireless communication device, an absence of the navigation signal during the time interval; as well as Switching, by the wireless communication device, during the time interval to receive the plurality of downlink messages from the wireless communication node.

6. The wireless communication method according to claim 5, further comprising: determining, by the wireless communication device, a failure to synchronize with the wireless communication node during the time interval after the switching; as well as Synchronization with the wireless communication node is continued by the wireless communication device during the time interval.

7. The wireless communication method according to claim 5, further comprising: determining, by the wireless communication device, a failure to synchronize with the wireless communication node during the time interval after the switching; as well as After the time interval has elapsed, synchronization with the wireless communication node is continued by the wireless communication device.

8. The wireless communication method according to claim 1, A value for a timing adjustment or a value for a frequency adjustment is applied by the wireless communication device to the second transmission.

9. The wireless communication method according to claim 1, further comprising: ceasing, by the wireless communication device, to receive any downlink messages from the wireless communication node during the time interval; as well as A frequency offset is measured by the wireless communication device using the navigation signal during the time interval.

10. The wireless communication method according to claim 1, further comprising: ceasing, by the wireless communication device, the first transmission during the time interval; as well as A frequency offset is measured by the wireless communication device using the navigation signal during the time interval.

11. The wireless communication method according to claim 1, wherein: Each of the first transmission and the second transmission includes at least one of: a physical uplink shared channel PUSCH and a physical random access channel PRACH.

12. The wireless communication method according to claim 1, further comprising: Determining, by the wireless communication device, to send a plurality of subsequent uplink messages; as well as The wireless communication device sends the multiple subsequent uplink messages in response to the determination, and the time interval is periodically inserted after a corresponding time period of each subsequent uplink message in the sending of the multiple subsequent uplink messages by the wireless communication device.

13. The wireless communication method according to claim 1, further comprising: while stopping the first transmission, switching, by the wireless communication device, to receive a plurality of downlink messages from the wireless communication node; as well as A frequency offset is measured by the wireless communication device during the time interval using at least one of the navigation signal or the plurality of downlink messages.

14. The wireless communication method according to claim 1, further comprising: determining, by the wireless communication device, an absence of the navigation signal during the time interval; as well as A connection is established by the wireless communication device during the time interval to receive the navigation signal within a certain time period, wherein the time period is less than or equal to the time interval.

15. A wireless communication method, comprising: determining, by the wireless communication node based on the navigation signal, a time interval to be inserted between the first transmission and the second transmission, wherein the first transmission comprises the wireless communication device sending a plurality of first uplink messages to the wireless communication node, and the second transmission comprises the wireless communication device sending a plurality of second uplink messages to the wireless communication node; and sending, by the wireless communication node, to the wireless communication device, a configuration indicating a time interval determined based on the navigation signal, The navigation signal is received by the wireless communication device during the time interval, so that the wireless communication device can determine a value for timing adjustment or a value for frequency adjustment based on the navigation signal.

16. The wireless communication method according to claim 15, wherein: The first transmission lasts for a first time period, and the wireless communication method further includes: The first time period is determined by the wireless communication node by determining that at least one of a frequency offset and a timing offset satisfies a threshold.

17. The wireless communication method according to claim 15, wherein: The wireless communication node indicates the configuration of the time interval via higher layer signaling.

18. The wireless communication method according to claim 17, wherein: The configuration of the time interval includes at least one of the following: a time domain length of the time interval and a period of the time interval.

19. The wireless communication method according to claim 15, wherein: The configuration of the time interval is based on the capability of the wireless communication device, and the capability is reported from the wireless communication device.

20. The wireless communication method according to claim 16, wherein: The time interval begins immediately after the first time period ends.

21. The wireless communication method according to claim 15, wherein: The time interval is determined based on the frequency offset and at least one of: one or more downlink resource amounts and one or more Global Navigation Satellite System (GNSS) resource amounts.

22. The wireless communication method according to claim 15, wherein: The time interval is also determined based on a subcarrier spacing SCS of at least one of the first transmission or the second transmission.

23. The wireless communication method according to claim 15, wherein: The navigation signal comprises a Global Navigation Satellite System (GNSS) signal.

24. The wireless communication method according to claim 15, wherein: The time interval is at least one of the following units: a symbol, a time slot, a subframe, one or more milliseconds, and a period of the navigation signal.

25. The wireless communication method according to claim 15, further comprising: A plurality of downlink messages are sent by the wireless communication node to the wireless communication device during the time interval.

26. The wireless communication method according to claim 25, wherein: The plurality of downlink messages include at least one of: system information, a synchronization signal, a cell-specific reference signal, and a channel state information reference signal CSI-RS.

27. The wireless communication method according to claim 15, wherein: Each of the first transmission and the second transmission includes at least one of: a physical uplink shared channel PUSCH and a physical random access channel PRACH.

28. A wireless communication device comprising a processor and a memory, wherein: The processor is configured to read code from the memory and implement the method according to any one of claims 1 to 27.

29. A computer program product comprising computer readable program medium code stored thereon, which, when executed by a processor, causes the processor to implement the method according to any one of claims 1 to 27.

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