Signal transmission methods and apparatuses, and storage medium and program product

Abstract

The present disclosure relates to the technical field of communications. Provided are signal transmission methods and apparatuses, and a storage medium and a program product, which are conducive to reducing the resource overhead of reference signals and improving the spectral efficiency. A signal transmission method comprises: determining frequency-domain resources for transmitting reference signals; dividing the frequency-domain resources into X frequency-domain resource groups, wherein each of the X frequency-domain resource groups comprises at least one resource block, the resource block comprising at least one resource element, and X being a positive integer; for at least one port among K ports of a first node, determining resource elements occupied by the at least one port in the X frequency-domain resource groups, K being a positive integer greater than or equal to 1; and sending the reference signals on the determined resource elements by means of the at least one port among the K ports.

Description

Signal transmission methods, devices, storage media and software products

[0001] This disclosure claims priority to Chinese patent application No. 202411219374.2, filed on August 30, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This disclosure relates to the field of communication technology, and in particular to a signal transmission method, apparatus, storage medium, and program product. Background Technology

[0003] In wireless communication systems, employing antenna arrays with integrated antenna elements is a key technology for improving base station performance. This design significantly enhances the base station's signal processing capabilities, primarily in two aspects: first, it improves signal transmission reliability through spatial diversity gain, reducing the impact of signal fading and interference; second, it utilizes beamforming technology to enhance and suppress signals in specific directions, thereby improving spectral efficiency and cell capacity. With the increase in the number of antennas, base stations can more precisely control signal transmission and reception, meeting the ever-growing demands of wireless communication.

[0004] However, while leveraging massive MIMO (Massively Large Array) antennas (MLAs) to improve performance, a significant challenge arises: the overhead of the reference signal. For example, to obtain accurate channel state information (CSI), the base station needs to send CSI reference signals to the user equipment. Under traditional reference signal transmission strategies, the overhead is directly proportional to the number of antenna ports, meaning that as the number of antennas increases, the transmission resources occupied by the reference signal also increase. For very large MIMO antenna arrays, this reference overhead can become enormous, consuming excessive transmission resources and impacting normal data transmission. This not only reduces the overall efficiency of the system but may also affect user experience and communication quality. Therefore, effectively reducing the overhead of the reference signal has become a crucial issue that needs to be addressed in the practical application of MLA technology. Summary of the Invention

[0005] This disclosure provides a signal transmission method, apparatus, storage medium, and program product, which helps to reduce reference signal resource overhead and improve spectral efficiency. The technical solutions provided by this disclosure are as follows:

[0006] On the one hand, a signal transmission method is provided, applied to a first node, the method comprising:

[0007] Determine the frequency domain resources to be used for transmitting the reference signal;

[0008] The frequency domain resources are divided into X frequency domain resource groups. Each of the X frequency domain resource groups contains at least one resource block. The resource block includes at least one resource element. X is a positive integer.

[0009] For at least one of the K ports of the first node, determine the resource element occupied by at least one port in the X frequency domain resource groups, where K is a positive integer greater than or equal to 1;

[0010] A reference signal is sent on a given resource element through at least one of the K ports.

[0011] On the other hand, a signal transmission method is provided for application to a second node, the method comprising:

[0012] The first node receives a reference signal transmitted on a resource element through at least one of the K ports. The resource element includes the resource element occupied by at least one of the K ports in X frequency domain resource groups. The X frequency domain resource groups are obtained by dividing the frequency domain resources used for transmitting the reference signal. Each of the X frequency domain resource groups contains at least one resource block, and the resource block contains at least one resource element. X is a positive integer, and K is a positive integer greater than or equal to 1.

[0013] On another front, a signal transmission device is provided for use at a first node, the device comprising:

[0014] A processing module is used to determine the frequency domain resources used for transmitting reference signals;

[0015] The processing module is also used to divide the frequency domain resources into X frequency domain resource groups, each of the X frequency domain resource groups contains at least one resource block, and the resource block includes at least one resource element, where X is a positive integer;

[0016] The processing module is also used to determine, for at least one of the K ports of the first node, the resource element occupied by at least one port in the X frequency domain resource groups, where K is a positive integer greater than or equal to 1;

[0017] A communication module for transmitting reference signals on a defined resource element via at least one of K ports.

[0018] On another front, a signal transmission device is provided for use in a second node, the device comprising:

[0019] The communication module is used to receive the reference signal transmitted by the first node on a resource element through at least one of the K ports. The resource element includes the resource element occupied by at least one of the K ports in X frequency domain resource groups. The X frequency domain resource groups are obtained by dividing the frequency domain resources used for transmitting the reference signal. Each of the X frequency domain resource groups contains at least one resource block, and the resource block includes at least one resource element. X is a positive integer, and K is a positive integer greater than or equal to 1.

[0020] In another aspect, a communication device is provided, comprising: a memory and a processor; the memory and the processor are coupled; the memory is used to store computer program instructions executable by the processor; and the processor implements the signal transmission method of any of the above embodiments when executing the computer program instructions.

[0021] In another aspect, a computer-readable storage medium is provided, on which computer program instructions are stored, which, when executed on a computer (e.g., a communication device or a signal transmission device), implement the signal transmission method of any of the above embodiments.

[0022] In another aspect, a computer program product is provided, which includes computer program instructions that, when executed, implement the signal transmission method of any of the above embodiments.

[0023] The technical solution provided in this disclosure acquires frequency domain resources for transmitting reference signals; divides the frequency domain resources into X frequency domain resource groups, each of which contains at least one resource block, and each resource block includes at least one resource element; for at least one port among the K ports of the first node, determines the resource element occupied by at least one port in the X frequency domain resource groups, and transmits the reference signal on the determined resource element through at least one port among the K ports. In this way, by determining the resource elements occupied by different ports in the X frequency domain resource groups, the significant increase in transmission resources occupied by the reference signal as the number of ports increases is avoided, allowing for differences in the number of REs occupied by different ports in the frequency domain dimension, thereby reducing reference signal resource overhead and improving spectral efficiency. Simultaneously, by utilizing the correlation between different ports, the receiving end can still accurately recover channel state information, ensuring communication quality. Attached Figure Description

[0024] Figure 1 is a schematic diagram of the architecture of a communication system provided in an embodiment of this disclosure;

[0025] Figure 2 is a flowchart of a signal transmission method provided in an embodiment of this disclosure;

[0026] Figure 3 is a schematic diagram of frequency domain resource group partitioning provided in an embodiment of this disclosure;

[0027] Figure 4 is a schematic diagram of another frequency domain resource group partitioning provided in an embodiment of this disclosure;

[0028] Figure 5 is a schematic diagram of another frequency domain resource group partitioning provided in an embodiment of this disclosure;

[0029] Figure 6 is a schematic diagram of a time-frequency resource provided in an embodiment of this disclosure;

[0030] Figure 7 is a schematic diagram of another time-frequency resource provided in an embodiment of this disclosure;

[0031] Figure 8 is a schematic diagram of yet another time-frequency resource provided in an embodiment of this disclosure;

[0032] Figure 9 is a flowchart of another signal transmission method provided in an embodiment of this disclosure;

[0033] Figure 10 is a schematic diagram of a signal transmission device provided in an embodiment of this disclosure;

[0034] Figure 11 is a schematic diagram of another signal transmission device provided in an embodiment of this disclosure;

[0035] Figure 12 is a schematic diagram of the structure of a communication device provided in an embodiment of this disclosure. Detailed Implementation

[0036] The technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments of this disclosure, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this disclosure.

[0037] In this disclosure, unless otherwise stated, " / " means "or," for example, A / B can mean A or B. "And / or" in this document is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, and B alone. Furthermore, "at least one" means one or more, and "multiple" means two or more. The terms "first," "second," etc., do not limit the quantity or order of execution, and "first," "second," etc., do not necessarily imply differences.

[0038] It should be noted that in this disclosure, the words "exemplarily" or "for example" are used to indicate examples, illustrations, or explanations. Any embodiment or design described as "exemplarily" or "for example" in this disclosure should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of words such as "exemplarily" or "for example" is intended to present the relevant concepts by way of example.

[0039] Massive multiple-input multiple-output (MIMO) is a key technology in 5G mobile communication systems. Its core feature is that the base station (BS) is equipped with a large number of antenna elements, using spatial multiplexing technology to improve cell capacity. To ensure performance, the BS needs to transmit pilot signals, namely channel state information-reference signals (CSI-RS), to the user equipment (UE). After completing pilot measurements, the UE feeds back the channel state information to the BS for reference.

[0040] In relevant technical standards, the number of CSI-RS ports is proportional to the number of antenna array elements, and they are transmitted periodically in the time and frequency domains. For example, one CSI-RS resource can contain a maximum of 32 CSI-RS ports, and the current R19 standard version is discussing extending this number to 128. The density of CSI-RS used for channel measurements in the frequency domain is 1 or 0.5 RE / port / resource block (RB), meaning that for each CSI-RS port, it occupies one resource element (RE) in every one or two RBs. Furthermore, all CSI-RS ports occupy the same number of REs within an RB.

[0041] To further improve communication performance, future mobile communication systems will employ larger-scale antenna arrays, integrating more antenna elements, leading to a dramatic increase in the number of CSI-RS ports. Under the current CSI-RS transmission strategy, assuming 1024 CSI-RS ports, a frequency domain density of 0.5 RE / port / RB, and a time domain period of 10 slots, CSI-RS alone accounts for over 30% of transmission resources, while the traditional 32-port pilot overhead accounts for only 3%. Therefore, excessive pilot overhead consumes too many transmission resources, severely limiting the improvement of spectral efficiency.

[0042] In view of this, this disclosure provides a signal transmission method by acquiring frequency domain resources for transmitting reference signals; dividing the frequency domain resources into X frequency domain resource groups, each of the X frequency domain resource groups containing at least one resource block, and each resource block including at least one resource element; for at least one port among the K ports of a first node, determining the resource element occupied by at least one port in the X frequency domain resource groups, and transmitting the reference signal on the determined resource element through at least one port among the K ports. In this way, compared to related technologies where the number of resource elements occupied by reference signals transmitted from different ports is the same in the frequency domain, determining the resource elements occupied by different ports in the X frequency domain resource groups avoids a significant increase in transmission resources occupied by the reference signal as the number of ports increases, allowing for differences in the number of REs occupied by different ports in the frequency domain dimension, thereby reducing reference signal resource overhead and improving spectral efficiency. Simultaneously, by utilizing the correlation between different ports, the receiving end can still accurately recover channel state information, ensuring communication quality.

[0043] The signal transmission method provided in this disclosure can be applied to systems with various communication standards. For example, the systems to which the signal transmission method provided in this disclosure is applicable include, but are not limited to, long-term evolution (LTE) systems, various versions of LTE-based systems, 5G systems, and ambient internet of things (Ambient IoT) communication systems. Furthermore, the signal transmission method provided in this disclosure can also be applied to future-oriented communication systems (such as 6G communication systems).

[0044] In this embodiment of the disclosure, the network architecture of the mobile communication network (including but not limited to 3G, 4G, 5G, and future mobile communication networks) may include at least a first communication node and a second communication node. It should be understood that, in this example, in the downlink, the first communication node may be a network-side device (e.g., including but not limited to a base station), and the second communication node may be a terminal-side device (e.g., including but not limited to a terminal).

[0045] Of course, in the uplink, the first communication node can be a terminal-side device, and the second communication node can be a network-side device. In device-to-device communication between the two communication nodes, both the first and second communication nodes can be base stations or terminals. The first and second communication nodes can be simply referred to as the first node and the second node, respectively.

[0046] For example, taking a first communication node as a base station and a second communication node as a terminal, as shown in Figure 1, a communication system provided in this embodiment of the disclosure includes a terminal 10 and a base station 20. There can be one or more terminals 10 and base stations 20, and the number is not limited.

[0047] In some embodiments, base station 20 provides wireless access service to terminal 10. A base station 20 provides at least one service coverage area (also referred to as a cell). Terminal 10 entering this area can communicate with base station 20 via wireless signals to receive the wireless access service provided by base station 20.

[0048] In some embodiments, the base station may be a base station in LTE, long term evolution advanced (LTEA) or an evolved Node B (eNB or eNodeB), a base station device in a 5G network, or a base station in a future communication system, etc. The base station may include various macro base stations, micro base stations, home base stations, wireless remotes, reconfigurable intelligent surfaces (RISs), routers, relays, multiple transmission reception points (TRPs), wireless fidelity (WIFI) devices, UEs and other network-side devices.

[0049] In some embodiments, the terminal can be a device with wireless transceiver capabilities. The terminal can be a passive device, an ambient IoT device, a mobile phone, a tablet computer, a computer with wireless transceiver capabilities, a virtual reality (VR) terminal, an augmented reality (AR) terminal, a wireless terminal in industrial control, a wireless terminal in self-driving, a wireless terminal in remote medical care, a wireless terminal in a smart grid, a wireless terminal in transportation safety, a wireless terminal in a smart city, a wireless terminal in a smart home, etc. The embodiments of this disclosure do not limit the application scenarios. The terminal may also be referred to as a user, UE, access terminal, UE unit, UE station, mobile station, mobile station, remote station, remote terminal, mobile device, UE terminal, wireless communication device, UE agent, or UE device, etc., and the embodiments of this disclosure do not limit this to these terms.

[0050] It should be noted that Figure 1 is only an exemplary framework diagram. The number of devices included in Figure 1 and the names of each device are not limited. In addition to the devices shown in Figure 1, the communication system may also include other devices, such as core network devices.

[0051] The embodiments disclosed herein do not limit the application scenarios. The system architecture and business scenarios described in the embodiments of this disclosure are for the purpose of more clearly illustrating the technical solutions of the embodiments of this disclosure, and do not constitute a limitation on the technical solutions provided by the embodiments of this disclosure. As those skilled in the art will know, with the evolution of network architecture and the emergence of new business scenarios, the technical solutions provided by the embodiments of this disclosure are also applicable to similar technical problems.

[0052] This disclosure provides a signal transmission method applied to a first node. As shown in Figure 2, the method includes the following steps:

[0053] S101. Determine the frequency domain resources used for transmitting the reference signal.

[0054] Here, the frequency domain resources used for transmitting the reference signal can be the entire bandwidth parts (BWP) or a portion of the BWP. The frequency domain resources used for transmitting the reference signal can also be referred to as the frequency domain resource range used for transmitting the reference signal; this disclosure does not impose any limitation on this.

[0055] In some embodiments, the reference signal may be a pilot signal or other types of reference signals, such as CSI-RS.

[0056] S102. Divide the frequency domain resources into X frequency domain resource groups.

[0057] Here, each of the X frequency domain resource groups contains at least one resource block, and each resource block includes at least one resource element, where X is a positive integer. Frequency domain resource groups may also have other names, such as RB subgroups, etc., and this disclosure does not impose any restrictions on this.

[0058] In some embodiments, at least two of the X frequency domain resource groups contain the same number of resource blocks.

[0059] In some embodiments, when the value of X cannot be divided evenly by the number of RBs included in the frequency domain resource, the number of RBs included in the frequency domain resource group located at the edge position (or at both ends of the frequency domain resource) may be different from the number of RBs included in other frequency domain resource groups.

[0060] For example, as shown in Figure 3, assume that the frequency domain resources used to transmit the reference signal include 10 RBs. The first node determines that the vast majority of frequency domain resource groups contain 4 RBs. Since 4 is not divisible by 10, some frequency domain resource groups have different sizes than others. The partitioning method in Figure 3(a) is characterized by dividing the frequency domain resource groups starting from the beginning of the RBs, with every 4 RBs forming one frequency domain resource group, and the remaining 2 RBs automatically assigned to the last frequency domain resource group 3. The partitioning method in Figure 3(b) is characterized by ensuring that the smaller frequency domain resource groups are distributed at both ends, that is, frequency domain resource group 1 and frequency domain resource group 4 each contain 1 RB, and other frequency domain resource groups contain 4 RBs.

[0061] In some embodiments, the frequency domain resources are divided into X frequency domain resource groups according to at least one of the following:

[0062] The possible values ​​of K;

[0063] The prior agreement between the first and second nodes;

[0064] Signaling configuration of the first node; or

[0065] Signaling configuration for the second node.

[0066] In some embodiments, when a frequency domain resource group contains at least two resource blocks, the different resource blocks within the frequency domain resource group may be continuous or discontinuous in the frequency domain.

[0067] In some embodiments, when different resource blocks within a frequency domain resource group are not contiguous in the frequency domain, the number of resource blocks that separate adjacent resource blocks within the frequency domain resource group is the same.

[0068] For example, as shown in Figure 4, a frequency domain resource group partitioning method is illustrated, characterized by the same number of resource blocks separating adjacent resource blocks within a frequency domain resource group. For instance, in Figure 4(a), RBs separated by 1 RB (or RBs with a difference of 2 in RB number) belong to the same frequency domain resource group, and in Figure 4(b), RBs separated by 2 RBs (or RBs with a difference of 3 in RB number) belong to the same frequency domain resource group. Here, the reference signal transmission strategy can be the same for each RB within the same RB subgroup, as described in the examples or embodiments below.

[0069] In some embodiments, the value of X is determined based on at least one of the following:

[0070] The possible values ​​of K;

[0071] The prior agreement between the first and second nodes;

[0072] Signaling configuration of the first node; or

[0073] Signaling configuration for the second node.

[0074] In some embodiments, the number of resource elements contained in at least one of the X frequency domain resource groups is determined according to at least one of the following:

[0075] The possible values ​​of K;

[0076] The prior agreement between the first and second nodes;

[0077] Signaling configuration of the first node; or

[0078] Signaling configuration for the second node.

[0079] For example, taking the first node as the BS, the second node as the UE, and the reference signal as CSI-RS, the UE confirms the variation characteristics of the channel matrix in the spatial and frequency domains based on the measurement results of CSI-RS, and accordingly sends signaling configuration to the BS. This signaling configuration includes, but is not limited to, information such as the method of dividing the frequency domain resources used for transmitting the reference signal into X frequency domain resource groups, the value of X, and the number of RBs contained in each frequency domain resource group. Here, the information such as the method of dividing the frequency domain resources used for transmitting the reference signal into X frequency domain resource groups, the value of X, and the number of RBs contained in each frequency domain resource group can also be included in the reference signal transmission strategy and sent to the BS through signaling configuration.

[0080] For example, as shown in Figure 5, a pilot transmission strategy is illustrated when the number of ports in the CSI-RS resource varies. Specifically, the frequency domain resources for transmitting CSI-RS are divided into X frequency domain resource groups based on the number of ports (the value of K). Assume that each RB occupies 4 REs for CSI-RS, meaning each RB can contain 4 ports, and these 4 ports can transmit CSI-RS using the CDM method.

[0081] In Figure 5(a), when the number of ports included in the CSI-RS resource is 16, all RBs that transmit CSI-RS are divided into 4 frequency domain resource groups. RBs with a gap of 3 RBs (that is, RB numbers that differ by 4) belong to one frequency domain resource group (for example, RB n and RB n+4 belong to the same frequency domain resource group). A specific port occupies REs only in one frequency domain resource group and occupies 0 REs in other frequency domain resource groups. For example, ports 1 / 5 / 9 / 13 only occupy REs in the frequency domain resource group where RB n is located and occupy 0 REs in other frequency domain resource groups.

[0082] In Figure 5(b), when the number of ports included in the CSI-RS resource is 8, all RBs that transmit CSI-RS are divided into 2 frequency domain resource groups. RBs that are 1 RB apart (that is, RB numbers that differ by 2) belong to the same frequency domain resource group (for example, RB n and RB n+2 belong to the same frequency domain resource group). A specific port occupies REs only in one frequency domain resource group and occupies 0 REs in other frequency domain resource groups. For example, ports 1 / 3 / 5 / 7 only occupy REs in the frequency domain resource group to which RB n belongs and occupy 0 REs in another frequency domain resource group.

[0083] In Figure 5(c), when the CSI-RS resource contains 4 ports, all RBs can be regarded as a frequency domain resource group, and ports 1-4 occupy REs on each RB.

[0084] This introduces the concept of frequency domain resource groups, allowing us to determine the resources occupied by signals transmitted at different ports within each resource group, making signal transmission more flexible.

[0085] S103. For at least one of the K ports of the first node, determine the resource element occupied by at least one port in the X frequency domain resource groups.

[0086] Here, K is a positive integer greater than or equal to 1.

[0087] In some embodiments, the number of resource elements available for port occupancy is the same in each of the X frequency domain resource groups.

[0088] In some embodiments, at least one of the K ports occupies a different number of resource elements in at least two different frequency domain resource groups among the X frequency domain resource groups. In this way, compared to related technologies where all ports occupy the same number of REs in the RB, the present disclosure reduces pilot overhead by allowing ports to occupy different REs in different frequency domain resource groups. Utilizing the correlation between ports, the UE can use algorithms such as compressed sensing to obtain sufficiently accurate channel state information.

[0089] In some embodiments, when K is greater than 1, at least two of the K ports occupy different numbers of resource elements within the same one or more frequency domain resource groups.

[0090] In some embodiments, when K is greater than 1, at least two of the K ports occupy different numbers of resource elements in the same one or more frequency domain resource groups, and one of the at least two ports occupies 0 resource elements in the same one or more frequency domain resource groups, and the other ports besides the aforementioned one occupy more than 0 resource elements in the same one or more frequency domain resource groups.

[0091] In some embodiments, when K is greater than 1, at least two of the K ports occupy different or the same number of resource elements within the K frequency domain resource groups.

[0092] In some embodiments, when K is greater than 1, the number of resource elements occupied by different ports is different in each frequency domain resource group within the X frequency domain resource groups.

[0093] In some embodiments, the location and / or number of resource elements occupied by at least one port are determined according to at least one of the following methods:

[0094] The prior agreement between the first and second nodes;

[0095] Signaling configuration of the first node; or

[0096] Signaling configuration for the second node.

[0097] For example, taking the first node as the BS, the second node as the UE, and the reference signal as CSI-RS, if the UE measures and finds that the angle of arrival is within a certain range, it can recommend the BS to reduce the number of CSI-RS ports based on feedback information. In certain frequency domain resource groups, only the CSI-RS corresponding to a portion of the ports can be transmitted. The following embodiment illustrates this. The BS determines the number of ports in the CSI-RS resource and further determines the CSI-RS transmission strategy within each frequency domain resource group, including: the location and / or number of REs occupied by each port in each frequency domain resource group, and whether each port uses CDM mode to transmit CSI-RS, etc. This CSI-RS transmission strategy is agreed upon by the BS and the UE, or configured according to the transmission signaling. Finally, the BS transmits CSI-RS according to the stated CSI-RS transmission strategy.

[0098] In some embodiments, when K is greater than 1, the K ports are divided into at least two groups of ports, each group of ports including at least one port, and the at least two groups of ports satisfy at least one of the following:

[0099] There exists at least one set of ports where the number of resource elements occupied in a portion of the frequency domain resource groups is 0, and the number of resource elements occupied in other frequency domain resource groups other than the portion of the frequency domain resource groups is greater than 0.

[0100] There exists at least one group of ports in which the number of resource elements occupied in a portion of the frequency domain resource groups is greater than 0, and the number of resource elements occupied by other ports besides the at least one group of ports in the portion of the frequency domain resource groups is 0.

[0101] Different ports within the same port group occupy the same number of resource elements within the same frequency domain resource group; or

[0102] There exists at least one set of ports in which the resource elements occupy different positions in at least two different resource blocks within the same frequency domain resource group.

[0103] It is understandable that the resource elements occupied by the same port in at least two different resource blocks within the same frequency domain resource group are in different positions, which can be regarded as non-uniform sampling of the channel. Compared with the uniform sampling of related standards, it can recover channel state information with less reference signal resource overhead.

[0104] In some embodiments, when K is greater than 1, at least two of the K ports transmit the reference signals using code domain multiplexing (CDM).

[0105] In some embodiments, among the K ports, the port that transmits the reference signal using code field multiplexing is determined according to at least one of the following:

[0106] The prior agreement between the first and second nodes;

[0107] Signaling configuration of the first node; or

[0108] Signaling configuration for the second node.

[0109] For example, as shown in Figure 6, assuming the CSI-RS resource includes 12 ports, the frequency domain resources for transmitting CSI-RS (including RBs 1-10) are divided into three frequency domain resource groups: frequency domain resource group 1 (including RBs 1-4), frequency domain resource group 2 (including RBs 5-8), and frequency domain resource group 3 (including RBs 9-10). The CSI-RS transmission strategy within frequency domain resource group 2 is given (at least including the position and number of resource elements occupied by each port in different RBs).

[0110] The CSI-RS transmission strategy for other frequency domain resource groups can be the same as that for frequency domain resource group 2, or it can be different. When the CSI-RS transmission strategy is the same within each frequency domain resource group, for the smaller frequency domain resource group 3, its CSI-RS pattern (the CSI-RS pattern is used to represent the position and number of resource elements occupied by each port in the RB) can be specified to be periodic with other frequency domain resource groups, that is, the CSI-RS pattern of RB 9-10 is the same as that of RB 5-6 and RB 1-2.

[0111] In frequency domain resource group 2, the number of REs occupied by different ports varies. For example, ports 1-4 and 5-8 use CDM to transmit CSI-RS, each occupying 16 REs in frequency domain resource group 2, while ports 9-12 use CDM to transmit CSI-RS, each occupying 8 REs in frequency domain resource group 2. For different RBs in a frequency domain resource group, there are at least one set of ports occupying resource elements in different positions. For example, ports 1-4 occupy resource elements in the same position in the four RBs of frequency domain resource group 2, while ports 5-8 occupy resource elements in completely different positions in the four RBs of frequency domain resource group 2.

[0112] Another example, as shown in Figure 7, assumes that the CSI-RS resource contains 8 ports, and each frequency domain resource group contains 2 RBs. As a frequency domain resource group partitioning method, RB n and RB n+1 belong to the same frequency domain resource group, and RB n+2 and RB n+3 belong to the same frequency domain resource group. The CSI-RS transmission strategy can be the same within different frequency domain resource groups. Consider that in RB n and RB n+2, ports 1 and 2 use CDM multiplexing for transmission, ports 3 and 4 use CDM multiplexing for transmission, ports 5 and 6 use CDM multiplexing for transmission, and ports 7 and 8 use CDM multiplexing for transmission. Ports 1 / 3 / 5 / 7 occupy 3 REs within a frequency domain resource group, while ports 2 / 4 / 6 / 8 occupy 2 REs within the same group. For example, ports 1 / 3 / 5 / 7 occupy 2 REs in RB n+2 and 1 RE in RB n+3, while ports 2 / 4 / 6 / 8 occupy 2 REs in RB n+2 and 0 REs in RB n+3. Under this pilot transmission strategy, some resource blocks (e.g., RB n+1 and RB n+3) do not need to transmit the CSI-RS corresponding to all 8 ports; only the CSI-RS corresponding to some ports needs to be transmitted, thereby reducing pilot overhead.

[0113] As another method of partitioning frequency domain resource groups, RB n and RB n+2 belong to frequency domain resource group 1, while RB n+1 and RB n+3 belong to frequency domain resource group 2. Ports 1 / 3 / 5 / 7 occupy RE resources in both frequency domain resource group 1 and frequency domain resource group 2, while ports 2 / 4 / 6 / 8 occupy RE resources only in frequency domain resource group 1.

[0114] Another example, as shown in Figure 8, assumes that the CSI-RS resource contains 8 ports. As a frequency domain resource grouping method, each frequency domain resource group includes only 1 RB. The BS divides the 8 ports into two groups: port 1, port 3, port 5, and port 7 form one group, and port 2, port 4, port 6, and port 8 form another group. Ports 1 / 3 / 5 / 7 occupy 1 RE in RB n and RB n+2, but not in RB n+1 and RB n+3. Ports 2 / 4 / 6 / 8 occupy 1 RE in RB n+1 and RB n+3, but not in RB n and RB n+2. This pilot transmission strategy can save half of the pilot overhead. As another frequency domain resource grouping method, frequency domain resource group 1 includes RB n, RB n+2, etc., and frequency domain resource group 2 includes RB n+1, RB n+3, etc. Here, ports 1 / 3 / 5 / 7 only occupy REs in frequency domain resource group 1 and not in frequency domain resource group 2. Ports 2 / 4 / 6 / 8 occupy REs only in frequency domain resource group 1 and do not occupy REs in frequency domain resource group 2.

[0115] In addition to the port partitioning strategy described above, the BS can also use different partitioning methods when grouping ports. For example, ports 1-4 can be grouped together, and ports 5-8 can be grouped together. The association method between different port groups and frequency domain resource groups can be referred to the above embodiments or examples, and will not be repeated here.

[0116] S104. Send a reference signal on a determined resource element through at least one of the K ports.

[0117] In some embodiments, the first node periodically sends a reference signal to the second node on a determined resource element through at least one of the K ports.

[0118] Based on this, compared to related technologies where the reference signals transmitted from different ports occupy the same number of resource elements in the frequency domain, this approach determines the resource elements occupied by different ports in X frequency domain resource groups. This avoids a significant increase in transmission resources occupied by the reference signals as the number of ports increases, allowing for differences in the number of REs occupied by different ports in the frequency domain dimension. This reduces reference signal resource overhead and improves spectral efficiency. Simultaneously, by utilizing the correlation between different ports, the receiver can still accurately recover channel state information, ensuring communication quality.

[0119] This disclosure provides a signal transmission method applied to a second node. As shown in Figure 9, the method includes the following steps:

[0120] S201. Receive the reference signal sent by the first node on a determined resource element through at least one of the K ports.

[0121] Here, the resource element includes the resource element occupied by at least one of the K ports in the X frequency domain resource groups. The X frequency domain resource groups are obtained by dividing the frequency domain resources used for transmitting reference signals. Each of the X frequency domain resource groups contains at least one resource block, and the resource block contains at least one resource element. X is a positive integer, and K is a positive integer greater than or equal to 1.

[0122] In some embodiments, at least one of the K ports occupies a different number of resource elements in at least two different frequency domain resource groups among the X frequency domain resource groups.

[0123] In some embodiments, at least two of the K ports occupy different numbers of resource elements within the same one or more frequency domain resource groups.

[0124] In some embodiments, at least two of the K ports occupy different numbers of resource elements in the same one or more frequency domain resource groups, and one of the at least two ports occupies 0 resource elements in the same one or more frequency domain resource groups.

[0125] In some embodiments, the position or number of resource elements occupied by at least one of the K ports in the X frequency domain resource groups is determined according to at least one of the following methods:

[0126] The prior agreement between the first and second nodes;

[0127] Signaling configuration of the first node; or

[0128] Signaling configuration for the second node.

[0129] In some embodiments, the number of resource elements available for port occupancy is the same within each frequency domain resource group.

[0130] In some embodiments, when K is greater than 1, at least two of the K ports transmit the reference signals using code domain multiplexing.

[0131] In some embodiments, when a frequency domain resource group contains at least two resource blocks, the different resource blocks within the frequency domain resource group may be continuous or discontinuous in the frequency domain.

[0132] In some embodiments, when different resource blocks within a frequency domain resource group are not contiguous in the frequency domain, the number of resource blocks that separate adjacent resource blocks within the frequency domain resource group is the same.

[0133] In some embodiments, the value of X is determined based on at least one of the following:

[0134] The possible values ​​of K;

[0135] The prior agreement between the first and second nodes;

[0136] Signaling configuration of the first node; or

[0137] Signaling configuration for the second node.

[0138] In some embodiments, the number of resource elements contained in at least one of the X frequency domain resource groups is determined according to at least one of the following:

[0139] The possible values ​​of K;

[0140] The prior agreement between the first and second nodes;

[0141] Signaling configuration of the first node; or

[0142] Signaling configuration for the second node.

[0143] Other relevant descriptions in this embodiment can be found in the descriptions in the relevant embodiments or examples on the first node side above, and will not be repeated here.

[0144] The foregoing primarily describes the solutions of the embodiments of this disclosure from a methodological perspective. The following also illustrates a signal transmission apparatus for executing the signal transmission methods in any of the above embodiments and their possible implementations. It is understood that, in order to implement the signal transmission method, the signal transmission apparatus includes hardware structures and / or software modules corresponding to the execution of various functions; those skilled in the art should readily recognize that, in conjunction with the algorithm steps of the various examples described in the embodiments of this disclosure, this disclosure can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed in hardware or by computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this disclosure.

[0145] This disclosure embodiment can divide the signal transmission device into functional modules according to the above method embodiment. For example, each function can be divided into a separate functional module, or two or more functions can be integrated into one functional module. The integrated module can be implemented in hardware or software. It should be noted that the module division in this disclosure embodiment is illustrative and only represents one logical functional division. In actual implementation, there may be other division methods. The following description uses the example of dividing each functional module according to each function.

[0146] Figure 10 illustrates a signal transmission device provided in an embodiment of this disclosure, applied to a first node. The signal transmission device 300 includes a processing module 301 and a communication module 302.

[0147] Processing module 301 is used to determine the frequency domain resources used for transmitting the reference signal;

[0148] Processing module 301 is further configured to divide the frequency domain resources into X frequency domain resource groups, each of the X frequency domain resource groups containing at least one resource block, the resource block including at least one resource element, and X being a positive integer;

[0149] The processing module 301 is also used to determine, for at least one of the K ports of the first node, the resource element occupied by at least one port in the X frequency domain resource groups, where K is a positive integer greater than or equal to 1;

[0150] Communication module 302 is used to send reference signals on a determined resource element through at least one of K ports.

[0151] In some embodiments, when K is greater than 1, at least two of the K ports occupy different numbers of resource elements within the same one or more frequency domain resource groups.

[0152] In some embodiments, at least one of the two ports occupies zero resource elements within the same one or more frequency domain resource groups.

[0153] In some embodiments, at least one of the K ports occupies a different number of resource elements in at least two different frequency domain resource groups among the X frequency domain resource groups.

[0154] In some embodiments, the location and / or number of resource elements occupied by at least one port are determined according to at least one of the following methods:

[0155] The prior agreement between the first and second nodes;

[0156] Signaling configuration of the first node; or

[0157] Signaling configuration for the second node.

[0158] In some embodiments, when K is greater than 1, at least two of the K ports transmit the reference signals using code domain multiplexing.

[0159] In some embodiments, the processing module 301 is further configured to divide the K ports into at least two groups of ports when K is greater than 1, each group of ports including at least one port, and the at least two groups of ports satisfy at least one of the following:

[0160] There exists at least one set of ports where the number of resource elements occupied in a portion of the frequency domain resource groups is 0, and the number of resource elements occupied in other frequency domain resource groups other than the portion of the frequency domain resource groups is greater than 0.

[0161] There exists at least one group of ports that occupy more than 0 resource elements in a portion of the frequency domain resource groups among X frequency domain resource groups, while other ports besides the at least one group occupy 0 resource elements in a portion of the frequency domain resource groups.

[0162] Different ports within the same group of ports occupy the same number of resource elements within the same frequency domain resource group;

[0163] There exists at least one group of ports occupying resource elements in at least two different resource blocks within the same frequency domain resource group, with the resource elements located at different positions.

[0164] In some embodiments, the number of resource elements available for port occupancy is the same within each frequency domain resource group.

[0165] In some embodiments, the frequency domain resources are divided into X frequency domain resource groups according to at least one of the following:

[0166] The possible values ​​of K;

[0167] The prior agreement between the first and second nodes;

[0168] Signaling configuration of the first node; or

[0169] Signaling configuration for the second node.

[0170] In some embodiments, when a frequency domain resource group contains at least two resource blocks, the different resource blocks within the frequency domain resource group may be continuous or discontinuous in the frequency domain.

[0171] In some embodiments, when different resource blocks within a frequency domain resource group are not contiguous in the frequency domain, the number of resource blocks that separate adjacent resource blocks within the frequency domain resource group is the same.

[0172] In some embodiments, the value of X is determined based on at least one of the following:

[0173] The possible values ​​of K;

[0174] The prior agreement between the first and second nodes;

[0175] Signaling configuration of the first node; or

[0176] Signaling configuration for the second node.

[0177] In some embodiments, the number of resource elements contained in at least one of the X frequency domain resource groups is determined according to at least one of the following:

[0178] The possible values ​​of K;

[0179] The prior agreement between the first and second nodes;

[0180] Signaling configuration of the first node; or

[0181] Signaling configuration for the second node.

[0182] For a more detailed description of the processing module 301 and the communication module 302, as well as a more detailed description of their respective technical features and beneficial effects, please refer to the corresponding method embodiment section above, which will not be repeated here.

[0183] Figure 11 illustrates another signal transmission device provided in an embodiment of this disclosure, applied to a second node. The signal transmission device 400 includes a communication module 401.

[0184] In some embodiments, the communication module 401 is configured to receive a reference signal transmitted by the first node on a determined resource element through at least one of K ports. The resource element includes the resource element occupied by at least one of the K ports in X frequency domain resource groups. The X frequency domain resource groups are obtained by dividing the frequency domain resources used for transmitting the reference signal. Each of the X frequency domain resource groups contains at least one resource block, and the resource block includes at least one resource element. X is a positive integer, and K is a positive integer greater than or equal to 1.

[0185] In some embodiments, at least one of the K ports occupies a different number of resource elements in at least two different frequency domain resource groups among the X frequency domain resource groups.

[0186] In some embodiments, at least two of the K ports occupy different numbers of resource elements within the same one or more frequency domain resource groups.

[0187] In some embodiments, one of the at least two ports occupies zero resource elements within the same one or more frequency domain resource groups.

[0188] In some embodiments, the position and / or number of resource elements occupied by at least one of the K ports in the X frequency domain resource groups are determined according to at least one of the following methods:

[0189] The prior agreement between the first and second nodes;

[0190] Signaling configuration of the first node; or

[0191] Signaling configuration for the second node.

[0192] In some embodiments, the number of resource elements available for port occupancy is the same within each frequency domain resource group.

[0193] In some embodiments, when a frequency domain resource group contains at least two resource blocks, the different resource blocks within the frequency domain resource group may be continuous or discontinuous in the frequency domain.

[0194] In some embodiments, when different resource blocks within a frequency domain resource group are not contiguous in the frequency domain, the number of resource blocks spaced between adjacent resource blocks within the frequency domain resource group is the same.

[0195] In some embodiments, the value of X is determined based on at least one of the following:

[0196] The possible values ​​of K;

[0197] The prior agreement between the first and second nodes;

[0198] Signaling configuration of the first node; or

[0199] Signaling configuration for the second node.

[0200] In some embodiments, the number of resource elements contained in at least one of the X frequency domain resource groups is determined according to at least one of the following:

[0201] The possible values ​​of K;

[0202] The prior agreement between the first and second nodes;

[0203] Signaling configuration of the first node; or

[0204] Signaling configuration for the second node.

[0205] For a more detailed description of the communication module 401, its various technical features, and its beneficial effects, please refer to the corresponding method embodiment section above, which will not be repeated here.

[0206] It should be noted that the modules in Figures 10 and 11 can also be called units; for example, a communication module can be called a communication unit. Furthermore, in the embodiments shown in Figures 10 and 11, the names of the modules may not be those shown in the figures; for example, a communication module can also be called a transmitting module or a receiving module.

[0207] If the various units or modules in Figures 10 and 11 are implemented as software functional modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solutions of the embodiments of this disclosure, in essence, or the parts that contribute to related technologies, or all or part of the technical solutions, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) or processor to execute all or part of the steps of the methods of the various embodiments of this disclosure. Storage media for storing computer software products include various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0208] In implementing the functions of the integrated modules described above in hardware, this disclosure also provides a possible structure for a communication device used to execute the signal transmission method provided in this disclosure. As shown in FIG12, the communication device 500 includes: a communication interface 503, a processor 502, and a bus 504. Optionally, the communication device may further include a memory 501.

[0209] Processor 502 may implement or execute various exemplary logic blocks, modules, and circuits described in conjunction with embodiments of this disclosure. Processor 502 may be a central processing unit, a general-purpose processor, a digital signal processor, an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. It may implement or execute various exemplary logic blocks, modules, and circuits described in conjunction with embodiments of this disclosure. Processor 502 may also be a combination that implements computational functions, such as a combination of one or more microprocessors, a combination of a digital signal processor (DSP), and a microprocessor, etc.

[0210] Communication interface 503 is used to connect to other devices via a communication network. This communication network can be Ethernet, wireless access network, wireless local area network (WLAN), etc.

[0211] The memory 501 may be a read-only memory (ROM) or other type of static storage device capable of storing static information and instructions, random access memory (RAM) or other type of dynamic storage device capable of storing information and instructions, or electrically erasable programmable read-only memory (EEPROM), disk storage medium or other magnetic storage device, or any other medium capable of carrying or storing desired program code in the form of instructions or data structures and accessible by a computer, but is not limited thereto.

[0212] In one possible implementation, the memory 501 can exist independently of the processor 502. The memory 501 can be connected to the processor 502 via a bus 504 and is used to store instructions or program code. When the processor 502 calls and executes the instructions or program code stored in the memory 501, it can implement the signal transmission method provided in the embodiments of this disclosure.

[0213] In another possible implementation, the memory 501 can also be integrated with the processor 502.

[0214] Bus 504 can be an extended industry standard architecture (EISA) bus, etc. Bus 504 can be divided into address bus, data bus, control bus, etc. For ease of illustration, only one thick line is used to represent it in Figure 12, but this does not mean that there is only one bus or one type of bus.

[0215] Some embodiments of this disclosure provide a computer-readable storage medium (e.g., a non-transitory computer-readable storage medium) storing computer program instructions that, when executed on a computer, cause the computer to perform a signal transmission method as described in any of the above embodiments.

[0216] In one exemplary embodiment, the computer may be the signal transmission device described above, and this disclosure does not limit the exemplary form of the computer.

[0217] In some examples, the aforementioned computer-readable storage media may include, but are not limited to: magnetic storage devices (e.g., hard disks, floppy disks, or magnetic tapes), optical discs (e.g., compact disks (CDs), digital versatile disks (DVDs), etc.), smart cards, and flash memory devices (e.g., erasable programmable read-only memory (EPROMs), cards, sticks, or key drives, etc.). The various computer-readable storage media described in this disclosure may represent one or more devices for storing information and / or other machine-readable storage media. The term "machine-readable storage media" may include, but is not limited to, wireless channels and various other media capable of storing, containing, and / or carrying instructions and / or data.

[0218] This disclosure provides a computer program product containing instructions that, when run on a computer, cause the computer to perform the signal transmission method described in any of the above embodiments.

[0219] The above description is merely a specific embodiment of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any changes or substitutions within the technical scope disclosed in this disclosure should be included within the scope of protection of this disclosure. Therefore, the scope of protection of this disclosure should be determined by the scope of the claims.

Claims

1. A signal transmission method applied to a first node, the method comprising: Determine the frequency domain resources to be used for transmitting the reference signal; The frequency domain resources are divided into X frequency domain resource groups, each of the X frequency domain resource groups contains at least one resource block, and the resource block includes at least one resource element, where X is a positive integer; For at least one of the K ports of the first node, determine the resource element occupied by the at least one port in the X frequency domain resource groups, where K is a positive integer greater than or equal to 1; as well as A reference signal is sent on the determined resource element through at least one of the K ports.

2. The method according to claim 1, wherein, When K is greater than 1, at least two of the K ports occupy different numbers of resource elements within the same or one frequency domain resource group.

3. The method according to claim 2, wherein, One of the at least two ports occupies zero resource elements within the same one or more frequency domain resource groups.

4. The method according to claim 1, wherein, At least one of the K ports occupies a different number of resource elements in at least two different frequency domain resource groups among the X frequency domain resource groups.

5. The method according to claim 1, wherein, The location and / or number of resource elements occupied by the at least one port are determined according to at least one of the following methods: The prior agreement between the first node and the second node; The signaling configuration of the first node; or Signaling configuration of the second node.

6. The method according to claim 1, wherein, When K is greater than 1, at least two of the K ports transmit their reference signals using code domain multiplexing.

7. The method according to claim 1, further comprising: When K is greater than 1, the K ports are divided into at least two groups of ports, each group of ports including at least one port, and the at least two groups of ports satisfy at least one of the following: There exists at least one set of ports where the number of resource elements occupied in a portion of the X frequency domain resource groups is 0, and the number of resource elements occupied in other frequency domain resource groups other than the portion of the frequency domain resource groups is greater than 0. There exists at least one group of ports in which the number of resource elements occupied in a portion of the frequency domain resource groups is greater than 0, and the number of resource elements occupied by other ports besides the at least one port group in the portion of the frequency domain resource groups is 0. Different ports within the same group of ports occupy the same number of resource elements within the same frequency domain resource group; or There exists at least one group of ports occupying resource elements in at least two different resource blocks within the same frequency domain resource group, but in different positions.

8. The method according to claim 1, wherein, The number of resource elements available for port occupancy is the same within each frequency domain resource group.

9. The method according to claim 1, wherein, The frequency domain resources are divided into the X frequency domain resource groups according to at least one of the following: The value of K; The prior agreement between the first node and the second node; The signaling configuration of the first node; or Signaling configuration of the second node.

10. The method according to claim 9, wherein, When the frequency domain resource group contains at least two resource blocks, the different resource blocks within the frequency domain resource group may be continuous or discontinuous in the frequency domain.

11. The method according to claim 10, wherein, When different resource blocks within the frequency domain resource group are not contiguous in the frequency domain, the number of resource blocks that separate adjacent resource blocks within the frequency domain resource group is the same.

12. The method according to claim 1, wherein, The value of X is determined according to at least one of the following: The value of K; The prior agreement between the first node and the second node; The signaling configuration of the first node; or Signaling configuration of the second node.

13. The method according to claim 1, wherein, The number of resource elements contained in at least one of the X frequency domain resource groups is determined according to at least one of the following: The value of K; The prior agreement between the first node and the second node; The signaling configuration of the first node; or Signaling configuration of the second node.

14. A signal transmission method applied to a second node, the method comprising: The system receives a reference signal transmitted by a first node on a determined resource element through at least one of K ports. The resource element includes the resource element occupied by at least one of the K ports in X frequency domain resource groups. The X frequency domain resource groups are obtained by dividing the frequency domain resources used for transmitting the reference signal. Each of the X frequency domain resource groups contains at least one resource block, and the resource block includes at least one resource element. X is a positive integer, and K is a positive integer greater than or equal to 1.

15. The method according to claim 14, wherein, At least one of the K ports occupies a different number of resource elements in at least two different frequency domain resource groups among the X frequency domain resource groups.

16. The method of claim 14, wherein, At least two of the K ports occupy different numbers of resource elements within the same or one frequency domain resource group.

17. The method according to claim 16, wherein, One of the at least two ports occupies 0 resource elements within the same one or more frequency domain resource groups.

18. The method according to claim 14, wherein, The position and / or number of resource elements occupied by at least one of the K ports in the X frequency domain resource groups are determined according to at least one of the following methods: The prior agreement between the first node and the second node; The signaling configuration of the first node; and Signaling configuration of the second node.

19. The method of claim 14, wherein, The number of resource elements available for port occupancy is the same within each frequency domain resource group.

20. The method of claim 14, wherein, When the frequency domain resource group contains at least two resource blocks, the different resource blocks within the frequency domain resource group may be continuous or discontinuous in the frequency domain.

21. The method according to claim 20, wherein, When different resource blocks within the frequency domain resource group are not contiguous in the frequency domain, the number of resource blocks that separate adjacent resource blocks within the frequency domain resource group is the same.

22. The method according to claim 14, wherein, The value of X is determined according to at least one of the following: The value of K; The prior agreement between the first node and the second node; The signaling configuration of the first node; or Signaling configuration of the second node.

23. The method according to claim 14, wherein, The number of resource elements contained in at least one of the X frequency domain resource groups is determined according to at least one of the following: The value of K; The prior agreement between the first node and the second node; The signaling configuration of the first node; or Signaling configuration of the second node.

24. A communication device, comprising: Memory and processor; The memory and the processor are coupled; The memory is used to store instructions that can be executed by the processor; When the processor executes the instructions, it performs the method as described in any one of claims 1 to 23.

25. A computer-readable storage medium, wherein, The computer-readable storage medium stores computer instructions that, when executed on a communication device, cause the communication device to perform the method as described in any one of claims 1 to 23.

26. A computer program product, wherein, When the computer program product is executed, it implements the method as described in any one of claims 1 to 23.

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