Central unit device, user equipment, wireless communication method, and storage medium

Abstract

The present disclosure relates to a central unit (CU) device, user equipment, a wireless communication method, and a storage medium. A CU device according to the present disclosure comprises a processing circuit configured to generate switching configuration information for a user equipment to switch from a source distributed unit (DU) device to a target DU device—the switching configuration information includes one or more candidate target DU devices of the user equipment—and to transmit the switching configuration information to the user equipment. By using the CU device, user equipment, wireless communication method, and storage medium according to the present disclosure, the user equipment can be rapidly switched to a suitable DU device, and the DU device can be rapidly switched to a suitable CU device.

Description

Technology Field

[0001] The present application claims priority to Chinese patent application No. 201910323103.4, titled "CENTRAL UNIT DEVICE, USER EQUIPMENT, WIRELESS COMMUNICATION METHOD, AND STORAGE MEDIUM," filed with the Chinese Intellectual Property Office on April 22, 2019, the entirety of which is incorporated by reference into this specification.

[0002] Technology Field

[0003] The embodiments of the present disclosure generally relate to the field of wireless communication, and in particular to centralized unit equipment, user equipment, wireless communication methods, and computer-readable storage media. More particularly, the present disclosure relates to centralized unit equipment in a wireless communication system, user equipment in a wireless communication system, a wireless communication method performed by centralized unit equipment in a wireless communication system, a wireless communication method performed by user equipment in a wireless communication system, and computer-readable storage media. Background Technology

[0004] In a wireless communication system including a terrestrial network (TN), the gNB-CU (Centralized Unit) serves as an information center and management unit within the gNB's service coverage area. The gNB-CU is responsible for exchanging control information with user equipment within the gNB's service coverage area. The gNB-DU (Distributed Unit) is responsible for exchanging data information with user equipment within the gNB's service coverage area. The gNB-CU and gNB-DU are integrated in the gNB, and the gNB communicates with user equipment.

[0005] In the above wireless communication system, both the CU and the DU are integrated in the gNB. In a wireless communication system where the CU equipment and the DU equipment are separated from each other, there may be cases where user equipment is required to switch from the DU equipment serving the user equipment to a new DU equipment, and cases where the DU equipment is required to switch from the CU equipment serving the DU equipment to a new CU equipment. Therefore, in a wireless communication system where the CU equipment is separated from the DU equipment, a method for rapidly switching user equipment to the appropriate DU equipment and / or a method for rapidly switching DU equipment to the appropriate CU equipment is a technical problem that requires urgent resolution.

[0006] Therefore, it is necessary to provide a technical solution that quickly switches user equipment to appropriate DU equipment and quickly switches DU equipment to appropriate CU equipment.

[0007] The content of the invention provides a general summary of the disclosure rather than the full scope of the disclosure or a comprehensive disclosure of all features.

[0008] The object of the present disclosure is to provide a centralized unit device, user device, wireless communication method, and computer-readable storage medium for switching user device to a suitable DU device and rapidly switching the DU device to a suitable CU device.

[0009] According to an embodiment of the present disclosure, a Centralized Unit (CU) device is provided. Such CU device includes a processing circuit. Such processing circuit is configured to generate switching configuration information for a user device to switch from a source Distributed Unit (DU) device to a target DU device—the switching configuration information includes one or more candidate target DU devices of the user device—and to transmit the switching configuration information to the user device.

[0010] According to an embodiment of the present disclosure, user equipment is provided. This user equipment includes a processing circuit. This processing circuit is configured to receive switching configuration information from a Centralized Unit (CU) equipment—the switching configuration information includes one or more candidate target distributed unit (DU) equipment of the user equipment—and to switch from a source DU equipment to a target DU equipment according to the switching configuration information.

[0011] According to an embodiment of the present disclosure, a wireless communication method performed by a Centralized Unit (CU) device is provided. The method comprises the steps of: generating switching configuration information for a user device to switch from a source Distributed Unit (DU) device to a target DU device—the switching configuration information includes one or more candidate target DU devices of the user device—; and transmitting the switching configuration information to the user device.

[0012] According to an embodiment of the present disclosure, a wireless communication method performed by user equipment is provided. The method comprises the steps of: receiving switching configuration information from a Centralized Unit (CU) device—the switching configuration information includes one or more candidate target distributed unit (DU) devices of the user equipment—; and switching from a source DU device to a target DU device according to the switching configuration information.

[0013] According to another aspect of the present disclosure, a computer-readable storage medium is provided. Such a computer-readable storage medium comprises executable computer instructions that, when executed by a computer, cause the computer to perform a wireless communication method according to the present disclosure.

[0014] According to the present disclosure, a centralized unit device, a user device, a wireless communication method, and a computer-readable storage medium, the CU device generates switching configuration information for switching from a source DU device to a target DU device and transmits such switching configuration information to the user device. Such switching configuration information includes one or more candidate target DU devices. That is, the target DU device to which the user device will switch can be predicted before the user device switches from the source DU device to the target DU device, so the user device can use the switching configuration information to switch to the target DU device and thereby achieve fast switching. Similarly, the CU device may additionally generate switching configuration information for switching from the CU device to the target CU device and transmit such switching configuration information to the source DU device. Such switching configuration information includes a target CU device. That is, the target CU device to which the source DU device will switch can be predicted before the source DU device switches from the CU device to the target CU device, so the source DU device can use the switching configuration information to switch to the target CU device and thereby achieve fast switching.

[0015] Further applicable fields become apparent from the description in this specification. The descriptions and specific examples within the content of the invention are merely illustrative and are not intended to limit the scope of the disclosure. Brief explanation of the drawing

[0016] The drawings described herein are used to illustrate selected embodiments rather than all possible embodiments and are not intended to limit the scope of the disclosure. In these drawings: FIG. 1 is a schematic diagram illustrating a comparison between the architecture of a non-ground network and the architecture of a ground network according to an embodiment of the present disclosure. FIG. 2a is a schematic diagram illustrating the arrangement of CU equipment on a geostationary satellite according to an embodiment of the present disclosure. FIG. 2b is a schematic diagram illustrating the arrangement of CU equipment on a ground base station device according to an embodiment of the present disclosure. FIG. 3 is a block diagram illustrating an example of the configuration of a CU equipment according to an embodiment of the present disclosure. FIG. 4 is a signaling flowchart illustrating a process for predicting a selective target DU equipment by a CU equipment according to an embodiment of the present disclosure. FIG. 5 is a signaling flowchart illustrating a process for predicting a selective target DU equipment by user equipment according to an embodiment of the present disclosure. FIG. 6 is a signaling flowchart illustrating a process of switching from a source DU device to a target DU device by user equipment according to an embodiment of the present disclosure. FIG. 7 is a signaling flowchart illustrating a process of switching from a source DU device to a target DU device by user equipment according to another embodiment of the present disclosure. FIG. 8 is a signaling flowchart illustrating a process of switching user equipment served by source DU equipment according to an embodiment of the present disclosure to a corresponding target DU equipment and switching source DU equipment to a target CU equipment. FIG. 9 is a signaling flowchart of step S804 in FIG. 8 according to an embodiment of the present disclosure. FIG. 10 is a signaling flowchart of step S804 in FIG. 8 according to another embodiment of the present disclosure. FIG. 11 is a signaling flowchart of step S806 in FIG. 8 according to an embodiment of the present disclosure. FIG. 12 is a block diagram illustrating an example of the configuration of user equipment according to an embodiment of the present disclosure. FIG. 13 is a flowchart of a wireless communication method performed by a CU device according to an embodiment of the present disclosure. FIG. 14 is a flowchart of a wireless communication method performed by user equipment according to an embodiment of the present disclosure. FIG. 15 is a block diagram illustrating a first exemplary configuration of an eNB (Evolved Node B). FIG. 16 is a block diagram illustrating a second exemplary configuration of an eNB. FIG. 17 is a block diagram illustrating an exemplary configuration of a smartphone. FIG. 18 is a block diagram illustrating an exemplary configuration of a vehicle navigation device. Although various modifications and substitutions are possible for the present disclosure, specific embodiments are illustrated as examples in the drawings and described in detail herein. However, it should be understood that the description of specific embodiments herein is not intended to limit the present disclosure to the specific form disclosed. Instead, the present disclosure is intended to cover all modifications, equivalents, and substitutions that fall within the spirit and scope of the present disclosure. It should be noted that corresponding reference numbers indicate corresponding components throughout the drawings. Specific details for implementing the invention

[0017] Now, examples of the present disclosure are described more fully with reference to the drawings. The following description is merely illustrative and is not intended to limit the present disclosure and its application or use.

[0018] Exemplary embodiments are provided so that the present disclosure may be fully understood and the scope of the present disclosure may be fully conveyed to those skilled in the art. Examples of various specific details, such as specific components, devices, and methods, are presented to provide a detailed understanding of the embodiments of the present disclosure. Without specific details, exemplary embodiments may be implemented in a number of different forms, none of which is to be construed as limiting the scope of the present disclosure. In some exemplary embodiments, well-known processes, well-known structures, and well-known techniques are not described in detail.

[0019] The present disclosure is described in the following order:

[0020] 1. Description of the Scenario

[0021] 2. Example of Centralized Unit Equipment Configuration

[0022] 3. Example of User Equipment Configuration

[0023] 4. Method Examples

[0024] 5. Application Examples

[0025] <1. Explanation of the Scenario>

[0026] As mentioned above, in wireless communication systems where the CU equipment is separated from the DU equipment, there may be cases where the user equipment is required to switch to a new DU equipment, and cases where the DU equipment is required to switch to a new CU equipment. It is desirable to provide a centralized unit equipment, user equipment, a wireless communication method, and a computer-readable storage medium in accordance with the present disclosure in order to quickly switch the user equipment to a suitable DU equipment and quickly switch the DU equipment to a suitable CU equipment.

[0027] According to embodiments of the present disclosure, a wireless communication system may be a 5G (fifth generation) or 6G (sixth generation) communication system. A wireless communication system provided in the present disclosure may be a satellite communication system including a non-terrestrial network (NTN). Such a satellite communication system may include a plurality of CU equipment, a plurality of DU equipment, and a plurality of user equipment.

[0028] FIG. 1 is a schematic diagram illustrating a comparison between the architecture of a non-terrestrial network and the architecture of a terrestrial network according to an embodiment of the present disclosure. A schematic diagram of the TN architecture is shown on the left portion of FIG. 1, a schematic diagram of the NTN architecture is shown on the right portion of FIG. 1, and 5GC represents the core network of a 5G network. As shown in FIG. 1, in a TN network, a gNB includes one gNB-CU and a plurality of gNB-DUs. The gNB-CU is responsible for transmitting control information to user equipment. The gNB-DU is responsible for transmitting data information to user equipment. Additionally, the gNB-CU can further manage the resources of each gNB-DU.

[0029] In addition, according to an embodiment of the present disclosure, as illustrated in FIG. 1, a plurality of CU devices and a plurality of DU devices are provided in an NTN network. The CU devices are responsible for transmitting control information to user devices. The DU devices are responsible for transmitting data information to user devices. In addition, each CU device can manage the resources of the plurality of DU devices. Here, the CU devices and the DU devices can be separated from each other, that is, they can be arranged in separate devices.

[0030] The Distributed Unit (DU) equipment according to the present disclosure may be a satellite device in a satellite communication system. The DU equipment may be a Low Earth Orbit (LEO) satellite device, a Medium Earth Orbit (MEO) satellite device, a Highly Elliptical Orbiting (HEO) satellite device, and a High Altitude Platform Station (HAPS).

[0031] The Centralized Unit (CU) equipment according to the present disclosure may be a satellite device in a satellite communication system. The CU equipment may be a Geosynchronous Orbit (GEO) satellite device. A GEO satellite device is fixed to ground user equipment and base station devices and has the smallest Doppler shift effect among all types of satellite devices. In addition, a GEO satellite device has relatively large coverage, which facilitates information collection. Therefore, a GEO satellite device is suitable as a CU equipment.

[0032] Additionally, the CU equipment according to the present disclosure may be a ground base station device in a satellite communication system, such as an eNB or a gNB (a base station in a 5th generation communication system). The latency between the ground base station device and the user equipment is small, and the ground base station device is close to the 5G core network. Therefore, the ground base station device can also serve as the CU equipment.

[0033] Additionally, according to an embodiment of the present disclosure, CU equipment may be arranged according to geographical location, that is, one CU equipment to be activated may be arranged in each predetermined area, wherein the predetermined area may be referred to as the service coverage of the activated CU equipment. Optionally, the predetermined area may additionally include one or more CU equipment that is not activated (standby CU equipment). For example, if the CU equipment to be activated fails, one of the standby CU equipment may be activated. Additionally, the service coverage of the CU equipment to be activated may be a spatial service coverage that includes a plurality of DU equipment and a plurality of user equipment. Such spatial service coverage may also be referred to as a VSC (Visual satellite cell).

[0034] FIG. 2a is a schematic diagram illustrating an arrangement of CU equipment on a geostationary satellite according to an embodiment of the present disclosure. As illustrated in FIG. 2a, a satellite communication system may include a plurality of CU equipment, a plurality of DU equipment, and a plurality of UEs. Each of the CU equipment is a GEO satellite device. Each of the DU equipment is a LEO satellite device, an MEO satellite device, an HEO satellite device, or a HAPS. FIG. 2a illustrates the service coverage of each of the CU equipment with dashed boxes. Each of the CU equipment can manage DU equipment and UEs within the service coverage of the CU equipment.

[0035] FIG. 2b is a schematic diagram illustrating an arrangement of CU equipment on a ground base station device according to an embodiment of the present disclosure. As illustrated in FIG. 2b, a satellite communication system may include a plurality of CU equipment, a plurality of DU equipment, and a plurality of UEs. Each of the CU equipment is a ground base station device. Each of the DU equipment is a LEO satellite device or an MEO satellite device, an HEO satellite device, or a HAPS. FIG. 2b illustrates the spatial service coverage of each CU equipment with dashed boxes. Each of the CU equipment can manage DU equipment and UEs within the service coverage of the CU equipment.

[0036] User equipment (UE) according to the present disclosure may be a mobile terminal (such as a smartphone, tablet PC (personal computer), laptop PC, portable gaming terminal, portable / dongle mobile router, and digital camera) or a vehicle terminal (such as a vehicle navigation device). User equipment may be further implemented as a terminal (also referred to as a machine type communication (MTC) terminal) that performs machine-to-machine (M2M) communication. Additionally, user equipment may be a wireless communication module (such as an integrated circuit module comprising a single wafer) mounted on each of the above terminals.

[0037] <2. Example of Centralized Unit Equipment Configuration>

[0038] FIG. 3 is a block diagram illustrating an example of the configuration of a CU equipment (300) according to an embodiment of the present disclosure.

[0039] As illustrated in FIG. 3, the CU equipment (300) may include a generating unit (310) and a communication unit (320).

[0040] Here, the units of the CU equipment (300) may be included in a processing circuit. It should be noted that the CU equipment (300) may include one processing circuit or multiple processing circuits. Additionally, this processing circuit may include various individual functional units to perform various functions and / or operations. It should be noted that these functional units may be physical entities or logical entities, and that units having different names may be implemented by a single physical entity.

[0041] According to embodiments of the present disclosure, the generating unit (310) can generate switching configuration information for a user device to switch from a source DU device to a target DU device. Such switching configuration information includes one or more candidate target DU devices of the user device.

[0042] Here, the user equipment may be within the service coverage of the CU equipment (300). The user equipment is served by the source DU equipment and wants to switch to a new DU equipment.

[0043] According to embodiments of the present disclosure, the communication unit (320) may be configured to receive information from equipment other than the CU equipment (300) and / or transmit information to equipment other than the CU equipment (300). Herein, the CU equipment (300) may transmit switching configuration information to user equipment through the communication unit (320).

[0044] As described above, according to embodiments of the present disclosure, the CU equipment (300) can generate switching configuration information for switching from a source DU equipment to a target DU equipment and transmit such switching configuration information to a user equipment. Such switching configuration information includes one or more candidate target DU equipment. That is, the target DU equipment to be switched to by the user equipment can be predicted before the user equipment switches from the source DU equipment to the target DU equipment, so the user equipment can use the switching configuration information to switch to the target DU equipment, thereby realizing fast switching.

[0045] In the present disclosure, the DU equipment may be a satellite device, and the DU equipment is always in motion. In other words, the DU equipment moves relative to the user equipment. When the DU equipment is a LEO satellite device, the time cycle for the satellite device covering a point on the ground may be only a few minutes, so the user equipment is required to frequently switch the DU equipment serving the user equipment. Clearly, the above description is only one case in which the user equipment is required to switch the DU equipment serving the user equipment, and the conditions for the user equipment to switch from the source DU equipment to the target DU equipment are not limited in the present disclosure. That is, the conditions for the user equipment to switch the DU equipment are similar to the conditions for the user equipment to switch the base station device serving the user equipment in the prior art. For example, if the quality of the link between the user equipment and the DU equipment serving the user equipment degrades, the user equipment may switch from the source DU equipment to the target DU equipment. If the user equipment moves out of the service coverage of the DU equipment serving the user equipment, the user equipment may be switched from the source DU equipment to the target DU equipment. If the movement of the DU equipment serving the user equipment results in the DU equipment being unable to serve the user equipment, the user equipment may be switched from the source DU equipment to the target DU equipment.

[0046] According to embodiments of the present disclosure, the switching configuration information generated by the generating unit (310) may include one or more candidate target DU equipment, for example, the switching configuration information includes identification information of one or more candidate target DU equipment.

[0047] According to embodiments of the present disclosure, the switching configuration information generated by the generating unit (310) may further include priority information of one or more candidate target DU devices of the user equipment. Here, the generating unit (310) may express the priority information in any manner known in the art. For example, the switching configuration information may include identification information and priority information of one or more candidate target DU devices. As another example, the priority information may also be expressed using the order of one or more candidate target DU devices. In an embodiment, one or more candidate target DU devices are ranked and transmitted in descending order of priority.

[0048] According to embodiments of the present disclosure, the CU equipment (300) may additionally transmit switching configuration information to the source DU equipment serving the user equipment via the communication unit (320) so that the source DU equipment establishes a communication link with each of one or more candidate target DU equipment.

[0049] According to embodiments of the present disclosure, switching configuration information transmitted to a source DU equipment by the CU equipment (300) may be the same as switching configuration information transmitted to a user equipment. The CU equipment (300) may transmit switching configuration information to the source DU equipment that includes only identification information of one or more candidate target DU equipment.

[0050] According to embodiments of the present disclosure, after establishing a communication link with each of one or more candidate target DU devices, the source DU device can transmit buffer data that has not been fully transmitted between the source DU device and the user device to each candidate target DU device. In this way, preparations for a subsequent switching process are made so that the user device can quickly switch to the target DU device after the switching conditions are met.

[0051] According to embodiments of the present disclosure, as illustrated in FIG. 3, the CU equipment (300) may further include a determination unit (340). The determination unit (340) is configured to determine a candidate target DU equipment of the user equipment according to the user equipment's optional target DU equipment. Here, the user equipment's optional target DU equipment may be a predicted DU equipment that is highly likely to be switched to by the user equipment. The DU equipment may be predicted by the CU equipment (300) or the user equipment.

[0052] An example of a CU device (300) that predicts the optional target DU device of the user device is described in detail below.

[0053] According to embodiments of the present disclosure, as illustrated in FIG. 3, the CU equipment (300) may further include a prediction unit (330) configured to predict a selective target DU equipment of the user equipment. Additionally, the prediction unit (330) may determine a selective target DU equipment of the user equipment based on at least one of the following information: location information of the user equipment, speed information of the user equipment, link quality information between each DU equipment and the user equipment within the service coverage of the CU equipment (300), and estimated location information of each DU equipment within the service coverage of the CU equipment (300).

[0054] According to embodiments of the present disclosure, the CU equipment (300) may receive a measurement report from the user equipment via a communication unit (320). This measurement report includes link quality information between each DU equipment and the user equipment within the service coverage of the CU equipment (300). Additionally, the CU equipment (300) may further receive location information and / or speed information of the user equipment from the user equipment via the communication unit (320). Here, the user equipment may transmit location information and / or speed information while transmitting the measurement report. Alternatively, the user equipment may transmit the measurement report and the location information and / or speed information at different times. Additionally, the CU equipment (300) may further periodically receive estimated location information from each DU equipment within the service coverage of the CU equipment (300) via the communication unit (320). In this way, the prediction unit (330) obtains at least one of the following information: location information of the user equipment, speed information of the user equipment, link quality information between each DU equipment and the user equipment within the service coverage of the CU equipment (300), and estimated location information of each DU equipment within the service coverage of the CU equipment (300).

[0055] According to embodiments of the present disclosure, the prediction unit (330) can determine the distance between the user equipment and each DU equipment at the moment of switching based on at least one of the following information: location information of the user equipment, speed information of the user equipment, and estimated location information of each DU equipment within the service coverage of the CU equipment (300), and can determine the user equipment's selective target DU equipment based on the distance between the user equipment and each DU equipment. For example, the prediction unit (330) can determine one or more DU equipment close to the user equipment at the moment of switching as selective DU equipment. The prediction unit (330) can further determine the user equipment's selective target DU equipment based on the distance between the user equipment and each DU equipment and the link quality between the user equipment and each DU equipment. For example, the prediction unit (330) can determine the DU equipment close to the user equipment and having good link quality at the moment of switching as selective DU equipment. That is, the prediction unit (330) can predict the DU equipment around the user equipment (optional, having good link quality) at the moment of switching time as the optional DU equipment, i.e., the DU equipment with a high probability of switching to the DU equipment.

[0056] According to embodiments of the present disclosure, as illustrated in FIG. 3, the CU equipment (300) may further include a calculation unit (350) configured to calculate a Doppler frequency shift value between each optional target DU equipment and user equipment. Here, the calculation unit (350) may calculate the Doppler frequency shift value between the DU equipment and user equipment in any manner known in the art, and this is not limited to the present disclosure. Additionally, the switching configuration information generated by the generation unit (310) may further include a Doppler frequency shift value between each candidate target DU equipment and user equipment so that the user equipment performs Doppler compensation for the link between the target DU equipment and user equipment after the user equipment switches from the candidate target DU equipment to the target DU equipment.

[0057] FIG. 4 is a signaling flowchart illustrating CU equipment for predicting optional target DU equipment according to an embodiment of the present disclosure. In FIG. 4, CU may be implemented as CU equipment (300), and UE represents user equipment within the service coverage of CU. As illustrated in FIG. 4, in step S401, the UE transmits a measurement report to the CU, and this measurement report may further include location information of the UE. Optionally, this measurement report may further include velocity information of the UE. Next, in step S402, the CU determines the optional target DU equipment of the UE. Next, in step S403, the CU calculates the Doppler frequency shift value between each optional target DU equipment and the UE. In this way, the CU determines the optional target DU equipment of the UE.

[0058] As described above, the CU equipment (300) according to the embodiments of the present disclosure can predict an optional target DU equipment that the user equipment can switch to. By knowing the estimated location information of each DU equipment within the service coverage of the CU equipment (300), the CU equipment (300) can perform the prediction simply and easily by obtaining location information (optional, and speed information) of the user equipment. Additionally, prior to switching, the optional target DU equipment is predicted and candidate target DU equipment is determined according to the optional target DU equipment to generate switching configuration information, thereby enabling rapid switching of the user equipment.

[0059] An example of user equipment that predicts the optional target DU equipment of user equipment is described in detail below.

[0060] According to embodiments of the present disclosure, the CU equipment (300) may receive a measurement report from the user equipment through a communication unit (320). This measurement report includes link quality information between each DU equipment and the user equipment within the service coverage of the CU equipment.

[0061] Additionally, the CU equipment (300) may transmit estimated location information of a plurality of DU equipment having a link quality higher than a predetermined threshold to the user equipment via the communication unit (320) so that the user equipment determines the user equipment’s optional target DU equipment. According to embodiments of the present disclosure, the measurement report received from the user equipment may further include information indicating that the user equipment wants to predict the user equipment’s optional target DU equipment. For example, such information may be represented by 1 bit, so that the CU equipment (300) may transmit estimated location information of a plurality of DU equipment to the user equipment in response to the information indicating that the user equipment wants to predict the optional target DU equipment.

[0062] Here, the process by which the user equipment determines the optional target DU equipment is similar to the process by which the prediction unit (330) determines the optional target DU equipment. For example, the user equipment may determine the optional target DU equipment of the user equipment based on at least one of the following information: location information of the user equipment, speed information of the user equipment, and estimated location information of a plurality of DU equipment having a link quality higher than a predetermined threshold—estimated location information is received from the CU equipment (300). For example, the user equipment may determine the DU equipment close to the user equipment as the optional DU equipment by determining the distance between each of the plurality of DU equipment having a link quality higher than a predetermined threshold at the moment of switching time between the user equipment and the user equipment. Here, the user equipment selects the optional target DU equipment from the plurality of DU equipment having a link quality higher than a predetermined threshold, and the link quality of the selected optional target DU equipment will be good.

[0063] According to embodiments of the present disclosure, due to a large amount of estimated location information, the CU equipment (300) only transmits estimated location information of multiple DU equipment having a link quality higher than a predetermined threshold to the user equipment. In this way, the information required to be transmitted by the CU equipment can be reduced, and the difficulty and time for the user equipment to select a selective target DU equipment can be reduced.

[0064] According to embodiments of the present disclosure, the CU equipment (300) can receive the user equipment's optional target DU equipment from the user equipment through the communication unit (300). Here, the CU equipment (300) can receive identification information of the user equipment's optional target DU equipment from the user equipment. Additionally, the CU equipment (300) can further receive the Doppler frequency shift value between each optional target DU equipment and the user equipment from the user equipment through the communication unit (300).

[0065] FIG. 5 is a signaling flowchart illustrating user equipment predicting optional target DU equipment according to an embodiment of the present disclosure. In FIG. 5, CU may be implemented by CU equipment (300), and UE represents user equipment within the service coverage of CU. As illustrated in FIG. 5, in step S501, UE transmits a measurement report to CU. This measurement report may further include information indicating that UE wants to predict optional target DU equipment. Next, in step S502, CU transmits estimated location information of a plurality of DU equipment to UE. Next, in step S503, UE determines UE's optional target DU equipment. Next, in step S504, UE calculates the Doppler frequency shift value between each optional target DU equipment and UE. Next, in step S505, UE transmits the optional target DU equipment and the Doppler frequency shift value between each optional target DU equipment and UE to CU. In this way, CU acquires UE's optional target DU equipment.

[0066] As described above, the CU equipment (300) according to the embodiments of the present disclosure obtains the UE’s optional target DU equipment from the UE. Additionally, prior to switching, the optional target DU equipment is predicted and the candidate target DU equipment is determined according to the optional target DU equipment to generate switching configuration information, thereby enabling fast switching of the user equipment.

[0067] According to embodiments of the present disclosure, after the prediction unit (330) of the CU equipment (300) predicts a selective target DU equipment or the CU equipment (300) obtains a selective target DU equipment from the user equipment, the determination unit (340) can determine a candidate target DU equipment based on the selective target DU equipment.

[0068] According to embodiments of the present disclosure, the CU equipment (300) transmits switching request information to each optional target DU equipment via the communication unit (320) and may receive switching response information from the optional target DU equipment indicating whether access by user equipment is permitted. Here, the optional target DU equipment may determine whether access by user equipment is permitted based on the load conditions of the optional target DU equipment and may generate switching response information. For example, the optional target DU equipment may transmit switching response information carrying ACK information to the CU equipment (300) only when access by user equipment is permitted, and may not transmit switching response information in other cases. In such cases, the CU equipment (300) may set a timer, and if switching response information is not received from the optional target DU equipment when the timer expires, it is determined that access by user equipment to the optional target DU equipment is not permitted. As another example, the optional target DU equipment may transmit switching response information carrying ACK information to the CU equipment (300) when access by the user equipment is permitted, and may transmit switching response information carrying NACK information to the CU equipment (300) when access by the user equipment is not permitted. In this case, when the CU equipment (300) receives the switching response information carrying ACK information, it may be determined that the user equipment is permitted to access the optional target DU equipment, and when the CU equipment (300) receives the switching response information carrying NACK information, it may be determined that the user equipment is not permitted to access the optional target DU equipment.

[0069] According to embodiments of the present disclosure, the determination unit (340) may determine candidate target DU equipment for user equipment based on the optional target DU equipment that user equipment is allowed to access. For example, the determination unit (340) may select a predetermined number (preferably three) of optional target DU equipment from the optional target DU equipment that user equipment is allowed to access as candidate target DU equipment. In this way, the amount of switching configuration information may be reduced, thereby reducing the signaling overhead of the CU equipment (300).

[0070] According to embodiments of the present disclosure, the decision unit (340) may further select a candidate target DU device for the user device from among the optional target DU devices that the user device is allowed to access, based on link quality information between the user device and each of the optional target DU devices that the user device is allowed to access. For example, the decision unit (340) may select a predetermined number (preferably three) of optional target DU devices having good link quality from among the optional target DU devices that the user device is allowed to access, as candidate target DU devices. In this case, the decision unit (340) may further determine the priority of the selected candidate target DU devices based on link quality information between the user device and each of the optional target DU devices that the user device is allowed to access. For example, good link quality represents a high priority.

[0071] According to embodiments of the present disclosure, the decision unit (340) may further select candidate target DU equipment for the user equipment from among the optional target DU equipment that the user equipment is allowed to access, based on load information of the optional target DU equipment that the user equipment is allowed to access. For example, the decision unit (340) may select a predetermined number (preferably three) of optional target DU equipment having a light load from among the optional target DU equipment that the user equipment is allowed to access as candidate target DU equipment. In this case, the decision unit (340) may further determine the priority of the selected candidate target DU equipment based on the load information of the optional target DU equipment that the user equipment is allowed to access. For example, a light load represents a high priority.

[0072] According to embodiments of the present disclosure, the decision unit (340) may further select candidate target DU equipment for the user equipment from the optional target DU equipment that the user equipment is allowed to access, based on link quality information between each of the user equipment and the optional target DU equipment that the user equipment is allowed to access, and load information of the optional target DU equipment that the user equipment is allowed to access. For example, the decision unit (340) may select a predetermined number (preferably 3) of optional target DU equipment having good link quality and light load from the optional target DU equipment that the user equipment is allowed to access as candidate target DU equipment. In this case, the decision unit (340) may further determine the priority of the selected candidate target DU equipment based on link quality information between each of the user equipment and the optional target DU equipment that the user equipment is allowed to access, and load information of the optional target DU equipment that the user equipment is allowed to access. For example, good link quality and light load represent high priority.

[0073] In this way, the decision unit (340) can determine the candidate target DU equipment of the user equipment based on the optional target DU equipment of the user equipment. Here, the optional target DU equipment represents the DU equipment most likely to be switched by the user equipment at the moment of switching, and the candidate target DU equipment represents the DU equipment in the optional target DU equipment that the user equipment is allowed to access. Additionally, the decision unit (340) can further filter the DU equipment that the user equipment is allowed to access in order to determine the final candidate target DU equipment.

[0074] According to embodiments of the present disclosure, the CU equipment (300) may additionally transmit a Doppler frequency shift value between the optional target DU equipment and the user equipment to each optional target DU equipment through the communication unit (320) for the target DU equipment at the optional target DU equipment (i.e., the DU equipment that the user eventually switches to) in order to perform Doppler compensation for the link between the target DU equipment and the user equipment after the user equipment switches to the target DU equipment.

[0075] According to embodiments of the present disclosure, the CU equipment (300) may additionally transmit switching duration information to each optional target DU equipment via the communication unit (320) to request the optional target DU equipment to reserve resources for user equipment within the switching duration. For any one of the optional target DU equipment, if no user equipment accesses the optional target DU equipment within the switching duration, the optional target DU equipment may release the reserved resources to avoid wasting resources.

[0076] Here, the CU equipment (300) may transmit Doppler frequency shift values ​​and / or switching duration information while transmitting a switching request to each optional target DU equipment. Alternatively, the CU equipment (300) may transmit the Doppler frequency shift values ​​and / or switching duration information and the switching request at different times.

[0077] As described above, according to embodiments of the present disclosure, the CU equipment (300) can determine candidate target DU equipment from optional target DU equipment and transmit switching configuration information including candidate target DU equipment to user equipment. Preferably, the switching configuration information may further include priority information of candidate target DU equipment. Preferably, when the CU equipment (300) predicts optional target DU equipment and calculates Doppler frequency shift values, the switching configuration information may further include Doppler frequency shift values ​​between each candidate target DU equipment and user equipment.

[0078] Accordingly, examples of switching configuration information include, but are not limited to, the following examples.

[0079]

[0080] FIGS. 6 and FIGS. 7 are signaling flowcharts illustrating user equipment switching from source DU equipment to target DU equipment, respectively, according to an embodiment of the present disclosure. In FIGS. 6 and FIGS. 7, the CU may be implemented by CU equipment (300), and the UE may be within the service coverage of the CU. Additionally, the UE is originally served by the source DU and wishes to switch to a new DU equipment. Here, in FIGS. 6 and FIGS. 7, the CU has predicted or acquired the UE's optional target DU equipment (e.g., through the process illustrated in FIGS. 4 or FIGS. 5). As illustrated in FIGS. 6, in step S601, the CU transmits switching request information to each optional target DU equipment. Alternatively, the CU may additionally transmit switching duration information and / or Doppler frequency shift values ​​to the optional target DU equipment. Next, in step S602, each optional target DU equipment determines whether the UE is allowed to access the DU equipment. Next, in step S603, the optional target DU equipment transmits switching response information to the CU. Here, the switching response information may not be transmitted if the UE is not allowed to access the optional target DU equipment. Next, in step S604, the CU determines the candidate target DU equipment from the optional target DU equipment that the UE is allowed to access. Next, in step S605, the CU generates switching configuration information for the UE and transmits this switching configuration information to the UE and the source DU equipment. This switching configuration information includes at least identification information of the candidate target DU equipment. Next, in step S606, after receiving the switching configuration information, the source DU equipment establishes a link between each candidate target DU equipment and the satellites. In step S607, the source DU equipment transmits buffer data to each candidate target DU equipment.Next, at step S608, the UE determines that the switching condition is satisfied, and the switching is triggered. Next, at step S609, the UE selects a candidate target DU device from one or more candidate target DU devices as the target DU device to which the UE will eventually switch. Next, at step S610, the UE synchronizes with the target DU device. Next, at step S611, the UE switches to the target DU device, and data is transmitted. In this way, the UE switches from the source DU device to the target DU device.

[0081] As illustrated in FIG. 7, in step S701, the CU transmits switching request information to each optional target DU device. Optionally, the CU may additionally transmit switching duration information and / or Doppler frequency shift values ​​to the optional target DU devices. Next, in step S702, each optional target DU device determines whether the UE is allowed to access the optional target DU device. Next, in step S703, the optional target DU device transmits switching response information to the CU. Here, the switching response information may not be transmitted if the UE is not allowed to access the optional target DU device. Next, in step S704, the CU determines candidate target DU devices from the optional target DU devices that the UE is allowed to access. Next, in step S705, the CU generates switching configuration information for the UE and transmits this switching configuration information to the UE and the source DU device. This switching configuration information includes at least identification information of the candidate target DU devices. Next, in step S706, the source DU equipment receives switching configuration information and establishes a link between each candidate target DU equipment and the satellites. In step S707, the source DU equipment transmits buffer data to each candidate target DU equipment. Next, in step S708, until the UE successfully synchronizes with the candidate target DU equipment, the UE may attempt to synchronize with each candidate target DU equipment sequentially (e.g., in descending order of priority), and the candidate target DU equipment is determined as the target DU equipment. Next, in step S709, the UE determines that the switching condition is satisfied, and the switching is triggered. Next, in step S710, the UE switches to the target DU equipment, and data is transmitted. In this way, the UE switches from the source DU equipment to the target DU equipment.

[0082] As described above, in the embodiment illustrated in FIG. 6, after switching is triggered, the UE selects a target DU device from one or more candidate target DU devices, synchronizes with the selected target DU device, and switches from the source DU device to the target DU device. In the embodiment illustrated in FIG. 7, the UE selects a target DU device from one or more candidate target DU devices and synchronizes with the selected target DU device. For example, the UE may attempt to synchronize with each candidate target DU device sequentially (e.g., in descending order of priority) until the UE successfully synchronizes with the candidate target DU device, and the candidate target DU device is determined as the target DU device. After switching is triggered, the UE switches from the source DU device to the target DU device. In this case, the connection between the UE and the source DU device is not interrupted when the UE completes synchronization with the target DU device, so the UE remains in a multi-connection state. In this way, after switching is triggered, the UE can communicate directly with the target DU device, thereby realizing smooth switching. That is, if the UE has multiple-connection capabilities, the process illustrated in FIG. 7 is performed. If the UE does not have multiple-connection capabilities, the process illustrated in FIG. 6 is performed.

[0083] As described above, according to embodiments of the present disclosure, the CU equipment (300) can transmit switching configuration information to the UE to assist the UE in rapidly switching from the source DU equipment to the target DU equipment.

[0084] As described above, the DU equipment may be a satellite device, and the DU equipment is in motion. In other words, the DU equipment moves relative to the user equipment. Particularly when the DU equipment is a LEO satellite device, the time cycle of the satellite device covering a point on the ground may be only a few minutes, so the user equipment is required to frequently switch the DU equipment serving the user equipment. In such cases, the source CU equipment serving the DU equipment may no longer be suitable for serving the DU equipment due to the movement of the DU equipment, so the DU equipment is required to be switched to a new CU equipment, which is explained in detail below.

[0085] According to embodiments of the present disclosure, as illustrated in FIG. 3, the CU equipment (300) may further include a generating unit (360) configured to generate switching configuration information for the source DU equipment to switch from the CU equipment (300) to the target CU equipment. The switching configuration information of the source DU equipment includes the target CU equipment of the source DU equipment. Additionally, the CU equipment (300) may transmit the switching configuration information of the source DU equipment to the source DU equipment through a communication unit (320).

[0086] As described above, according to embodiments of the present disclosure, the CU equipment (300) can generate switching configuration information for the source DU equipment to switch from the CU equipment (300) to the target CU equipment and transmit such switching configuration information to the source DU equipment. In this way, the source DU equipment can switch from the CU equipment (300) to the target CU equipment according to the switching configuration information. Thus, the target CU equipment to which the source DU equipment will switch can be predicted before the source DU equipment switches from the CU equipment (300) to the target CU equipment, thereby realizing fast switching. Additionally, the source DU equipment is required only to periodically report estimated position information without measurement, thereby saving resources and signaling overhead of the source DU equipment.

[0087] According to embodiments of the present disclosure, as illustrated in FIG. 3, the CU equipment (300) further includes a prediction unit (370) configured to determine one or more candidate target CU equipment of the source DU equipment based on the estimated location information of the source DU equipment and the location information of the CU equipment around the source DU equipment. Here, the candidate target CU equipment is a CU equipment predicted by the prediction unit (370) that the source DU equipment is likely to switch to the predicted CU equipment.

[0088] According to embodiments of the present disclosure, the prediction unit (370) may additionally determine a switching time moment when the source DU equipment switches and one or more candidate target CU equipment at such switching time moment, based on the estimated location information of the source DU equipment and the location information of the CU equipment around the source DU equipment.

[0089] Here, the CU equipment (300) can periodically obtain estimated location information from the source DU equipment through the communication unit (320). Additionally, if the CU equipment around the source DU equipment is a satellite device, the CU equipment (300) can obtain estimated location information from the CU equipment around the source DU equipment through the communication unit (320) to obtain location information (optional, velocity information) of the CU equipment around the source DU equipment. If the CU equipment around the source DU equipment is a ground base station device, the CU equipment (300) can obtain location information of the CU equipment around the source DU equipment from the CU equipment around the source DU equipment through the communication unit (320). In this way, the prediction unit (370) obtains at least one of the following information: location information of the source DU equipment, velocity information of the source DU equipment, location information of the CU equipment around the source DU equipment, and velocity information of the CU equipment around the source DU equipment.

[0090] According to embodiments of the present disclosure, the prediction unit (370) determines the distance between the source DU equipment and each CU equipment at each time moment according to at least one of the following information: location information of the source DU equipment, speed information of the source DU equipment, location information of the CU equipment around the source DU equipment, and speed information of the CU equipment around the source DU equipment, and determines the time moment at which the source DU equipment is required to switch at each switching time moment and the candidate target CU equipment of the source DU equipment at that time moment according to the distance between the source DU equipment and each CU equipment. For example, the prediction unit (370) may determine the CU equipment close to the source DU equipment at the switching time moment as the candidate target CU equipment.

[0091] According to embodiments of the present disclosure, as illustrated in FIG. 3, the CU equipment (300) may further include a determination unit (380) configured to determine the target CU equipment of the source DU equipment according to one or more candidate target CU equipment of the source DU equipment. Here, the candidate target CU equipment represents the CU equipment close to the source DU equipment at the moment of switching time, that is, the CU equipment most likely to be switched by the source DU equipment. The target CU equipment represents the CU equipment in the candidate target CU equipment to which the source DU equipment is allowed to access the CU equipment.

[0092] According to embodiments of the present disclosure, the CU equipment (300) transmits switching request information to each of one or more candidate target CU equipment via the communication unit (320) and may receive switching response information from the candidate target CU equipment indicating whether the source DU equipment is allowed to access. Here, the candidate target CU equipment may determine whether to allow the source DU equipment to access based on the load conditions of the candidate target CU equipment and may generate switching response information. For example, the candidate target CU equipment may transmit switching response information carrying ACK information to the CU equipment (300) only when the source DU equipment is allowed to access, and may not transmit switching response information in other cases. In such cases, the CU equipment (300) may set a timer. If the switching response information is not received from the candidate target CU equipment when the timer expires, it is determined that the source DU equipment is not allowed to access the candidate target CU equipment. As another example, the candidate target CU equipment may transmit switching response information carrying ACK information to the CU equipment (300) when access by the source DU equipment is permitted, and may transmit switching response information carrying NACK information to the CU equipment (300) when access by the source DU equipment is not permitted. In this case, when the CU equipment (300) receives the switching response information carrying ACK information, it may be determined that the source DU equipment is permitted to access the candidate target CU equipment, and when the CU equipment (300) receives the switching response information carrying NACK information, it may be determined that the source DU equipment is not permitted to access the candidate target CU equipment.

[0093] According to embodiments of the present disclosure, the determination unit (380) can determine the target CU equipment of the source DU equipment according to the candidate target CU equipment that the source DU equipment is allowed to access. For example, the determination unit (380) can further select a target CU equipment from the candidate target CU equipment that the source DU equipment is allowed to access according to the load information of the candidate target CU equipment that the source DU equipment is allowed to access. For example, the determination unit (380) can select the candidate target CU equipment having the lightest load from the candidate target CU equipment that the source DU equipment is allowed to access as the target CU equipment.

[0094] According to embodiments of the present disclosure, the CU equipment (300) can transmit buffer data regarding the source DU equipment to the target CU equipment through the communication unit (320). In this way, the target CU equipment establishes a link with the source DU equipment to transmit data after receiving the buffer data.

[0095] As described above, according to embodiments of the present disclosure, the CU equipment (300) can assist DU equipment within the service coverage of the CU equipment (300) in switching to a new CU equipment, thereby realizing a fast switching. Here, before the DU equipment switches to a new CU equipment, user equipment served by the DU equipment is required to switch from the DU equipment to the new DU equipment, and this process can be performed with the assistance of the CU equipment (300). Embodiments in which the CU equipment (300) assists user equipment in switching to a target DU equipment are described in detail above, and these embodiments are not repeated herein. Embodiments different from the embodiments described above are described below.

[0096] According to embodiments of the present disclosure, the CU equipment (300) may transmit a forced switching command to the source DU equipment via the communication unit (320), expressing that each user equipment served by the source DU equipment is required to be switched to the target DU equipment. For example, the CU equipment (300) may transmit the forced switching command to the source DU equipment before the switching time moment of the source DU equipment is reached. After receiving the forced switching command, the source DU equipment may generate measurement configuration information for each user equipment to trigger the user equipment to measure the link quality between the user equipment and each DU equipment.

[0097] According to embodiments of the present disclosure, the CU equipment (300) can transmit switching configuration information of the user equipment to each user equipment served by the source DU equipment. The CU equipment (300) can also transmit the switching configuration information of each user equipment served by the source DU equipment to the source DU equipment—the source DU equipment transmits the switching configuration information of each user equipment to the user equipment. Here, the generating unit (310) of the CU equipment (300) is required to generate switching configuration information for each user equipment served by the source DU equipment, and the source DU equipment can transmit the switching configuration information of each user equipment.

[0098] According to embodiments of the present disclosure, the switching configuration information of each user device served by the source DU device generated by the generating unit (310) further includes an effective time for the user device to switch from the source DU device to the target DU device. This effective time represents the maximum time for the user device to complete the switching. After the effective time, the source DU device switches to a new CU device, so that the user device cannot receive information from the CU device (300) and cannot transmit information to the CU device (300) through the source DU device. Therefore, the source DU device performs the switching only by direct communication with the CU device (300).

[0099] FIG. 8 is a signaling flowchart illustrating switching user equipment served by source DU equipment to target DU equipment and switching source DU equipment to target CU equipment according to an embodiment of the present disclosure. In FIG. 8, the source CU may be implemented by CU equipment (300). A UE served by source DU equipment wants to switch from source DU equipment to target DU equipment. Source CU equipment wants to switch from source CU equipment to target CU equipment. As illustrated in FIG. 8, in step S801, source CU equipment obtains location information (and optionally velocity information) of other CU equipment by sharing location information or exchanging estimated location information with other CU equipment around source DU equipment. Next, in step S802, source CU equipment determines the switching time moment of source DU equipment and the candidate target CU equipment of source DU equipment at the switching time moment. Next, in step S803, prior to the switching time moment, the source CU equipment sends a forced switching command to the source DU equipment to switch all UEs served by the source DU equipment to the target DU equipment. Next, in step S804, a selected target DU equipment for each UE is predicted. Next, in step S805, to switch each UE to the target DU equipment, a candidate target DU equipment for each UE is determined, and the target DU equipment is selected from the candidate target DU equipment. Next, in step S806, the source DU equipment switches to the target CU equipment. In this way, each UE served by the source DU equipment switches to the corresponding target DU equipment, and the source DU equipment switches to the target CU equipment.

[0100] FIG. 9 is a signaling flowchart of step S804 in FIG. 8 according to an embodiment of the present disclosure. As illustrated in FIG. 9, in step S901, the source DU equipment transmits measurement configuration information to each UE served by the source DU equipment. Next, in step S902, each UE transmits a measurement report to the source DU equipment. This measurement report includes position information of the UE and optionally includes velocity information of the UE. Next, in step S903, the source DU transmits the measurement reports of all UEs served by the source DU together to the source CU equipment. Next, in step S904, the source CU equipment determines an optional target DU equipment for each UE. Next, in step S905, for each UE, the source CU equipment calculates the Doppler frequency shift value between each optional target DU equipment and the UE. In this way, the source CU equipment determines an optional target DU equipment for each UE. The signaling flowchart shown in FIG. 9 corresponds to the signaling flowchart shown in FIG. 4, except that in FIG. 9, the source DU equipment collects measurement reports from all UEs and transmits these measurement reports to the source CU equipment.

[0101] FIG. 10 is a signaling flowchart of step S804 in FIG. 8 according to another embodiment of the present disclosure. As illustrated in FIG. 10, in step S1001, the source DU transmits measurement configuration information to each UE. Next, in step S1002, each UE transmits a measurement report to the source DU equipment. Next, in step S1003, the source DU transmits all measurement reports of the UE served by the source DU to the source CU equipment. Next, in step S1004, for each UE, the source CU equipment determines a plurality of DU equipment to which the source CU equipment is required to transmit estimated location information. For example, the source CU equipment selects a plurality of DU equipment having a link quality higher than a predetermined threshold and transmits the estimated location information to the source DU equipment. Next, in step S1005, the source DU equipment transmits the estimated location information of the plurality of DU equipment for the UE to each UE. Next, in step S1006, each UE determines an optional target DU device. Next, in step S1007, each UE calculates a Doppler frequency shift value between each optional target DU device and the UE. Next, in step S1008, each UE transmits the optional target DU device determined by the UE and the Doppler frequency shift value corresponding to the UE to the source DU device. Next, in step S1009, the source DU device transmits the optional target DU device for each UE and the Doppler frequency shift value corresponding to the UE to the source CU device. In this way, the source CU device acquires the optional target DU device for each UE.The signaling flowchart illustrated in FIG. 10 corresponds to the signaling flowchart illustrated in FIG. 5, except that in FIG. 10, the source DU equipment collects measurement reports of all UEs and transmits these measurement reports to the source CU equipment, the source CU equipment can transmit estimated position information of multiple DU equipment for each UE to the source CU equipment, and the source DU equipment can collect and transmit Doppler frequency shift values ​​of the optional target DU equipment and each UE.

[0102] It should be noted that FIGS. 9 and 10 illustrate the process of step S804 in FIG. 8 in an exemplary manner. Step S804 in FIG. 8 may also be implemented in the manner illustrated in FIG. 4 or FIG. 5. In other words, the source CU equipment may predict or acquire the optional target DU equipment of each UE with the help of the source DU equipment. Alternatively, the source CU equipment may predict or acquire the optional target DU equipment of each UE by the source CU equipment communicating directly with the UE.

[0103] According to embodiments of the present disclosure, step S805 illustrated in FIG. 8 may be implemented in the manner illustrated in FIG. 6 or FIG. 7, that is, the process of switching the UE to the target DU equipment may be realized as the embodiments described above, which is not repeated herein.

[0104] FIG. 11 is a signaling flowchart of step S806 in FIG. 8 according to an embodiment of the present disclosure. As illustrated in FIG. 11, in step S1101, the source CU equipment transmits switching request information to each candidate target CU equipment. Next, in step S1102, each candidate target CU equipment determines whether to allow the source DU equipment to access the candidate target CU equipment. Next, in step S1103, the candidate target CU equipment transmits a switching response message to the source CU equipment. Here, if the source DU equipment is not allowed to access the candidate target CU equipment, the candidate target CU equipment may not transmit a switching response message to the source CU equipment. Next, in step S1104, the source CU equipment determines the target CU equipment based on the candidate target CU equipment that the source DU equipment is allowed to access. Next, in step S1105, the source CU equipment transmits switching configuration information to the source DU equipment. This switching configuration information includes at least identification information of the target CU equipment. Next, in step S1106, the source CU equipment transmits buffer data to the target CU equipment. Next, in step S1107, the source DU equipment establishes a link with the target CU equipment. Next, in step S1108, data is successfully transmitted between the source DU equipment and the target CU equipment. In this way, the source DU equipment switches from the source CU equipment to the target CU equipment.

[0105] As described above, according to embodiments of the present disclosure, a CU device may generate switching configuration information for switching from a source DU device to a target DU device and transmit such switching configuration information to a user device. Such switching configuration information includes one or more candidate target DU devices. That is, the target DU device to which the user device will switch can be predicted before the user device switches from the source DU device to the target DU device, so the user device can use the switching configuration information to switch to the target DU device and thereby achieve fast switching. Similarly, the CU device may additionally generate switching configuration information for switching from a CU device to a target CU device and transmit such switching configuration information to the source DU device. Such switching configuration information includes a target CU device. That is, the target CU device to which the source DU device will switch can be predicted before the source DU device switches from the CU device to the target CU device, so the source DU device can use the switching configuration information to switch to the target CU device and thereby achieve fast switching. In other words, the CU equipment assists the user equipment in switching from the source DU equipment to the target DU equipment, and can additionally assist the DU equipment in switching to the target CU equipment.

[0106] <3. Example of User Equipment Configuration>

[0107] FIG. 12 is a block diagram of the structure of user equipment (1200) in a wireless communication system according to an embodiment of the present disclosure. As shown in FIG. 12, user equipment (1200) may include a communication unit (1210) and a switching unit (1220).

[0108] Here, the units of the user equipment (1200) may be included in a processing circuit. It should be noted that the user equipment (1200) may include one processing circuit or multiple processing circuits. Additionally, these processing circuits may include various individual functional units to perform various functions and / or operations. It should be noted that these functional units may be physical entities or logical entities, and that units having different names may be implemented by a single physical entity.

[0109] According to embodiments of the present disclosure, user equipment (1200) may transmit information to equipment other than user equipment (1200) and / or receive information from equipment other than user equipment (1200) through a communication unit (1210). For example, user equipment (1200) may receive switching configuration information from CU equipment through the communication unit (1210). Such switching configuration information includes one or more candidate target DU equipment of user equipment (1200). Here, the CU equipment may be CU equipment serving user equipment (1200), that is, user equipment (1200) is within the service coverage of CU equipment.

[0110] According to embodiments of the present disclosure, the switching unit (1220) can switch from the source DU equipment to the target DU equipment according to the switching configuration information.

[0111] As described above, user equipment (1200) according to embodiments of the present disclosure can switch from source DU equipment to target DU equipment according to switching configuration information received from CU equipment. Such switching configuration information includes one or more candidate target DU equipment. That is, before user equipment (1200) switches from source DU equipment to target DU equipment, the target DU equipment that user equipment (1200) can switch to can be predicted, so user equipment (1200) can switch to target DU equipment using the switching configuration information, thereby realizing fast switching.

[0112] According to embodiments of the present disclosure, as illustrated in FIG. 12, the user equipment (1200) may further include a determination unit (1230) configured to determine information regarding one or more candidate target DU equipment by demodulating received switching configuration information. For example, the determination unit (1230) may determine identification information for each of one or more candidate target DU equipment according to the switching configuration information to identify each candidate target DU equipment. Preferably, the determination unit (1230) may determine information for a predetermined number of candidate target DU equipment, for example, information for three candidate target DU equipment, according to the switching configuration information.

[0113] According to embodiments of the present disclosure, the decision unit (1230) may further determine the priority of each of one or more candidate target DU equipment according to switching configuration information. Here, the decision unit (1230) may determine the priority of each candidate target DU equipment according to the order of one or more candidate target DU equipment. For example, candidate target DU equipment arranged in the front rank has a high priority, and candidate target DU equipment arranged in the back rank has a low priority. Optionally, the decision unit (1230) may further determine the priority of each candidate target DU equipment according to the priority information of each candidate target DU equipment included in the switching configuration information. According to embodiments of the present disclosure, the priority information of each candidate target DU equipment represents the evaluation of the candidate target DU equipment performed by the CU equipment, that is, the high priority of the candidate target DU equipment represents that the DU equipment performs a high evaluation of the candidate target DU equipment and that the user equipment (1200) is proposed to switch to the candidate target DU equipment.

[0114] According to embodiments of the present disclosure, the determination unit (1230) may further determine a Doppler frequency shift value between each of one or more candidate target DU equipment and the user equipment (1200) according to switching configuration information. As described above, the CU equipment may determine an optional target DU equipment of the user equipment (1200) and determine a candidate target DU equipment according to this optional target DU equipment. In this case, the CU equipment may calculate a Doppler frequency shift value between each candidate target DU equipment and the user equipment (1200), so that the user equipment (1200) may obtain a Doppler frequency shift value between each candidate target DU equipment and the user equipment (1200) through the switching configuration information.

[0115] According to embodiments of the present disclosure, as illustrated in FIG. 12, the user equipment (1200) may further include a prediction unit (1240) configured to determine a selective target DU equipment of the user equipment (1200) according to at least one of the following information: location information of the user equipment (1200), speed information of the user equipment (1200), and estimated location information of a plurality of DU equipment within the service coverage of the CU equipment.

[0116] According to embodiments of the present disclosure, user equipment (1200) can determine the location of user equipment (1200) and determine the speed of user equipment (1200). Additionally, user equipment (1200) can receive estimated location information of a plurality of DU equipment from CU equipment. Here, the plurality of DU equipment may be some DU equipment having good link quality around user equipment (1200).

[0117] According to embodiments of the present disclosure, as illustrated in FIG. 12, the user equipment (1200) may further include a measurement unit (1250) configured to measure link quality information between each DU equipment and the user equipment (1200) within the service coverage of the CU equipment. This link quality information may be expressed as Reference Signal Receiving Power (RSRP), Reference Signal Receiving Quality (RSRQ), Received Signal Strength Indication (RSSI), etc., but is not limited to those expressed in the present disclosure.

[0118] According to embodiments of the present disclosure, user equipment (1200) may transmit a measurement report to CU equipment via a communication unit (1210). This measurement report includes link quality information between each DU equipment within the service coverage of CU equipment and user equipment (1200). Next, user equipment (1200) receives estimated location information of a plurality of DU equipment having a link quality higher than a predetermined threshold from CU equipment via the communication unit (1210). In this way, user equipment (1200) obtains at least one of the following information to determine a selected target DU equipment of user equipment (1200): location information of user equipment (1200), speed information of user equipment (1200), and estimated location information of a plurality of DU equipment within the service coverage of CU equipment.

[0119] According to embodiments of the present disclosure, when the user equipment (1200) predicts a selective target DU equipment, the measurement report transmitted by the user equipment (1200) to the CU equipment may additionally include information indicating that the user equipment (1200) wants to predict a selective target DU equipment. For example, this information may be represented by 1 bit to cause the CU equipment to transmit estimated location information of a plurality of DU equipment having a link quality higher than a predetermined threshold in response to this information. Additionally, when the CU equipment predicts a selective target DU equipment, the measurement report transmitted by the user equipment (1200) to the CU equipment may additionally include location information of the user equipment (1200) and optionally include speed information of the user equipment (1200) so that the CU equipment predicts the selective target DU equipment of the user equipment (1200). Here, when reporting velocity information, the user equipment (1200) can determine the velocity vector in the coordinate system according to the coordinate system agreed upon with the CU equipment, for example, the ECEF (Earth-Centered, Earth-Fixed) coordinate system. For example, this velocity vector includes velocity components on the x, y, and z axes.

[0120] According to embodiments of the present disclosure, the prediction unit (1240) can determine the distance between the user equipment (1200) and each of the plurality of DU equipment at a switching time moment according to at least one of the following information: location information of the user equipment (1200), speed information of the user equipment (1200), and estimated location information of the plurality of DU equipment within the service coverage of the CU equipment, and can determine the optional target DU equipment of the user equipment (1200) according to the distance between the user equipment (1200) and each DU equipment. For example, the prediction unit (1240) can determine the DU equipment close to the user equipment (1200) at a switching time moment as the optional DU equipment.

[0121] According to embodiments of the present disclosure, the user equipment (1200) may transmit the user equipment (1200)'s optional target DU equipment to the CU equipment via the communication unit (1210) so that the CU equipment determines the user equipment (1200)'s candidate target DU equipment according to the user equipment (1200)'s optional target DU equipment. For example, the user equipment (1200) may transmit identification information of the optional target DU equipment determined by the user equipment (1200) to the CU equipment.

[0122] According to embodiments of the present disclosure, as illustrated in FIG. 12, the user equipment (1200) may further include a calculation unit (1260) configured to calculate a Doppler frequency shift value between each optional target DU equipment and the user equipment (1200). Here, the calculation unit (1260) may calculate the Doppler frequency shift value by any method known in the art, and is not limited to the present disclosure.

[0123] According to embodiments of the present disclosure, whether the user equipment (1200) receives a Doppler frequency shift value between each candidate target DU equipment and the user equipment (1200) from the CU equipment via the communication unit (1210) or calculates a Doppler frequency shift value between each optional target DU equipment and the user equipment (1200) via the calculation unit (1260), the user equipment (1200) may perform Doppler compensation for the link between the target DU equipment and the user equipment (1200) using the Doppler frequency shift value between the target DU equipment and the user equipment (1200) after the target DU equipment that the user equipment (1200) eventually switches to is determined. Compensation in this specification includes uplink compensation and downlink compensation.

[0124] According to embodiments of the present disclosure, the user equipment (1200) may additionally transmit the Doppler frequency shift value between each optional target DU equipment and the user equipment (1200) to the CU equipment via the communication unit (1210) so that the CU equipment transmits the Doppler frequency shift value to the optional target DU equipment. Similarly, after the target DU equipment to which the user equipment (1200) eventually switches is determined, the target DU equipment may perform Doppler compensation on the link between the target DU equipment and the user equipment (1200) according to the Doppler frequency shift value between the target DU equipment and the user equipment (1200). Compensation in this specification includes uplink compensation and downlink compensation.

[0125] As described above, the optional target DU equipment that the user equipment (1200) can switch to can be predicted by the user equipment (1200), and the candidate target DU equipment can be determined by the CU equipment. In this way, the user equipment (1200) determines from the candidate target DU equipment the target DU equipment that the user equipment (1200) will eventually switch to.

[0126] According to embodiments of the present disclosure, as illustrated in FIG. 12, the user equipment (1200) may further include a selection unit (1270) configured to select a target DU equipment that the user equipment (1200) eventually switches from one or more candidate target DU equipment included in the switching configuration information. Here, where priority information for each candidate target DU equipment is not included in the switching configuration information, the selection unit (1270) may randomly select a target DU equipment that the user equipment (1200) eventually switches from one or more candidate target DU equipment, or select a target DU equipment that the user equipment (1200) eventually switches from one or more candidate target DU equipment according to a predetermined rule. When the priority of each candidate target DU equipment is included in the switching configuration information, the selection unit (1270) can select the target DU equipment that the user equipment (1200) eventually switches according to the descending order of priority, that is, the candidate target DU equipment having the highest priority is preferentially selected as the target DU equipment that the user equipment (1200) eventually switches.

[0127] According to embodiments of the present disclosure, after the selection unit (1270) selects a target DU equipment from one or more candidate target DU equipment, the switching unit (1220) can synchronize with the target DU equipment and switch from the source DU equipment to the target DU equipment. Here, if the switching unit (1220) does not successfully synchronize with the target DU equipment selected by the selection unit (1270), the selection unit (1270) can select the target DU equipment again, for example, the selection unit (1270) can randomly select the target DU equipment, select the target DU equipment according to a predetermined rule, or select the target DU equipment in descending order of priority until the switching unit (1220) successfully synchronizes with the target DU equipment.

[0128] In this field, the user equipment may have the capability of multiple connections, that is, the user equipment may simultaneously synchronize with and connect to multiple network-side devices (such as DU equipment). Alternatively, the user equipment may not have the capability of multiple connections, that is, the user equipment may only synchronize with and connect to a single network-side device (such as DU equipment) at any given time. Thus, if the user equipment (1200) has the capability of multiple connections, synchronization may be performed before switching is triggered (i.e., at the switching time moment). If the user equipment (1200) does not have the capability of multiple connections, synchronization may be performed after switching is triggered (i.e., at the switching time moment).

[0129] Accordingly, according to embodiments of the present disclosure, after switching is triggered, the selection unit (1270) can select a target DU equipment from one or more candidate target DU equipment. Next, the switching unit (1220) synchronizes with the selected target DU equipment, and the user equipment (1200) switches from the source DU equipment to the target DU equipment.

[0130] Optionally, according to embodiments of the present disclosure, a selection unit (1270) may select a target DU equipment from one or more candidate target DU equipment, and a switching unit (1220) may synchronize with the selected target DU equipment. Here, the selection unit (1270) may select the target DU equipment in order, so that the switching unit (1220) synchronizes with the target DU equipment in that order until the switching unit (1220) successfully synchronizes with the DU equipment, and the candidate target DU equipment is determined as the target DU equipment that the user equipment eventually switches to. Additionally, after the switching is triggered, the switching unit (1220) may switch the user equipment (1200) from the source DU equipment to the target DU equipment.

[0131] According to embodiments of the present disclosure, the user equipment (1200) can determine the operation of the switching unit (1220) depending on whether the user equipment (1200) has the capability of multiple connections. When the user equipment (1200) has the capability of multiple connections, the connection between the user equipment (1200) and the source DU equipment is not interrupted when the user equipment (1200) completes synchronization with the target DU equipment, so that the user equipment (1200) can communicate directly with the target DU equipment after the switching is triggered, thereby realizing smooth switching.

[0132] The CU equipment (300) according to the embodiments of the present disclosure can serve the user equipment (1200). Accordingly, all embodiments of the CU equipment (300) described above are applicable to the user equipment (1200).

[0133] <Method Example>

[0134] A wireless communication method performed by a CU device (300) in a wireless communication system according to an embodiment of the present disclosure is described in detail below.

[0135] FIG. 13 is a flowchart of a wireless communication method performed by a CU device (300) in a wireless communication system according to an embodiment of the present disclosure.

[0136] As illustrated in FIG. 13, in step S1310, switching configuration information is generated for the user equipment to switch from the source DU equipment to the target DU equipment. This switching configuration information includes one or more candidate target DU equipment of the user equipment.

[0137] Next, in step S1320, this switching configuration information is transmitted to the user equipment.

[0138] Preferably, this switching configuration information further includes priority information of one or more candidate target DU devices of the user equipment.

[0139] Preferably, this wireless communication method further includes the step of transmitting switching configuration information to a source DU equipment serving user equipment—whereby the source DU equipment establishes a communication link with each of one or more candidate target DU equipment.

[0140] Preferably, this wireless communication method further comprises the step of determining a selective target DU equipment of a user equipment according to at least one of the following information: location information of the user equipment, speed information of the user equipment, link quality information between each DU equipment and the user equipment within the service coverage of the CU equipment, and estimated location information of each DU equipment within the service coverage of the CU equipment; and the step of determining a candidate target DU equipment of the user equipment according to the selective target DU equipment of the user equipment.

[0141] Preferably, this wireless communication method further includes the step of calculating a Doppler frequency shift value between each optional target DU equipment and user equipment.

[0142] Preferably, the switching configuration information further includes Doppler frequency shift values ​​between each candidate target DU equipment and user equipment.

[0143] Preferably, this wireless communication method further includes the step of receiving a user equipment's optional target DU equipment from user equipment; and the step of determining a user equipment's candidate target DU equipment according to the user equipment's optional target DU equipment.

[0144] Preferably, this wireless communication method further includes the step of receiving, from user equipment, a Doppler frequency shift value between each optional target DU equipment and user equipment.

[0145] Preferably, this wireless communication method further comprises the steps of: receiving a measurement report from user equipment—the measurement report includes link quality information between each DU equipment and user equipment within the service coverage of CU equipment—and transmitting estimated location information of a plurality of DU equipment having a link quality higher than a predetermined threshold to user equipment—whereby user equipment determines a selective target DU equipment of user equipment.

[0146] Preferably, the measurement report includes information indicating that the user equipment wants to predict the user equipment's optional target DU equipment.

[0147] Preferably, the step of determining candidate target DU equipment of user equipment further includes: transmitting switching configuration information to each optional target DU equipment; receiving switching response information from the optional target DU equipment indicating whether the user equipment is allowed to access it; and determining candidate target DU equipment of user equipment according to the optional target DU equipment to which the user equipment is allowed to access it.

[0148] Preferably, this wireless communication method further includes the step of transmitting switching duration information to each optional target DU equipment to request the optional target DU equipment to reserve resources for user equipment within the switching duration.

[0149] Preferably, the step of determining a candidate target DU equipment for user equipment further includes the step of selecting a candidate target DU equipment for user equipment from the optional target DU equipment that user equipment is allowed to access, based on link quality information between the user equipment and the optional target DU equipment that user equipment is allowed to access, and / or load information of the optional target DU equipment that user equipment is allowed to access.

[0150] Preferably, this wireless communication method further comprises the step of generating switching configuration information for a source DU equipment to switch from a CU equipment to a target CU equipment—the switching configuration information of the source DU equipment includes the target CU equipment of the source DU equipment—; and the step of transmitting the switching configuration information of the source DU equipment to the source DU equipment.

[0151] Preferably, this wireless communication method further includes the step of determining a switching time moment when the source DU equipment switches from the CU equipment to the target CU equipment.

[0152] Preferably, this wireless communication method further comprises the steps of: determining one or more candidate target CU equipment of the source DU equipment and a switching time moment according to the estimated location information of the source DU equipment and the location information of the CU equipment around the source DU equipment; and determining the target CU equipment of the source DU equipment according to the one or more candidate target CU equipment of the source DU equipment.

[0153] Preferably, this wireless communication method further includes the step of receiving location information or estimated location information of a CU equipment around a source DU equipment from a CU equipment around a source DU equipment.

[0154] Preferably, the step of determining the target CU equipment of the source DU equipment further includes: transmitting switching request information to each of one or more candidate target CU equipment; receiving switching response information from the candidate target CU equipment indicating whether the source DU equipment is allowed to access it; and determining the target CU equipment of the source DU equipment according to the candidate target CU equipment that the source DU equipment is allowed to access.

[0155] Preferably, this wireless communication method further includes the step of transmitting buffer data regarding source DU equipment to target CU equipment.

[0156] Preferably, this wireless communication method further includes the step of transmitting a forced switching command to a source DU equipment indicating that each user equipment served by the source DU equipment is required to be switched to a target DU equipment.

[0157] Preferably, the step of transmitting switching configuration information to user equipment further includes the step of transmitting switching configuration information of each user equipment served by the source DU equipment to the source DU equipment—the source DU equipment transmitting switching configuration information of each user equipment to the user equipment.

[0158] Preferably, the switching configuration information of each user device served by the source DU device further includes the effective time for the user device to switch from the source DU device to the target DU device.

[0159] Preferably, the CU equipment is a satellite device in a satellite communication system or a ground base station device in a satellite communication system, and the candidate target DU equipment is a satellite device in a satellite communication system or a high-altitude platform station.

[0160] According to the embodiments of the present disclosure, the above method can be performed by the CU equipment (300) according to the embodiments of the present disclosure. Accordingly, all embodiments of the CU equipment (300) described above are applicable to this method.

[0161] A wireless communication method performed by user equipment (1200) in a wireless communication system according to an embodiment of the present disclosure is described in detail below.

[0162] FIG. 14 is a flowchart of a wireless communication method performed by user equipment (1200) in a wireless communication system according to an embodiment of the present disclosure.

[0163] As illustrated in FIG. 14, in step S1410, switching configuration information is received from CU equipment. This switching configuration information includes one or more candidate target DU (distributed unit) equipment of user equipment.

[0164] Next, in step S1420, the source DU equipment is switched to the target DU equipment according to the switching configuration information.

[0165] Preferably, this wireless communication method further includes the step of determining the priority of each of one or more candidate target DU equipment according to switching configuration information.

[0166] Preferably, this wireless communication method further includes the step of determining a Doppler frequency shift value between each of one or more candidate target DU equipment and user equipment according to switching configuration information.

[0167] Preferably, this wireless communication method further comprises the steps of: determining a selective target DU equipment of a user equipment according to at least one of the following information: location information of the user equipment, speed information of the user equipment, and estimated location information of a plurality of DU equipment within the service coverage of the CU equipment; and transmitting the selective target DU equipment of the user equipment to the CU equipment, wherein the CU equipment determines a candidate target DU equipment of the user equipment according to the selective target DU equipment of the user equipment.

[0168] Preferably, this wireless communication method further comprises the step of transmitting a measurement report to a CU device—the measurement report includes link quality information between each DU device and user device within the service coverage of the CU device—and the step of receiving estimated location information of a plurality of DU devices having a link quality higher than a predetermined threshold from the CU device.

[0169] Preferably, the measurement report includes information indicating that the user equipment wants to predict the user equipment's optional target DU equipment.

[0170] Preferably, this wireless communication method further includes the step of calculating a Doppler frequency shift value between each optional target DU equipment and user equipment; and the step of transmitting the Doppler frequency shift value between each optional target DU equipment and user equipment to CU equipment.

[0171] Preferably, the wireless communication method further comprises the steps of: selecting a target DU equipment from one or more candidate target DU equipment and synchronizing with the selected target DU equipment after switching is triggered; and switching from a source DU equipment to a target DU equipment.

[0172] Preferably, this wireless communication method further comprises the steps of: selecting a target DU device from one or more candidate target DU devices and synchronizing with the selected target DU device; and switching from a source DU device to a target DU device after the switching is triggered.

[0173] Preferably, the CU equipment is a satellite device in a satellite communication system or a ground base station device in a satellite communication system, and the candidate target DU equipment is a satellite device in a satellite communication system or a high-altitude platform station.

[0174] According to the embodiments of the present disclosure, the above method can be performed by user equipment (1200) according to the embodiments of the present disclosure. Accordingly, all embodiments of the user equipment (1200) described above are applicable to this method.

[0175] <5. Application Example>

[0176] The technology according to the present disclosure may be applicable to various products.

[0177] The ground base station device may be implemented as any type of base station device, such as a macro eNB and a small eNB. The ground base station device may also be implemented as any type of gNB (base station in a 5G system). A small eNB may be an eNB of a cell having a smaller coverage than a macro cell, such as a pico eNB, a micro eNB, and a home (femto) eNB. Alternatively, the base station may be implemented as any other type of base station, such as a NodeB and a BTS (base transceiver station). The base station may include a main body (also referred to as a base station device) configured to control radio communication; and one or more RRHs (remote radio heads) arranged at locations different from the main body.

[0178] User equipment may be implemented as a mobile terminal (such as a smartphone, tablet PC (personal computer), laptop PC, portable gaming terminal, portable / dongle mobile router, and digital camera) or as a vehicle terminal (such as a vehicle navigation device). User equipment may also be implemented as a terminal that performs machine-to-machine (M2M) communication (also referred to as a machine-type communication (MTC) terminal). Additionally, user equipment may be a wireless communication module (such as an integrated circuit module comprising a single wafer) mounted on each of the above user equipment.

[0179] <Example of Base Station Application>

[0180] (First Application Example)

[0181] FIG. 15 is a block diagram illustrating a first exemplary configuration of an eNB to which the technology according to the present disclosure may be applied. The eNB (1500) includes one or more antennas (1510) and base station devices (1520). Each of the antennas (1510) is connected to the base station device (1520) via an RF cable.

[0182] Each of the antennas (1510) comprises a single antenna element or multiple antenna elements (such as multiple antenna elements included in a MIMO (multiple-input multiple-output) antenna) and is used by a base station device (1520) to transmit and receive radio signals. The eNB (1500) may include multiple antennas (1510), as illustrated in FIG. 15. For example, the multiple antennas (1510) may be compatible with multiple frequency bands used by the eNB (1500). Although FIG. 15 illustrates an example in which the eNB (1500) includes multiple antennas (1510), the eNB (1500) may also include a single antenna (1510).

[0183] The base station device (1520) includes a controller (1521), a memory (1522), a network interface (1523), and a wireless communication interface (1525).

[0184] The controller (1521) may be, for example, a CPU or a DSP and may operate various functions of the upper layer of the base station device (1520). For example, the controller (1521) may generate a data packet based on data in a signal processed by a wireless communication interface (1525) and transmit the generated packet through a network interface (1523). The controller (1521) may generate a bundled packet by bundling data from multiple baseband processors and transmit the generated bundled packet. The controller (1521) may have logic functions that perform control such as wireless resource control, wireless bearer control, mobility management, acknowledgment control, and scheduling. Control may be performed in combination with a nearby eNB or core network node. The memory (1522) includes RAM and ROM and stores programs executed by the controller (1521) and various types of control data (such as terminal lists, transmit power data, and scheduling data).

[0185] The network interface (1523) is a communication interface through which the base station device (1520) is connected to the core network (1524). The controller (1521) can communicate with the core network node or another eNB through the network interface (1523). In this case, the eNB (1500) can be connected to the core network node or another eNB through a logical interface (such as interface S1 and interface X2). The network interface (1523) may also be a wired communication interface or a wireless communication interface for a wireless backhaul line. If the network interface (1523) is a wireless communication interface, the network interface (1823) may use a frequency band for wireless communication higher than the frequency band used by the wireless communication interface (1525).

[0186] The wireless communication interface (1525) supports any cellular communication scheme (such as LTE (long term evolution) and LTE-Advanced) and provides wireless access to a terminal located in a cell of the eNB (1500) via an antenna (1510). The wireless communication interface (1525) may include, for example, a base band (BB) processor (1526) and an RF circuit (1527). The BB processor (1526) may perform signal processing of various types of layers (such as encoding / decoding, modulation / demodulation and multiplexing / de-multiplexing, and L1, medium access control (MAC), radio link control (RLC), and packet data convergence protocol (PDCP)). Instead of the controller (1521), the BB processor (1526) may have some or all of the above logic functions. The BB processor (1526) may be implemented as a module comprising a memory for storing a communication control program, or a processor configured to execute the program and related circuitry. The function of the BB processor (1526) may be changed by updating the program. This module may be a card or blade inserted into a slot of the base station device (1520). Alternatively, this module may be a chip mounted on the card or blade. Additionally, the RF circuitry (1527) may include, for example, a mixer, a filter, or an amplifier, and transmits and receives wireless signals through the antenna (1510).

[0187] As illustrated in FIG. 15, the wireless communication interface (1525) may include a plurality of BB processors (1526). For example, the plurality of BB processors (1526) may be compatible with a plurality of frequency bands used by the eNB (1500). As illustrated in FIG. 15, the wireless communication interface (1525) may include a plurality of RF circuits (1527). For example, the plurality of RF circuits (1527) may be compatible with a plurality of antenna elements. Although FIG. 15 illustrates an example in which the wireless communication interface (1525) includes a plurality of BB processors (1526) and a plurality of RF circuits (1527), the wireless communication interface (1525) may include a single BB processor (1526) or a single RF circuit (1527).

[0188] (2nd Application Example)

[0189] FIG. 16 is a block diagram illustrating a second exemplary configuration of an eNB to which the technology of the present disclosure may be applied. The eNB (1630) includes one or more antennas (1640), a base station device (1650), and an RRH (1660). The RRH (1660) may be connected to each of the antennas (1640) via an RF cable. The base station device (1650) may be connected to the RRH (1660) via a high-speed line, such as a fiber optic cable.

[0190] Each of the antennas (1640) comprises a single antenna element or multiple antenna elements (such as multiple antenna elements included in a MIMO antenna) and is used by the RRH (1660) to transmit and receive radio signals. As illustrated in FIG. 16, the eNB (1630) may include multiple antennas (1640). For example, the multiple antennas (1640) may be compatible with multiple frequency bands used by the eNB (1930). Although FIG. 16 illustrates an example where the eNB (1630) includes multiple antennas (1640), the eNB (1630) may also include a single antenna (1640).

[0191] The base station device (1650) includes a controller (1651), a memory (1652), a network interface (1653), a wireless communication interface (1655), and a connection interface (1657). The controller (1651), the memory (1652), and the network interface (1653) are identical to the controller (1521), the memory (1522), and the network interface (1523) described with reference to FIG. 15, respectively.

[0192] The wireless communication interface (1655) supports any cellular communication scheme (such as LTE and LTE-Advanced) and provides wireless communication with a terminal located in a sector corresponding to the RRH (1660) via the RRH (1660) and antenna (1640). The wireless communication interface (1655) may generally include, for example, a BB processor (1656). Except that the BB processor (1656) is connected to the RF circuit (1664) of the RRH (1660) via a connection interface (1657), the BB processor (1656) is identical to the BB processor (1526) described with reference to FIG. 15. The wireless communication interface (1655) may include a plurality of BB processors (1656), as shown in FIG. 16. For example, multiple BB processors (1656) may be compatible with multiple frequency bands used by the eNB (1630). Although FIG. 16 illustrates an example in which the wireless communication interface (1655) includes multiple BB processors (1656), the wireless communication interface (1655) may also include a single BB processor (1656).

[0193] The connection interface (1657) is an interface for connecting a base station device (1650) (wireless communication interface (1655)) to the RRH (1660). The connection interface (1657) may also be a communication module for communication on the high-speed line connecting the base station device (1650) (wireless communication interface (1655)) to the RRH (1660).

[0194] The RRH (1660) includes a connection interface (1661) and a wireless communication interface (1663).

[0195] The connection interface (1661) is an interface for connecting the RRH (1660) (wireless communication interface (1663)) to the base station device (1650). The connection interface (1661) may also be a communication module for communication on the aforementioned high-speed line.

[0196] A wireless communication interface (1663) transmits and receives wireless signals through an antenna (1640). The wireless communication interface (1663) may generally include, for example, an RF circuit (1664). The RF circuit (1664) may include, for example, a mixer, a filter, and an amplifier, and transmits and receives wireless signals through the antenna (1640). The wireless communication interface (1663) may include a plurality of RF circuits (1664), as illustrated in FIG. 16. For example, the plurality of RF circuits (1664) may support a plurality of antenna elements. Although FIG. 16 illustrates an example in which the wireless communication interface (1663) includes a plurality of RF circuits (1664), the wireless communication interface (1663) may also include a single RF circuit (1664).

[0197] In the eNB (1500) and eNB (1630) illustrated in FIG. 15 and FIG. 16, respectively, the generation unit (310), prediction unit (330), decision unit (340), calculation unit (340), generation unit (360), prediction unit (370), and decision unit (380) illustrated in FIG. 3 may be implemented by the controller (1521) and / or the controller (1651). At least some of the functions may also be implemented by the controller (1521) and the controller (1651). For example, the controller (1521) and / or the controller (1651) can generate switching configuration information for the user equipment, predict optional target DU equipment for the user equipment, determine candidate target DU equipment for the user equipment, calculate Doppler frequency shift values ​​between the user equipment and the DU equipment, generate switching configuration information for the DU equipment, predict candidate target CU equipment for the DU equipment, and determine the target CU equipment for the DU equipment by executing instructions stored in memory.

[0198] <Example of application to terminal devices>

[0199] (First Application Example)

[0200] FIG. 17 is a block diagram illustrating an exemplary configuration of a smartphone (1700) to which the technology according to the present disclosure may be applied. The smartphone (1700) includes a processor (1701), memory (1702), storage device (1703), external connection interface (1704), camera (1706), sensor (1707), microphone (1708), input device (1709), display device (1710), loudspeaker (1711), wireless communication interface (1712), one or more antenna switches (1715), one or more antennas (1716), a bus (1717), a battery (1718), and an auxiliary controller (1719).

[0201] The processor (1701) may be, for example, a CPU or a system on chip (SoC) and controls the functions of the application layer and other layers of the smartphone (1700). The memory (1702) includes RAM and ROM and stores data and programs executed by the processor (1701). The storage device (1703) may include a storage medium such as semiconductor memory and a hard disk. The external connection interface (1704) is an interface for connecting external devices (such as memory cards and USB (universal serial bus) devices) to the smartphone (1700).

[0202] The camera (1706) includes an image sensor such as a CCD (charge coupled device) and a CMOS (complementary metal oxide semiconductor) and generates a captured image. The sensor (1707) may include a group of sensors such as a measurement sensor, a gyroscope sensor, a geomagnetic sensor, and an accelerometer sensor. The microphone (1708) converts sound input to the smartphone (1700) into an audio signal. The input device (1709) includes, for example, a touch sensor, a keypad, a keyboard, a button, or a switch configured to detect a touch on the screen of the display device (1710) and receives actions or information input from the user. The display device (1710) includes a screen (such as an LCD (liquid crystal display) and an OLED (organic light-emitting diode) display) and displays an output image of the smartphone (1700). The loudspeaker (1711) is configured to convert an audio signal output from the smartphone (1700) into sound.

[0203] The wireless communication interface (1712) supports any cellular communication scheme (such as LTE and LTE-Advanced) and performs wireless communication. The wireless communication interface (1712) may include, for example, a BB processor (1713) and an RF circuit (1714). The BB processor (1713) may perform, for example, coding / decoding, modulation / demodulation and multiplexing / de-multiplexing, and perform various types of signal processing for wireless communication. The RF circuit (1714) may include, for example, a mixer, a filter and an amplifier, and transmits and receives wireless signals through an antenna (1716). The wireless communication interface (1712) may be a chip module in which the BB processor (1713) and the RF circuit (1714) are integrated. As illustrated in FIG. 17, the wireless communication interface (1712) may include a plurality of BB processors (1713) and a plurality of RF circuits (1714). Although FIG. 17 illustrates an example in which the wireless communication interface (1712) includes a plurality of BB processors (1713) and a plurality of RF circuits (1714), the wireless communication interface (1712) may include a single BB processor (1713) or a single RF circuit (1714).

[0204] In addition to cellular communication schemes, the wireless communication interface (1712) may support additional types of wireless communication schemes, such as short-range wireless communication schemes, near-field communication schemes, and wireless LAN (local area network) schemes. In such cases, the wireless communication interface (1712) may include a BB processor (1713) and an RF circuit (1714) for each wireless communication scheme.

[0205] Each of the antenna switches (1715) switches the connection destination of the antenna (1716) among a number of circuits (such as circuits for different wireless communication schemes) included in the wireless communication interface (1712).

[0206] Each of the antennas (1716) comprises a single antenna element or multiple antenna elements (such as multiple antenna elements included in a MIMO antenna), and a wireless communication interface (1712) is used to transmit and receive wireless signals. A smartphone (1700) may include multiple antennas (1716), as illustrated in FIG. 17. Although FIG. 17 illustrates an example in which the smartphone (1700) includes multiple antennas (1716), the smartphone (1700) may also include a single antenna (1716).

[0207] Additionally, the smartphone (1700) may include an antenna (1716) for each type of wireless communication scheme. In this case, the antenna switches (1715) may be omitted from the configuration of the smartphone (1700).

[0208] A processor (1701), memory (1702), storage device (1703), external access interface (1704), camera (1706), sensor (1707), microphone (1708), input device (1709), display device (1710), loudspeaker (1711), wireless communication interface (1712), and auxiliary controller (1719) are connected to each other via a bus (1717). A battery (1718) supplies power to the blocks of the smartphone (1700) shown in FIG. 17 through feeders partially shown by dotted lines in the drawing. The auxiliary controller (1719) operates the minimum necessary functions of the smartphone (1700), for example, in sleep mode.

[0209] In the smartphone (1700) illustrated in FIG. 17, the switching unit (1220), determination unit (1230), prediction unit (1240), measurement unit (1250), calculation unit (1260), and selection unit (1270) illustrated in FIG. 12 may be implemented by a processor (1701) or an auxiliary controller (1719). At least some of the functions may also be implemented by the processor (1701) or the auxiliary controller (1719). For example, the processor (1701) or the auxiliary controller (1719) may switch from a source DU equipment to a target DU equipment, determine a candidate target DU equipment, predict a selected target DU equipment, measure link quality, calculate a Doppler frequency shift value, and select a target DU equipment by executing instructions stored in memory (1702) or a storage device (1703).

[0210] (2nd Application Example)

[0211] FIG. 18 is a block diagram illustrating an exemplary configuration of a vehicle navigation device (1820) to which the technology according to the present disclosure may be applied. The vehicle navigation device (1820) includes a processor (1821), memory (1822), a GPS (global positioning system) module (1824), a sensor (1825), a data interface (1826), a content player (1827), a storage media interface (1828), an input device (1829), a display device (1830), a loudspeaker (1831), a wireless communication interface (1833), one or more antenna switches (1836), one or more antennas (1837), and a battery (1838).

[0212] The processor (1821) may be, for example, a CPU or an SoC and controls the navigation function and other functions of the vehicle navigation device (1820). The memory (1822) includes RAM and ROM and stores programs and data executed by the processor (1821).

[0213] The GPS module (1824) calculates the location of the vehicle navigation device (1820) (such as latitude, longitude, and altitude) using GPS signals received from GPS satellites. The sensor (1825) may include a group of sensors such as a gyroscope sensor, a geomagnetic sensor, and an air pressure sensor. The data interface (1826) is connected to the vehicle network (1841) via, for example, a terminal not shown, and acquires data (such as vehicle speed data) generated by the vehicle.

[0214] The content player (1827) plays content stored on a storage medium (such as a CD and DVD) inserted into the storage medium interface (1828). The input device (1829) includes, for example, a touch sensor, a button, or a switch configured to detect a touch on the screen of the display device (1830) and receives actions or information input by the user. The display device (1830) includes a screen such as an LCD or OLED display and displays a navigation function or an image of the played content. The loudspeaker (1831) outputs the sound of the navigation function or the played content.

[0215] The wireless communication interface (1833) supports any cellular communication scheme (such as LTE and LTE-Advanced) and performs wireless communication. The wireless communication interface (1833) may generally include, for example, a BB processor (1834) and an RF circuit (1835). The BB processor (1834) may perform, for example, encoding / decoding, modulation / demodulation, and multiplexing / de-multiplexing, and perform various types of signal processing for wireless communication. Additionally, the RF circuit (1835) may include, for example, a mixer, a filter, and an amplifier, and transmits and receives wireless signals through an antenna (1837). The wireless communication interface (1833) may also be a chip module in which the BB processor (1834) and the RF circuit (1835) are integrated. The wireless communication interface (1833) may include a plurality of BB processors (1834) and a plurality of RF circuits (1835), as illustrated in FIG. 18. Although FIG. 18 illustrates an example in which the wireless communication interface (1833) includes a plurality of BB processors (1834) and a plurality of RF circuits (1835), the wireless communication interface (1833) may include a single BB processor (1834) or a single RF circuit (1835).

[0216] In addition to the cellular communication scheme, the wireless communication interface (1833) may support other types of wireless communication schemes, such as short-range wireless communication schemes, near-field communication schemes, and wireless LAN schemes. In such cases, the wireless communication interface (1833) may include a BB processor (1834) and an RF circuit (1835) for each wireless communication scheme.

[0217] Each of the antenna switches (1836) switches the connection destination of the antenna (1837) among a number of circuits (such as circuits for different wireless communication schemes) included in the wireless communication interface (1833).

[0218] Each of the antennas (1837) comprises a single antenna element or multiple antenna elements (such as multiple antenna elements included in a MIMO antenna), and a wireless communication interface (1833) is used to transmit and receive wireless signals. A vehicle navigation device (1820) may include multiple antennas (1837), as illustrated in FIG. 18. Although FIG. 18 illustrates an example in which the vehicle navigation device (1820) includes multiple antennas (1837), the vehicle navigation device (1820) may include a single antenna (1837).

[0219] Additionally, the vehicle navigation device (1820) may include an antenna (1837) for each wireless communication scheme. In such a case, antenna switches (1836) may be omitted from the configuration of the vehicle navigation device (1820).

[0220] The battery (1838) supplies power to the blocks of the vehicle navigation device (1820) shown in FIG. 18 through feeders partially shown by dotted lines in FIG. 18. The battery (1838) accumulates power supplied from the vehicle.

[0221] In the vehicle navigation device (1820) illustrated in FIG. 18, the switching unit (1220), determination unit (1230), prediction unit (1240), measurement unit (1250), calculation unit (1260), and selection unit (1270) illustrated in FIG. 12 may be implemented by a processor (1821). At least some of the functions may also be implemented by the processor (1821). For example, the processor (1821) may switch from a source DU device to a target DU device, determine a candidate target DU device, predict a selected target DU device, measure link quality, calculate a Doppler frequency shift value, and select a target DU device by executing instructions stored in memory (1822).

[0222] The technology of the present disclosure may also be implemented as a vehicle system (or vehicle) (1840) comprising one or more blocks in a vehicle navigation device (1820), a vehicle network (1841), and a vehicle module (1842). The vehicle module (1842) generates vehicle data (such as vehicle speed, engine speed, and fault information) and outputs the generated data to the vehicle network (1841).

[0223] Preferred embodiments of the present disclosure have been described above with reference to the drawings. However, the present disclosure is not limited to the examples above. Those skilled in the art may make various modifications and changes within the scope of the appended claims. It should be understood that such modifications and changes fall within the technical scope of the present disclosure.

[0224] For example, units shown as dashed blocks in the functional block diagrams illustrated in the drawings are optional in the corresponding device. Additionally, optional functional units can be combined in a manner suitable for achieving the required functions.

[0225] For example, in the above embodiments, multiple functions included in a single unit may be achieved by separate devices. Alternatively, in the above embodiments, multiple functions achieved by multiple units may be achieved by separate devices. Additionally, one of the above functions may be achieved by multiple units. Such configurations should be included within the technical scope of the present disclosure.

[0226] In this specification, the steps described in the flowcharts include not only processing performed in a time series in the described order, but also processing performed in parallel or individually instead of in a time series. Additionally, the steps performed in a time series may be performed in a different order.

[0227] Although embodiments of the present disclosure have been described in detail above with reference to the drawings, it should be understood that the embodiments described above are not intended to limit the present disclosure but are used merely to illustrate the present disclosure. Those skilled in the art may make various modifications and variations to the embodiments described above without departing from the essence and scope of the present disclosure. Accordingly, the scope of the present disclosure is defined only by the appended claims and their equivalents.

Claims

Claim 1 A CU (Centralized Unit) device comprising a processing circuit, wherein the processing circuit is configured to generate switching configuration information for a user device to switch from a source DU (Distributed Unit) device to a target DU device, wherein the switching configuration information of the user device includes one or more candidate target DU devices of the user device; to transmit the switching configuration information of the user device to the user device; to generate switching configuration information for the source DU device to switch from the CU device to a target CU device, wherein the switching configuration information of the source DU device includes a target CU device of the source DU device; and to transmit the switching configuration information of the source DU device to the source DU device. Claim 2 In claim 1, the processing circuit is further configured to transmit switching configuration information of the user equipment to a source DU equipment serving the user equipment—whereby the source DU equipment establishes a communication link with each of the one or more candidate target DU equipment. Claim 3 A CU device configured, wherein the processing circuit further determines a selective target DU device of the user device according to at least one of the following information: location information of the user device, speed information of the user device, link quality information between each DU device within the service coverage of the CU device and the user device, and estimated location information of each DU device within the service coverage of the CU device; and determines a candidate target DU device of the user device according to the selective target DU device of the user device. Claim 4 In paragraph 3, the processing circuit is further configured to calculate a Doppler frequency shift value between each optional target DU equipment and the user equipment, and the switching configuration information of the user equipment further includes a CU equipment comprising a Doppler frequency shift value between each candidate target DU equipment and the user equipment. Claim 5 In claim 1, the processing circuit is further configured to receive, from the user equipment, an optional target DU equipment of the user equipment; and to determine a candidate target DU equipment of the user equipment according to the optional target DU equipment of the user equipment. Claim 6 In paragraph 5, the processing circuit further comprises: receiving a measurement report from the user equipment—the measurement report comprising link quality information between each DU equipment within the service coverage of the CU equipment and the user equipment—and transmitting to the user equipment estimated location information of a plurality of DU equipment having a link quality higher than a predetermined threshold—the user equipment determining a selective target DU equipment of the user equipment. Claim 7 In paragraph 3, the processing circuit is further configured to transmit switching request information to each optional target DU equipment; to receive switching response information from the optional target DU equipment indicating whether the user equipment is allowed to access; and to determine the candidate target DU equipment of the user equipment according to the optional target DU equipment to which the user equipment is allowed to access. Claim 8 In claim 7, the processing circuit is further configured to transmit switching duration information to each optional target DU equipment to request the optional target DU equipment to reserve resources for the user equipment within the switching duration. Claim 9 In claim 7, the processing circuit is further configured to select a candidate target DU equipment of the user equipment from the optional target DU equipment that the user equipment is allowed to access, according to at least one of link quality information between the user equipment and the optional target DU equipment that the user equipment is allowed to access, and load information of the optional target DU equipment that the user equipment is allowed to access. Claim 10 delete Claim 11 In claim 1, the processing circuit is additionally configured to determine a switching time moment when the source DU equipment switches from the CU equipment to the target CU equipment. Claim 12 In claim 11, the processing circuit is further configured to determine one or more candidate target CU equipment of the source DU equipment and the switching time moment according to the estimated location information of the source DU equipment and the location information of the CU equipment around the source DU equipment; and to determine the target CU equipment of the source DU equipment according to the one or more candidate target CU equipment of the source DU equipment. Claim 13 In claim 12, the processing circuit is further configured to transmit switching request information to each of the one or more candidate target CU equipment; to receive switching response information from the candidate target CU equipment indicating whether the source DU equipment is allowed to access it; and to determine the target CU equipment of the source DU equipment according to the candidate target CU equipment that the source DU equipment is allowed to access. Claim 14 In claim 1, the processing circuit is further configured to transmit a forced switching command to the source DU equipment expressing that each user equipment served by the source DU equipment is required to be switched to a corresponding target DU equipment. Claim 15 A system comprising CU equipment and user equipment according to claim 1, wherein the user equipment comprises a processing circuit, and the processing circuit is configured to receive switching configuration information of the user equipment from a CU (Centralized Unit) equipment, wherein the switching configuration information of the user equipment includes one or more candidate target DU (distributed unit) equipment of the user equipment; and to switch from a source DU equipment to a target DU equipment according to the switching configuration information of the user equipment. Claim 16 A system configured such that, in paragraph 15, the processing circuit further determines a selective target DU equipment of the user equipment according to at least one of the following information: location information of the user equipment, speed information of the user equipment, and estimated location information of a plurality of DU equipment within the service coverage of the CU equipment; and transmits the selective target DU equipment of the user equipment to the CU equipment—whereby the CU equipment determines a candidate target DU equipment of the user equipment according to the selective target DU equipment of the user equipment. Claim 17 In paragraph 16, the processing circuit is further configured to transmit a measurement report to the CU equipment—the measurement report includes link quality information between each DU equipment within the service coverage of the CU equipment and the user equipment—and to receive from the CU equipment estimated location information of a plurality of DU equipment having a link quality higher than a predetermined threshold value. Claim 18 A system according to claim 15, wherein the processing circuit is further configured to select a target DU equipment from one or more candidate target DU equipment and synchronize with the selected target DU equipment after switching is triggered; and to switch from the source DU equipment to the target DU equipment. Claim 19 A system according to claim 15, wherein the processing circuit further comprises selecting a target DU equipment from one or more candidate target DU equipment and synchronizing with the selected target DU equipment; and switching from the source DU equipment to the target DU equipment after the switching is triggered. Claim 20 A wireless communication method performed by a Centralized Unit (CU) device, comprising: a step of generating switching configuration information for switching from a source Distributed Unit (DU) device to a target DU device by a user device, wherein the switching configuration information of the user device includes one or more candidate target DU devices of the user device; a step of transmitting the switching configuration information of the user device to the user device; a step of generating switching configuration information for switching from a CU device to a target CU device by a source DU device, wherein the switching configuration information of the source DU device includes a target CU device of the source DU device; and a step of transmitting the switching configuration information of the source DU device to the source DU device. Claim 21 delete Claim 22 delete Claim 23 delete Claim 24 delete Claim 25 delete Claim 26 delete Claim 27 delete Claim 28 delete Claim 29 delete Claim 30 delete Claim 31 delete Claim 32 delete Claim 33 delete Claim 34 delete Claim 35 delete Claim 36 delete Claim 37 delete Claim 38 delete Claim 39 delete Claim 40 delete Claim 41 delete Claim 42 delete Claim 43 delete Claim 44 delete Claim 45 delete Claim 46 delete Claim 47 delete Claim 48 delete Claim 49 delete Claim 50 delete Claim 51 delete Claim 52 delete Claim 53 delete Claim 54 delete Claim 55 delete Claim 56 delete Claim 57 delete Claim 58 delete Claim 59 delete Claim 60 delete Claim 61 delete Claim 62 delete Claim 63 delete Claim 64 delete Claim 65 delete Claim 66 delete Claim 67 delete

Images