Sidelink communication in a cellular communication network

Abstract

According to example aspects of the present application, there is provided a method comprising determining, by a network node, a timing offset (TO A ) for a first wireless link, determining, by the network node, a timing offset (TO B ) for a second wireless link, determining, by the network node, a timing offset (TO C ) for a third wireless link, calculating, by the network node, a timing calibration value for a first sidelink device using the timing offset (TO A ) for the first wireless link, the timing offset (TO B ) for the second wireless link, and the timing offset (TO C ) for the third wireless link, and transmitting, by the network node, at least the timing calibration value for the first sidelink device.

Description

Technical Field

[0001] The various example embodiments generally relate to cellular communication networks, and more specifically to sidechain communication in such networks. Background Technology

[0002] A sidechain (SL) is a direct communication link between User Equipments (UEs) in a cellular network, allowing UEs to communicate without going through a base station (BS). Communication via SL can be enabled in various cellular networks, such as those operating under 5G Radio Access Technology (NR). 5G NR is also known as New Radio Access Technology. The 3rd Generation Partnership Project (3GPP) develops standards for 5G / NR, and several topics in 3GPP discussions relate to SL communication. According to these discussions, there is a need for improved methods, apparatus, and computer programs related to the use of SL. Such improvements can also be used in other cellular networks. Summary of the Invention

[0003] The subject matter of the independent claims is provided in several respects. Several example embodiments are defined in the dependent claims.

[0004] The scope of protection sought by the various exemplary embodiments of the present invention is defined by the independent claims. Exemplary embodiments and features (if any) described in this specification that are not within the scope of the independent claims are to be interpreted as examples useful for understanding the various exemplary embodiments of the invention. According to a first aspect of the present invention, an apparatus is provided comprising: determining a timing offset (TO) of a first wireless link. A The components, wherein the first wireless link is the link between the wireless network node and the first sidechain device, and the timing offset (TO) of the first wireless link. A The calculated bidirectional delay of the first wireless link and the measured bidirectional delay of the first wireless link are used to determine the timing offset (TO) of the second wireless link. B The components, wherein the second wireless link is the link between the wireless network node and the second sidechain device, and the timing offset (TO) of the second wireless link. B The calculated bidirectional delay based on the second wireless link and the measured bidirectional delay based on the second wireless link; used to determine the timing offset (TO) of the third wireless link. C The components, wherein the third wireless link is the link between the first sidechain device and the second sidechain device, and the timing offset (TO) of the third wireless link. C The bidirectional delay calculated based on the third wireless link and the bidirectional delay measured by the third wireless link; used for timing offset (TO) of the first wireless link. A Timing offset of the second wireless link (TO)B ) and timing offset of the third wireless link (TO) C The apparatus of the first aspect includes components for calculating the timing calibration value of the first sidechain device; and components for at least transmitting the timing calibration value of the first sidechain device. The apparatus of the first aspect may include a network node, or a control device configured to potentially control its operation when installed therein.

[0005] According to a second aspect of the present invention, an apparatus is provided, the apparatus comprising: a component for receiving a timing calibration value of a first sidechain device from a network node, the timing calibration value being based on a timing offset (TO) of a first wireless link. A Timing offset of the second wireless link (TO) B ) and timing offset of the third wireless link (TO) C The device comprises a first wireless link between a wireless network node and a first sidechain device, a second wireless link between a wireless network node and a second sidechain device, and a third wireless link between the first sidechain device and the second sidechain device; and components for compensating for transmission and / or reception using timing calibration values. The device may include the first sidechain device or a control device configured to potentially control its operation when installed therein.

[0006] According to a third aspect of the present invention, a first method is provided, the method comprising: determining, by a network node, a timing offset (TO) of a first wireless link. A ), where the first wireless link is the link between the wireless network node and the first sidechain device, and the timing offset of the first wireless link (TO) A The timing offset (TO) of the second wireless link is determined by the network node based on the calculated bidirectional delay of the first wireless link and the measured bidirectional delay of the first wireless link. B The second wireless link is the link between the wireless network node and the second sidechain device, and the timing offset of the second wireless link (TO) B The bidirectional delay is calculated based on the second wireless link and measured based on the second wireless link; the timing offset of the third wireless link is determined by the network node (TO). C The third wireless link is the link between the first sidechain device and the second sidechain device, and the timing offset (TO) of the third wireless link is... C The bidirectional delay is calculated based on the third wireless link and measured based on the third wireless link; the timing offset (TO) of the first wireless link is used by the network node. A Timing offset of the second wireless link (TO) B ) and timing offset of the third wireless link (TO) CThe first method involves calculating the timing calibration value of the first sidechain device and transmitting, at least, the timing calibration value of the first sidechain device by the network node. This first method can be performed by the network node or a control device configured to potentially control its operation when installed therein.

[0007] According to a fourth aspect of the invention, a second method is provided, the method comprising: receiving a timing calibration value from a network node by a first sidechain device, the timing calibration value being based on a timing offset (TO) of a first wireless link. A Timing offset of the second wireless link (TO) B ) and timing offset of the third wireless link (TO) C The method comprises a first wireless link between a wireless network node and a first sidechain device, a second wireless link between a wireless network node and a second sidechain device, and a third wireless link between the first sidechain device and the second sidechain device; and the first sidechain device compensates for transmission and / or reception using a timing calibration value. The second method can be performed by the first sidechain device or a control device configured to potentially control its operation when installed therein.

[0008] According to a fifth aspect of the invention, an apparatus is provided, the apparatus comprising at least one processing core and at least one memory including computer program code, the at least one memory and the computer program code being configured together with the at least one processing core to cause the apparatus to at least perform: determining a timing offset (TO) of a first wireless link. A ), where the first wireless link is the link between the wireless network node and the first sidechain device, and the timing offset of the first wireless link (TO) A Based on the calculated bidirectional delay of the first wireless link and the measured bidirectional delay of the first wireless link, determine the timing offset (TO) of the second wireless link. B The second wireless link is the link between the wireless network node and the second sidechain device, and the timing offset of the second wireless link (TO) B The bidirectional delay calculated based on the second wireless link and the bidirectional delay measured by the second wireless link are used to determine the timing offset (TO) of the third wireless link. C The third wireless link is the link between the first sidechain device and the second sidechain device, and the timing offset (TO) of the third wireless link is... C The bidirectional delay is calculated based on the third wireless link and measured based on the third wireless link; the timing offset (TO) of the first wireless link is used. A Timing offset of the second wireless link (TO) B ) and timing offset of the third wireless link (TO) CThe device calculates the timing calibration value of the first sidechain device and at least transmits the timing calibration value of the first sidechain device. The device may include a network node or a control device configured to control its operation when installed therein.

[0009] According to a sixth aspect of the invention, an apparatus is provided, the apparatus comprising at least one processing core, at least one memory including computer program code, the at least one memory and the computer program code being configured together with the at least one processing core to cause the apparatus to at least perform: receiving a timing calibration value from a network node for a first sidechain device, the timing calibration value being based on a timing offset (TO) of a first wireless link. A Timing offset of the second wireless link (TO) B ) and timing offset of the third wireless link (TO) C The device comprises a first wireless link between a wireless network node and a first sidechain device, a second wireless link between a wireless network node and a second sidechain device, and a third wireless link between the first sidechain device and the second sidechain device; and compensates for transmission and / or reception using timing calibration values. The device may include the first sidechain device or a control device configured to potentially control its operation when installed therein.

[0010] According to a seventh aspect of the invention, a non-transitory computer-readable medium is provided, on which a set of computer-readable instructions are stored, which, when executed by at least one processor, cause a device to perform at least a first method or a second method. According to an eighth aspect of the invention, a computer program including instructions is provided, which, when executed by a device, cause the device to perform the first method or the second method. Attached Figure Description

[0011] Figure 1 A communication network according to at least some example embodiments is shown;

[0012] Figure 2 Timing error sources according to at least some example embodiments are shown;

[0013] Figure 3 The calibration process according to at least some example embodiments is shown;

[0014] Figure 4 A first network scenario for calculating timing calibration values ​​is illustrated according to at least some example embodiments;

[0015] Figure 5 A second network scenario for calculating timing calibration values ​​is illustrated according to at least some example embodiments;

[0016] Figure 6 Signaling diagrams according to at least some example embodiments are shown;

[0017] Figure 7 An example apparatus capable of supporting at least some of the example embodiments is shown;

[0018] Figure 8 A flowchart of a first method according to at least some example embodiments is shown;

[0019] Figure 9 A flowchart of a second method according to at least some example embodiments is shown;

[0020] Figure 10 An example of calculating timing error according to at least some example embodiments is shown;

[0021] Figure 11 Examples of calculating timing errors without calibration are shown according to at least some example embodiments; and

[0022] Figure 12 An example of calculating timing error using calibration is shown according to at least some example embodiments. Detailed Implementation

[0023] Embodiments of the present invention provide enhancements to sidelink communication in cellular communication networks. More specifically, embodiments of the present invention are capable of estimating timing calibration values ​​for a wireless network node, a first sidelink (SL) device, and a second SL device. For example, the timing calibration of the first SL device can be calculated using the timing offset of the wireless network, the wireless link between the first SL device and the second SL device, wherein each timing offset can be determined by subtracting the calculated two-way delay of the corresponding wireless link from the measured two-way delay of the corresponding link. Therefore, timing calibration values ​​can be calculated without relying on, for example, a Global Navigation Satellite System (GNSS).

[0024] Figure 1 A communication network according to at least some example embodiments is illustrated. Figure 1 An example scenario could exist where a cellular communication network exists, comprising three SL devices configured to communicate using SL communication, and network nodes. More specifically, Figure 1 The cellular communication network includes a first SL device 110, a second DL device 112, a third SL device 114, a base station BS 120, and a core network 130. BS 120 can be referred to as a wireless network node; that is, although BS 120 is used as an example, according to embodiments of the invention, generally any wireless network node (such as a relay) can perform the tasks of BS 120. In some embodiments, the core network 130 may include network nodes 132, such as location management functions (LMFs).

[0025] The first SL device 110 and the second SL device 112 can be connected to each other via air interface 105. Similarly, the first SL device 110 and the third SL device 114 can be connected to each other via air interface 105. The second SL device 112 and the third SL device 114 can also be connected to each other via air interface 105. The first SL device 110 and the second SL device 112 can be further connected to BS 120 or another BS via air interface 115. The third SL device 114 may or may not be connected to BS 120.

[0026] SL devices 110, 112, and 114 may include, for example, smartphones, cellular phones, machine-to-machine (M2M) nodes, machine-type communication (MTC) nodes, Internet of Things (IoT) nodes, automotive telemetry units, laptops, tablets, or virtually any suitable wireless terminal. BS 120 may be a network entity that configures some or all of the control information and allocates at least some resources to SL devices 110, 112, and 114. In some example embodiments, BS 120 may be considered a service node for SL devices 110 and 112.

[0027] The air interface 105 between SL devices 110, 112, and 114 can be configured according to the Radio Access Technology (RAT) supported by SL devices 110, 112, and 114. Similarly, the air interface 115 between the first SL device 110 and BS 120 can be configured according to the RAT supported by the first SL device 110 and BS 120. Examples of cellular RATs include Long Term Evolution (LTE), New Radio (NR), also known as 5G Radio Access Technology, and MulteFire. For example, cellular RATs can be standardized by the 3GPP (3rd Generation Partnership Project). Therefore, SL devices 110, 112, and 114, as well as BS 120, can also be configured to operate according to 3GPP standards.

[0028] BS 120 can be connected to the core network 130 directly or via at least one intermediate node through wired interface 125. The core network 130 can also be connected to another network (via interface 135). Figure 1 (Not shown in the diagram) Coupled, this other network can provide connectivity to other networks, such as via the Global Interconnect Network. BS 120 can be connected directly to core network 130 or to another core network, either directly or via at least one intermediate node.

[0029] Embodiments of the present invention may involve using SL-based UE-to-UE communication between SL devices 110, 112, and 114. SL may refer to a direct communication link between UEs 110, 112, and 114 in a cellular communication network, and the UEs may communicate via the SL without going through BS 120. That is, in some embodiments, SL devices 110, 112, and 114 may generally be referred to as device-to-device D2D wireless terminals, including D2D user equipment (UE) or D2D terminals in non-cellular communication networks, such as wireless local area networks (WLANs).

[0030] As a first example, embodiments of the present invention may relate to positioning and, for example, be applied in the context of vehicle-to-everything (V2X) communication. For instance, in the case of 3GPP specifications, V2X positioning requirements can be found at least in 3GPP standard specifications TS22.261 V18.3.0 (2021-06) or TS 22.261 V17.7.0 (2021-06), where Clause 7.3.2.2 summarizes the high-accuracy positioning requirements for 5G systems and specifies that these requirements include V2X. Table 7.3.2.2-1 of 3GPP standard specifications TS22.261 V18.3.0 (2021-06) or TS 22.261 V17.7.0 (2021-06) defines seven different positioning service levels for horizontal and vertical accuracy, positioning service availability, and positioning service latency. 3GPP standard specification TS 22.186 V16.2.0 (2019-06) specifies the relative lateral positioning requirements for general V2X use cases and the relative longitudinal positioning requirements for formation use cases in clauses 5.1 and 5.2. Positioning requirements for V2X services can be categorized into, for example, three groups: a first group with accuracy of tens of meters, a second group with lane-level accuracy, and a third group with accuracy below meters. Furthermore, it may be necessary to provide positioning technologies that support advanced V2X applications and function correctly even in various out-of-coverage scenarios.

[0031] Location requirements in V2X can be service-dependent. Location services should be provided indoors, outdoors, in tunnels, and at speeds up to 250 km / h. These requirements should be met both within and outside network coverage areas, as long as the sidechain device is running a V2X application with location requirements. These requirements should also be met when GNSS-based positioning is unavailable or inaccurate.

[0032] As a second example, embodiments of the present invention can be applied to the context of public safety. Also in the context of public safety, location services should be provided both indoors and outdoors, and these requirements should be met both when the sidechain device is within and outside network coverage. These requirements should also be met when GNSS-based positioning is unavailable or insufficiently accurate.

[0033] In environments with densely distributed base stations (BS) and good coverage, fairly good timing accuracy can be expected, enabling the estimation of the correct location of mobile devices in such environments. However, in limited BS deployment scenarios, the limitation of using SL (Simultaneous Positioning) to estimate the location of mobile devices is the cumulative accuracy of SL timing estimates. Therefore, accurate timing is required.

[0034] Accurate timing for SL devices can be achieved using GNSS for better positioning estimates and accurate time references. GNSS can be suitable for SL devices if space, price, and "open-air" conditions are not an issue; however, it may be undetectable for SL devices located indoors, in street canyons, disaster areas, and other locations. Furthermore, adding GNSS is not a viable solution for SL devices installed in smart traffic lights where space may be limited. Another issue related to using GNSS alone is its susceptibility to interference / spoofing.

[0035] Therefore, embodiments of the present invention enable accurate timing calibration of SL devices, for example, for positioning in environments at least partially and outside the coverage area. In some embodiments, SL-assisted scenarios can be considered, where SL devices such as roadside units can be static within the coverage area and within the line-of-sight (LoS).

[0036] Figure 2 Examples of timing error sources according to at least some example embodiments are shown. Various timing error sources can affect timing accuracy. For example, in the case of communication between the first SL device 110 and the BS 120, on the BS 120 side, the BS reception timing error BS_Te and the BS time alignment error TAE can cause timing errors. Furthermore, in this case, on the first SL device 110 side, the downlink frame synchronization error DFSE, the time alignment step size TASS, and the accuracy of the time alignment adjustment TAA granularity can also cause timing errors. The accumulated timing errors will then again affect the timing accuracy of the sidechain devices, thereby affecting possible position estimation. Figure 2 The diagram shows the propagation delay (PD), baseband (BB) unit, radio unit (RU), and radio frequency (RF) unit.

[0037] Embodiments of the present invention thus improve timing accuracy by minimizing the timing errors of SL devices in a network configured with at least one BS 120 and at least two SL devices (such as SL devices 110 and 112). Timing calibration between the BS 120 and SL devices 110 and 112 can be performed, and the timing error between the BS 120 and SL devices 110 and 112 can be minimized. By minimizing the timing errors of SL devices 110 and 112, more accurate position estimation can be performed in environments where SL devices 110 and 112 are used in a positioning configuration, for example, for any moving third SL device 114 (such as a UE, robot, or vehicle).

[0038] In some embodiments, SL devices 110 and 112 may be static. Furthermore, the locations of BS 120 and SL devices 110 and 112 may be known. In some embodiments, SL devices 110 and 112 may be connected to the same receiving unit and antenna panel of BS 120 to ensure that the delay of SL devices 110 and 112 through the receiving unit of BS 120 is the same.

[0039] Figure 3 An example of a calibration process according to at least some example embodiments is shown. By knowing the timing tolerances of the components, the calibration process can be triggered, for example, at the initial startup of the SL, and retried in the event of unexpected timing drift that can be detected by BS 120 and / or SL devices 110 and 112. Alternatively, calibration can be retried at fixed intervals. The locations of BS 120 and SL devices 110 and 112 can be known before the calibration process is initiated. The calibration process can be performed by any network node, such as LMF 132, even if BS 120 is used as a... Figure 3 Related examples.

[0040] In step 302, BS 120 can determine that a connection exists between BS 120 and at least SL devices 110 and 112. Then, in step 304, BS 120 can check whether a Loss of Memory (LOS) connection exists on the wireless link between BS 120 and at least SL devices 110 and 112. If there is no LOS connection on at least one link, the calibration process can terminate. However, if an LOS connection exists, BS 120 can decide to continue the calibration process, and in step 306, BS 120 can measure the bidirectional delay of a first wireless link, where the first wireless link is the link between the first SL device 110 and BS 120. Furthermore, BS 120 can measure the bidirectional delay of a second wireless link, where the second wireless link is the link between the second SL device 112 and BS 120. SLs can synchronize with BS 120.

[0041] In step 308, BS 120 can compare the calculated bidirectional delay of the first wireless link with the measured bidirectional delay of the first wireless link to determine the timing offset of the first wireless link. Similarly, BS 120 can compare the calculated bidirectional delay of the second wireless link with the measured bidirectional delay of the second wireless link to determine the timing offset of the second wireless link. Typically, the bidirectional delay of a wireless link can be calculated based on the location of the devices by first calculating the distance between the devices and then calculating the theoretical PD of the wireless link by dividing the distance by the speed of light. The bidirectional delay can then be calculated by multiplying the PD by 2.

[0042] In step 310, BS 120 can determine if any more SL devices are connected to BS 120. If so, BS 120 can also perform steps 302-308 for those SL devices. If not, BS 120 can decide to continue the calibration process, and in step 312, BS 120 can request, for example, the first SL device 110 to measure the bidirectional delay between SL devices 110 and 112. BS 120 can designate the first SL device 110 as the host to perform the delay measurement on a third wireless link, where the third wireless link is the SL between SL device 110 and SL device 112. Alternatively, the measurement can be performed by both SL devices 110 and 112. In step 314, the first SL device 110 can measure the bidirectional delay of the third wireless link. In step 316, the first SL device 110 can transmit the measured bidirectional delay to BS 120.

[0043] In step 318, BS 120 can compare the calculated bidirectional delay of the third wireless link with the measured bidirectional delay of the third wireless link to determine the timing offset of the third wireless link. Then, BS 120 can use the timing offset (A) of the first wireless link, the timing offset (B) of the second wireless link, and the timing offset (C) of the third wireless link to calculate individual timing calibration values ​​for itself and for both SL devices 110 and 112. In step 320, BS 120 can transmit the calibration values ​​to SL devices 110 and 112 for timing compensation.

[0044] Figure 4 An example network scenario for calculating timing calibration values ​​is illustrated, according to at least some example embodiments. Figure 4 In the diagram, the wireless communication link between BS 120 and SL device 110 is denoted by A, the wireless communication link between BS 120 and SL device 112 is denoted by B, and the wireless communication link between SL devices 110 and 112 is denoted by C. The timing calibration values ​​for each of SL devices 110 and 112 and BS 120 can be calculated as follows.

[0045] The timing offsets of the first wireless link A, the second wireless link B, and the third wireless link C can be, for example, by utilizing a combination of Figure 3 The calibration process described is used for calculation. The bidirectional delay for each measurement may include receiver error, transmitter error, and twice the PD of the associated wireless communication link. The bidirectional delay of links A and B can be measured by BS 120, while the bidirectional delay of link C can be measured by a master SL device (such as SL device 110). The theoretical bidirectional delay for each link can be calculated based on the known locations of BS 120 and SL devices 110 and 112, as the known locations can be used to calculate the PD of each link using the speed of light and distance. The theoretical bidirectional delay can be calculated by multiplying the calculated PD by 2.

[0046] Then, the timing offset of the link can be determined based on the calculated bidirectional delay and the measured bidirectional delay of the link. That is, the timing offset of the link can be determined by subtracting the calculated theoretical bidirectional delay from the measured bidirectional delay. For example, the timing offset TO of link A... A The calculation can be performed as follows:

[0047] TO A =D A -PD A (1)

[0048] Where D A It is the bidirectional delay measured on link A, PD A It is the bidirectional delay of the calculation of link A.

[0049] The timing offset of link A may include at least the following delays:

[0050] TO A =BS TX +PD A +SL1 RX +SL1 TX +PD A +BS RX -2*PD A

[0051] TO A ==BS TX +SL1 RX +SL1 TX +BS RX (2)

[0052] The timing offset of link B may include at least the following delays:

[0053] TO B =BS TX +PD B +SL2 RX +SL2TX +PD B +BS RX -2*PD B

[0054] TO B ==BS TX +SL2 RX +SL2 TX +BS RX (3)

[0055] The timing offset of link C may include at least the following delays:

[0056] TO C =SL1 TX +PD C +SL2 RX +SL2 TX +PD C +BS RX -2*PD C

[0057] TO C ==SL1 TX +SL2 RX +SL2 TX +SL1 RX (4)

[0058] Then, the timing offset (TO) of the first wireless link can be used. A Timing offset of the second wireless link (TO) B ) and timing offset of the third wireless link (TO) C This is used to calculate the timing calibration value for each link.

[0059] The timing calibration value of the first SL device 110 can be calculated as follows:

[0060] SL1 = 1 / 2TO C +1 / 2TO A -1 / 2TO B (5)

[0061] SL1 = 1 / 2(SL1) TX +SL2 RX +SL2 TX +SL1 RX )+1 / 2(BS TX +SL1 RX +SL1 TX +BS RX )-1 / 2(BS TX +SL2 RX +SL2 TX +BSRX )

[0062] SL1 = SL1 TX +SL1 RX

[0063] The timing calibration value of the second SL device 112 can be calculated as follows:

[0064] SL2 = 1 / 2TO C +1 / 2TO B -1 / 2TO A (6)

[0065] The timing calibration value for BS 120 can be calculated as follows:

[0066] BS=TO A -SL1 (7)

[0067] Figure 5 A second network scenario for calculating timing calibration values ​​is illustrated according to at least some example embodiments. Figure 4 Compared to the first network scenario shown, Figure 5 The second network scenario shown includes a third SL device 116 and a fourth SL device 118. Figure 5 In the diagram, the wireless communication link between the second SL device 112 and the third SL device 116 is represented by D, the wireless communication link between BS 120 and the third SL device 116 is represented by E, the wireless communication link between BS 120 and the fourth SL device 118 is represented by F, and the wireless communication link between the first SL device 110 and the fourth SL device 118 is represented by G.

[0068] The timing calibration values ​​for the third SL device 110 and the fourth SL device 112 can be calculated as follows.

[0069] The timing offset of link D can include at least the following delays:

[0070] TO D =SL2 TX +PD D +SL3 RX +SL3 TX +PD D +SL2 RX -2*PD D

[0071] TO D =SL2 TX +SL3 RX +SL3 TX +SL2 RX (8)

[0072] The timing offset of link E may include at least the following delays:

[0073] TO E =BS TX +PD E +SL3 RX +SL3 TX +PD E +BS RX -2*PD E

[0074] TO E =BS TX +SL3 RX +SL3 TX +BS RX (9)

[0075] The timing offset of link F may include at least the following delays:

[0076] TO F =BS TX +PD F +SL4 RX +SL4 TX +PD F +SL4 RX -2*PD F

[0077] TO F =BS TX +SL4 RX +SL4 TX +BS RX (10)

[0078] The timing offset of link G can include at least the following delays:

[0079] TO G =SL1 TX +PD G +SL4 RX +SL4 TX +PD G +SL4 RX -2*PD G

[0080] TO G =SL1 TX +SL4 RX +SL4 TX +SL1 RX (11)

[0081] The timing calibration values ​​of the first SL device 110, the second SL device 112, and BS 120 can be calculated using equations (5), (6), and (7), respectively. The timing calibration value of the third SL device 116 can be calculated as follows:

[0082] SL3 = 1 / 2TO D +1 / 2TO E -1 / 2TO B (12)

[0083] The timing calibration value of the fourth SL device 118 can be calculated as follows:

[0084] SL4 = 1 / 2TO G +1 / 2TO F -1 / 2TO A (13)

[0085] In some embodiments, timing calibration values ​​for two different bandwidths corresponding to the calibration improvement can be estimated. For example, three tables can be used to estimate the timing calibration values ​​for the two different bandwidths.

[0086] In some embodiments, LMF 132 can perform the determination of timing offset and the calculation of timing calibration values. For example, if the SL device is reachable via multiple transmit and receive points (TRPs) such as BS 120 and several adjacent BSs, the LMF can at least partially utilize the calibration process.

[0087] As a first example, the LMF 132 can prioritize BSs based on their clock reliability. In this case, the SL device can receive an ordered list of BSs to which it should initiate a timing calibration process. This ordered list can be transmitted by the LMF 132, for example, via the LTE positioning process LPP, for initiating the timing calibration process. The SL device can initiate a timing calibration process with the first BS in the list, calculate at least one PD estimation accuracy metric, such as variance and / or LOS probability, and decide to start the clock alignment process with the first BS based on the calculated metrics, or, if the link quality is low, test the second BS in the list, and so on.

[0088] As a second example, the LMF 132 can select a set of base stations (BSs) with which the SL device should perform clock alignment. This set can be selected based on the timing calibration values ​​of the aforementioned BSs. That is, the set can be selected based on an assessment of the clock accuracy of the aforementioned BSs; specifically, the LMF 132 can select a set of BSs expected to exhibit similar clock accuracy or a set of BSs whose clocks have already been synchronized with each other. The LMF 132 can then transmit information about the selected set, such as the identity of the selected BSs, to the SL device for clock alignment. In this case, the SL device can perform the calibration process via a multi-RTT type method, i.e., triggering a simultaneous RTT session with each BS in the set and using PD estimates to align the clocks, but it may also eliminate device-specific estimation biases via a simple / dual differential method similar to GNSS processing.

[0089] By applying the calibration process, timing errors can be reduced. For example, for the 120kHz subcarrier spacing (SCS) between BS 120, the error can be reduced from 116.25ns to 50ns. And for SL, even greater improvements can be achieved, where the timing error of the uncalibrated system at 120kHz SCS can be 100ns, which can be reduced to 50ns with calibration.

[0090] Figure 6 Signaling diagrams according to at least some example embodiments are shown. (Reference) Figure 1 On the vertical axis, from left to right, are arranged LMF 132, BS 120, first SL 110, and second SL 112. Time progresses from top to bottom.

[0091] In step 602, a connection, such as a Uu interface connection, can be established. In step 604, the calibration process can be initiated by LMF 132, and BS 120 can confirm the initiation of the calibration process. In step 606, BS 120 can transmit a request to the first SL device 110 to request the first SL device 110 to enter calibration mode. In step 608, BS 120 can transmit a request to the second SL device 112 to request the second SL device 112 to also enter calibration mode.

[0092] In step 610, a bidirectional delay measurement can be performed on the first wireless communication link A (i.e., the link between BS 120 and the first SL device 110). That is, BS 120 can transmit calibration reference data, and the first SL device 110 can respond by transmitting calibration reference data. Message exchanges can be repeated until a stable timing measurement value is obtained. BS 120 can determine the bidirectional delay of the link between BS 120 and the first SL device 110 based on the message exchanges. In step 612, BS 120 can perform a bidirectional delay measurement on the second wireless communication link B (i.e., the link between BS 120 and the second SL device 112).

[0093] In step 614, BS 120 can trigger a bidirectional delay measurement on the third wireless communication link C (i.e., the link between the first SL device 110 and the second SL device 112) by transmitting a request to the first SL device 110 to request the first SL device 110 to measure the bidirectional delay of the link between the first SL device 110 and the second SL device 112. In step 616, if an SL has not been established previously, an SL between the first SL device 110 and the second SL device 112 can be established. For example, a connection can be established on a PC5 interface. In step 616, the first SL device 110 can perform a bidirectional delay measurement on the first wireless link. In step 618, the first SL device 110 can transmit an SL time measurement response including the measured bidirectional delay.

[0094] In step 622, BS 120 may transmit a response to LMF 132. This response may include the bidirectional delays of wireless communication links A, B, and C. In step 622, LMF 132 may determine the timing offsets of the first, second, and third wireless links. LMF 132 may also use the timing offsets of the first, second, and third wireless links to calculate timing calibration values ​​for BS 120, the first SL device 110, and the second SL device 112. LMF 132 may calculate the timing calibration values ​​using equations (5), (6), and (7).

[0095] Typically, timing calibration values ​​can be used by the receiving device, and errors may exist in the RTT requests of both the transmitter and receiver, but this does not cause any harmful effects. Therefore, calibration according to embodiments of the invention can locate mobile devices, for example, based on a method in which LMF 132 can request location of the mobile device and the RTT request can be scheduled. Since RTT involves transmitter and receiver delays, it is not necessary to process the calibration values ​​as separate transmitter and receiver values.

[0096] Figure 7 An example apparatus capable of supporting at least some of the example embodiments is illustrated. The illustrated device is 700, which may include, for example, a BS 120 or a first SL device 110, or a device that may control its operation when installed therein. Included in device 700 is a processor 710, which may include, for example, a single-core or multi-core processor, wherein a single-core processor includes one processing core and a multi-core processor includes more than one processing core. Processor 710 typically includes a control device. Processor 710 may include more than one processor. Processor 710 may be a control device. Processor 710 may include at least one application-specific integrated circuit (ASIC). Processor 710 may include at least one field-programmable gate array (FPGA). Processor 710 may include at least one Qualcomm Snapdragon and / or Intel Atom processor. Processor 710 may include, for example, a Cortex-A8 processing core manufactured by ARM Holdings or a Steamroller processing core manufactured by Advanced Micro Devices Corporation. Processor 710 may be a component for performing method steps in device 700, such as determining, initiating transmission, and initiating reception. The processor 710 can be configured, at least in part, by computer instructions to perform actions.

[0097] A processor may include, or be configured as, one or more circuit systems configured to perform stages of the methods according to the example embodiments described herein. As used herein, the term “circuit system” may refer to one or more or all of the following: (a) a hardware circuit implementation only, such as an implementation using only analog and / or digital circuit systems; and (b) a combination of hardware circuits and software, as applicable: (i) a combination of (multiple) analog and / or digital hardware circuits with software / firmware; and (ii) any portion of (multiple) hardware processors (including (multiple) digital signal processors) having software, software, and (multiple) memories, which work together to cause means such as networking functions to perform various functions; and (c) (multiple) hardware circuits and / or (multiple) processors, such as (multiple) microprocessors or portions thereof, which require software (e.g., firmware) to operate, but may be absent when operation does not require the software.

[0098] This definition of circuit system applies to all uses of the term in this application, including in any claim. As another example, as used herein, the term circuit system also covers implementations of only hardware circuitry or processors (or processors in general) or portions thereof and their accompanying software and / or firmware. For example, if applicable to a particular claim element, the term circuit system also covers baseband integrated circuits or processor integrated circuits for mobile devices, or similar integrated circuits in servers, cellular network devices, or other computing or networking devices.

[0099] Device 700 may include memory 720. Memory 720 may include random access memory and / or permanent memory. Memory 720 may include at least one RAM chip. For example, memory 720 may include solid-state, magnetic, optical, and / or holographic memory. Memory 720 may be at least partially accessible by processor 710. Memory 720 may be at least partially included in processor 710. Memory 720 may be a component for storing information. Memory 720 may include computer instructions configured to be executed by processor 710. When computer instructions configured to cause processor 710 to perform certain actions are stored in memory 720, and device 700 as a whole is configured to operate under the guidance of processor 710 using computer instructions from memory 720, processor 710 and / or at least one of its processing cores may be considered to be configured to perform certain actions described above. Memory 720 may be at least partially included in processor 710. Memory 720 may be at least partially external to device 700, but accessible by device 700.

[0100] Device 700 may include a transmitter 730. Device 700 may include a receiver 740. Transmitter 730 and receiver 740 may be configured to transmit and receive information according to at least one cellular or non-cellular standard, respectively. Transmitter 730 may include more than one transmitter. Receiver 740 may include more than one receiver. For example, transmitter 730 and / or receiver 740 may be configured to operate according to Global System for Mobile Communications (GSM), Wideband Code Division Multiple Access (WCDMA), Long Term Evolution (LTE), and / or 5G / NR standards.

[0101] Device 700 may include a near-field communication (NFC) transceiver 750. The NFC transceiver 750 may support at least one NFC technology, such as Bluetooth, Wibree, or similar technologies.

[0102] Device 700 may include a user interface (UI) 760. UI 760 may include at least one of a display, keyboard, touchscreen, vibrator arranged to signal to a user by causing device 700 to vibrate, speaker, and microphone. A user may be able to operate device 700 via UI 760, for example, to accept incoming calls, initiate phone or video calls, browse the internet, manage digital files stored in memory 720 or accessible in the cloud via transmitter 730 and receiver 740 or via NFC transceiver 750, and / or play games.

[0103] Device 700 may include or be arranged to accept a user identity module 770. User identity module 770 may include, for example, a subscriber identity module SIM card that can be installed in device 700. User identity module 770 may include subscription information identifying the user of device 700. User identity module 770 may include password information that can be used to verify the identity of the user of device 700 and / or facilitate the encryption of communication information and billing of the user of device 700 for communications implemented via device 700.

[0104] Processor 710 may be equipped with a transmitter arranged to output information from processor 710 to other devices included in device 700 via electrical leads within device 700. Such a transmitter may include a serial bus transmitter arranged to output information to memory 720 for storage, for example, via at least one electrical lead. Alternatively, the transmitter may include a parallel bus transmitter. Similarly, processor 710 may include a receiver arranged to receive information from other devices included in device 700 via electrical leads within device 700. Such a receiver may include a serial bus receiver arranged to receive information from receiver 740, for example, via at least one electrical lead, for processing within processor 710. Alternatively, the receiver may include a parallel bus receiver.

[0105] Device 700 may include Figure 7 Other devices not shown. For example, in the case where device 700 includes a smartphone, it may include at least one digital camera. Some devices 700 may include a rear camera and a front camera, wherein the rear camera can be used for digital photography, while the front camera is used for video calling. Device 700 may include a fingerprint sensor arranged to at least partially authenticate the user of device 700. In some embodiments, device 700 does not have at least one of the aforementioned devices. For example, some devices 700 may not have an NFC transceiver 750 and / or a user identity module 770.

[0106] Processor 710, memory 720, transmitter 730, receiver 740, NFC transceiver 750, UI 760, and / or user identity module 770 can be interconnected in various ways via electrical leads within device 700. For example, each of the above devices can be individually connected to the main bus within device 700 to allow the devices to exchange information. However, as those skilled in the art will understand, this is merely an example, and various ways of interconnecting at least two of the above devices may be chosen depending on the embodiment, without departing from the scope of the embodiment.

[0107] Figure 8 This is a flowchart of a first method according to at least some example embodiments. The stages of the first method shown may be performed by a network node (such as BS 120 or LMF 132) or a device that may control its operation when installed therein.

[0108] The first method may include: in step 810, determining a timing offset of a first wireless link by a network node, wherein the first wireless link is a link between the wireless network node and a first sidechain device, and the timing offset of the first wireless link is based on a calculated bidirectional delay of the first wireless link and a measured bidirectional delay of the first wireless link. The first method may further include: in step 820, determining a timing offset of a second wireless link by a network node, wherein the second wireless link is a link between the wireless network node and a second sidechain device, and the timing offset of the second wireless link is based on a calculated bidirectional delay of the second wireless link and a measured bidirectional delay of the second wireless link. Furthermore, the first method may include: in step 830, determining a timing offset of a third wireless link by a network node, wherein the third wireless link is a link between the first sidechain device and the second sidechain device, and the timing offset of the third wireless link is based on a calculated bidirectional delay of the third wireless link and a measured bidirectional delay of the third wireless link. The first method may further include: in step 840, calculating a timing calibration value for the first sidechain device by a network node using the timing offsets of the first, second, and third wireless links. Finally, the first method may include: in step 850, transmitting at least the timing calibration value of the first sidechain device.

[0109] Figure 9 This is a flowchart of a second method according to at least some example embodiments. The stages of the second method shown may be performed by the first SL device 110 or a device that may control its operation when installed therein.

[0110] The second method may include: in step 910, the first sidechain device receives a timing calibration value from the network node, the timing calibration value being based on a timing offset of a first wireless link, a timing offset of a second wireless link, and a timing offset of a third wireless link, wherein the first wireless link is the link between the wireless network node and the first sidechain device, the second wireless link is the link between the wireless network node and the second sidechain device, and the third wireless link is the link between the first sidechain device and the second sidechain device. The second method may further include: in step 920, using the timing calibration value to compensate for transmission and / or reception.

[0111] Figure 10 An example of calculating timing error according to at least some example embodiments is shown. Figure 11 An example of calculating timing error without calibration is shown, according to at least some example embodiments. Figure 12 An example of calculating timing error using calibration is shown according to at least some example embodiments.

[0112] It should be understood that the disclosed exemplary embodiments are not limited to the specific structures, process steps, or materials disclosed herein, but can be extended to equivalents that will be recognized by those skilled in the art. It should also be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not restrictive.

[0113] Throughout this specification, any reference to an exemplary embodiment or an exemplary embodiment indicates that a particular feature, structure, or characteristic described in connection with that exemplary embodiment is included in at least one exemplary embodiment. Therefore, the phrases "in one exemplary embodiment" or "in an exemplary embodiment" appearing throughout this specification do not necessarily refer to the same exemplary embodiment. Where numerical values ​​are mentioned using terms such as approximately or substantially, precise numerical values ​​are also disclosed.

[0114] As used herein, for convenience, multiple items, structural elements, constituent elements, and / or materials may be presented in a public list. However, these lists should be interpreted as if each member of the list were individually identified as a separate and unique member. Therefore, without indication to the contrary, no individual member of such a list should be construed as being factually equivalent to any other member in the same list solely based on its presentation in a public group. Furthermore, various exemplary embodiments and examples may be mentioned herein along with alternatives to their various components. It should be understood that such exemplary embodiments, examples, and alternatives should not be construed as factual equivalents of each other, but should be regarded as separate and autonomous representations.

[0115] In the example embodiments, the apparatus, including, for example, BS 120 or the first SL device 110, may further include components for performing the above example embodiments and any combinations thereof. The apparatus may be a cellular communication network such as a 5G network and includes components for operating within the cellular communication network.

[0116] In an example embodiment, a computer program includes instructions that, when executed by a computer, cause the computer to perform a method according to the example embodiments described above and any combination thereof. In an example embodiment, a computer program product embodied on a non-transitory computer-readable medium can be configured to control a processor to perform a process including the example embodiments described above and any combination thereof.

[0117] In an example embodiment, an apparatus including, for example, BS 120 or first SL device 110 may further include at least one processor and at least one memory including computer program code, wherein the at least one memory and the computer program code are configured, together with the at least one processor, to cause the apparatus to perform at least the above example embodiments and any combination thereof. The apparatus may be an apparatus for a cellular communication network, such as a 5G network, and is configured to operate within a cellular communication network.

[0118] Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more exemplary embodiments. Numerous specific details, such as examples of length, width, shape, etc., have been provided in the foregoing description to provide a thorough understanding of exemplary embodiments of the invention. However, those skilled in the art will recognize that the invention can be practiced without one or more of the stated specific details, or using other methods, components, materials, etc. In other instances, well-known structures, materials, or operations have not been shown or described in detail to avoid obscuring aspects of the invention.

[0119] While the foregoing examples illustrate the principles of exemplary embodiments in one or more specific applications, it will be apparent to those skilled in the art that many modifications can be made in terms of form, use, and implementation details without creative ingenuity and without departing from the principles and concepts of the invention. Therefore, the invention is not intended to be limited except as defined by the following claims.

[0120] The verbs “to comprise” and “to include” are used in this document as open-ended restrictions, neither excluding nor requiring the presence of any unlisted features. Unless otherwise expressly stated, the features recited in the dependent claims may be freely combined with each other. Furthermore, it should be understood that the use of “a” or “an” (i.e., the singular form) in this document does not exclude the plural.

[0121] The statement "at least one of A or B" in this document means A, or B, or both A and B.

[0122] Industrial applicability

[0123] At least some of the example implementations have found industrial applications in cellular communication networks such as 5G networks, and may also be found in other cellular communication networks in the future.

[0124] List of abbreviations

[0125] 3GPP: Third Generation Partnership Project

[0126] BB: Baseband

[0127] BS: Base Station

[0128] DFSE: Downlink Frame Synchronization Error

[0129] GNSS: Global Navigation Satellite System

[0130] GSM: Global System for Mobile Communications

[0131] IoT: Internet of Things

[0132] LMF: Location Management Function

[0133] LoS: Line of Sight

[0134] LPP: LTE Positioning Process

[0135] LTE: Long Term Evolution

[0136] M2M: Machine to Machine

[0137] NFC: Near Field Communication

[0138] NR: New Radio

[0139] PD: Propagation Delay

[0140] PSCCH: Physical Sidechain Control Channel

[0141] PSSCH: Physical Sidechain Shared Channel

[0142] QoS: Quality of Service

[0143] RAT: Radio Access Technology

[0144] RRC: Radio Resource Control

[0145] RSRP: Reference Signal Received Power

[0146] RF: Radio Frequency

[0147] RU: Radio Unit

[0148] SCI: Sidechain Control Information

[0149] SL: Sidechain

[0150] TAA: Time alignment adjustment

[0151] TAE: Time Alignment Error

[0152] TASS: Time Alignment Step

[0153] TRP: Transmit and Receive Point

[0154] UE: User Equipment

[0155] UI: User Interface

[0156] V2X: Vehicles to Everything

[0157] WCDMA: Wideband Code Division Multiple Access

[0158] WLAN: Wireless Local Area Network

[0159] List of reference numerals

[0160]

[0161]

Claims

1. A method for communication, comprising: The timing offset TO of the first wireless link is determined by the network node. A The first wireless link is a link between a wireless network node and a first sidechain device, and the timing offset TO of the first wireless link is... A The bidirectional delay calculated based on the first wireless link and the bidirectional delay measured based on the first wireless link, wherein the network node is the wireless network node or a network node in the core network. The timing offset TO of the second wireless link is determined by the network node. B The second wireless link is the link between the wireless network node and the second sidechain device, and the timing offset TO of the second wireless link is... B The bidirectional delay is calculated based on the second wireless link and the bidirectional delay is measured based on the second wireless link; The timing offset TO of the third wireless link is determined by the network node. C The third wireless link is a link between the first sidechain device and the second sidechain device, and the timing offset TO of the third wireless link is... C The bidirectional delay is calculated based on the third wireless link and the bidirectional delay is measured based on the third wireless link; The timing offset TO of the first wireless link is used by the network node. A The timing offset TO of the second wireless link B and the timing offset TO of the third wireless link C The timing calibration value SL1 of the first sidechain device is calculated as follows: ； as well as The network node transmits at least the timing calibration value of the first sidechain device.

2. The method of claim 1, wherein the timing offset is determined by subtracting the calculated bidirectional delay of the corresponding wireless link from the measured bidirectional delay of the corresponding wireless link.

3. The method according to claim 1, wherein the timing calibration value SL2 of the second sidechain device is calculated as follows: 。 4. The method according to claim 1, wherein the timing calibration value NW of the wireless network node is calculated as follows: 。 5. The method of claim 1, wherein the calculated bidirectional delay is twice the propagation delay between the transmitter and the receiver.

6. The method of claim 1, wherein the measured bidirectional delay is twice the propagation delay between the transmitter and the receiver, the sum of the transmission and reception delays at the transmitter, and the transmission and reception delays at the receiver.

7. The method of claim 1, wherein the calculated bidirectional delay is calculated based on the location of the transmitter and the location of the receiver.

8. The method according to claim 1, further comprising: In determining the timing offset TO of the first wireless link A The timing offset TO of the second wireless link B and the timing offset TO of the third wireless link C Previously, line-of-sight connections were detected on the first wireless link, the second wireless link, and the third wireless link.

9. The method of claim 1, wherein the network node is a network node in the core network, and the method further comprises: Based on the timing calibration values ​​of the base stations, the base stations are prioritized and an ordered list of the base stations is transmitted to the sidechain device to initiate the timing calibration process. and / or A group of base stations is selected based on the timing calibration values ​​of the base stations, and information about the group is transmitted to the sidechain device for clock alignment.

10. The method of claim 1, wherein the network node is the wireless network node, and the method further comprises: Transmit the timing calibration value of the first sidechain device to the first sidechain device; and / or The timing calibration value of the second sidechain device is transmitted to the second sidechain device.

11. The method according to claim 1, further comprising: Using the timing offset TO of the first wireless link A The timing offset TO of the second wireless link B and the timing offset TO of the third wireless link C To calculate the timing calibration value of the wireless network node and the timing calibration value of the second sidechain device.

12. The method according to claim 1, further comprising: A request is transmitted to the first sidechain device to request the first sidechain device to measure the bidirectional delay of the third wireless link; as well as The bidirectional delay of the third wireless link is received from the first sidechain device.

13. A method for communication, comprising: The first sidechain device receives a timing calibration value from the network node, the timing calibration value being based on the timing offset TO of the first wireless link. A Timing offset TO of the second wireless link B Timing offset TO of the third wireless link C The first wireless link is a link between the wireless network node and the first sidechain device, the second wireless link is a link between the wireless network node and the second sidechain device, and the third wireless link is a link between the first sidechain device and the second sidechain device. The network node is either the wireless network node or a network node in the core network. The timing calibration value SL1 of the first sidechain device is calculated as follows: ； as well as The first sidechain device uses the timing calibration value to compensate for transmission and / or reception.

14. The method of claim 13, further comprising: Receive a request from the network node to measure the bidirectional delay of the third wireless link; as well as The measured bidirectional delay of the third wireless link is transmitted to the network node.

15. An apparatus for communication, comprising at least one processing core, at least one memory including computer program code, the at least one memory and the computer program code being configured together with the at least one processing core to cause the apparatus to perform at least the following: Determine the timing offset TO of the first wireless link A The first wireless link is a link between a wireless network node and a first sidechain device, and the timing offset TO of the first wireless link is... A The bidirectional delay calculated based on the first wireless link and the bidirectional delay measured based on the first wireless link, wherein the device is the wireless network node or a network node in the core network. Determine the timing offset TO of the second wireless link B The second wireless link is the link between the wireless network node and the second sidechain device, and the timing offset TO of the second wireless link is... B The bidirectional delay is calculated based on the second wireless link and the bidirectional delay is measured based on the second wireless link; Determine the timing offset TO of the third wireless link C The third wireless link is a link between the first sidechain device and the second sidechain device, and the timing offset TO of the third wireless link is... C The bidirectional delay is calculated based on the third wireless link and the bidirectional delay is measured based on the third wireless link; Using the timing offset TO of the first wireless link A The timing offset TO of the second wireless link B and the timing offset TO of the third wireless link C The timing calibration of the first sidechain device is calculated, wherein the timing calibration value SL1 of the first sidechain device is calculated as follows: Value; and At least the timing calibration value of the first sidechain device is transmitted.

16. The apparatus of claim 15, wherein the at least one memory and the computer program code are further configured, together with the at least one processing core, to cause the apparatus to perform at least the method of any one of claims 2 to 12.

17. An apparatus for communication, comprising at least one processing core, at least one memory including computer program code, said at least one memory and said computer program code being configured together with said at least one processing core to cause the apparatus to perform at least the following: The device receives a timing calibration value from a network node, the timing calibration value being based on a timing offset TO of the first wireless link. A Timing offset TO of the second wireless link B Timing offset TO of the third wireless link C The first wireless link is a link between the wireless network node and the device, the second wireless link is a link between the wireless network node and the second sidechain device, and the third wireless link is a link between the device and the second sidechain device. The network node is either the wireless network node or a network node in the core network. The timing calibration value SL1 of the device is calculated as follows: ;as well as The timing calibration value is used to compensate for the transmission and / or reception of the device.

18. The apparatus of claim 17, wherein the at least one memory and the computer program code are further configured, together with the at least one processing core, to cause the apparatus to perform at least the method of claim 14.

19. An apparatus for communication, comprising: Used to determine the timing offset TO of the first wireless link A The components, wherein the first wireless link is a link between a wireless network node and a first sidechain device, and the timing offset TO of the first wireless link A The bidirectional delay calculated based on the first wireless link and the bidirectional delay measured based on the first wireless link, wherein the device is the wireless network node or a network node in the core network. Used to determine the timing offset TO of the second wireless link B The components, wherein the second wireless link is a link between the wireless network node and the second sidechain device, and the timing offset TO of the second wireless link B The bidirectional delay is calculated based on the second wireless link and the bidirectional delay is measured based on the second wireless link; Used to determine the timing offset TO of the third wireless link C The components, wherein the third wireless link is a link between the first sidechain device and the second sidechain device, and the timing offset TO of the third wireless link C The bidirectional delay is calculated based on the third wireless link and the bidirectional delay is measured based on the third wireless link; The timing offset TO used for using the first wireless link A The timing offset TO of the second wireless link B and the timing offset TO of the third wireless link C A component for calculating the timing calibration value SL1 of the first sidechain device, wherein the timing calibration value SL1 of the first sidechain device is calculated as follows: ； as well as Components for transmitting at least the timing calibration values ​​of the first sidechain device.

20. The apparatus of claim 19, further comprising a component for performing the method of any one of claims 2 to 12.

21. An apparatus for communication, comprising: A component for receiving timing calibration values ​​of the device from a network node, the timing calibration values ​​being based on a timing offset TO of a first wireless link. A Timing offset TO of the second wireless link B Timing offset TO of the third wireless link C The first wireless link is a link between the wireless network node and the device, the second wireless link is a link between the wireless network node and the second sidechain device, and the third wireless link is a link between the device and the second sidechain device. The network node is either the wireless network node or a network node in the core network. The timing calibration value SL1 of the device is calculated as follows: ； as well as Components used to compensate for transmission and / or reception using the timing calibration value.

22. The apparatus of claim 21, further comprising a component for performing the method of claim 14.

23. A non-transitory computer-readable medium having a set of computer-readable instructions stored thereon, which, when executed by at least one processor, causes the apparatus to perform at least the method according to any one of claims 1 to 12 or 13 to 14.

24. A computer program product comprising instructions that, when executed by a device, cause the device to perform the method according to any one of claims 1 to 12 or 13 to 14.

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