Method and device for operating beam hopping pattern in consideration of cell DTX / DRX in mobile communication system supporting ntn

Abstract

The present disclosure relates to a method and device for operating cell discontinuous transmission (DTX) / discontinuous reception (DRX) and a beam hopping pattern considering same in a mobile communication system supporting NTN. To this end, a communication method performed by a user equipment (UE) comprises: receiving first configuration information about a dwell time according to a beam hopping pattern of a specific cell of a network; receiving second configuration information about an activation period according to cell discontinuous transmission / reception (DTX / DRX) of the specific cell, wherein the activation period according to the second configuration information is configured to include, in a time domain, an overlapping region with the dwell time according to the first configuration information; and transmitting and receiving signals to and from the network through the specific cell in the overlapping region.

Description

Method and device for operating beam hopping pattern considering cell DTX / DRX in mobile communication system supporting NTN

[0001] The following description relates to a mobile communication system supporting a Non-Terrestrial Network (NTN), and more specifically, to a method and device for operating cell DTX (Discontinuous Transmission) / DRX (Discontinuous Reception) and a beam hopping pattern considering the same in a mobile communication system supporting an NTN.

[0002] 3GPP (3rd Generation Partnership Project), which leads the technical standards for mobile communication systems rd The Generation Partnership Project is discussing the introduction of NTN to support non-terrestrial networks such as satellites in LTE and 5G.

[0003] Discussions on NTN have been ongoing since Release 16, and Release 19 is exploring items to improve downlink coverage, improve uplink capacity / speed, support broadcast services over satellite networks, and support base station mode.

[0004] Meanwhile, various technologies are being proposed to secure the number of available beams to improve the downlink coverage of NTN.

[0005] Accordingly, in one aspect of the present invention, a method and a device therefor are proposed for setting a beam hopping pattern to secure the number of available beams for improving downlink coverage in a mobile communication system supporting NTN, and performing communication based thereon.

[0006] In addition, in an embodiment of the present invention, we look into cell DTX / DRX proposed for NES (Network Energy Saving), and provide a method and device for operating a beam hopping pattern considering cell DTX / DRX.

[0007] The technology proposed below is assumed to be applicable not only to the current 5G system but also to 6G and subsequent mobile communication systems. Therefore, terms such as 'NTN', 'gNB', 'SIB (System Information Block) 1', and 'SIB 19' used in 5G may be considered as replacements for other terms in the next-generation standard corresponding to the basic concepts of satellite-based communication, network nodes corresponding to base stations, basic system information units for subsequent system information transmission, and system information units for NTN, respectively. However, for the convenience of the explanation below, terms specified in the current 5G standard may be used.

[0008] The problems to be solved by the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present invention belongs from the description below.

[0009] In one aspect of the present invention for solving the above-described problem, a method for a user equipment (UE) to perform communication with a network in a mobile communication system supporting a Non-Terrestrial Network (NTN), the method comprising: receiving first configuration information on a dwell time according to a beam hopping pattern of a specific cell of the network; receiving second configuration information on an activation period according to cell DTX / DRX (Cell Discontinuous Transmission / Reception) of the specific cell, wherein the activation period according to the second configuration information is set to include an overlapping area in the dwell time and time domain according to the first configuration information; and transmitting and receiving a signal with the network through the specific cell in the overlapping area.

[0010] In another aspect of the present invention for solving the above-described problem, a user equipment (UE) for performing communication with a network in a mobile communication system supporting a Non-Terrestrial Network (NTN), the UE comprises: at least one processor; and at least one computer memory operably connected to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform operations, wherein the operations include receiving first configuration information on a dwell time according to a beam hopping pattern of a specific cell of the network; receiving second configuration information on an activation period according to cell DTX / DRX (Cell Discontinuous Transmission / Reception) of the specific cell, wherein the activation period according to the second configuration information is set to include an overlapping area in a time domain with the dwell time according to the first configuration information; and transmitting and receiving a signal with the network through the specific cell in the overlapping area.

[0011] In another aspect of the present invention for solving the above-described problem, a method for a network to perform communication with a user equipment (UE) in a mobile communication system supporting a Non-Terrestrial Network (NTN), is proposed, comprising: setting a beam hopping pattern for a plurality of cells supported by the network; transmitting first configuration information on a dwell time according to the beam hopping pattern of a specific cell among the plurality of cells to the UE; transmitting second configuration information on an activation period according to cell DTX / DRX (Cell Discontinuous Transmission / Reception) of the specific cell to the UE, wherein the activation period according to the second configuration information is set to include an overlapping area in the dwell time and time domain according to the first configuration information; and transmitting and receiving a signal with the UE through the specific cell in the overlapping area.

[0012] In another aspect of the present invention for solving the above-described problem, a network for performing communication with a user equipment (UE) in a mobile communication system supporting a Non-Terrestrial Network (NTN) is proposed, comprising: at least one processor; and at least one computer memory operably connected to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform operations, wherein the operations include: setting a beam hopping pattern for a plurality of cells supported by the network; transmitting first configuration information regarding a dwell time according to a beam hopping pattern of a specific cell among the plurality of cells to the UE; transmitting second configuration information regarding an activation period according to cell DTX / DRX (Cell Discontinuous Transmission / Reception) of the specific cell to the UE, wherein the activation period according to the second configuration information is set to include an overlapping area in a time domain with the dwell time according to the first configuration information; and transmitting and receiving a signal with the UE through the specific cell in the overlapping area.

[0013] In one embodiment, the first configuration information may be cell specific configuration information, and the second configuration information may be user specific configuration information.

[0014] In one embodiment, the activation period may be set within the dwell time range.

[0015] In one embodiment, if the activation period includes a period other than the residence time, the overlapping area may be considered as the activation period.

[0016] In one embodiment, the first configuration information additionally includes information for a revisit cycle, and the second configuration information additionally includes information for a cycle of the cell DTRX / DRX, wherein the cycle of the cell DTRX / DRX can be set to an integer multiple of the revisit cycle.

[0017] In one embodiment, the information for the cycle of the cell DTRX / DRX may represent the integer multiple.

[0018] In one embodiment, in a time period corresponding to the residence time according to the first setting information or the activation period according to the second setting information, other than the overlapping area, the method may include performing at least one of reception of a Synchronization Signal Block (SSB) transmitted through the specific cell, reception of a Random Access Response (RAR), and reception of a Message 4 (Msg4) of random access.

[0019] In one embodiment, the first setting information may be set based on the second setting information.

[0020] At this time, the residence time is set based on the activation section, and the revisit cycle can be set based on the cycle information.

[0021] Additionally, when receiving the second setting information, the second setting information may additionally include updating the first setting information.

[0022] According to the embodiments of the present invention as described above, downlink coverage can be efficiently improved in a mobile communication system supporting NTN.

[0023] In addition, in the embodiment of the present invention, the cell DTX / DRX proposed for NES and the beam hopping pattern considering the same are specified for operation, so that the operation method of the UE for each situation can be clearly defined.

[0024] The effects that can be obtained from the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by a person having ordinary skill in the art to which the present invention belongs from the description below.

[0025] Figure 1 is a diagram illustrating the elements of NTN discussed in 3GPP.

[0026] Figure 2 is a drawing to explain the concept of the number of beams available in a system supporting NTN.

[0027] FIG. 3 is a diagram for explaining communication between a UE and a network in a mobile communication system supporting NTN according to one embodiment of the present invention.

[0028] FIG. 4 is a diagram for explaining the concept of SSB transmission cycle and residence time borrowed in one embodiment of the present invention.

[0029] FIGS. 5 to 7 are drawings for explaining time / frequency tracking errors when extending an SSB transmission cycle according to one embodiment of the present invention.

[0030] FIG. 8 is a diagram for explaining UE connection delay when extending an SSB transmission cycle according to one embodiment of the present invention.

[0031] FIG. 9 and FIG. 10 are drawings for explaining SSB transmission settings according to one embodiment of the present invention.

[0032] FIG. 11 is a drawing for explaining the concept of revisit time according to one embodiment of the present invention.

[0033] FIGS. 12 to 14 are drawings for explaining second setting information for cell DTX / DRX according to one embodiment of the present invention.

[0034] FIG. 15 is a diagram for explaining the relationship between a cell DTX and a DRX of a UE according to one embodiment of the present invention.

[0035] FIG. 16 is a diagram for explaining the concept of applying cell DTX / DRX in an NTN cell operating in a beam hopping manner according to one embodiment of the present invention.

[0036] Figure 17 illustrates a wireless device to which the present technology can be applied.

[0037] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings so that those skilled in the art can easily implement the present invention. However, the present invention may be implemented in various different forms and is not limited to the embodiments described herein. In addition, in the drawings, parts irrelevant to the description have been omitted to clearly explain the present invention, and similar parts have been designated with similar reference numerals throughout the specification.

[0038] Throughout the specification, whenever a part is said to "include" a component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise stated.

[0039]

[0040] As described above, one aspect of the present invention examines a method for securing the number of available beams in a system supporting NTN. To this end, we first examine the current state of NTN and the discussions surrounding downlink improvements within 3GPP.

[0041] Figure 1 is a diagram illustrating the elements of NTN discussed in 3GPP.

[0042] As illustrated in Figure 1, NTN generally includes the following elements:

[0043] First, it may include one or more gateways (110) that connect the NTN to a public data network. The satellite (120) may be implemented as a satellite or an Unmanned Aircraft System (UAS) as illustrated in FIG. 1, and the satellites may be classified into GEO satellites and non-GEO satellites.

[0044] A GEO satellite (120) may be served by one or more gateways (110) deployed across the satellite's target range (e.g., regional or continental range). It may be assumed that a UE (130) of a cell is served by a gateway (110).

[0045] A non-GEO satellite (120) can be successively served by one or more gateways (110) at a time. The system can ensure service and feeder link continuity between successive serving gateways for a sufficient time to perform mobility anchoring and handover.

[0046] A feeder link or wireless link may be established between the gateway (110) and the satellite (or UAS platform) (120). A service link or wireless link may be established between the UE (130) and the satellite (or UAS platform) (120).

[0047] Meanwhile, the beams generated by a satellite (or UAS platform) (120) typically generate multiple beams for a given service area bounded by its field of view. The footprints (140) of the beams may be generally elliptical, as illustrated in FIG. 1, but need not be limited thereto. The field of view of the satellite (or UAS platform) may depend on the onboard antenna diagram and the minimum elevation angle.

[0048] There may be different types of satellites (or UAS platforms) (120). The following table exemplifies types of NTN platforms.

[0049]

[0050] PlatformsAltitude RangeOrbitTypical beam footprint sizeLow-Earth Orbit(LEO) satellite300-1500 kmCircular around the earth100 - 1000 kmMedium-Earth Orbit (MEO) satellite7000 - 25000 km100 - 1000 kmGeostationary Earth Orbit (GEO) satellite35 786 kmnotional station keeping position fixed in terms of terms of elevation / azimuth with respect to a given earth point200 - 3500 kmUAS platform (including HAPS)8 - 50 km (20 km for HAPS)5 - 200 kmHigh Elliptical Orbit (HEO) satellite400 - 50000 kmElliptical around the earth200 - 3500 km

[0051] Typically, GEO satellites and UAS are used to provide continental, regional, or local services, while constellations of LEO and MEO satellites are used to provide services in both the Northern and Southern Hemispheres. In some cases, these constellations can provide global coverage, including polar regions.

[0052]

[0053] Figure 2 is a drawing to explain the concept of the number of beams available in a system supporting NTN.

[0054] Since SSB can only use a limited number of indices depending on the sub-carrier spacing, it is not possible to assign an independent index to every beam pattern in systems that use more than 1,000 beam footprints, such as satellite communications.

[0055] Therefore, in order to utilize all beam footprints within the existing specifications, it is desirable to increase the maximum number of operable beam footprints through beam hopping, which changes the beam footprint mapped to each SSB index when transmitting SSB every 20 ms. For example, if beam hopping is not used, the number of usable beam footprints in a base station using four SSB indices is 'the number of SSB indices x the number of activated beams'.

[0056] Here, the number of active beams is assumed to be the maximum number of beams that can satisfy the minimum signal level or higher, and in the example of utilizing four SSB indices as shown in Fig. 2, the number of active beams of the satellite (N Sat When the number of activeBeams is 16, the number of operable beam footprints is 64 (=4 x 16).

[0057] In addition, in embodiments of the present invention, in order to efficiently increase the number of beams that can be supported, it is assumed that the transmission cycle of SSB is extended from the existing 20 ms to 80 ms, 160 ms, 320 ms, etc., and the transmission cycle of SSB for such NTN service can be referred to as an 'extended cycle'.

[0058] FIG. 3 is a diagram for explaining communication between a UE and a network in a mobile communication system supporting NTN according to one embodiment of the present invention.

[0059] In one embodiment of the present invention, the above-described extension period corresponds to one of a plurality of candidate transmission periods, wherein it is assumed that the plurality of candidate transmission periods include periods greater than or equal to 160 ms, which is the maximum transmission period of conventional 5G. For example, the above-described extension period may be set to 320 ms or greater.

[0060] The network supporting NTN in FIG. 3 may be a node corresponding to a specific cell (Cell#n) in the mobile communication system described above with respect to FIG. 2. In addition, the network supporting NTN in FIG. 3 may determine a beam hopping pattern by considering the number of operating cells, the number of activated beams, etc., as described above with respect to FIG. 2 (S310).

[0061] Based on the beam hopping pattern determined in this manner, the network can transmit to the UE first configuration information regarding the dwell time according to the beam hopping pattern of a specific cell (Cell#n) (S320). The 'dwell time' can be viewed as the time for which a beam remains in a specific cell by applying beam hopping in the situation described above with reference to FIG. 2, and will be described in more detail below with examples.

[0062] Additionally, the first configuration information according to one embodiment of the present invention may include information for one or more of an SSB transmission period, a residence time, or a revisit time.

[0063] Meanwhile, as illustrated in FIG. 3, the network may transmit second configuration information for an activation period according to cell DTX / DRX of a specific cell (Cell#n) to the UE. Unlike the conventional UE DTX (C-DTX) applied to reduce power consumption of the UE, the cell DTX / DRX applies cell-level DTX / DRX to save energy on the network side, and will be described in more detail with examples below.

[0064]

[0065] In the embodiments of the present invention described below, the relationship between the beam hopping pattern according to the first setting information and the cell DYX / DRX is specifically defined.

[0066] If, as illustrated in FIG. 3, simultaneous configuration of a beam hopping pattern (first configuration information) for NTN and cell DTX / DRX (second configuration information) is allowed, in one embodiment of the present invention, an activation period according to the second configuration information is set to include an 'overlapping area' that overlaps the residence time and time domain according to the first configuration information, and the UE identifies such an overlapping area (S340) and transmits and receives a signal with the network through a specific cell (cell#n) in the overlapping area (S350).

[0067] To this end, below, we first examine the NTN beam hopping pattern and cell DTX / DRX in detail, and then examine their relationship.

[0068]

[0069] NTN beam hopping pattern

[0070] Among the NTN beam hopping patterns, the concept of extending the SSB transmission cycle described above is explained in more detail.

[0071] FIG. 4 is a diagram for explaining the concept of SSB transmission cycle and residence time borrowed in one embodiment of the present invention.

[0072] When transmitting a downlink signal in a beam hopping manner in a mobile communication system using NTN, SSB and / or SI can be transmitted in units of a specific active beam (active beam -1) as illustrated in FIG. 4. The example illustrated in FIG. 4 assumes that the SSB transmission period (410) is set to 160 ms.

[0073] Within the SSB transmission cycle (410), SSB / SI can be Time Domain Multiplexed (TDM) in units of 20 ms, and the 20 ms can be referred to as a TDM gap (TDM gap; 430). This TDM gap (430) can correspond to a footprint corresponding to each SSB, and data transmission and reception can be performed during the residence time (420) other than the SSB / SI transmission section in each TDM gap (430a, 430b).

[0074] In Fig. 4, the residence time (420) is separately illustrated as a data transmission period other than the SSB / SI reception period, but the residence time (420) may be defined differently depending on the embodiment, including the SSB / SI reception period, as a period in which UL / DL signal transmission and reception are possible through the cell. When the residence time is defined as in Fig. 4, in the embodiments below, the activation time period may be viewed as including the SSB / SI reception period, rather than corresponding to the residence time.

[0075]

[0076] FIGS. 5 to 7 are drawings for explaining time / frequency tracking errors when extending an SSB transmission cycle according to one embodiment of the present invention.

[0077] Specifically, FIG. 5 illustrates the transmission timing of SSB, SIB 1 / 19 and the transmission timing of downlink control channel (PDCCH) / downlink shared channel (PDSCH) for each UE when 640 ms is applied as an extension period, and FIG. 6 and FIG. 7 illustrate the time / frequency tracking error of each signal accordingly.

[0078] As illustrated in FIG. 5, SSB1 and SUB19 transmitted through common signal sweeping within a 10 ms interval have no time / frequency tracking error as illustrated at 610 and 620 in FIG. 6, respectively. In contrast, PDCCH / PDSCH may experience a certain level of time / frequency tracking error as illustrated at 710 and 720 in FIG. 7 due to the influence of the extended period, but the level of the above errors is judged to be tolerable in terms of securing downlink coverage as described above with respect to FIG. 2.

[0079] FIG. 8 is a diagram for explaining UE connection delay when extending an SSB transmission cycle according to one embodiment of the present invention.

[0080] As illustrated in FIG. 8, it may take approximately 75 ms for one UE to transition from RRC_INACTIVE state to RRC_CONNECTED state.

[0081] If, in one embodiment of the present invention, an extended period is applied, additional time delay may occur accordingly.

[0082] For example, if the SSB transmission period is extended to 640 ms, the UE's network access delay time is (640 + 75 =) 715 ms, which can be considered a tolerable level for the downlink coverage expansion of the NTN described above.

[0083] Accordingly, in one embodiment of the present invention, the SSB transmission period is set to be scalable as described above, and specifically, it is proposed to set it to one of a plurality of candidate SSB transmission periods and notify the UE through signaling, and at this time, the candidate SSB transmission period includes a period of 160 ms or more, and can include up to 320 ms and 640 ms as in the examples described above.

[0084]

[0085] FIG. 9 and FIG. 10 are drawings for explaining SSB transmission settings according to one embodiment of the present invention.

[0086] In the NR system, the SSB transmission period is set to any one of the candidate SSB transmission periods of 5 ms, 10 ms, 20 ms, 40 ms, 80 ms, and 160 ms, but generally, the 20 ms transmission period is most commonly used, and Fig. 9 illustrates the SSB transmission form according to this. The setting for this is illustrated in the structure that signals through ssb-periodicityServingCell when transmitting the SSB transmission period as shown in Fig. 10 through the ServingCellConfigCommon information element of SIB 1.

[0087] However, in one embodiment of the present invention, unlike the current NR system, it is proposed to design the system so that an extended period can be applied, and accordingly, as shown in FIG. 10, an extended period of 320 ms, 640 ms, etc. can be additionally included in the candidate SSB transmission period.

[0088] Meanwhile, as illustrated in FIG. 9, transmission of SSBs within an SSB burst can be performed within a 5 ms window. As illustrated in FIG. 9, the time domain pattern for transmitting SSBs within an SSB burst can vary depending on the subcarrier spacing and frequency band (910a - 950).

[0089] The maximum number of transmitted SSBs within an SSB burst (i.e., a 5 ms period) can be set to 4 in the band up to 3 GHz, 8 in the 3-6 GHz band, and 64 in the 6-52.6 GHz band. However, the actual number of transmitted SSBs within this upper limit range can be set separately.

[0090] In the example of FIG. 9, 910a exemplarily shows a case where the subcarrier spacing (SCS) is 15 kHz in a band below 3 GHz, 910b exemplarily shows a case where the SCS is 15 kHz in a band between 3 and 6 GHz, 920a exemplarily shows a case where the SCS is 30 kHz in a band below 3 GHz, 920b exemplarily shows a case where the SCS is 30 kHz in a band between 3 and 6 GHz, 930a exemplarily shows a case where the SCS is 30 kHz in a band below 3 GHz, 930b exemplarily shows a case where the SCS is 30 kHz in a band between 3 and 6 GHz, 940 exemplarily shows a case where the SCS is 120 kHz in a band below 6 GHz, and 950 exemplarily shows a case where the SCS is 240 kHz in a band above 6 GHz.

[0091] Although the example of FIG. 9 illustrates various transmission patterns according to the band and SCS, it is not excluded that the SSB transmission pattern may be changed by additional parameters in one embodiment of the present invention.

[0092] In one embodiment of the present invention, it is assumed that the UE operates under the assumption of a default SSB transmission period before receiving system information (SI corresponding to SIB 1 of NR) from the network regarding which SSB transmission period among the extended SSB transmission period candidates as illustrated in FIG. 10 is set. For example, the default SSB transmission period may be 20 ms as illustrated in FIG. 9 and FIG. 10 , and a different default transmission period may also be used in the NTN.

[0093]

[0094] FIG. 11 is a drawing for explaining the concept of revisit time according to one embodiment of the present invention.

[0095] Assuming a scenario using LEO600km Set1-1, which is currently being considered for use in FR1 in NTN, a total of 1058 beam footprints are set, but since a maximum of 106 beam footprints can be supported simultaneously, it can be seen that only about 10% of the beam footprints can be supported simultaneously.

[0096] Accordingly, it is desirable to secure downlink coverage by revisiting each cell (i.e., Cell#1, Cell#2, Cell#3, etc.) by applying beam hopping method, and therefore, as shown in Fig. 11, the time interval until revisiting a specific cell (Cell#1) is called revisit time (T rev ) can be defined. In the example of Fig. 11, this revisit time (T rev ) is set to 320 ms.

[0097] This revisit time (T rev ) is the time for which the cell (Cell#1) is activated, called the residence time (T dwell ) can be defined as, and in the example of Fig. 11, this residence time (T dwell ) is set to 20 ms. Each frame is divided into a frame interval (T frame ) can be transmitted based on the frame interval (T), and Fig. 11 shows the frame interval (T frame ) is set to 10 ms.

[0098] In the example of Fig. 11, the SSB transmission period is also the revisit time (T rev ) can be seen to be set to 320 ms, the same as the SSB transmission cycle. In this way, the revisit time (T rev ) may be the same as, but may be set differently as described below.

[0099]

[0100] Cell DTX / DRX

[0101] FIGS. 12 to 14 are drawings for explaining second setting information for cell DTX / DRX according to one embodiment of the present invention.

[0102] Cell DTX / DRX is a concept introduced to save energy of the cell on the network side, unlike DTX (C-DRX) for saving power of the UE. In embodiments of the present invention, it is assumed that cell DTX / DRX is applied only in RRC connection mode.

[0103] As illustrated in FIG. 12, an activation period (1230) may be set for each of the cell DTX (1210) and the cell DRX (1220), and this activation period (1230) may be represented by an activation period timer (e.g., onDurationTimer) (1310) as shown in an example of the second setting information of FIG. 13.

[0104] This activation period (1230) can be repeatedly set based on the cell DTX / DRX cycle (1240) as illustrated in FIG. 12. The cell DRX / DRX cycle (1240) can be specifically defined through the start offset of the cycle, slot offset, etc. (1320) as illustrated in FIG. 13.

[0105] The second setting information illustrated in FIG. 13 may additionally include information (1330) indicating whether to set DTX, set DRX, or set DTX and DRX as a setting type of cell DTX / DRX, and information (1340) indicating whether to activate cell DTX / DRX.

[0106]

[0107] As illustrated in FIG. 12, when cell DTX / DRX is set, a time period other than the active period (1310) can be defined as a deactivated period (1250).

[0108] As illustrated in FIG. 14, when the cell DTX is configured and activated (1210), the UE does not receive PDCCH, SPS PDSCH, or periodic / semi-static CSI-RS (1410) for CSI reporting during this inactive period (1250). This is indicated in FIG. 14 as a signal / channel (1410) affected by the cell DTX. With respect to the CSI-RS, the most recent CSI measurement opportunity can be viewed as an opportunity (1420a) that occurred during the active period (1230) of the cell DTX.

[0109] As illustrated in FIG. 14, when cell DRX is configured and activated (1220), the UE does not transmit CG (Configured Grant)-PUSCH, SR (Scheduling Request), periodic / semi-static CSI reporting, and periodic / semi-static SRS (Sounding Reference Signal). In FIG. 14, this is indicated as a signal / channel (1420) affected by cell DRX. With respect to SR, the UE may delay SR transmission until the activation period (1230) of cell DRX without triggering RACH.

[0110]

[0111] However, in one embodiment of the present invention, it is assumed that cell DTX / DRX operates so as not to affect SSB transmission, RA (Random Access) procedure, paging, SI (System Information) and HARQ-ACK feedback.

[0112] Specifically, the UE can transmit SSB even in the cell DTX deactivation period as before. In addition, the UE can monitor the PDCCH for the Random Access Response (RAR) and message 4 (msg4) of the RA procedure even in the cell DTX deactivation period. For this purpose, the RAR reception window (ra-ResponseWindow) and the RA contention resolution timer (ra-ContentionResolutionTimer) can be set regardless of the cell DTX / DRX.

[0113]

[0114] FIG. 15 is a diagram for explaining the relationship between a cell DTX and a DRX of a UE according to one embodiment of the present invention.

[0115] In one embodiment of the present invention, it is assumed that the cell DTX (1510) can be configured only when the C-DRX (1520) of the UE is configured. In contrast, it is assumed that the cell DRX can be configured independently of the C-DRX (1520) of the UE.

[0116] In this embodiment, it is assumed that the network is configured so that an at least partially overlapping interval (1550) can be set between the activation interval (1530) of the C-DRX of the UE and the activation interval (1540) of the cell DTX, as illustrated in FIG. 15. Accordingly, the UE can omit PDCCH monitoring for new transmissions in intervals other than the overlapping interval (1550) as illustrated in FIG. 15.

[0117]

[0118] NTN beam hopping pattern considering cell DTX / DRX

[0119] Based on the above description, the following describes a method of operating an NTN beam hopping pattern considering cell DTX / DRX.

[0120] As described above, there is a time period during which a specific cell can communicate due to a beam hopping pattern, and this can be defined by a residence time, a revisit time, etc. In addition, as described above, cell DTX / DRX can be additionally set for the cell in question for the purpose of NES.

[0121] (1) Method that does not allow simultaneous settings

[0122] In one embodiment of the present invention, it is proposed not to allow the above-described cell DTX / DRX configuration for NTN cells operating in a beam hopping manner.

[0123] Beam hopping in NTN, as shown in Figure 2, is designed to expand network coverage and can be seen as designed to maximize the use of limited available beams. In contrast, cell DTX / DRX, introduced for NES purposes, is intended to conserve available beams for NES purposes, and their objectives may conflict.

[0124]

[0125] (2) How to allow simultaneous settings

[0126] In another embodiment of the present invention, a method is proposed to allow the above-described cell DTX / DRX settings for NTN cells operating in a beam hopping manner, but to set them by taking into account the relationship between the two.

[0127] FIG. 16 is a diagram for explaining the concept of applying cell DTX / DRX in an NTN cell operating in a beam hopping manner according to one embodiment of the present invention.

[0128] In one embodiment of the present invention, it is assumed that beam hopping pattern configuration information (first configuration information) is transmitted by the network via cell-specific configuration information (e.g., SIB, ServingCellConfigCommon), including information such as dwell time and revisit cycle. The example of Fig. 16 illustrates an example in which the revisit time (Trev) of the beam hopping pattern (1610) is set to 320 ms and the dwell time (Tdwell) is set to 20 ms.

[0129] Meanwhile, in this embodiment, it is assumed that the cell DTX / DRX (1620) configuration is transmitted by the network as UE-specific configuration information (e.g., RRC, ServingCellConfig).

[0130] Under these assumptions, in one embodiment of the present invention, it is proposed that the activation period (1630) of the cell DTX / DRX is set so that there is an overlapping area with the residence time (1640) of the corresponding cell. Specifically, the activation period (1630) of the cell DTX / DRX can always be set to be limited within the residence time (1640) interval. As another example, if the activation period (1630) of the cell DTX / DRX is set outside the residence time (1640) interval, only the overlapping time interval can be assumed as the activation period.

[0131]

[0132] In addition, in one embodiment of the present invention, it is proposed that the cycle (1650) of the cell DTX / DRX is set in consideration of the revisit cycle (or SSB transmission cycle) (1660). Specifically, the cell DTX / DRX cycle (16500) can always be set to an integer multiple of the revisit cycle (1660). Accordingly, the second setting information may indicate an integer multiple for setting the cell DTX / DRX cycle (1650). If the cell DTX / DRX cycle (1650) is not set, it may be assumed to be the same as the revisit cycle (1660).

[0133] Under these settings, the UE can transmit and receive signals only in a region where the duration of stay (1640) set by beam hopping pattern setting information (first setting information) and the activation period (1630) of cell DTX / DRX setting (second setting information) overlap.

[0134] However, in addition to the overlapping section, the UE may perform one or more of reception of SSB transmitted through the specific cell, reception of RAR, and reception of message 4 (Msg4) of random access within the residence time section (1640) or activation section (1630).

[0135]

[0136] Meanwhile, another embodiment of the present invention proposes that a beam hopping pattern of a cell is determined based on cell DTX / DRX configuration information.

[0137] Specifically, the dwell time (T) of the beam hopping pattern dwel )(1640) can be set assuming the activation period information (1630) of the cell DTX / DRX (e.g., onDurationTimer setting information). In addition, the revisit time (T rev )(1660) can be set assuming that the cycle (1650) setting information of the cell DTX / DRX is used.

[0138] In this case, both cell DTX and DRX can be configured to be set. As a method of setting this, cell DTX / DRX setting information can be set in a cell-specific manner via SIB or in a UE-specific manner via RRC.

[0139] If the beam hopping pattern is set via SIB and the cell DTX / DRX is additionally set via RRC, the UE may ignore the existing beam hopping-related configuration information and determine the beam hopping pattern based on the cell DTX / DRX configuration.

[0140]

[0141] Figure 17 illustrates a wireless device to which the present technology can be applied.

[0142] Referring to FIG. 17, the first wireless device (100) and the second wireless device (200) can transmit and receive wireless signals via various wireless access technologies (e.g., LTE, NR, 6G). Here, the first wireless device (100) and the second wireless device (200) can each correspond to the UE and network of FIG. 3.

[0143] A first wireless device (100) includes one or more processors (102) and one or more memories (104), and may further include one or more transceivers (106) and / or one or more antennas (108). The processor (102) controls the memories (104) and / or the transceivers (106), and may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in this document. For example, the processor (102) may process information in the memory (104) to generate first information / signal, and then transmit a wireless signal including the first information / signal via the transceiver (106). In addition, the processor (102) may receive a wireless signal including second information / signal via the transceiver (106), and then store information obtained from signal processing of the second information / signal in the memory (104). The memory (104) may be connected to the processor (102) and may store various information related to the operation of the processor (102). For example, the memory (104) may perform some or all of the processes controlled by the processor (102), or may store software code including commands for performing the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this document. Here, the processor (102) and the memory (104) may be part of a communication modem / circuit / chip designed to implement a wireless communication technology (e.g., LTE E-UTRA, 5G NR). The transceiver (106) may be connected to the processor (102) and may transmit and / or receive wireless signals via one or more antennas (108). The transceiver (106) may include a transmitter and / or a receiver. The transceiver (106) may be used interchangeably with an RF (Radio Frequency) unit. In the present invention, a wireless device may also mean a communication modem / circuit / chip.

[0144] The second wireless device (200) includes one or more processors (202), one or more memories (204), and may further include one or more transceivers (206) and / or one or more antennas (208). The processor (202) controls the memories (204) and / or the transceivers (206), and may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in this document. For example, the processor (202) may process information in the memory (204) to generate third information / signals, and then transmit a wireless signal including the third information / signals via the transceivers (206). Furthermore, the processor (202) may receive a wireless signal including fourth information / signals via the transceivers (206), and then store information obtained from signal processing of the fourth information / signals in the memory (204). The memory (204) may be connected to the processor (202) and may store various information related to the operation of the processor (202). For example, the memory (204) may store software code including commands for performing some or all of the processes controlled by the processor (202) or for performing the descriptions, functions, procedures, proposals, methods and / or operation flowcharts disclosed in this document. Here, the processor (202) and the memory (204) may be part of a communication modem / circuit / chip designed to implement a wireless communication technology (e.g., LTE E-UTRA, 5G NR). The transceiver (206) may be connected to the processor (202) and may transmit and / or receive wireless signals via one or more antennas (208). The transceiver (206) may include a transmitter and / or a receiver. The transceiver (206) may be used interchangeably with an RF unit. In the present invention, a wireless device may also mean a communication modem / circuit / chip.

[0145] Hereinafter, the hardware elements of the wireless device (100, 200) will be described in more detail. Although not limited thereto, one or more protocol layers may be implemented by one or more processors (102, 202). For example, one or more processors (102, 202) may implement one or more layers (e.g., functional layers such as PHY, MAC, RLC, PDCP, RRC, SDAP). One or more processors (102, 202) may generate one or more Protocol Data Units (PDUs) and / or one or more Service Data Units (SDUs) according to the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this document. One or more processors (102, 202) may generate messages, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this document. One or more processors (102, 202) can generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data or information according to the functions, procedures, proposals and / or methods disclosed herein, and provide the signals to one or more transceivers (106, 206). One or more processors (102, 202) can receive signals (e.g., baseband signals) from one or more transceivers (106, 206) and obtain PDUs, SDUs, messages, control information, data or information according to the descriptions, functions, procedures, proposals, methods and / or operational flowcharts disclosed herein.

[0146] One or more processors (102, 202) may be referred to as a controller, a microcontroller, a microprocessor, or a microcomputer. One or more processors (102, 202) may be implemented by hardware, firmware, software, or a combination thereof. For example, one or more Application Specific Integrated Circuits (ASICs), one or more Digital Signal Processors (DSPs), one or more Digital Signal Processing Devices (DSPDs), one or more Programmable Logic Devices (PLDs), or one or more Field Programmable Gate Arrays (FPGAs) may be included in one or more processors (102, 202). The descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in this document may be implemented using firmware or software, and the firmware or software may be implemented to include modules, procedures, functions, etc. The descriptions, functions, procedures, suggestions, methods and / or operation flowcharts disclosed in this document may be implemented using firmware or software configured to perform one or more processors (102, 202) or stored in one or more memories (104, 204) and executed by one or more processors (102, 202). The descriptions, functions, procedures, suggestions, methods and / or operation flowcharts disclosed in this document may be implemented using firmware or software in the form of codes, instructions and / or sets of instructions.

[0147] One or more memories (104, 204) may be coupled to one or more processors (102, 202) and may store various forms of data, signals, messages, information, programs, codes, instructions, and / or commands. The one or more memories (104, 204) may be configured as ROM, RAM, EPROM, flash memory, hard drives, registers, cache memory, computer-readable storage media, and / or combinations thereof. The one or more memories (104, 204) may be located internally and / or externally to the one or more processors (102, 202). Additionally, the one or more memories (104, 204) may be coupled to the one or more processors (102, 202) via various technologies, such as wired or wireless connections.

[0148] One or more transceivers (106, 206) can transmit user data, control information, wireless signals / channels, etc., as mentioned in the methods and / or flowcharts of this document, to one or more other devices. One or more transceivers (106, 206) can receive user data, control information, wireless signals / channels, etc., as mentioned in the descriptions, functions, procedures, proposals, methods and / or flowcharts of this document, from one or more other devices. For example, one or more transceivers (106, 206) can be connected to one or more processors (102, 202) and can transmit and receive wireless signals. For example, one or more processors (102, 202) can control one or more transceivers (106, 206) to transmit user data, control information, or wireless signals to one or more other devices. Additionally, one or more processors (102, 202) may control one or more transceivers (106, 206) to receive user data, control information, or wireless signals from one or more other devices. Additionally, one or more transceivers (106, 206) may be coupled to one or more antennas (108, 208), and one or more transceivers (106, 206) may be configured to transmit and receive user data, control information, wireless signals / channels, or the like, as referred to in the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed herein, via one or more antennas (108, 208). In this document, one or more antennas may be multiple physical antennas or multiple logical antennas (e.g., antenna ports). One or more transceivers (106, 206) can convert received user data, control information, wireless signals / channels, etc. from RF band signals to baseband signals in order to process the received user data, control information, wireless signals / channels, etc. using one or more processors (102, 202).One or more transceivers (106, 206) may convert user data, control information, wireless signals / channels, etc. processed by one or more processors (102, 202) from baseband signals to RF band signals. For this purpose, one or more transceivers (106, 206) may include an (analog) oscillator and / or filter.

[0149]

[0150] The detailed description of the preferred embodiments of the present invention disclosed above has been provided to enable those skilled in the art to implement and practice the present invention. While the above description has been made with reference to preferred embodiments of the present invention, those skilled in the art will appreciate that various modifications and variations can be made to the present invention without departing from the scope of the present invention. For example, those skilled in the art can utilize the individual components described in the above-described embodiments in combination with each other.

[0151] Accordingly, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0152] The method and device for operating cell DTX / DRX and a beam hopping pattern considering the cell DTX / DRX in a mobile communication system supporting NTN according to the embodiments of the present invention described above are suitable for use in a communication environment utilizing NTN discussed in 3GPP, but can also be widely used in an environment utilizing satellite-based communication in a communication method other than 3GPP.

Claims

1. In a mobile communication system supporting NTN (Non-Terrestrial Network), a method for a user equipment (UE) to perform communication with a network, Receive first setting information about a dwell time according to a beam hopping pattern of a specific cell of the above network; Receive second configuration information for the activation period according to the cell DTX / DRX (Cell Discontinuous Transmission / Reception) of the above specific cell, The activation section according to the second setting information is set to include an overlapping area in the residence time and time domain according to the first setting information; and Including transmitting and receiving signals to and from the network through the specific cell in the overlapping area, UE's communication method.

2. In paragraph 1, The above first setting information is cell specific setting information, The above second setting information is user specific setting information. UE's communication method.

3. In paragraph 1, The above activation period is set within the above dwell time range, UE's communication method.

4. In paragraph 1, If the above-mentioned activation section includes a section other than the above-mentioned residence time, the overlapping area is regarded as the above-mentioned activation section. UE's communication method.

5. In paragraph 1, The above first setting information additionally includes information for the revisit cycle, The above second setting information additionally includes information for the cycle of the cell DTRX / DRX, The cycle of the above cell DTRX / DRX is set to an integer multiple of the revisit cycle. UE's communication method.

6. In paragraph 5, Information for the cycle of the above cell DTRX / DRX represents the integer multiple, UE's communication method.

7. In paragraph 1, In a time section corresponding to the residence time according to the first setting information or the activation section according to the second setting information, other than the above overlapping area, Including performing at least one of reception of SSB (Synchronization Signal Block) transmitted through the specific cell, reception of RAR (Random Access Response), and reception of Message 4 (Msg4) of random access. UE's communication method.

8. In paragraph 5, The above first setting information is set based on the above second setting information, UE's communication method.

9. In paragraph 8, The above dwell time is set based on the above activation period, The above revisit cycle is set based on the above cycle information. UE's communication method.

10. In paragraph 8, When receiving the second setting information, the second setting information additionally includes updating the first setting information. UE's communication method.

11. In a user equipment (UE) that performs network communication in a mobile communication system supporting NTN (Non-Terrestrial Network), at least one processor; and At least one computer memory operably connected to said at least one processor and storing instructions that, when executed, cause said at least one processor to perform operations; The above actions are, Receive first setting information about a dwell time according to a beam hopping pattern of a specific cell of the above network; Receive second configuration information for the activation period according to the cell DTX / DRX (Cell Discontinuous Transmission / Reception) of the above specific cell, The activation section according to the second setting information is set to include an overlapping area in the residence time and time domain according to the first setting information; and Including transmitting and receiving signals to and from the network through the specific cell in the overlapping area, User device.

12. In a mobile communication system supporting NTN (Non-Terrestrial Network), a method for a network to communicate with a user equipment (UE), Setting a beam hopping pattern for multiple cells supported by the above network; Transmit first setting information about a dwell time according to a beam hopping pattern of a specific cell among the plurality of cells to the UE; Transmitting second configuration information for the activation period according to the cell DTX / DRX (Cell Discontinuous Transmission / Reception) of the specific cell to the UE, The activation section according to the second setting information is set to include an overlapping area in the residence time and time domain according to the first setting information; and Including transmitting and receiving signals with the UE through the specific cell in the overlapping area, Communication methods in networks.

13. In a network that performs communication with a user equipment (UE) in a mobile communication system supporting NTN (Non-Terrestrial Network), at least one processor; and At least one computer memory operably connected to said at least one processor and storing instructions that, when executed, cause said at least one processor to perform operations; The above actions are, Setting a beam hopping pattern for multiple cells supported by the above network; Transmit first setting information about a dwell time according to a beam hopping pattern of a specific cell among the plurality of cells to the UE; Transmitting second configuration information for the activation period according to the cell DTX / DRX (Cell Discontinuous Transmission / Reception) of the specific cell to the UE, The activation section according to the second setting information is set to include an overlapping area in the residence time and time domain according to the first setting information; and Including transmitting and receiving signals with the UE through the specific cell in the overlapping area, network.

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