UE logging during handover

Abstract

A method for use by a communication device, the method comprising the following steps: receiving (S30) a handover HO command from a service network cell among a plurality of network cells, the service network cell providing communication services for the communication device; acquiring (S31) current handover related information; recording (S33) current handover related information only when a predetermined condition is met (S32), wherein the predetermined condition is a condition that the current handover related information is different from previous handover related information, wherein the previous handover related information is acquired and reported by the communication device before receiving the HO command.

Description

Technical Field

[0001] At least some example embodiments relate to mobility in cellular and mobile communication systems such as Long Term Evolution (LTE) or New Radio (NR). In particular, at least some example embodiments relate to so-called "Conditional Handover" (CHO), which aims to improve mobility robustness in combination with the use of multiple beams.

[0002] List of abbreviations / acronyms:

[0003] 3GPP Third Generation Partnership Project

[0004] BS Base Station

[0005] CHO Condition Switch

[0006] gNB Next Generation NodeB

[0007] HO Handover

[0008] LTE Long Term Evolution

[0009] NR New Radio

[0010] OFDM Orthogonal Frequency Division Multiplexing

[0011] RACH Random Access Channel

[0012] RRC Radio Resource Control

[0013] UE User Equipment

[0014] Xn gNB to gNB interface, as defined in 3GPP TS38.423 Background Art

[0015] In the case where a mobile terminal, such as a user equipment (UE) (hereinafter also referred to as a "communication device"), is assigned within a (cellular) communication network to a serving node (or "cell") that is currently serving the mobile terminal and / or associated with the mobile terminal, a handover (HO) to another node (or "cell") will be performed, which then serves the terminal under handover conditions. A typical handover condition occurs if the mobile terminal moves across the geographical coverage of the corresponding node within the cellular communication network. However, the same geographical coverage may be served by multiple nodes or cells, and in such a scenario, handover conditions may also occur. For example, a (single) node may define different cells (which may be distinguished, for example, by different physical resources associated therewith), and thus a handover may occur at the same node, but be a handover from cell to cell. Various handover procedures are known, and one of them is a conditional handover (CHO).

[0016] Condition HO(CHO):

[0017] The CHO procedure is similar to a conventional handover. The message sequence diagram for a (typical and known) CHO scenario is shown in Figure 1 Shown in.

[0018] The entities involved in the signaling are illustrated in a horizontal arrangement as a terminal or user equipment (UE) for which a handover or conditional handover CHO is (to be) performed, a source gNB (currently serving / associated with the UE) and a target gNB (subsequently serving / associated with the UE). The source gNB and the target gNB communicate via an interface Xn (not illustrated as such). The messages exchanged between such entities are illustrated as arrows and the actions / processing of the messages at the entities are illustrated as boxes / circles. The temporal sequence of the messages is "top-down" in the figures.

[0019] The first steps (represented by S1 to S8 in “Phase 1”) are largely identical to conventional handovers. The source gNB performs measurement control of the UE (S1). A configuration event (S2) triggers the UE to send a measurement report to the serving gNB (S3). Based on the report, the source gNB typically prepares the target gNB for handover (handover request from the source gNB to the target gNB in ​​S4) and receives (from the target gNB in ​​S5) a handover request confirmation and then sends a handover command to the UE (S6). The command includes a list of cells or typically resources prepared for the handover. In step S7, the target gNB prepares the corresponding reservation of the resources (cells) confirmed in S5 and in step S8, the UE confirms the HO command to the source gNB.

[0020] For conventional HO, the UE will immediately access the target cell / target gNB to complete the handover. In contrast, for CHO, the UE will only access the target gNB once the additional CHO execution condition expires. This condition is typically configured by the source gNB during the HO command in S6, for example.

[0021] The advantage of CHO is that the HO command (in S6) can be sent very early in the so-called preparation phase (phase 1) when the UE is still safe in the source cell, without risking access in the target cell and the stability of its radio link.

[0022] The HO Command is generated by the target cell and included in the Handover Request Confirm before the source forwards it to the UE via Radio Resource Control (RRC) signaling.

[0023] The "actual" HO is performed in the CHO execution phase (phase 2, see steps S9 to S13). After the CHO execution conditions are met (i.e., a CHO execution event occurs), see S9, the UE performs synchronization and random access with / towards the target gNB in ​​step S10. Thereafter, a Handover Complete message is sent from the UE to the target gNB in ​​S11 and the target gNB acknowledges this in a Handover Complete Acknowledge message to the source gNB in ​​step S12. In the subsequent step / phase S13, the UE and the source gNB will adapt to the extent that the "old" (i.e., previous) preparations or settings are no longer valid for them. Therefore, after the (HO or) CHO is completed, the target gNB will become the new source gNB.

[0024] In CHO, since there may be a significant time delay between HO preparation and the actual HO execution, the situation at the target cell may change during this time.

[0025] In addition, if Figure 1 As shown, after receiving the handover command, the UE does not immediately perform the handover to the target cell, but waits until the CHO execution condition is met, which may take some time. Therefore, the information that the source cell has about the UE at the preparation time (such as, for example, beam / cell measurement values, UE position and speed, related neighboring cells, the last serving beam from the source cell, etc.) may become outdated at the moment when the UE performs the handover to the target cell.

[0026] This uncertainty makes it unclear to record handover statistics. Handover statistics are currently used in many places for network optimization, such as for tracking area optimization, for interference coordination, for load balancing, for tilt optimization, etc. In CHO, there is still a unique source cell and a unique target cell, but neither the source cell nor the target cell can record the exact beam boundary where the handover was finally performed.

[0027] For example, the source does not know the beam of the target cell to which the UE ultimately performs handover, and the target does not know the last serving beam in the source cell.

[0028] Therefore, neither the source cell nor the target cell can record handover statistics on the cell and / or beam level, and therefore any network optimization on the cell and / or beam level is not possible without improving the recording of handover statistics.

[0029] The problem is Figure 2The black dots indicate base stations, different colors (grey, dark grey and light grey) indicate the dominant areas of different cells, and different shades indicate the dominant areas of different beams. The UE moves from the source cell (dark grey) to the target cell (light grey) and performs CHO. When, for example, the UE is in beam 1 and has reported to the source cell that beam 8 of the target cell is the strongest, the source cell can prepare and configure CHO to the target cell at an early stage. However, CHO is only performed when the CHO execution condition expires, and at this point in time, the UE has already proceeded to beam 3 of the source cell, and beam 5 of the target cell is likely to be the strongest, and is therefore selected for random access channel (RACH) access and CHO is completed.

[0030] However, the only thing is that the handover takes place between the source cell and the target cell. However, between which beams it is not clear, in detail:

[0031] • The source cell does not know which beam the UE has been shown in (in this example this would be beam 5). It knows that beam 3 is the last serving beam. It also knows that it has prepared beam 8 while the UE was in beam 1.

[0032] The target cell does not know the last serving beam of the source cell (in this example it would be beam 3). It may not even know the serving beam during preparation (beam 1). It knows the prepared beam (beam 8) and the beam actually accessed (beam 5).

[0033] • The "real" handover boundary is the source cell beam 3 / target cell beam 5 pair, which is not known by either the source cell or the target cell.

[0034] • The "prepared" handover boundary between source cell beam 1 / target cell beam 8 is known to the source. However, this information may be misleading.

[0035] • For completeness, note that a source cell beam 1 / target cell beam 5 pair would confuse any network optimization, so purely updating the HO statistics with the real accessed beam (which could be done by the target cell) is not an option.

[0036] It has been disclosed for NR regular handover for Release 15 that the UE can record beam measurements of the serving cell and neighboring cells at the moment the UE performs RACH access to the target cell. This can help the source cell identify whether the available information about the UE has changed since the transmission of the handover command.

[0037] However, due to the short duration between handover preparation and execution in conventional handover, the information recorded by the UE when handover is executed may be the same as the information reported before receiving the handover command in many cases. Thus, UE recording and reporting will be invalid in these cases.

[0038] In conditional handover, the duration T that elapses between receiving the handover command and execution may vary for each target cell depending on radio conditions, speed of the UE, etc.

[0039] Applying the recording method of the related art to conditional switching may also result in unnecessary information recording and reporting if the elapsed duration T is small or the radio conditions have not changed much at the CHO execution time. Summary of the invention

[0040] It is an object of at least some example embodiments to improve upon the prior art.

[0041] This object is achieved by the method, the device and the non-transitory storage medium specified in the appended claims.

[0042] Further, there is provided a computer program product comprising computer executable code which, when executed by a processor, performs the method according to any method aspect.

[0043] At least some example embodiments are provided for reducing unnecessary UE logging and reporting to the network in both normal and conditional handover scenarios.

[0044] According to at least some example embodiments, at least one of the following advantages is achieved:

[0045] The UE does not have to log unnecessary information which consumes radio resources for reporting.

[0046] No processing energy is wasted since the UE does not have to log unnecessary information.

[0047] Ultimately, this supports and improves user quality of experience due to improved service continuity.

[0048] Other advantages will become apparent from the detailed description that follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Other details, features, objects and advantages will be apparent from the following detailed description of example embodiments of at least some aspects taken in conjunction with the accompanying drawings, in which:

[0050] Figure 1 A signaling diagram illustrating the CHO preparation and execution procedure is shown.

[0051] Figure 2 An example of uncertainty in the current beam usage of the handover statistics caused by the mobility of the UE during CHO is shown.

[0052] Figure 3A flow chart illustrating an example method according to at least some embodiments is shown.

[0053] Figure 4 A flow chart illustrating an example method according to at least some embodiments is shown.

[0054] Figure 5 Signaling diagrams illustrating examples of HO preparation procedures and obtaining, logging, and exchanging HO related information according to at least some example embodiments are shown.

[0055] Figure 6 A signaling diagram is shown according to at least some example embodiments, wherein CHO execution is initiated before a certain duration T has elapsed since a HO was received.

[0056] Figure 7 A signaling diagram is shown according to at least some example embodiments, wherein the UE initiates a CHO execution after a certain duration T has elapsed since receiving the HO.

[0057] Figure 8 A schematic block diagram illustrating a configuration of a control unit in which at least some example embodiments may be implemented is shown. DETAILED DESCRIPTION

[0058] In the following, certain aspects are illustrated by at least some embodiments described in detail with reference to the accompanying drawings. The features of the example embodiments can be freely combined with each other unless otherwise described. However, it is to be clearly understood that the description of certain example embodiments / aspects is given by way of example only and is not intended to be understood as limiting the application to the disclosed details.

[0059] It is to be understood that any modifications mentioned may be applied individually or in combination to the respective aspects to which they relate, unless they are explicitly stated to exclude alternatives.

[0060] Furthermore, it is to be understood that the apparatus is configured to perform the corresponding method, although in some cases only the apparatus or only the method is described.

[0061] According to at least some example embodiments, a communication device (also referred to as a "user equipment (UE)") receives a handover (HO) command from a serving network cell among a plurality of network cells. When the communication device receives the HO command, the communication device begins to acquire current handover related information. If a predetermined condition is met, the communication device records the current handover related information.

[0062] exist Figure 3 , method 1 according to at least some example embodiments is illustrated.

[0063] In S30 of method 1, the communication device receives a HO command from a serving network cell among multiple cells of the communication network. The serving cell provides communication services for the communication device. Subsequently, in S31, the communication device obtains current handover related information. In S32, it is checked whether a predetermined condition is met. In S32, if it is "yes", the current handover related information is recorded in S33. Otherwise (in S32, if it is "no"), the method ends without recording the current handover related information. It should be noted that the current handover related information refers to specific information (hereinafter also referred to as information Y) that is recorded and reported only when the predetermined condition is met.

[0064] In at least some example embodiments, when HO is performed under at least one of the following conditions, the source cell instructs the UE to record and report new HO related information at that moment (e.g., information about the UE's beam and / or cell measurements, UE location and speed, related neighbor cells, the last serving beam from the source cell, etc.):

[0065] (1) If the measured value has a configurable difference from the last reported measured value before the HO command was received, i.e., the radio conditions and the measured value have changed significantly.

[0066] (2) If at least one beam and / or cell measurement value of the target cell or other neighboring cells (including the previous serving cell) differs from at least one beam and / or cell measurement value previously reported by at least a certain threshold, for example, a difference of + / -Q1dB.

[0067] (3) If the UE detects at least one new beam and / or cell measurement of a neighboring cell (including the serving cell) that was not previously reported, such as a beam measurement value above the threshold T1, or a neighboring cell measurement value that is Q2 dB stronger than the source cell.

[0068] (4) If the serving beam has changed since the HO command message was received.

[0069] (5) If at least a certain duration T has elapsed since the HO command was received. Note that this condition is more relevant to CHO.

[0070] According to at least some example embodiments, the predetermined condition checked in S32 is a condition that the current handover related information is different from the previous handover related information, wherein the previous handover related information is acquired and reported by the communication device before receiving the HO command. In other words, the predetermined condition includes at least one of the conditions (1) to (4) indicated above.

[0071] Alternatively or additionally, the predetermined condition checked in S32 is the condition that at least a certain duration T has elapsed since the receipt of the handover command before initiating execution of the conditional handover CHO. In other words, the predetermined condition includes the condition (5) indicated above.

[0072] In at least some example embodiments, after a handover command is received, or after a handover command is received and if predefined handover conditions for HO execution are met, the HO execution is initiated.

[0073] In at least some example embodiments, for both conventional HO and CHO, the time for handover execution is defined by the time for sending the RACH preamble (Message 1).

[0074] In at least some example embodiments, for CHO, the time for handover execution is defined as the time when the CHO condition is satisfied.

[0075] Furthermore, in at least some example embodiments, the at least one specific duration is derived from at least one of a system information parameter and / or information related to the handover command.

[0076] Furthermore, according to at least some example embodiments, at least one specific duration is scaled by a mobility state of the communication device.

[0077] Additionally, in at least some example embodiments, the at least one specific duration is given in terms of at least one of seconds, milliseconds, number of elapsed radio frames, subframes, time slots, and / or orthogonal frequency division multiplexing (OFDM) symbols.

[0078] In addition, in at least some example embodiments, after a random access channel (RACH) access between a communication device and a target network cell is performed, an indication of the availability of recorded current switching related information is transmitted to a target network cell providing communication services among multiple network cells (also referred to as 'other network cells among multiple network cells' hereinafter).

[0079] Additionally, in at least some example embodiments, a request to report the recorded current handover related information is received from the target network cell upon sending an indication of availability of the recorded current handover related information to the target network cell.

[0080] Furthermore, in at least some example embodiments, after the UE receives a request to report the recorded current handover related information from the target network cell, the recorded current handover related information is transmitted to the target network cell.

[0081] Furthermore, in at least some example embodiments, the transmission of the recorded current handover related information is performed directly after or during completion of the handover execution.

[0082] exist Figure 4 In the method 2 according to at least some example embodiments, a method 2 is illustrated. In S40, a serving network cell serving a UE (hereinafter also referred to as a 'communication device') among a plurality of network cells transmits a HO command to the UE to switch the UE to a target network cell (hereinafter also referred to as 'another network cell among a plurality of network cells') (S40). The HO command includes a predetermined condition when the current handover related information will be recorded. The method then ends.

[0083] In at least some exemplary embodiments, the predetermined condition is the same as described above with respect to method 1.

[0084] Figure 5 A signaling diagram is shown that illustrates an example of a HO preparation procedure and obtaining, recording, and exchanging HO related information according to at least some example embodiments. Figure 1 , the entities involved in the signaling are illustrated in a horizontal arrangement as a user equipment (UE) for which a handover or conditional HO is (to be) performed, a serving BS (e.g., a source gNB, BS currently serving / associated with the UE), and a target BS (e.g., a target gNB, BS subsequently serving / associated with the UE). The serving BS and the target BS communicate via an interface Xn (not illustrated as such). The messages exchanged between such entities are illustrated as arrows, and the actions / processing of the messages at the entities are illustrated as boxes / circles. The temporal sequence of the messages is "top-down" in the figure.

[0085] At the beginning of the relevant process, the serving BS (source cell) sends a measurement control message to the UE (S510). Then, the UE sends a measurement report to the source cell (S511), which triggers a HO request from the source cell to the target BS (target cell) (S512). The request is confirmed by a HO request confirmation from the target cell to the source cell (S513). Thereafter, the source cell issues a HO command to the UE (S514). The HO command includes information instructing the UE to record and report current HO related information only when a predetermined condition is met. Figure 5In the example implementation shown, in the case where the measured value is different from the measured value reported before the HO command is received (for example, in the case where the current HO related information is different from the previous HO related information reported before the HO command is received), the predetermined condition is met. After receiving the HO command, the UE initiates HO execution (S515). Then, if the current HO related information is different from the information already reported before the HO command is received, the UE records the current HO related information (S516). Otherwise, it does nothing. Next, RACH access occurs and the HO is completed (S517). In subsequent steps, the UE transmits an indication of the availability of the recorded current HO related information to the target cell (S518). The target cell signals its interest in the information by requesting the reporting of the currently recorded HO related information (S519), and the UE sends the information accordingly (S520). Finally, the target cell forwards the currently recorded HO related information to the source cell for further use (S521).

[0086] Understandably, Figure 3 and Figure 4 The steps are also reflected in Figure 5 In the example procedure of . Receiving / sending the HO command in step S30 / S40 corresponds to step S514, in which the source cell issues a HO command to the UE. In steps S31, S32 and S33, if the predetermined conditions are met, the current HO related information is obtained and recorded, which is also in Figure 5 In the example embodiment of , the method is performed in steps S515 and S516.

[0087] Figure 6 and Figure 7 A signaling diagram illustrating a procedure according to at least some example embodiments is shown, wherein the predetermined condition is a condition that at least one certain duration T has elapsed since a handover command was received before initiating CHO execution. Figure 6 The case where CHO execution is initiated before a certain duration T has elapsed since the HO was received is illustrated. Figure 1 and 5 , the entities involved in the signaling are illustrated in a horizontal arrangement as a user equipment (UE) for which a handover or conditional HO is (to be) performed, a serving BS (e.g., a source gNB, BS currently serving / associated with the UE), and a target BS (e.g., a target gNB, BS subsequently serving / associated with the UE). The serving BS and the target BS communicate via an interface Xn (not illustrated as such). The messages exchanged between such entities are illustrated as arrows, and the actions / processing of the messages at the entities are illustrated as boxes / circles. The temporal sequence of the messages is "top-down" in the figure.

[0088] At the beginning of the relevant process, the serving BS (source cell) sends a measurement control message to the UE (S610). Then, the UE sends a measurement report to the source cell (S611), which triggers a HO request from the source cell to the target BS (target cell) (S612). The request is confirmed by a HO request confirmation (S613) from the target cell to the source cell. Thereafter, the source cell issues a HO command to the UE (S614). The HO command includes information instructing the UE to record and report the current HO related information only when the CHO execution is initiated after a specific duration T. In step S615, the CHO execution is initiated before the specific duration T has passed. Next, RACH access occurs and the HO is completed (S616). However, since the CHO execution is initiated before the specific duration has passed, the current HO related information is not recorded and reported (S617).

[0089] Understandably, Figure 3 and 4 The steps are also reflected in Figure 6 In the example procedure of . Receiving / transmitting the HO command in step S30 / S40 corresponds to step S614, in which the source cell issues a HO command to the UE. In steps S31, S32 and S33, if the predetermined conditions are met, the current HO related information is obtained and recorded. However, in Figure 6 In the example embodiment of FIG. 5 , the predetermined condition is not satisfied, and therefore, the current HO related information is not reported to the target network cell ( S617 ).

[0090] Figure 7 A case is shown where the UE initiates CHO execution after a certain duration T has elapsed since receiving the HO. Figure 7 Steps S710 to S714 correspond to Figure 6 The steps S610 to S614 are described below, and therefore descriptions of these steps are omitted.

[0091] In step S715, CHO execution is initiated after a specific duration T has passed, and the UE records the current HO related information. Next, RACH access occurs and HO is completed (S716). In a subsequent step, the UE sends an indication to the target cell about the availability of the recorded current information (S717). According to an example embodiment, the information includes handover related information X (here the elapsed duration T) required by the network and reported by the UE regardless of the predetermined condition, and handover related information Y (here the elapsed duration (from the receipt of the HO command) exceeds the duration T) reported only when the predetermined condition is met. In this example embodiment, the handover related information Y is Figure 3The target cell signals its interest in the currently recorded HO related information by requesting reporting of the currently recorded HO related information (S718), and the UE sends the information accordingly (S719). Finally, the target cell forwards the currently recorded HO related information to the source cell for further use (S720).

[0092] Understandably, Figure 3 and 4 The steps are also reflected in Figure 7 In the example procedure of . Receiving / sending the HO command in step S30 / S40 corresponds to step S714, in which the source cell issues a HO command to the UE. In steps S31, S32 and S33, if the predetermined conditions are met, the current handover related information is obtained and recorded. These steps are also reflected in Figure 7 In step S715.

[0093] Figure 8 Control units 10, 20 and 30 are depicted, including processing resources (e.g., processing circuit systems) 11, 21, 31, memory resources (e.g., memory circuit systems) 12, 22, 32 and interfaces (e.g., interface circuit systems) 13, 23, 33, respectively. In at least one exemplary embodiment, the control unit 10 is configured to be ... Figure 5 , 6 7 and UE) is implemented and / or used by it, the control unit 20 is configured to serve the BS (eg Figure 5 , 6 7 and the source cell and / or serving BS) and / or used by it, and the control unit 30 is configured to Figure 5 , 6 7 and 7 (target cells and / or target BS) are implemented and / or used by them. Further, each control unit has its own bus system 14, 24, 34, which connects the above resources so that data can be exchanged between the three components of the unit. In addition, the control units 10 and 20 and the control units 10 and 30 can be connected wirelessly via links 41, 42. The control unit 20 and the control unit 30 also have an additional Xn interface 40, which realizes the connection between the corresponding units and their resources.

[0094] The terms "connected," "coupled," or any variations thereof, refer to any connection or coupling, direct or indirect, between two or more elements, and may encompass the presence of one or more intermediate elements between two elements being "connected" or "coupled" together. The coupling or connection between elements may be physical, logical, or a combination thereof. As employed herein, two elements may be considered to be "connected" or "coupled" together through the use of one or more wires, cables, and printed electrical connections, and through the use of electromagnetic energy, such as, without limitation, electromagnetic energy having wavelengths in the radio frequency region, microwave region, and optical (visible and invisible) region.

[0095] The definitions indicated in this description are based on current 3GPP standards. However, they are not restrictive. Other definitions based on the same or corresponding concepts are also applicable to some example embodiments.

[0096] A piece of information can be transmitted from one entity to another in one or more messages. Each of these messages can include other (different) information.

[0097] The names of network elements, protocols and methods are based on current standards. In other versions or other technologies, the names of these network elements and / or protocols and / or methods may be different, as long as they provide corresponding functionality.

[0098] If not stated otherwise or otherwise apparent from the context, a statement that two entities are different means that they perform different functions. It does not necessarily mean that they are based on different hardware. That is, each of the entities described in this description may be based on different hardware, or some or all of the entities may be based on the same hardware. It does not necessarily mean that they are based on different software. That is, each of the entities described in this description may be based on different software, or some or all of the entities may be based on the same software. Each of the entities described in this description may be implemented in the cloud.

[0099] Based on the above description, it should be apparent that the example embodiments provide, for example, a base station such as a gNB or a component thereof, an apparatus implementing the base station, a method for controlling and / or operating the base station, and (multiple) computer programs for controlling and / or operating the base station, as well as a medium that carries (multiple) such computer programs and forms (multiple) computer program products.

[0100] In general, various embodiments of a UE may include, but are not limited to, a mobile station, a cellular telephone, a personal digital assistant (PDA) with wireless communication capabilities, a portable computer with wireless communication capabilities, an image capture device with wireless communication capabilities (such as a digital camera), a gaming device with wireless communication capabilities, a music storage and playback device with wireless communication capabilities, an Internet device that allows wireless Internet access and browsing, and a portable unit or terminal that incorporates a combination of such functionality.

[0101] As non-limiting examples, implementation of any of the above blocks, apparatus, systems, techniques or methods includes implementation as hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controllers or other computing devices, or some combination thereof.

[0102] Further, as used in this application, the term "circuitry" refers to one or more or all of the following:

[0103] (a) hardware circuit implementation only (such as implementation only in analog and / or digital circuitry); and

[0104] (b) a combination of circuitry and software (and / or firmware), such as (where applicable): (i) a combination of processor(s); or (ii) portions of processor(s) / software (including digital signal processor(s), software and memory(s) that work together to enable a device such as a mobile phone or server to perform various functions) and

[0105] (c) Circuitry that requires software or firmware to operate, such as microprocessor(s) or portion(s) of microprocessor(s), even if the software or firmware is not physically present.

[0106] This definition of "circuitry" applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term "circuitry" would also cover an implementation of only a processor (or multiple processors) or a portion of a processor and its (or their) accompanying software and / or firmware. For example, and if applicable to the particular claim element, the term "circuitry" would also cover a baseband integrated circuit or an application processor integrated circuit for a mobile phone or similar integrated circuit in a server, cellular network device, or other network device.

[0107] According to at least some example embodiments, an apparatus for use by a communication device is provided. For example, the apparatus includes Figure 8 The control unit 10 is shown. According to another exemplary embodiment or in addition, the device is configured to perform Figure 3 Method 1 is shown.

[0108] The device includes: a component for receiving a handover HO command from a service network cell providing communication services for a communication device among multiple network cells; a component for acquiring current handover related information; and a component for recording current handover related information only when a predetermined condition is met.

[0109] According to at least some example implementations, the predetermined condition is a condition that current handover related information is different from previous handover related information, wherein the previous handover related information was acquired and reported by the communications device before receiving the HO command.

[0110] According to at least some example embodiments, alternatively or additionally, the predetermined condition is a condition that a certain duration T has elapsed since receipt of a handover command prior to initiating execution of the conditional handover CHO.

[0111] According to an example embodiment, the apparatus further comprises: a component for obtaining an instruction to record current handover related information only when a predetermined condition is satisfied and / or obtaining a predetermined condition from at least one of a system information parameter and / or information related to a handover command.

[0112] According to an example embodiment, the switching-related information includes beam information about a beam radiated by a serving network cell and serving the communication device and / or about a beam radiated by another network cell among multiple network cells, cell information obtained by the communication device from the serving network cell and / or other network cells among multiple network cells, and at least one of the position and / or speed of the communication device.

[0113] According to an example embodiment, the predetermined condition is satisfied if the current handover related information differs from the previous handover related information by at least a certain threshold.

[0114] According to an example embodiment, in a case where the current handover related information includes an item that is not included in the previous handover related information, the predetermined condition is satisfied.

[0115] According to an example embodiment, the predetermined condition is satisfied if at least one of the beam of the serving network cell and the beam of the neighboring network cell has changed since receiving the HO command.

[0116] According to an example embodiment, the apparatus further comprises means for initiating HO execution after receiving the handover command, or means for initiating HO execution after receiving the handover command and if predefined handover conditions for HO execution are met.

[0117] According to an example embodiment, the apparatus further includes a component for sending an indication of the availability of recorded current switching related information to other network cells among the multiple network cells providing communication services after performing a random access channel RACH access between the communication device and other network cells among the multiple network cells after initiating HO execution.

[0118] According to an example embodiment, the device also includes: a component for receiving a request to report the recorded current switching related information from other network cells among the multiple network cells providing communication services when sending an indication of the availability of the recorded current switching related information to other network cells among the multiple network cells providing communication services.

[0119] According to an example embodiment, the apparatus further comprises means for sending the recorded current handover related information to other network cells among the plurality of network cells upon receiving a request to report the recorded current handover related information from other network cells among the plurality of network cells.

[0120] According to an example embodiment, the transmission of the recorded current handover related information is performed directly after or during the completion of the handover execution.

[0121] According to an example embodiment, the time for CHO execution is defined by the time for sending a random access channel RACH preamble.

[0122] According to an example embodiment, the time for handover execution is defined by the time when the CHO condition is met.

[0123] According to an example embodiment, the certain duration T is scaled by the mobility state of the communication device.

[0124] According to an example embodiment, the specific duration T is given in at least one of seconds, milliseconds, a number of elapsed radio frames, subframes, time slots and / or Orthogonal Frequency Division Multiplexing OFDM symbols.

[0125] According to at least some example embodiments, there is provided an apparatus for use by a serving network cell among a plurality of network cells that provides a communication service for a communication device. For example, the apparatus includes Figure 8 The control unit 20 shown. According to another exemplary embodiment or in addition, the device is configured to perform Figure 4 Method 2 is shown.

[0126] The apparatus comprises: a component for sending a handover HO command to a communication device to handover the communication device to another network cell among a plurality of network cells, wherein the handover command comprises a predetermined condition when current handover related information will be recorded.

[0127] According to at least some example embodiments, the predetermined condition is a condition that current handover related information is different from previous handover related information, wherein the previous handover related information is acquired and reported by the communications device before receiving the HO command.

[0128] According to at least some example embodiments, alternatively or additionally, the predetermined condition is a condition that a certain duration T has elapsed since receipt of a handover command before initiating execution of the conditional handover CHO.

[0129] According to an example embodiment, the switching-related information includes beam information about a beam radiated by a serving network cell and serving the communication device and / or about a beam radiated by another network cell among multiple network cells, cell information obtained by the communication device from the serving network cell and / or other network cells among multiple network cells, and at least one of the position and / or speed of the communication device.

[0130] According to an example embodiment, the predetermined condition is satisfied if the current handover related information differs from the previous handover related information by at least a certain threshold.

[0131] According to an example embodiment, in a case where the handover related information includes an item that is not included in the previous handover related information, the predetermined condition is satisfied.

[0132] According to an example embodiment, the predetermined condition is satisfied if at least one of the beam of the serving network cell and the beam of the neighboring network cell has changed since receiving the HO command.

[0133] According to an example embodiment, the device also includes: a component for receiving recorded current switching related information from other network cells among multiple network cells via an Xn interface, and the other network cells among the multiple network cells receive the recorded current switching related information from a communication device, wherein the other network cells among the multiple network cells are target cells.

[0134] In an example embodiment, the specific duration T is scaled by the mobility state of the communication device.

[0135] In an example embodiment, the specific duration T is given in at least one of seconds, milliseconds, number of elapsed radio frames, subframes, time slots and / or Orthogonal Frequency Division Multiplexing (OFDM) symbols.

[0136] It is to be understood that what has been described above is what is currently considered to be the preferred exemplary embodiment of the present invention. However, it should be noted that the description of the preferred exemplary embodiment is given by way of example only and that various modifications may be made without departing from the scope of the present invention as defined by the appended claims.

Claims

1. A method for use by a communication device, the method comprising: receiving a handover HO command from a serving network cell among a plurality of network cells, the serving network cell providing a communication service for the communication device, Get the current switch related information. Only when a predetermined condition is met, recording the current handover related information, wherein the handover related information includes information about a beam radiated by the serving network cell and serving the communication device, The predetermined condition is a condition that the current handover related information is different from the previous handover related information, wherein the previous handover related information is acquired and reported by the communication device before receiving the HO command, and wherein the predetermined condition also includes a condition that a specific duration T has passed since the handover command was received before initiating the conditional handover CHO execution.

2. The method according to claim 1, further comprising: An instruction to record the current handover related information only when the predetermined condition is satisfied and / or the predetermined condition is obtained from at least one of a system information parameter and / or information related to the handover command.

3. The method according to claim 1, wherein the handover related information comprises at least one of the following: beam information about a beam radiated by another network cell of the plurality of network cells, cell information acquired by the communication device from the serving network cell and / or the another network cell among the plurality of network cells, and The position and / or velocity of the communications device. 4 . The method according to claim 1 , wherein the predetermined condition is satisfied if the current handover related information differs from the previous handover related information by at least a certain threshold. 5 . The method according to claim 1 , wherein the predetermined condition is satisfied in a case where the current handover related information includes an item that is not included in the previous handover related information.

6. The method of claim 1, wherein the predetermined condition is satisfied if at least one of the beam of the serving network cell and the beam of the neighboring network cell has changed since the HO command was received.

7. The method according to claim 1, further comprising: Initiate HO execution after receiving the handover command, or After receiving the handover command and if predefined handover conditions for the HO execution are met, the HO execution is initiated.

8. The method according to claim 7, further comprising: The HO execution has been initiated, and after performing a random access channel RACH access between the communication device and another network cell among the multiple network cells, an indication of the availability of the recorded current switching related information is sent to the other network cell among the multiple network cells that provides the communication service.

9. The method according to claim 8, further comprising: When the indication regarding the availability of the recorded current switching related information is sent to the another network cell among the multiple network cells providing the communication service, a request for reporting the recorded current switching related information is received from the another network cell among the multiple network cells providing the communication service.

10. The method according to claim 9, further comprising: When the request for reporting the recorded current handover related information is received from the another network cell among the multiple network cells, the recorded current handover related information is sent to the another network cell among the multiple network cells.

11. The method according to any one of claims 1 to 7, wherein the sending of the recorded current handover related information is directly performed after or during the completion of handover execution.

12. A method used by a serving network cell in a plurality of network cells for providing communication services to a communication device, the method comprising: sending a handover HO command to the communication device, so as to hand over the communication device to another network cell among the plurality of network cells, The switching command includes a predetermined condition for when the current switching related information is to be recorded. The predetermined condition is a condition that the current handover related information is different from the previous handover related information, wherein the previous handover related information is acquired and reported by the communication device before receiving the HO command, wherein the handover related information includes information about a beam radiated by the service network cell and serving the communication device, and wherein the predetermined condition also includes a condition that a specific duration T has passed since the handover command was received before the conditional handover CHO is initiated.

13. The method according to claim 12, wherein the handover related information comprises at least one of the following: beam information about a beam radiated by another network cell of the plurality of network cells, cell information acquired by the communication device from the serving network cell and / or the another network cell among the plurality of network cells, and The position and / or velocity of the communications device.

14. The method of claim 12, wherein the predetermined condition is satisfied if the current handover related information differs from the previous handover related information by at least a certain threshold. 15 . The method according to claim 12 , wherein the predetermined condition is satisfied in a case where the handover related information includes an item that is not included in the previous handover related information.

16. The method of claim 13, wherein the predetermined condition is satisfied if at least one of the beam of the serving network cell and the beam of the neighboring network cell has changed since receiving the HO command.

17. The method according to any one of claims 12 to 16, further comprising: The recorded current switching related information is received from the another network cell among the multiple network cells via an Xn interface, and the another network cell receives the recorded current switching related information from the communication device, wherein the another network cell among the multiple network cells is a target cell.

18. A non-transitory computer-readable storage medium storing a program comprising software code portions which, when executed on a processor of a communication device, cause the processor to perform: receiving a handover HO command from a serving network cell among a plurality of network cells, the serving network cell providing a communication service for the communication device, Get the current switch related information. only if a predetermined condition is met, recording the current handover related information, wherein the handover related information includes information about a beam radiated by the serving network cell and serving the communication device, The predetermined condition is a condition that the current handover related information is different from the previous handover related information, wherein the previous handover related information is acquired and reported by the communication device before receiving the HO command, and wherein the predetermined condition also includes a condition that a specific duration T has passed since the handover command was received before initiating the conditional handover CHO execution.

19. A non-transitory computer-readable storage medium storing a program including a software code portion, which, when executed on a processor of a serving network cell providing a communication service to a communication device among a plurality of network cells, causes the processor to execute: sending a handover HO command to the communication device to hand over the communication device to another network cell among the plurality of network cells, The switching command includes a predetermined condition for when the current switching related information is to be recorded. The predetermined condition is a condition that the current handover related information is different from the previous handover related information, wherein the previous handover related information is acquired and reported by the communication device before receiving the HO command, wherein the handover related information includes information about a beam radiated by the service network cell and serving the communication device, and wherein the predetermined condition also includes a condition that a specific duration T has passed since the handover command was received before the conditional handover CHO is initiated.

20. An apparatus for use by a communication device, the apparatus comprising at least one processor and at least one memory, the at least one memory comprising computer program code, the at least one memory and the computer program code being configured to, together with the at least one processor, cause the apparatus to at least perform: receiving a handover HO command from a serving network cell among a plurality of network cells, the serving network cell providing a communication service for the communication device, Get the current switch related information. only if a predetermined condition is met, recording the current handover related information, wherein the handover related information includes information about a beam radiated by the serving network cell and serving the communication device, The predetermined condition is a condition that the current handover related information is different from the previous handover related information, wherein the previous handover related information is acquired and reported by the communication device before receiving the HO command, and wherein the predetermined condition also includes a condition that a specific duration T has passed since the handover command was received before initiating the conditional handover CHO execution.

21. The apparatus of claim 20, wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to further perform: An instruction to record the current handover related information only when the predetermined condition is satisfied and / or the predetermined condition is obtained from at least one of a system information parameter and / or information related to the handover command.

22. The apparatus according to claim 20, wherein the handover related information comprises at least one of the following: beam information about a beam radiated by another network cell of the plurality of network cells, cell information acquired by the communication device from the serving network cell and / or the another network cell among the plurality of network cells, and The position and / or velocity of the communications device.

23. The apparatus of claim 20, wherein the predetermined condition is satisfied if the current handover-related information differs from the previous handover-related information by at least a specific threshold. 24 . The apparatus according to claim 20 , wherein the predetermined condition is satisfied if the handover related information includes an item that is not included in the previous handover related information.

25. The apparatus of claim 22, wherein the predetermined condition is satisfied if at least one of the beam of the serving network cell and the beam of the neighboring network cell has changed since the HO command was received.

26. The apparatus of claim 20, wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to further perform: Initiate HO execution after receiving the handover command, or After receiving the handover command and if predefined handover conditions for the HO execution are met, the HO execution is initiated.

27. The apparatus of claim 26, wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to further perform: The HO execution has been initiated, and after performing a random access channel RACH access between the communication device and another network cell among the multiple network cells, an indication of the availability of the recorded current switching related information is sent to the other network cell among the multiple network cells that provides the communication service.

28. The apparatus of claim 27, wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to further perform: When the indication regarding the availability of the recorded current switching related information is sent to the another network cell among the multiple network cells providing the communication service, a request for reporting the recorded current switching related information is received from the another network cell among the multiple network cells providing the communication service.

29. The apparatus of claim 28, wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to further perform: When the request for reporting the recorded current handover related information is received from the another network cell among the multiple network cells, the recorded current handover related information is sent to the another network cell among the multiple network cells.

30. The apparatus according to any one of claims 20 to 26, wherein the sending of the recorded current handover related information is directly performed after or during the completion of handover execution.

31. An apparatus for use by a serving network cell in a plurality of network cells that provides communication services for a communication device, the apparatus comprising at least one processor and at least one memory, the at least one memory comprising computer program code, the at least one memory and the computer program code being configured to, together with the at least one processor, cause the apparatus to at least perform: sending a handover HO command to the communication device, so as to hand over the communication device to another network cell among the plurality of network cells, The switching command includes a predetermined condition for when the current switching related information is to be recorded. The predetermined condition is a condition that the current handover related information is different from the previous handover related information, wherein the previous handover related information is acquired and reported by the communication device before receiving the HO command, wherein the handover related information includes information about a beam radiated by the service network cell and serving the communication device, and wherein the predetermined condition also includes a condition that a specific duration T has passed since the handover command was received before the conditional handover CHO is initiated.

32. The apparatus according to claim 31, wherein the handover related information comprises at least one of the following: beam information about a beam radiated by another network cell of the plurality of network cells, cell information acquired by the communication device from the serving network cell and / or the another network cell among the plurality of network cells, and The position and / or velocity of the communications device.

33. The apparatus of claim 31, wherein the predetermined condition is satisfied if the current handover-related information differs from the previous handover-related information by at least a specific threshold.

34. The apparatus according to claim 31, wherein the predetermined condition is satisfied if the handover related information includes an item that is not included in the previous handover related information.

35. The apparatus of claim 32, wherein the predetermined condition is satisfied if at least one of the beam of the serving network cell and the beam of the neighboring network cell has changed since the HO command was received.

36. The apparatus according to any one of claims 31 to 35, wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to further perform: The recorded current switching related information is received from the another network cell among the multiple network cells via an Xn interface, and the another network cell receives the recorded current switching related information from the communication device, wherein the another network cell among the multiple network cells is a target cell.

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