A method for bandwidth part adaptation

Abstract

The present invention relates to wireless communications, and more particularly, to a method for Orbit Aware BWP adaptation of users with zones.

Description

[0001] A METHOD FOR BANDWIDTH PART ADAPTATION

[0002] TECHNICAL FIELD

[0003] The present invention relates to wireless communications, and more particularly, to a method for Orbit Aware Bandwidth Part (BWP) adaptation of users with zones.

[0004] PRIOR ART

[0005] Bandwidth part adaptation was introduced with 5G NR and is a method that enables power saving by allowing the user to receive and send only in a small part of the bandwidth instead of scanning the entire bandwidth. Bandwidth Part Adaptation method is for reducing the power consumption of 5G NR devices. In current 3GPP standards, users can be configured with four different downlink BWPs and four different uplink BWPs, one of which is active for both uplink and downlink at the same time. Each user may have different bandwidth needs. For this reason, bandwidth segments of different sizes can be assigned for both uplink and downlink. Since the individual needs of users are taken into consideration, delays are caused during the bandwidth part switching.

[0006] Dynamic Bandwidth Part (BWP) allocation based on user needs and environmental conditions refers to the dynamic adjustment of bandwidth allocation in future mobile communication systems such as 6G. This allows the communication system to optimize bandwidth allocation to provide better service to users.

[0007] For example, when a user is located in a congested area or engages in intensive data transfer, the communication infrastructure can allocate wider bandwidth. This results in higher data rates and better communication quality. Conversely, if the user moves to a less congested area or reduces data transfer, the bandwidth can be automatically reduced or allocated to another user.

[0008] This dynamic bandwidth allocation approach enhances network efficiency and improves user experience in mobile communication systems. User-centric BWP bandwidth changes provide flexibility and optimized performance, allowing the network to better respond to user demands while efficiently utilizing resources.

[0009] In the prior of the art, there are some inventions that serve different purposes, both for grouping and for constraints. Some of them are explained below.

[0010] Patent document W02021007082A1 relates to spectrum sharing for a terrestrialsatellite hybrid environment. It is mentioned that in this invention, each of the 4 BWPs assigned to the users can be configured for a different purpose. For example, one of the allocated BWPs will be used for terrestrial networks, another BWP will be used for satellite communication, etc. Assigning BWPs to different purposes in this way.

[0011] Another approach is described in patent document WO2022241384A1.This patent document relates to power savings for reduced capability devices. The invention refers to a new signaling method for determining a group of BWPs for users who do not have sufficient capability to work, all users with low capability can use this BWP and switch to this BWP.

[0012] Article document (Method to Handle BWP Inactivity Timer to Reduce Latency and to Improve Throughput in 5G Devices, IEEE, 2021 IEEE 4th 5G World Forum (5GWF)) relates to method to handle BWP inactivity timer to reduce latency and to improve throughput in 5G devices. In this paper, an Efficient BWP Switch Method (EBSM) novel algorithm proposed to handle BWP-lnactivity Timer to reduce latency and thereby increase the system throughput during larger gap lengths configured for accurate positioning measurements. An optimization study that tries to minimize the amount of delay is described for delays during the BWP changes process.

[0013] Background information about the bandwidth part adaptation is given below.

[0014] Fundamentals of Bandwidth Parts

[0015] 5G New Radio (NR) has the capability to accommodate broad carrier bandwidths, reaching 200 MHz for Frequency Range 1 (FR1 , which covers frequencies below 6 GHz) and up to 400 MHz for Frequency Range 2 (FR2, spanning from 24 to 52 GHz). To enable this, 3GPP Release 15 introduced Bandwidth Part (BWP), which enables receivers to adapt to varying bandwidths, serving as a crucial element of the 5G NR access interface.

[0016] NR defines scalable orthogonal frequency division multiplexing (OFDM) numerologies using subcarrier spacing (SCS) of 2 / / -15 kHz ( / i = 0, 1, .... 4). An RB consists of 12 consecutive subcarriers in the frequency domain. NR uses “Point A” as a common reference point for RB grids. A BWP starts at a certain common RB and consists of a set of contiguous RBs with a given numerology (SCS and cyclic prefix) on a given carrier. For each serving cell of a UE, the network configures at least one downlink (DL) BWP (i.e. , the initial DL BWP). The network may configure the UE with up to four DL BWPs, but only one DL BWP can be active at a given time. If the serving cell is configured with an uplink (UL), the network configures at least one UL BWP. Similar to the DL, the network may configure the UE with up to four UL BWPs, but only one UL BWP can be active at a given time. NR also supports a so-called supplementary UL (SUL), on which UL BWP(s) can be similarly configured as on a normal UL. For paired spectrum, i.e., frequency division duplex (FDD), DL BWPs and UL BWPs are configured separately. For unpaired spectrum, i.e., time division duplex (TDD), a DL BWP is linked to an UL BWP when the indices of the two BWPs are the same. In this case, the paired DL BWP and UL BWP must share the same center frequency, but they can have different bandwidths. In general, a UE only receives physical downlink shared channel (PDSCH), physical downlink control channel (PDCCH), or channel state information reference signal (CSI- RS) inside an active DL BWP. But the UE may need to perform radio resource management (RRM) measurements outside the active DL BWP via measurement gaps. Similarly, the UE only transmits physical uplink shared channel (PUSCH) or physical uplink control channel (PUCCH) inside an active UL BWP and, for an active serving cell, the UE does not transmit sounding reference signal (SRS) outside an active UL BWP.

[0017] Bandwidth Part Types

[0018] Activating an inactive BWP and deactivating an active BWP are called BWP switching to enforce that it is not possible to deactivate all BWPs or to activate more than one. For paired spectrum, DL BWPs and UL BWPs can be switched separately. For unpaired spectrum, the paired DL BWP and UL BWP are switched together.

[0019] Initial DL / UL BWP: The initial DL and UL BWPs are used at least for initial access before radio resource control (RRC) connection is established. An initial BWP has index zero and is referred to as BWP #0. During the initial access, the UE performs cell search based on synchronization signal block (SSB) composed of primary synchronization signal (PSS), secondary synchronization signal (SSS), and physical broadcast channel (PBCH). To access the system, the UE needs to further read system information block 1 (SIB1 ) which carries important information including the initial DL / UL BWP configuration. The SIB1 is transmitted on the PDSCH, which is scheduled by downlink control information (DCI) on the PDCCH using the control resource set with index zero (CORESET #0). Before the UE reads the SIB1 , the UE’s initial DL BWP has the same frequency range and numerology as those of CORESET#0. After reading the SIB1 , the UE follows the initial DL / UL BWP configuration in the SIB1 and uses them to carry out a random-access procedure to request the setup of RRC connection. The network should configure the frequency domain location and bandwidth of the initial DL BWP in the SIB1 so that the initial DL BWP contains the entire CORESET #0 in the frequency domain.

[0020] First active DL / UL BWP: The first active DL and UL BWPs may be configured for a Special Cell (SpCell) or a secondary cell (SCell). In a master cell group (MCG), the SpCell refers to the primary cell (PCell) in which the UE 3 performs the connection (reestablishment procedure. In a secondary cell group (SCG), the SpCell refers to the primary SCG cell (PSCell) in which the UE performs random access for RRC (re)configuration. An SCell provides additional radio resources on top of an SpCell in a cell group. The first active DL and UL BWPs are the active DL and UL BWPs upon RRC (re)configuration for an SpCell or activation of an SCell.

[0021] Default BWP: For a serving cell, the network may configure the UE with a BWP inactivity timer. The expiration of this timer may, for example, indicate that the UE has no scheduled transmission and reception for a while on the currently active BWP. Thus, the UE can switch its active BWP to a default BWP to save power. The default DL BWP can be configured. If not configured, the UE uses the initial DL BWP as the default DL BWP. For unpaired spectrum, when the UE switches its active DL BWP to the default DL BWP, the active UL BWP is switched accordingly since the BWP switching for TDD is common for both DL and UL. The UE first performs downlink synchronization and acquires PBCH based on 20-RB SSB. Assuming the CORESET#0 configured in the MIB has 24 RBs, the UE may assume that the initial DL BWP is 24 RBs wide and proceeds to acquire SIB1 , which in this example also configures 24 RBs for both initial DL and UL BWPs. The UE then performs a randomaccess procedure with the small initial DL and UL BWPs. After the random access, the UE reports that it is capable of supporting multiple BWPs. With dedicated RRC signaling, the network configures the UE with large DL / UL BWP #1 (270 RBs), small DL / UL BWP#2 (52 RBs), and BWP inactivity timer. The network sets the large DL / UL BWP #1 as the first active DL / UL BWP, and the small DL BWP #2 as the default DL BWP. Upon RRC configuration, the first active DL and UL BWPs (i . e. , DL / UL BWP #1 ) become activated and are used for scheduling a large amount of data. After that, the UE does not have traffic demand and has no scheduled transmission. As a result, the BWP inactivity timer expires, upon which the UE switches its active DL BWP to the default DL BWP (i.e., DL BWP #2). Note that the active UL BWP does not need to switch to UL BWP #2, because Figure 2 illustrates an FDD system in which DL and UL BWPs are switched separately.

[0022] Another BWP types of definition from resources 4:

[0023] Initial BWP: common to all UEs; broadcast in System Information (SI) to be used for initial access, until UE receives BWP cell configuration. Possible sizes are 24, 48, or 96 PRBs.

[0024] First active BWP: a BWP activated upon Radio Resource Control (RRC) (re)configuration or MAC-activation of a Secondary Cell (SCell);

[0025] Default BWP: BWP activated upon the expiration of the BWP Inactivity Timer. Default BWP can occupy the same PRBs as the Initial BWP, and UEs are expected to stay in Default BWP until traffic demands increase; Dedicated BWP: regular BWP configured in a dedicated manner; usually is wider than Default BWP, as to allow transmission of higher traffic loads;

[0026] Bandwidth Parts Switch

[0027] Reconfiguration Based Bandwidth Parts Switch: When more than one UE-specific DL / UL BWPs are configured to the UE on a serving cell, the first active DL / UL BWP, if configured, indicates the DL / UL BWP to be activated upon RRC (re)configuration for an SpCell, and upon activation of an SCell. If the first active BWP is not configured, there is no BWP switch upon RRC (re)configuration. The first active DL / UL BWP is always configured upon SCell addition, upon PCell change in MCG, and PSCell addition or change in SCG. For BWP configuration Option 1 , switching from the initial DL / UL BWP to another DL / UL BWP requires RRC reconfiguration since only DCI format 1 _0 / 0_0 can be used with the initial DL / UL BWP without dedicated configuration which does not support the DCI-based BWP switch. For RRC-based BWP switch, there is a delay of receiving (for DL active BWP switch) or transmitting (for UL active BWP switch) on the new BWP on the serving cell after the UE receives RRC reconfiguration involving active BWP switch or parameter change of its active BWP. The delay requirement for RRC-based BWP switch, within which UE shall complete the switch of active DL and / or UL BWP, is the sum of processing delay for RRC procedure and the delay for UE to perform BWP switch. The processing delay requirements for RRC procedures are in the range of 5-80 ms (milliseconds) and differ among connection control procedures. The delay requirement for UE to perform RRC- based BWP switch is a few milliseconds.

[0028] DCI-Based Bandwidth Parts Switch: With initial DL / UL BWP and one or more additional DL / UL BWPs being configured to a UE, the network can schedule the UE to switch the active DL / UL BWP from one configured BWP to another using the BWP indicator in DCI format 1_1 / 0_1 . The possibility of DCI based BWP switch involving BWP #0 is dependent on BWP configuration option. DCI format 1_1 and DCI format 0_1 are non-fallback DCI formats for downlink assignment and uplink grant, respectively. They support the full set of NR features and their fields are largely configurable. On the other hand, fallback DCI formats 1_0 and 0_0, used respectively for downlink assignment and uplink grant, do not contain the BWP indicator field and thus do not support the DCI-based BWP switch. BWP field in DCI format 1_1 / 0_1 has the bit width of 0 - 2. The exact value is determined by the number of RRC configured DL / UL BWPs, excluding the initial DL / UL BWP. There is a transmission / reception delay between network and UE associated with DCI-based BWP switch. UE shall complete the switch of active DL and / or UL BWP within the required BWP switch delay. The switch delay denoted by TBWP switch Delay for DCI-based BWP switch is defined as the slot offset between the DL slot in which the UE received the switch request and the first slot in which the UE shall be able to receive PDSCH (for DL active BWP switch) or transmit PUSCH (for UL active BWP switch) on the new BWP. There are two levels of BWP switch delay requirement, type 1 and type 2, as given in Table 2. The UE is not required to transmit UL signals or receive DL signals during the time duration TBWP switch delay on the serving cell where DCI-based BWP switch occurs. Note that the BWP switch delay is dependent on SCS. If the BWP switch happens between BWPs of different SCS values, the switch delay requirement is determined by the smaller SCS.

[0029] Timer-Based Bandwidth Parts Switch: The network may configure a UE with a BWP inactivity timer and a default DL BWP on a serving cell. The default DL BWP is one of the DL BWPs configured to the UE and becomes the active DL BWP upon expiry of the inactivity timer. If no default DL BWP is configured, the default DL BWP is the initial DL BWP. For unpaired spectrum (TDD), a DL BWP and an UL BWP with the same indices are linked and switched together. Thus, a DL BWP is effectively a DL / UL BWP pair in this case. The granularity of the timer is 1 ms (i.e. , 1 subframe) for FR1 and 0.5 ms for FR2. When the timer is running, the UE decrements the timer at the end of each subframe for FR1 or at the end of each half-subframe for FR2. The values for the BWP inactivity timer have the range of 2 - 2560 ms. The maximum value for the BWP inactivity timer matches the maximum value of discontinuous reception (DRX) inactivity timer, which allows for a configuration that prevents the timer from expiring while the DRX inactivity timer is running. A UE starts the BWP inactivity timer of a serving cell, if configured, when it activates a DL BWP other than the default DL BWP. A UE restarts the BWP inactivity timer of the serving cell when it decodes a DCI with downlink assignment for the active DL BWP in paired spectrum, or when it decodes a DCI with downlink assignment or uplink grant for its active DL / UL BWP pair in unpaired spectrum. A UE shall start / restart the BWP inactivity timer when a PDCCH for DCI- based BWP switch is received. BWP inactivity timer can only be started or restarted when there is no ongoing random-access procedure associated with the serving cell. For a timer-based BWP switch, the BWP switch transition time duration is from the subframe / half-subframe for FR1 / FR2 immediately after a BWP inactivity timer expires until the beginning of a slot where the UE can receive or transmit. The UE is not required to receive or transmit on the serving cell during the transition. Timer-based BWP switch shares the same BWP switch delay requirements as DCI-based BWP switch.

[0030] Switching between configured BWPs may also happen when a random-access procedure is initiated on a serving cell. UL BWP is switched to the initial UL BWP if the physical random-access channel (PRACH) occasions are not configured for the active UL BWP of the serving cell. If the serving cell is SpCell, the active DL BWP needs to be switched to the one with the same BWP index as the active UL BWP.

[0031] Considering the mobility of base stations, the time that users can receive service from each satellite is limited. In addition, due to the wide coverage areas, many users receive service at the same time. Due to the high mobility of base stations and the large number of users receiving service, individual power saving techniques are applied. In addition, resource distribution for each user, assignment of BWPs and transitions between these BWPs cause additional processing intensity and delays.

[0032] The main technical problems are;

[0033] There are delays when users switch between the BWPs assigned to them. There are three types of BWP change methods:

[0034] 1 . RRCConfiguration

[0035] 2. Timer

[0036] 3. PDCCH

[0037] RRCConfiguration has the highest latency but it can be used to assign new BWPs. Timer and PDDCH based methods have almost the same latency and cause very low latency compared to RRCConfiguration. If a user is going to send or receive data, he / she changes his / her current BWP using these methods and returns to his / her old BWP after the operation is completed. This saves energy, but if this happens continuously, both signaling and latency increase.

[0038] All the problems mentioned above have made it necessary to make an innovation in the relevant technical field as a result.

[0039] BRIEF DESCRIPTION OF THE INVENTION

[0040] The present invention relates to a method to eliminate the above-mentioned disadvantages and bring new advantages to the relevant technical field.

[0041] The present invention relates to wireless communications, and more particularly, to a method for Orbit Aware BWP Adaptation of users with zones.

[0042] The invention basically proposes a method that provides a solution to the delays experienced by users when switching between BWPs assigned to users.

[0043] The purpose of this invention is to deal with users as a group, distribute resources collectively and assign group-specific BWPs, instead of configuring BWPs by distributing resources to users one-on-one, considering the mobility of satellite base stations.

[0044] Another main object of the invention is providing a method that is to increase the energy savings of the group as well as trying to reduce latency in BWP adaptation.

[0045] The invention provides a method that prevents users from changing BWP according to users individual needs (what is meant to be expressed by the need is actually high size data transfer). If the user receives large data, the user switches to a wider BWP. If there is no data transfer, the user switches to a narrower BWP to save energy) and only changes BWP as a group at certain periods, reducing the amount of delay and eliminating the need for extra processing power for optimization. The method provides that energy saving and processing power and reduces delay by simultaneously assigning BWPs to determined regions according to the group's needs in user communication with satellites.

[0046] In the invention, common BWPs can be assigned to groups and some restrictions are required to switch to these BWPs.

[0047] In the invention, the amount of delay is reduced by preventing users from changing BWP according to their individual needs and allowing them to change BWP only as a group at certain periods. In this way, no extra processing power is needed for optimization. In this case, there is a trade-off between total energy savings and processing power. Thus, the invention aims to increase the energy savings of the group as well as trying to reduce the delay.

[0048] With the invention, power savings can be achieved throughout the group. In addition, since resource allocation for each user, assignment of BWPs, and transitions between these BWPs cause additional processing intensity and delays, therefore, in some cases, delay reduction is chosen by avoiding individual power savings.

[0049] The invention is recommended preferably for high mobility LEO satellite as a base station.

[0050] Due to the high mobility and wide coverage areas of base stations (for example, LEO satellites etc.), instead of assigning BWP to each user individually, BWP is assigned to regions simultaneously. In this way, even if any user cannot save energy, when the entire system is considered, the amount of energy savings increases and processing power is saved, thanks to the invention.

[0051] By looking at the needs of the group rather than the individual needs of the users, there is no delay when a user changes the bandwidth, and since the BWP is assigned according to the needs of the group, even if a user in the group individually needs a wide BWP, if the group's need is low, a narrow BWP is assigned to save energy as a group enables it to be done. In this way, a decrease in latency, an increase in energy savings and a decrease in the required processing power are achieved.

[0052] The invention proposes a novel of reducing the amount of delay by preventing users from changing BWP according to user’s individual needs and allowing as a group to change BWP at certain periods.

[0053] Group: Since BWP will be assigned in certain periods, when the appointment time comes, it can be considered as all users within the coverage area of the satellite. And also, group can be defined only users registered to a certain type of service.

[0054] When the aim is saving energy in the invention that cannot guarantee that users will definitely transmit data, so users whose data is a priority may be harmed by this type of distribution. For this reason, there may be thousands of sensors measuring temperature in an agricultural area. Individual assignments can be made to other users in that region and distribution can be made to this sensor group with this invention.

[0055] Advantages of the invention:

[0056] • Energy saving when all users are considered,

[0057] • Saving processing power because the needs of the group are taken care of instead of dealing with the needs of each user individually.

[0058] • Reducing the signaling burden that would occur when dealing with each user individually (for example, when assigning a BWP or switching between existing BWPs) because all groups are dealt with at the same time in this method.

[0059] • Reducing delays occurring during BWP changes, which are problems in the previous technique, with the method presented in the invention, the delays experienced by individual users are reduced by enabling all users to change BWP at the same time.

[0060] Since the invention considers the needs of the group rather than the individual needs of the users, the delay caused by each user changing the bandwidth part is eliminated.

[0061] Another possible embodiment of the invention is characterized in that; a new switching method by combining Timer-Based and DCI-Based switching methods. The classification of virtual zones as a result of each adaptation period and the switching of the users in these zones to the new predetermined BWP is in fact the switching method of the present invention.

[0062] Embodiments of the invention;

[0063] • The method wherein said base station is mobile base station.

[0064] • The method wherein said base station is Leo satellite. The method in which the base station in question is a base station that knows which location each cell corresponds to and which cell each user receives service from.

[0065] ® The method wherein said determining virtual zone according to location information which is provided by GPS or using base station information related to known location.

[0066] The proposed method for bandwidth part adaptation is dependent on the computer implemented method. The method which can be executed by an apparatus for wireless communication at a base station in a wireless communications system (the apparatus may include a processor, memory coupled with the processor, and instructions stored in the memory), or a network device, or by a component of the network device (such as a processor, a chip, or a chip system, etc.), or can be implemented by all or logical modules or software implementations of some network device functions or computer implemented device.

[0067] Other aspects, features, and embodiments will become apparent to those of ordinary skill in the art, upon reviewing the following description of specific, exemplary aspects in conjunction with the accompanying figures. While features may be discussed relative to certain aspects and figures below, all aspects can include one or more of the advantageous features discussed herein. In other words, while one or more aspects may be discussed as having certain advantageous features, one or more of such features may also be used in accordance with the various aspects discussed herein. Such exemplary aspects can be implemented in various devices, systems, and methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0068] The present disclosure, in accordance with one or more various examples, is described in detail with reference to the following figures. The drawings are provided for purposes of illustration only and merely depict examples of the disclosure. These drawings are provided to facilitate the reader's understanding of the disclosure and should not be considered limiting the breadth, scope, or applicability of the disclosure. It should be noted that for clarity and ease of illustration these drawings are not necessarily made to scale.

[0069] Figure 1 . Virtual Zones with Different Sizes and Numbers

[0070] Figure 2. Standard BWP Adaptation for Different Users (Prior Art)

[0071] Figure 3. Novel BWP Adaptation for All Users in the Same Zone

[0072] REFERENCE NUMBERS GIVEN IN THE FIGURE

[0073] The reference numbers of the elements included in the figures are explained below.

[0074] 1 Number of rings:2

[0075] 2 Number of rings:3

[0076] 3 Number of rings:4

[0077] DETAILED DESCRIPTION OF THE INVENTION

[0078] In this detailed description, the subject matter is explained with references to examples without forming any restrictive effect only to make the subject more understandable. To achieve all the objectives mentioned above and that will emerge from the following detailed description.

[0079] The present invention relates to a method for orbit aware BWP adaptation of users with zones for that reduces the delay that occurs when the user changes the bandwidth part.

[0080] The invention is for high mobility satellite base stations preferably LEO satellite (base station can be HAPS etc.). Considering the mobility of base stations, the time that users can receive service from each satellite is limited. In addition, due to wide coverage areas, a high number of users receive service at the same time. Due to the high mobility of base stations and the large number of users receiving services, it may be more logical to focus on power saving occurring in an entire group rather than individual power saving techniques. In addition, resource distribution for each user, assignment of BWPs, and transitions between these BWPs cause additional processing intensity and delays. For this reason, in some cases, latency reduction can be chosen by avoiding individual power saving.

[0081] The method that saves energy, processing power and reduces delay by simultaneously assigning BWPs to determined regions according to the group’s needs in the user's communication with satellites base station has been described.

[0082] In this invention, BWP adaptation is done for all users in a region instead of being done separately for each user. Novel BWP Adaptation for All Users in the Same Zone is illustrated in figure 3. Initial BWP, adaptation periods, power saving BWP, burst BWP and standard BWP are shown as a frequency-time graph in figure 3.

[0083] The satellite's coverage area is divided into virtual zones. These virtual regions should not be thought of as cells. The shape and number of virtual zones may vary depending on the type of operation and equipment capability. Increasing the number of regions provides a more reliable classification of regions but increases the processing load. If the number of regions is reduced, the processing load decreases, but reliability decreases when the regions are classified. Regions are classified at certain intervals. While making this classification, information such as the bandwidths that will be used as a result of resource allocation, the amount of data to be distributed to users, and how long the satellite will remain visible to users are used. This classification is made separately for each region. Since the satellite is in motion, it moves in virtual regions within the satellite's coverage area. In other words, when classifying in a certain period, only the information belonging to the users in each region at that moment is used. There are three types of zones:

[0084] Power Saving Zone: The amount of data to be distributed to users in this region is small and the time that the satellite will remain visible to users in this region is more than sufficient. All users in this region use a narrow BWP. Standard Zone: The amount of data to be distributed to users in this region is average and the time that the satellite will remain visible to users in this region is sufficient. All users in this region use a medium-width BWP.

[0085] Burst Zone: The amount of data to be distributed to users in this region is large and the time that the satellite will remain visible to users in this region is limited. All users in this region use a broad BWP.

[0086] After the regions are classified, the order to use BWP for that region is sent to all users within that region. If a user who will receive a large amount of data and a user who will receive a small amount of data fall into the power saving zone, both will use a narrow BWP. In current standards, each user can be configured with four different BWPs, provided that only one is active at a time. These are initial BWP, first-active BWP, default BWP and dedicated BWP. There is the same logic for the bandwidths assigned to zones, but there are serious width differences between the bandwidths assigned to each zone type. In this way, resource economy is not compromised except in serious cases.

[0087] Adaptation Period: The adaptation period determines the interval in which all virtual regions will be classified. The adaptation period is variable. After determining how long users will see the satellite on average for all regions, the remaining visibility time of the region with the minimum average is used as a timer for the next classification time. It is known that BWP switching causes different amounts of delay depending on different switch types. By preventing frequent switching with the adaptation period, the amount of latency that occurs during switching is also reduced. It can be considered similar to the currently used Timer-Based Switching method, but here, users are informed via physical downlink control channel (PDCCH) signaling while the timer is running on the base station.

[0088] The method of the invention provides to enable all users to change Bandwidth Part (BWP) at the same time, thereby reducing the delays experienced by individual users. The invention proposes reducing the amount of delay preventing users from changing BWP according to their individual needs and allowing them to switch BWP only as a group at certain periods.

[0089] Thanks to these different BandwithBWPs, users can increase their data rates by using a wider BWP when needed, while when not needed, users can switch to a narrower BWP to save power. However, there is a delay during these switches. The amount of this delay varies depending on the switching technique used.

[0090] The invention is providing to deal with users as a group, distribute resources collectively and assign group-specific BWPs, instead of configuring BWPs by distributing resources to users one-on-one, considering the mobility of satellite base stations. In this way, since all users in a group will be forced to use the same BWP, there will be an increase in power saving. In addition, it is to minimize the switching delay by making the transition between the BWPs in which these groups will be configured at certain periods and entering into a tradeoff with power saving in certain cases.

[0091] Since the idea basically enables the community to save energy, it may cause individual losses on energy. For this reason, a hybrid method can be developed by using it together with the BWP method found in the standards.

[0092] In order for the invention to be implemented that is sufficient to have at least one LEO satellite (base station) and a high number of users. Number of users vary depending on many factors. For example, the altitude at which the LEO satellite is located will affect its speed. Two satellites with the same equipment will have different coverage areas at different altitudes. The speed and coverage area of the satellite will affect how long users will receive service. So that user numbers can be 10000 users may be sufficient for a fast satellite with a small coverage area or user numbers can be 100000 users will only be sufficient for a relatively slow satellite with a larger coverage area. All in all, these user numbers are not limited to 1000 or 100000, it depends on speed and coverage area of satellite. LEO base station (providing services to users in the area and undertaking tasks such as BWP assignment and distribution).

[0093] A computer implemented method for Orbit Aware orbit aware bandwidth part (BWP) adaptation of users which is suitable for being used within a communication network comprising

[0094] # At least one base station,

[0095] • Users which receive service from base stations according to speed of base station and coverage area, characterized in that the method comprises the steps of; a. Waking up users for receiving the service according to connected-mode discontinuous Reception (C-DRX) periods, b. Obtaining access time-dependent coordinate information of the incoming satellite using their ephemeris data information by users, c. Initiating random access procedures by scanning the physical channel within the initial BWP by each user, d. Determining zones preferably virtual zone which user is located in, e. Classifying regions preferably virtual regions using the bandwidths determined by resource distribution, f. Calculating total data distribution time regardless of whichever bandwidth is used when categorizing the regions, comparing the calculated total data distribution time with the remaining visibility time of the satellite, g. Sending first active BWP information to all users in the coverage area after radio resource control (RRC) signal, h. Determining the remaining visibility duration of the region with the minimum average by using the information on how long the base station will last on average for each previously determined region, i. Comparing visibility times of the region to obtain minimum time as an adaptation period, j. Starting countdown at the base station as a timer for repeating zone classification at variable periods until the next classification, k. After the timer passes, learning again in which virtual zone each user will be located by the base station, l. Determining the average length of time the base station will remain visible to users for each region and determining the amount of data to be distributed to users in the region again and continuing with step f.

[0096] Some detailed explanations of the steps involved in the method are given below.

[0097] 1 .Waking up users according to C-DRX (Connected-mode Discontinuous Reception) periods. (Users can use an orbit-aware DRX structure.) C-DRX is known in literature. There is an asleep and wake-up routine, and this routine is repeated at a certain period. In this case, the user group that will receive the service wakes up when a satellite enters their field of view. Satellites move deterministically, so they have a certain period.

[0098] 2. Obtaining access time-dependent coordinate information of the incoming satellite using their ephemeris data information by users.

[0099] 3. Initiating random access procedures by scanning the physical channel within the initial BWP by each user.

[0100] 4. Determining zones preferably virtual zone which user is located in. The base station learns which virtual zone each user is located in. There are two ways to learn location information. One can be used GPS, the other one using base station information. GPS sourced location information can be used here. Additionally, the LEO base station provides cellular service. (The cell is about here is not a virtual zone.) The base station can know which location each cell corresponds to. In addition, since it knows which cell each user receives a service from, the base station can determine the user location even if it is not in high resolution. The second method will provide an extra advantage, especially in cases where the virtual zone and the cellular structure where the service is provided overlap. Because transmitting GPS-based location information can be considered as creating an additional signaling burden. For each region, the average length of time the base station will remain visible and the amount of data to be distributed to users in the region is determined.

[0101] In order to group users, their locations must be known. The LEO base station can already know its own location, the position of its cells on the ground and its own speed. How users' locations can be determined is explained in the previous section. We can say that it calculates how long it will remain visible on average by calculating the average distance / time for the users it groups. Additionally, for grouping, the amount of data to be distributed to users should be considered. High size data needs to be transferred to users. It is calculated how long it takes to transfer this data. Different methods can be used for calculation, but it can also think of it as a simple process such as distance / time calculation.

[0102] 5. In addition to the user-virtual region information in the previous step, classifying regions preferably virtual regions using the bandwidths determined by resource distribution. Virtual regions begin to be classified using the bandwidths determined by resource distribution.

[0103] 6. Calculating total data distribution time regardless of whichever bandwidth is used when categorizing the regions, comparing the calculated total data distribution time with the remaining visibility time of the satellite( Here, the users entering these zones change as the satellite moves. In other words, as the users entering that zone change, the total amount of data at that moment also changes. For this reason, how long it will take to transmit the total amount of data needs to be calculated over and over again with the same period.). How long the total data distribution will take is calculated and this time is compared with the remaining visibility time of the satellite and sufficient minimum bandwidth is selected. With information about how long the total data distribution takes, how long the satellite is visible, and what conditions are met, the local minimum bandwidth selection condition can be explained as follows: Let there be 2000 users at time t in any virtual zone. Let x be the total amount of data to be distributed to these 2000 users. There are three different types of virtual zones, that is, BWPs with three different widths. Calculation of how long it will take to transfer the amount of data x can be calculated for three different BWPs. For example, there are narrow, medium and wide BWPs. Let it take 17 seconds to transfer this amount of data x when using narrow BWP, 12 seconds when using medium BWP, and 6 seconds when using wide BWP. However, users in that virtual zone will be able to see the satellite until t +15. If narrow BWP is used, the satellite will no longer be visible before the data transfer is completed. When large BWP is used, the transfer will take a very short time, but they will not be able to save energy because they will continue to use that BWP until the next virtual zone distribution. In this case they need to use the medium sized BWP. In short, the time taken for data transfer should be < the visibility time of the satellite. As the BWP width increases, the time taken for data transfer will decrease, but the amount of energy savings will decrease, so the minimum BWP that will meet this condition must be selected. Instead of directly comparing two values, a margin of error can be added.

[0104] 7.With RRCConfiguration (radio resource control (RRC) Configuration), in addition to the BWP information to be used for these three zone types, which BWP will be used first is sent to each user immediately after the RRCConfiguration signal, since the first classification is made. The reason why the first BWP information to be used is sent to each user is that already used in the standard method. Therefore, with RRCConfiguration, the First Active BWP information that will be used after the Initial BWP is sent to the user.

[0105] 8. Using the information on how long the base station will last on average for each previously determined region, the remaining visibility time of the region with the minimum average is determined as the adaptation period, and the countdown begins at the base station as the timer until the next classification. Users' locations are known. As a result of grouping, it is also known which user is included in which group. For each group, on average, it is calculated how long the satellite will remain visible. When all these visibility times are compared, the minimum time is determined as the adaptation period and the timer is started.

[0106] 9.After the timer passes, the base station learns again in which virtual zone each user will be located. For each region, the average length of time the base station will remain visible to users and the amount of data to be distributed to users in the region is determined again and continue with step 6. A timer is needed to repeat zone classification at variable periods. In the BWP distribution method in the standards, the timer mechanism is used as a BWP change tool. In order to comply with current standards, the timer mechanism is also included in this idea, but it works jointly for all users, not specifically for each user.

[0107] Simulation:

[0108] Simulation Parameters

[0109] Number of Users: 100000

[0110] Number of Users with Large Data Size: 20000

[0111] Number of Users with Average Data Size: 10000

[0112] Number of Users with Small Data Size: 80000 User Distribution: Uniform

[0113] Satellite Altitude: 500 km

[0114] Satellite Coverage Area Radius: 375 km

[0115] Number of Zones: 37

[0116] Table 1. BWP Adaptation Zones Power Saving Simulation Results for Given Parameters

[0117] (3GPP 38.840 - Study on User Equipment (UE) power saving in NR) The improvement in power saving is according to the aforementioned invention vs. standard BWP method.

[0118] The scope of protection of the invention is specified in the attached claims and cannot be limited to those explained for sampling purposes in this detailed description. It is evident that a person skilled in the art may exhibit similar embodiments in light of the above-mentioned facts without drifting apart from the main theme of the invention.

Claims

CLAIMS1. A computer implemented method for orbit aware bandwidth part (BWP) adaptation of users which is suitable for being used within a communication network comprising• At least one base station,• Users which receive service from base stations according to speed of base station and coverage area, characterized in that the method comprises the steps of; a. Waking up users for receiving the service according to connected-mode discontinuous reception periods, b. Obtaining access time-dependent coordinate information of the incoming satellite using their ephemeris data information by users, c. Initiating random access procedures by scanning the physical channel within the initial BWP by each user, d. Determining zones preferably virtual zones which user is located in, e. Classifying regions preferably virtual regions using the bandwidths determined by resource distribution, f. Calculating total data distribution time regardless of whichever bandwidth is used when categorizing the regions, comparing the calculated total data distribution time with the remaining visibility time of the satellite, g. Sending first active BWP information to all users in the coverage area after radio resource control (RRC) signal, h. Determining the remaining visibility duration of the region with the minimum average by using the information on how long the base station will last on average for each previously determined region, i. Comparing visibility times of the region to obtain minimum time as an adaptation period, j. Starting countdown at the base station as a timer for repeating zone classification at variable periods until the next classification, k. After the timer passes, learning again in which virtual zone each user will be located by the base station,I. Determining the average length of time the base station will remain visible to users for each region and determining the amount of data to be distributed to users in the region again and continuing with step f.

2. The method according to claim 1 , wherein said base station is mobile base station.

3. The method according to claim 1 or claim 2, wherein said base station is Leo satellite.

4. The method according to claim 1 , wherein said base station is a base station that knows which location each cell corresponds to and which cell each user receives service from.

5. The method according to claim 1 , wherein said determining virtual zone according to location information which is provided by GPS or using base station information related to known location.

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