Random access method based on beam forming in NTN, base station equipment and user terminal

Abstract

The invention discloses a random access method based on beam forming in NTN, base station equipment and a user terminal. The method executed by the NTN base station comprises the following steps: acquiring a beam position planning parameter in a coverage area, and determining reference point configuration in a beam position based on the beam position planning parameter and a preset reference point mapping rule; sending system messages for different wave positions, wherein the system messages carry the position information of the current wave position and the reference point configuration; and a first signal sent by the user terminal in the random access process is received, a target reference point is determined according to the random access resource used by the first signal, beam forming is performed based on the position of the target reference point, and random access with the user terminal is completed. According to the scheme of the invention, on the basis that a traditional 5G system selects PRACH (Physical Random Access Channel) association and preamble based on SSB, a geographical position-based selection mechanism is introduced to realize beam forming in a random access process, and the success rate of UE random access is improved.

Description

Technical Field

[0001] This invention relates to the field of satellite communication technology, and in particular to a beamforming-based random access method, base station equipment, and user terminal in NTN. Background Technology

[0002] When 5G NR operates in a massive MIMO scenario, it employs beamforming technology. The network side uses multiple beams to cover different directions. The SSB (Synchronization Signal Block) index for each downlink direction represents a specific beam direction, such as... Figure 1 As shown. Simultaneously, during the random access process, each SSB index is also mapped to a specific set of PRACH (Physical Random Access Channel) occasions. When the UE (user terminal) detects a certain SSB beam, it selects the PRACH occasion corresponding to that SSB index to send the random access preamble, such as... Figure 2 As shown, the base station can deduce the UE's location based on the received PRACH, and then perform beamforming in the corresponding direction during subsequent random access.

[0003] In existing 5G NTN (Non-Terrestrial Network) scenarios, satellite coverage areas are close to a two-dimensional plane. To facilitate unified planning of coverage areas, the ground is divided into multiple bands, each corresponding to an SSB index. Because a band has a vast area—for example, at a satellite altitude of 500km, the band radius can reach 50km—the coverage area of ​​a band is much larger than the cell range in a conventional terrestrial network. If the mapping relationship between the SSB index, PRACHocccasion, and preamble used in traditional terrestrial networks is applied, the UE's location can only be roughly determined to the β band level, failing to obtain more accurate coordinates. Before random access is completed, the UE cannot report its own location. Therefore, during random access, the base station can only perform angle calculations based on a certain strategy. Excessive deviation between the beam direction and the UE's location reduces the access success rate and may also increase inter-beam interference. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a beamforming-based random access scheme in NTN, enabling the base station to obtain a more accurate location of the UE, thereby optimizing the beam direction during the random access process and improving the access success rate.

[0005] The present invention solves the above-mentioned technical problems through the following aspects: A first aspect of the present invention provides a beamforming-based random access method in an NTN, executed by an NTN base station, the method comprising: Obtain the wave position planning parameters within the coverage area; Based on the wave position planning parameters and the preset reference point mapping rules, the configuration of reference points within the wave position is determined; System messages are sent for different wavelengths, carrying the current wavelength's position information and the reference point configuration; The system receives a first signal sent by a user terminal during random access and determines a target reference point based on the random access resources used by the first signal. The first signal is generated by the user terminal after selecting a target reference point based on its own location, the position information of the wave position carried in the system message, and the reference point configuration, and then using the random access resources corresponding to the target reference point. Beamforming is performed based on the location of the target reference point to complete random access with the user terminal.

[0006] A second aspect of the present invention provides a beamforming-based random access method in an NTN, executed by a user terminal, the method comprising: Determine the geographical location of the user terminal itself; The system receives and parses system messages sent by the base station for different wavelengths, and obtains the current wavelength location information and reference point configuration carried therein; the reference point configuration is determined by the base station according to the wavelength planning parameters within the coverage area and the preset reference point mapping rules; The target reference point is determined based on its own geographical location, the position information of the wave position, and the configuration of the reference point. During the random access process, a first signal is generated using the random access resources corresponding to the target reference point and sent to the base station, so that the base station can determine the target reference point based on the random access resources used by the first signal, and perform beamforming based on the position of the target reference point to complete the random access process.

[0007] A third aspect of the present invention provides an NTN base station device, comprising: Wave position parameter acquisition module, used to acquire the planning parameters of wave position within the coverage area; The configuration management module is used to determine the reference point configuration within the wave position based on preset reference point mapping rules; The system message processing module is used to generate and send system messages for different wave positions, which carry the position information of the current wave position and the reference point configuration; The signal receiving and determining module is used to receive a first signal sent by the user terminal during random access, and to determine the target reference point selected by the user terminal based on the random access resources used by the first signal; the first signal is generated by the user terminal after selecting the target reference point based on its own location, the position information of the wave position carried in the system message and the reference point configuration, and then using the random access resources corresponding to the target reference point. The beamforming control module is used to perform beamforming based on the position of the target reference point and to complete random access with the user terminal.

[0008] A fourth aspect of the present invention provides an NTN user terminal, comprising: The positioning module is used to determine the geographical location of the user terminal itself; The system message parsing module is used to receive and parse system messages sent by the base station for different wavelengths, and obtain the current wavelength location information and reference point configuration carried therein; the reference point configuration is determined by the base station according to the wavelength planning parameters within the coverage area and the preset reference point mapping rules; The reference point determination module is used to determine the target reference point based on its own geographical location, the position information of the wave position, and the reference point configuration. The random access module is used to generate a first signal using the random access resources corresponding to the target reference point during the random access process and send it to the base station, so that the base station can determine the target reference point based on the random access resources used by the first signal and perform beamforming based on the position of the target reference point to complete the random access process.

[0009] The random access scheme of this invention introduces a geolocation-based selection mechanism to achieve beamforming during the random access process, building upon the traditional 5G system's selection of PRACH occasion and preamble based on SSB. In this scheme, multiple reference points are mapped within a beam position, with each reference point corresponding to a different PRACH occasion and preamble. The parameters of the reference points can be sent via beam position-level system messages. In this scenario, the UE can select the PRACH occasion and preamble corresponding to the nearest reference point to send the PRACH. The NTN base station can then determine which reference point within the beam position the UE is near based on the received PRACH, and thus adopt the beamforming angle for the corresponding sub-region, thereby improving the success rate of UE random access. Attached Figure Description

[0010] Other features, objects, and advantages of this disclosure will become more apparent from the following detailed description of non-limiting embodiments, taken in conjunction with the accompanying drawings. In the drawings: Figure 1 This is a schematic diagram showing the temporal arrangement of SSBs and their correspondence with beams in 5G NR. Figure 2 This is a schematic diagram illustrating the mapping between SSB indexes and PRACH occasions and preambles in 5G NR. Figure 3 This is a schematic diagram of the mapping between ground wave positions and SSB indexes in the existing NTN; Figure 4 A schematic diagram showing the deviation of the beamforming angle from the UE in an existing NTN; Figure 5 A flowchart of a random access method performed on the base station side as provided in an embodiment of this disclosure; Figure 6 This is a schematic diagram of the reference point distribution method in an embodiment of this disclosure; Figure 7 This is a schematic diagram illustrating the mapping relationship between the SSB index and PRACH occasion and preamble in an embodiment of this disclosure; Figure 8 This is a schematic diagram illustrating the UE selecting PRACH resources based on a reference point in an embodiment of this disclosure; Figure 9 This is a schematic diagram of beamforming performed by the base station based on a reference point in an embodiment of this disclosure; Figure 10 This is a flowchart illustrating the beamforming-based random access method executed by a user terminal in an embodiment of this disclosure. Figure 11 A schematic diagram of the signaling flow for implementing the random access method disclosed herein; Figure 12 A structural block diagram of a base station device is provided for embodiments of this disclosure; Figure 13 This is a structural block diagram of a user terminal provided in an embodiment of the present disclosure; Figure 14 This is a schematic diagram of the module structure of a base station and a terminal provided in another embodiment of this disclosure. Detailed Implementation

[0011] To enable those skilled in the art to better understand the technical solutions of this disclosure, the technical solutions of this disclosure will be clearly and completely described below with reference to the accompanying drawings of the embodiments of this disclosure. Obviously, the described embodiments are merely some embodiments of this disclosure, and not all embodiments. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this disclosure. Furthermore, for clarity, parts unrelated to the described exemplary embodiments have been omitted from the drawings.

[0012] In this specification, it should be understood that terms such as "comprising" or "having" are intended to indicate the presence of features, figures, steps, behaviors, components, portions, or combinations thereof disclosed herein, and are not intended to exclude the possibility of one or more other features, figures, steps, behaviors, components, portions, or combinations thereof being present or added. It should also be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other.

[0013] In 5G NTN scenarios, the coverage area of ​​a satellite is close to a two-dimensional plane. To achieve unified coverage planning, the ground area is divided into multiple beam positions. These beam positions are typically bound to geographical locations, meaning that a certain number of beam positions are contained within the coverage area of ​​a satellite base station. If the correspondence between the SSB index and beam angle of the terrestrial network is applied to NTN, then each ground beam position will correspond to an SSB index. This correspondence is as follows: Figure 3 As shown.

[0014] The planning of ground preambles is related to satellite altitude and coverage angle. Generally, the higher the satellite altitude, the wider the coverage angle, and the larger the corresponding ground coverage area. To ensure a one-to-one mapping between SSB indices and ground preambles, the planned preamble area is relatively large when the number of SSB indices is limited. Taking a satellite at an altitude of 500km as an example, if its coverage angle is ±50°, its ground coverage radius is approximately 660km. Planning with one preamble per 50km radius would require approximately 200 preambles to completely cover the area.

[0015] Due to the correspondence between the SSB index and the PRACH occasion and preamble, as well as the mapping between the SSB index and the wavelet position, the PRACH occasion and preamble set used by users within a wavelet position are consistent. Therefore, the spaceborne NTN base station can determine the wavelet position of the user based on the received PRACH sent by the user. In the subsequent random access process, the beamforming of the uplink and downlink physical channels for transmitting and receiving signals can only be performed based on angle calculations according to certain strategies, such as the wavelet position center position. Figure 4 As shown in the diagram. In this situation, because the area of ​​a single beamwidth is very large and the beamforming angle has a large deviation, the signal-to-noise ratio of the uplink and downlink physical channels will decrease significantly, thus affecting the user's access success rate.

[0016] Based on this, this disclosure introduces a location-based PRACH occasion and preamble selection mechanism for NTN coverage scenarios. This allows the NTN base station to determine the more accurate position of the terminal in the beamwidth when receiving the PRACH, thereby making the beamforming direction more accurate during subsequent random access, improving the received signal-to-noise ratio, and ultimately increasing the access success rate. Specific embodiments are described below.

[0017] Figure 5 This is a flowchart of the beamforming-based random access method executed on the base station side in an embodiment of this disclosure.

[0018] like Figure 5 As shown, the method in this embodiment includes steps S110 to S150, which are executed by the NTN base station.

[0019] S110: Obtain the wave position planning parameters within the coverage area. These parameters include the size and location of the wave position.

[0020] S120: Based on the wavelength planning parameters and preset reference point mapping rules, determine the reference configuration within the wavelength position. The reference point mapping rules define the location distribution of multiple reference points within the wavelength position, as well as the correspondence between each reference point and a set of random access resources. In each reference point location distribution method, the random access resources corresponding to any two reference points are not completely identical, thus enabling the base station to distinguish different reference points through the random access resources used by the UE.

[0021] S130: Sends system messages for different wave positions, carrying the current wave position's location information and reference point configuration. The wave position's location information can be the latitude and longitude of the wave position's center.

[0022] S140: Receive the first signal sent by the user terminal during the random access process, and determine the target reference point based on the random access resources used by the first signal. The first signal is generated by the user terminal after selecting the target reference point based on its own location, the position information of the wavelet carried in the system message, and the reference point configuration, and then using the random access resources corresponding to the target reference point.

[0023] S150: Beamforming is performed based on the location of the target reference point to complete random access with the user terminal.

[0024] In this embodiment, the wavefront planning parameters for the base station coverage area can be recorded using a wavefront database. Step S110 may involve obtaining the wavefront planning parameters within the coverage area from the wavefront database. The planning parameters mainly include the size and geographical location information of the wavefronts, and the latitude and longitude of the wavefront center can reflect the location of the wavefront. For example, if the ground coverage radius of a satellite is approximately 660 km, and the planned wavefront radius is 50 km, the wavefront database needs to record the center coordinates of approximately 200 wavefronts.

[0025] In this embodiment, the reference point mapping rules need to be pre-defined by the system. These rules define the location distribution of multiple reference points within a wavelength range, and the correspondence between each reference point and a set of random access resources. In each reference point location distribution pattern, different reference points are configured with different random access resources. Multiple location distribution patterns are identified by different serial numbers. According to the mapping rules, the reference point configuration determined by the base station includes the serial numbers of the regular or irregular distribution patterns of multiple reference points in a predetermined coordinate system, as well as the distance reference units in the predetermined coordinate system.

[0026] In some implementations, the multiple reference points are distributed in one of the following ways: N reference points are evenly distributed in a grid pattern in a Cartesian coordinate system, where N takes values ​​of at least 4 and 16; or M reference points are evenly distributed radially in a polar coordinate system, where M is an integer greater than 1. The Cartesian coordinate system can use east-west and north-south directions as coordinate axes, while the polar coordinate system uses the east-west direction as its coordinate axis. For example, Figure 6 (a) is an example of 4 reference points distributed in a rectangular coordinate system, which is similar to the constellation points of QPSK. (b) is an example of 16 reference points distributed in a rectangular coordinate system, which is similar to the constellation points of 16QAM. Figure 6 Example (c) shows a distribution of 6 reference points in polar coordinates, and example (d) shows a distribution of 19 reference points in polar coordinates. The distribution of multiple reference points can also take other forms, such as constellation point distribution similar to APSK, or unstructured or irregular distribution methods, as long as the system is pre-configured so that both the base station and the UE are aware of the distribution. Using a preset reference point distribution method can simplify the mapping relationship and reduce the amount of information transmitted by the base station. For example, the system has a total of preset reference point distribution methods. Figure 6 The four types shown can indicate the distribution of reference points within a wave position using only 2 bits of information.

[0027] The predefined reference point mapping rules define the random access resources corresponding to each reference point. These resources include the random access occasion (PRACH occasion) and the preamble. The number of reference points within a single wavelength cannot exceed the number of available preambles, thus allowing different reference points to correspond to different PRACH occasions and preambles. For example, assuming there are 16 available preambles within the current wavelength, and each wavelength has 4 reference points, the mapping relationship between the SSB index and the PRACH occasion and preamble can be designed as follows: Figure 7 As shown. In the first configuration cycle, SSB0 corresponds to occasion 0, SSB1 corresponds to occasion 1, SSB2 corresponds to occasion 2, and SSB3 corresponds to occasion 3. The 16 preambles are divided into 4 groups and assigned to 4 reference points. The first reference point uses group P0, corresponding to preambles 0-3; the second reference point uses group P1, corresponding to preambles 4-7; the third reference point uses group P2, corresponding to preambles 8-11; and the fourth reference point uses group P3, corresponding to preambles 12-15.

[0028] In this embodiment, the reference point configuration carried in the system message sent by the base station includes the distribution method of multiple reference points and the distance reference unit. The distance reference unit is used to define the actual geographical distance corresponding to one unit length in the coordinate system of the multiple reference points. The distribution method of the reference points can be selected from several preset methods of the system, such as... Figure 6 As shown, the base station can indicate the current reference point distribution method using only 2 bits of information. The purpose of the distance reference unit is to allow the UE to determine its distance from each reference point, facilitating the search for the nearest target reference point. The center coordinates of multiple reference points within the current waveform can be the center coordinates of the current waveform, and the distance reference unit can be the straight-line distance from the center point of the waveform to a preset reference point or the projected distance in a preset direction. For example... Figure 6 In this system, the reference point closest to the center point in the first quadrant is uniformly used as the preset reference point, and its ordinate value is used as the distance reference unit. In actual implementation, the preset reference point and preset direction can be set as needed. In step S130, the system message is obtained by recoding the SIB1 information generated by the system. This recoding operation avoids altering the original system-generated serving cell-level SIB1 information, reducing changes to the original system. The center coordinates, reference point distribution, and distance reference units are recoded with the original SIB1 information to generate a new system message, which is still transmitted over the original SIB1 physical channel. Since it includes the center coordinates of the current radii, it needs to be sent within the corresponding radii.

[0029] In step S140, the first signal sent by the UE is received; in a 5G system, this is the Msg1 message. Before random access, the UE has already completed its own positioning. At this point, the UE establishes a coordinate system based on the preset coordinate direction, using the center point carried in the system message as the origin. Then, according to the distribution of reference points and the distance reference unit, the positions of all reference points within the current band can be determined. The UE then calculates the nearest reference point and, based on the pre-set correspondence between reference points and random access resources, selects the corresponding PRACH occasion and preamble. The PRACH occasion and preamble are evenly distributed based on the set of PRACH occasions and preambles corresponding to the SSB, according to the number of reference points. Then, PRACH selection is performed within the resources corresponding to the currently selected target reference point, such as... Figure 8 As shown, the current wave position corresponds to SSB7, and there are 4 reference points. According to... Figure 7 Example of the correspondence between SSB and PRACH occasion: For SSB7, if the UE is closest to reference point 01, then the UE should select occasion 3 in the second PRACH configuration cycle, and the preamble should be selected from 4 to 7. Correspondingly, after receiving the PRACH, the NTN base station can determine the UE's beam position corresponding to SSB7 based on the selected PRACH occasion and preamble, and further determine that the UE is near reference point 01 at that beam position. Therefore, the beamforming of subsequent random access uplink and downlink physical channels will be directed towards the vicinity of reference point 01. This makes the transmit and receive links closer to the terminal location, thereby improving the access success rate. Figure 9 As shown.

[0030] The target reference point can be the reference point closest to the UE. If the UE calculates that it is the same distance from two or more reference points, it means that the UE is exactly in the middle of multiple reference points. At this time, the first nearest reference point can be selected as the target reference point according to a predetermined rule, such as clockwise.

[0031] In step S150, after determining the target reference point corresponding to the random access resources used by the UE, it can be determined that the UE is close to the target reference point. This allows for more accurate beam orientation during subsequent message transmission and reception in the random access process. The beam can point to the location of the target reference point or the geographic center of the sub-region corresponding to the target reference point. In some cases, the target reference point and the geographic center point coincide. A sub-region is an area where the reference point is located; it can be rectangular, triangular, or hexagonal, etc. Multiple sub-regions do not overlap. Figure 6 The areas separated by dashed lines in (c) and (d). Beamforming based on the target reference point's location can also direct the beam to the weight center location calculated from historical access data within the sub-region corresponding to that target reference point. The base station calculates in real-time the location with the highest historical UE access success rate and uses it as the weight center, thereby improving the access success rate. For example, if the reference point for a sub-region is the geographical center, but that location is obstructed by large buildings or mountains, resulting in a low historical access success rate, the beam can be directed to the location with the high access success rate.

[0032] This embodiment of the random access method introduces a geolocation-based selection mechanism to achieve beamforming during the random access process, building upon the traditional 5G system's selection of PRACH occasion and preamble based on SSB. The geographical location within a beam position is realized through multiple reference points mapped within that beam position. Each reference point corresponds to a different PRACH occasion and preamble. The parameters of the reference points are sent down via beam position-level system messages, allowing the UE to select the PRACH occasion and preamble corresponding to the nearest reference point to send the PRACH. The base station can determine which reference point within the beam position the UE is near based on the received PRACH, and thus adopt the beamforming angle for the corresponding sub-region, thereby improving the success rate of UE random access.

[0033] Corresponding to the base station-side method, this specification also provides a random access method performed by the user terminal.

[0034] Figure 10 This is a flowchart illustrating the execution of a beamforming-based random access method by a terminal in an embodiment of this disclosure.

[0035] like Figure 10 As shown, the method in this embodiment includes steps S210 to S240. This method is executed by the user terminal and works with the NTN base station to achieve beamforming in the random access process.

[0036] S210: Determine the geographical location of the user terminal itself.

[0037] S220: Receive and parse system messages sent by the base station for different wavelengths, obtaining the current wavelength's location information and reference point configuration carried within them. The reference point configuration is determined by the base station based on wavelength planning parameters within the coverage area and preset reference point mapping rules. The reference point mapping rules define the location distribution of multiple reference points within a wavelength, and the correspondence between each reference point and a set of random access resources. In each reference point location distribution method, different reference points are configured with different random access resources.

[0038] S230: Determine the distance to the target reference point based on its own geographical location, wave position information, and reference point configuration.

[0039] S240: During the random access process, a first signal is generated using the random access resources corresponding to the target reference point and sent to the base station so that the base station can determine the target reference point based on the random access resources used by the first signal and perform beamforming based on the position of the target reference point to complete the random access.

[0040] In this embodiment, the method for generating system messages and the method for setting reference point configuration can refer to the previous embodiment.

[0041] In this embodiment, after the base station determines the reference point configuration within the beamwidth, it notifies the UE through a beamwidth-level system message. The UE can then select the random access resource corresponding to the nearest reference point to send a PRACH. The base station can determine the nearest reference point to the UE within the beamwidth based on the received PRACH, and in the subsequent random access process, it adopts the beamforming angle corresponding to the reference point for transmitting and receiving signals, thereby improving the success rate of UE random access.

[0042] The following is through Figure 11 This describes the overall signaling process for implementing the beamforming-based random access method in the NTN disclosed herein.

[0043] like Figure 11 As shown, the gNB first obtains the beamfront planning parameters, including beamfront size and location. Based on the planning parameters and the preset reference point mapping relationship, it selects the reference point distribution method, calculates the reference unit, obtains the PRACH-related parameters, and then broadcasts them to the UE through the SSB and SIB1. The broadcast content includes information such as the mapping between the SSB and the PRACH occasion, the reference point configuration, and the beamfront latitude and longitude.

[0044] The UE obtains its current location, combines the latitude and longitude of the wave position in SIB1 with the reference point configuration, calculates its corresponding reference point, and selects the nearest target reference point. Based on the SSB-PRACH occasion mapping relationship, the current SSB and reference point position, it calculates the PRACH occasion and preamble to be selected, and sends Msg1 to the gNB via PRACH. Figure 8 As shown.

[0045] The gNB determines the reference point location selected by the UE based on the received PRACH occasion and preamble. Based on the beamwidth location information and the reference point location, it determines the UE's azimuth. After calculating the subsequent uplink and downlink beamforming angles for random access, it performs uplink and downlink beamforming transmission and reception based on these angles, involving Msg2 to Msg5 messages. Therefore, this application can achieve beamforming during the random access process, improving the access success rate. Figure 9 As shown, after the UE sends Msg1, the base station can obtain a more accurate position of the UE within the beam position. The beam direction of the Msg2-Msg5 link points to reference point 01, which is closer to the actual position of the UE, while the original beam direction points to the center of the beam position, which is too far away from the UE.

[0046] Corresponding to the embodiments of the base station-side method, this disclosure also provides embodiments of base station equipment for implementing beamforming-based random access in NTN.

[0047] Figure 12 This is a structural block diagram of the base station equipment provided in the embodiments of this disclosure.

[0048] like Figure 12 As shown, the base station equipment 300 includes a beamforming parameter acquisition module 310, a configuration management module 320, a system message processing module 330, a signal reception and determination module 340, and a beamforming control module 350. This base station equipment 300 can implement various methods executed on the base station side in the aforementioned embodiments. Each module can be implemented through software, hardware, or a combination of both.

[0049] The parameter acquisition module 310 is used to acquire the planning parameters of the wave position within the coverage area.

[0050] The configuration management module 320 is used to determine the reference point configuration within the wave position based on the preset reference point mapping rules.

[0051] The system message processing module 330 is used to generate and send system messages for different wave positions, which carry the position information of the current wave position and the reference point configuration.

[0052] The signal receiving and determining module 340 is used to receive the first signal sent by the user terminal during the random access process, and to determine the target reference point selected by the user terminal based on the random access resources used by the first signal. The first signal is generated by the user terminal after selecting the target reference point based on its own location, the position information of the wave position carried in the system message, and the reference point configuration, and then using the random access resources corresponding to the target reference point.

[0053] The beamforming control module 350 is used to perform beamforming based on the position of the target reference point and to complete random access with the user terminal.

[0054] Furthermore, the base station equipment in this embodiment of the present disclosure also has a local wavelength position database, from which the parameter acquisition module 310 obtains wavelength position planning parameters. Traditional base stations, however, do not store wavelength position data locally.

[0055] Corresponding to the method in the user terminal side embodiment, this disclosure also provides embodiments for implementing an NTN user terminal with beamforming-based random access in an NTN.

[0056] Figure 13 This is a structural block diagram of the user terminal provided in this embodiment.

[0057] like Figure 13 As shown, the user terminal 400 includes a positioning module 410, a system message parsing module 420, a reference point determination module 430, and a random access module 440. The user terminal 400 can implement various methods executed on the user terminal side in the aforementioned embodiments. Each module can be implemented through software, hardware, or a combination of both.

[0058] The positioning module 410 is used to determine the geographical location of the user terminal itself.

[0059] The system message parsing module 420 is used to receive and parse system messages sent by the base station for different wavelengths, and obtain the current wavelength location information and reference point configuration carried in them; the reference point configuration is determined by the base station according to the wavelength planning parameters in the coverage area and the preset reference point mapping rules.

[0060] The reference point determination module 430 is used to determine the target reference point based on its own geographical location, wave position information, and reference point configuration.

[0061] The random access module 440 is used to generate a first signal using the random access resources corresponding to the target reference point during the random access process and send it to the base station so that the base station can determine the target reference point based on the random access resources used by the first signal and perform beamforming based on the position of the target reference point to complete the random access process.

[0062] Figure 14This is a schematic diagram of the functional modules of a base station and a terminal provided in another embodiment.

[0063] like Figure 14 As shown, in this embodiment, the existing NTN base station and UE are modified to obtain base station 500 and UE600.

[0064] On the base station side, the existing scheduling module 510, beamforming module 520, and system broadcast module 530 remain unchanged; the original random access module 540 has been modified; and a beam position database 550 and an SIB1 recoding module 560 have been added. The functions of each module in this embodiment are as follows: The 550-band database stores the geographical location information of each band position. Based on this, the scheduling module can perform downlink beamforming calculation for SSB and SIB, uplink beamforming calculation for PRACH reception, and subsequent calculation of the geographical location corresponding to constellation points, thereby performing beamforming calculation for the remaining random access process.

[0065] The SIB1 recoding module 560 is used by the scheduling module to recode the latitude and longitude coordinates of different wave positions into SIB1 when the scheduling module performs SIB1 transmission, so as to notify the users of the corresponding wave positions to obtain the latitude and longitude of the wave position center.

[0066] The random access module 540 provides the scheduling module with the SSB and PRACH occasion mapping relationship so that PRACH configuration can be issued in SIB1. On the other hand, it is used to determine the reference point position based on the PRACH reported by the UE and feed it back to the scheduling module.

[0067] On the terminal side, the existing scheduling module 610, beamforming module 620, and positioning module 630 remain unchanged; however, the original random access module 640 and SIB1 parsing module 650 have been modified. The functions of each module in this embodiment are as follows: The SIB1 parsing module 650 is used to parse the newly defined SIB1, including parameters such as wave position latitude and longitude, and reference point configuration.

[0068] The random access module 640 needs to select the corresponding PRACH Hoccasion and preamble based on the real-time location provided by the positioning module 630 and the reference point and wave position latitude and longitude configuration provided by the SIB1 resolution module 650, combined with the SSB and PRACH occasion configuration, and initiate random access.

[0069] The modules described above in the various embodiments of this disclosure can be implemented in software, in programmable hardware, or in a combination of both. The described modules can also be located in a processor, and the names of these modules do not necessarily limit the module itself.

[0070] The various embodiments in this disclosure are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, for embodiments such as base station equipment and user terminals other than the method, since they are basically similar to the method embodiments, the description is relatively simple, and relevant parts can be referred to the description of the method embodiments. They also have similar beneficial technical effects to the corresponding method. Since the beneficial technical effects of the method have been described in detail above, they will not be repeated here.

[0071] The foregoing has described specific embodiments of this disclosure. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims may be performed in a different order than that shown in the embodiments and may still achieve the desired result. Furthermore, the processes depicted in the drawings do not necessarily require the specific or sequential order shown to achieve the desired result. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0072] In the 1990s, improvements to a technology could be clearly distinguished as either hardware improvements (e.g., improvements to the circuit structure of diodes, transistors, switches, etc.) or software improvements (improvements to the methodology). However, with technological advancements, many methodological improvements today can be considered direct improvements to the hardware circuit structure. Designers almost always obtain the corresponding hardware circuit structure by programming the improved methodology into the hardware circuit. Therefore, it cannot be said that a methodological improvement cannot be implemented using hardware physical modules. For example, a Programmable Logic Device (PLD) (such as a Field Programmable Gate Array (FPGA)) is such an integrated circuit whose logic function is determined by the user programming the device. Designers can program and "integrate" a digital system onto a PLD themselves, without needing chip manufacturers to design and manufacture dedicated integrated circuit chips. Furthermore, nowadays, instead of manually manufacturing integrated circuit chips, this programming is mostly implemented using "logic compiler" software. Similar to the software compiler used in program development, the original code before compilation must also be written in a specific programming language, called a Hardware Description Language (HDL). There are many HDLs, such as ABEL (Advanced Boolean Expression Language), AHDL (Altera Hardware Description Language), Confluence, CUPL (Cornell University Programming Language), HDCal, JHDL (Java Hardware Description Language), Lava, Lola, MyHDL, PALASM, and RHDL (Ruby Hardware Description Language). Currently, the most commonly used are VHDL (Very-High-Speed ​​Integrated Circuit Hardware Description Language) and Verilog. Those skilled in the art should also understand that by simply performing some logic programming on the method flow using one of these hardware description languages ​​and programming it into an integrated circuit, the hardware circuit implementing the logical method flow can be easily obtained.

[0073] The controller can be implemented in any suitable manner. For example, it can take the form of a microprocessor or processor and a computer-readable medium storing computer-readable program code (e.g., software or firmware) executable by the (micro)processor, logic gates, switches, application-specific integrated circuits (ASICs), programmable logic controllers, and embedded microcontrollers. Examples of controllers include, but are not limited to, the following microcontrollers: ARC 625D, Atmel AT91SAM, Microchip PIC18F26K20, and Silicon Labs C8051F320. A memory controller can also be implemented as part of the control logic of the memory. Those skilled in the art will also recognize that, in addition to implementing the controller in purely computer-readable program code form, the same functionality can be achieved by logically programming the method steps to make the controller take the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers. Therefore, such a controller can be considered a hardware component, and the means included therein for implementing various functions can also be considered as structures within the hardware component. Alternatively, the means for implementing various functions can be considered as both software modules implementing the method and structures within the hardware component.

[0074] The systems, devices, modules, or units described in the above embodiments can be implemented by computer chips or entities, or by products with certain functions. A typical implementation device is a computer. Specifically, a computer can be, for example, a personal computer, laptop computer, cellular phone, camera phone, smartphone, personal digital assistant, media player, navigation device, email device, game console, tablet computer, wearable device, or any combination of these devices.

[0075] For ease of description, the above apparatus is described by dividing it into various functional unit modules. Of course, when implementing one or more embodiments of this specification, the functions of each unit module can be implemented in one or more software and / or hardware.

[0076] Those skilled in the art will understand that the embodiments of this specification can be provided as methods, systems, devices, or computer program products. Therefore, the embodiments of this specification can take the form of entirely hardware embodiments, entirely software embodiments, or embodiments combining software and hardware aspects. Furthermore, the embodiments of this specification can take the form of computer program products implemented on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0077] This specification is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this specification. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data-optimized device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data-optimized device, produce a machine for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0078] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data optimization device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0079] These computer program instructions can also be loaded onto a computer or other programmable data optimization device to cause a series of operational steps to be performed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable device for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0080] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0081] Memory may include non-persistent storage in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0082] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0083] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0084] This specification can be described in the general context of computer-executable instructions that are executed by a computer, such as program modules. Generally, program modules include routines, programs, objects, components, data structures, etc., that perform a specific task or implement a specific abstract data type. This specification can also be practiced in distributed computing environments, where tasks are performed by remote processing devices connected via a communication network. In distributed computing environments, program modules can reside on local and remote computer storage media, including storage devices.

[0085] The above description is merely an embodiment of this disclosure and is not intended to limit the scope of this disclosure. Various modifications and variations can be made to this disclosure by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the scope of the claims of this disclosure.

Claims

1. A beamforming-based random access method in an NTN, executed by an NTN base station, characterized in that, The method includes: Obtain the wave position planning parameters within the coverage area; Based on the wave position planning parameters and the preset reference point mapping rules, the configuration of reference points within the wave position is determined; System messages are sent for different wavelengths, carrying the current wavelength's position information and the reference point configuration; The system receives a first signal sent by a user terminal during random access and determines a target reference point based on the random access resources used by the first signal. The first signal is generated by the user terminal after selecting a target reference point based on its own location, the position information of the wave position carried in the system message, and the reference point configuration, and then using the random access resources corresponding to the target reference point. Beamforming is performed based on the location of the target reference point to complete random access with the user terminal.

2. The method according to claim 1, characterized in that, The preset reference point mapping rules define the location distribution of multiple reference points within the wavelength range, as well as the correspondence between each reference point and a set of random access resources. In each reference point location distribution method, different reference points are configured with different random access resources.

3. The method according to claim 1, characterized in that, The reference point configuration includes a regular or irregular distribution of multiple reference points in a predetermined coordinate system, as well as the distance reference unit in the predetermined coordinate system.

4. The method according to claim 3, characterized in that, The distribution of multiple reference points can be any of the following: N reference points are evenly distributed in a grid pattern in a rectangular coordinate system, and the value of N must include at least 4 and 16. M reference points are evenly distributed radially in the polar coordinate system, where M is an integer greater than 1.

5. The method according to claim 3, characterized in that, The distance reference unit is set as the straight-line distance between the current wave position center point and the preset reference point or the projected distance in the preset direction.

6. The method according to claim 1, characterized in that, The system message is obtained by recoding based on SIB1 information.

7. The method according to claim 1, characterized in that, The beamforming based on the location of the target reference point includes: pointing the beam to the location of the target reference point, or the geographic center of the sub-region corresponding to the target reference point, or the weight center location calculated from historical access data in the sub-region corresponding to the target reference point.

8. A beamforming-based random access method in an NTN, executed by a user terminal, characterized in that, The method includes: Determine the geographical location of the user terminal itself; The system receives and parses system messages sent by the base station for different wavelengths, and obtains the current wavelength location information and reference point configuration carried therein; the reference point configuration is determined by the base station according to the wavelength planning parameters within the coverage area and the preset reference point mapping rules; The target reference point is determined based on its own geographical location, the position information of the wave position, and the configuration of the reference point. During the random access process, a first signal is generated using the random access resources corresponding to the target reference point and sent to the base station, so that the base station can determine the target reference point based on the random access resources used by the first signal, and perform beamforming based on the position of the target reference point to complete the random access process.

9. An NTN base station device, characterized in that, include: Wave position parameter acquisition module, used to acquire the planning parameters of wave position within the coverage area; The configuration management module is used to determine the reference point configuration within the wave position based on preset reference point mapping rules; The system message processing module is used to generate and send system messages for different wave positions, which carry the position information of the current wave position and the reference point configuration; The signal receiving and determining module is used to receive a first signal sent by the user terminal during random access, and to determine the target reference point selected by the user terminal based on the random access resources used by the first signal; the first signal is generated by the user terminal after selecting the target reference point based on its own location, the position information of the wave position carried in the system message and the reference point configuration, and then using the random access resources corresponding to the target reference point. The beamforming control module is used to perform beamforming based on the position of the target reference point and to complete random access with the user terminal.

10. An NTN user terminal, characterized in that, include: The positioning module is used to determine the geographical location of the user terminal itself; The system message parsing module is used to receive and parse system messages sent by the base station for different wavelengths, and obtain the current wavelength location information and reference point configuration carried therein; the reference point configuration is determined by the base station according to the wavelength planning parameters within the coverage area and the preset reference point mapping rules; The reference point determination module is used to determine the target reference point based on its own geographical location, the position information of the wave position, and the reference point configuration. The random access module is used to generate a first signal using the random access resources corresponding to the target reference point during the random access process and send it to the base station, so that the base station can determine the target reference point based on the random access resources used by the first signal and perform beamforming based on the position of the target reference point to complete the random access process.

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