A method for calculating the center frequency of a 5G NR multi-resource grid

Abstract

The application discloses a 5G NR multi-resource grid center frequency calculation method and belongs to the field of information technology. The 5G NR multi-resource grid center frequency calculation method avoids repeatedly calculating from the resource grid with the largest subcarrier spacing, effectively solves the repeated calculation problem, and dynamically selects a new benchmark center frequency. When the number of resource grids of the network changes, the 5G NR multi-resource grid center frequency calculation method can effectively detect and handle resource conflict conditions by judging the number of subcarriers offset between the center frequency of each resource grid and the current center frequency. When the channel bandwidth of the network changes, the 5G NR multi-resource grid center frequency calculation method can effectively detect and handle resource conflict conditions by judging whether the transmission bandwidth of each resource grid is greater than the changed channel bandwidth, and whether the offset between the center frequency of the resource grid and the center frequency of the resource grid is greater than 1 resource block.

Description

Technical Field

[0001] This invention belongs to the field of information technology, specifically relating to a method for calculating the center frequency of a 5G NR multi-resource grid. Background Technology

[0002] Under the same channel bandwidth, 5G NR (New Radio) networks can be configured with multiple resource grids with different subcarrier spacings (SCS). During transmission across multiple resource grids, the same channel center frequency is used, and the center frequencies of each resource grid are distributed around the mid-frequency range of the entire channel bandwidth. According to protocol requirements, multiple resource grids need to be aligned; that is, the subcarrier 0 of a resource block (RB) in any resource grid with a larger SCS must be aligned with the subcarrier 0 of a certain RB in any resource grid with a smaller SCS. Since different resource grids contain different numbers of RBs, and the number of RBs is not linearly related to the SCS, there will be resource grid initial RB offsets and resource grid center frequency offsets relative to the channel center frequency. Researching the calculation methods for the channel center frequency, resource grid initial RB offset, and resource grid center frequency offset in multiple resource grids is of great significance for 5G NR signal simulation and resource location determination.

[0003] The current solution only uses the subcarrier spacing combination specified by the 3GPP protocol to calculate the center frequency of the multi-resource grid, and the calculation process depends on a fixed subcarrier spacing combination.

[0004] In the specific calculation of the center frequency of multiple resource grids, the existing scheme first uses the center frequency of the resource grid with the largest subcarrier spacing as the reference center frequency. Then, it calculates the frequency offset of the center frequencies of resource grids with smaller subcarrier spacings relative to the reference center frequency. If the current resource grid does not meet the requirement of {0, ±6} subcarriers between the center frequencies of each resource grid as specified in the 3GPP protocol, its center frequency is increased by increasing the initial RB offset of the current resource grid. In this operation, the number of subcarriers offset between the current resource grid center frequency and the reference center frequency is measured by the subcarrier offset of the current resource grid. For example, when the center frequency of a resource grid with a subcarrier spacing of 60kHz is used as the reference center frequency, the number of subcarriers offset by the center frequency of a resource grid with a subcarrier spacing of 30kHz relative to that center frequency is measured by 30kHz.

[0005] If, regardless of increasing the initial RB offset, the center frequency of a resource grid with a small subcarrier spacing cannot meet the requirement of an offset of {0, ±6} subcarriers between the center frequencies of all resource grids, then the initial RB offset of the resource grid with the largest subcarrier spacing is increased. The reference center frequency value is also increased accordingly. Then, the frequency offset of the center frequencies of the resource grids with smaller subcarrier spacings relative to the new reference center frequency is recalculated. This process is repeated until the offset between the center frequencies of all resource grids is {0, ±6} subcarriers.

[0006] The existing scheme is only applicable to subcarrier spacing combinations within the FR1 or FR2 bands specified in the 3GPP protocol. During the calculation process, the center frequency of the resource grid with the largest subcarrier spacing is always used as the reference center frequency. Even if a resource grid cannot meet the requirement of a center frequency offset of {0, ±6} subcarriers, the center frequency of the resource grid with the largest subcarrier spacing must be recalculated as the new reference center frequency, and then the frequency offsets of the resource grids with smaller subcarrier spacings relative to the new reference center frequency are calculated sequentially. This leads to unnecessary duplication of calculations. For example, when a resource grid with a smaller subcarrier spacing has a larger initial RB offset, resulting in a center frequency greater than the reference center frequency, this center frequency can be directly used as the new reference center frequency, and the initial RB offset of the resource grid with the larger subcarrier spacing can be increased, without needing to use the center frequency of the resource grid with the larger subcarrier spacing as the new reference center frequency.

[0007] Meanwhile, when the number of resource grids changes or the channel bandwidth changes due to network configuration, the offset between the center frequencies of each resource grid may not meet the requirements of {0, ±6} subcarriers, i.e., a collision occurs, and existing solutions do not have an effective collision detection mechanism.

[0008] In summary, the current method for calculating the center frequency of 5G NR multi-resource grid has the following shortcomings:

[0009] 1. It only applies to the subcarrier spacing combinations of the FR1 or FR2 frequency bands that are already defined in the 3GPP protocol. It cannot effectively calculate the center frequency for multi-resource grids composed of undefined or more general subcarrier spacing combinations, and its versatility is somewhat lacking.

[0010] 2. During the calculation process, since the center frequency of the resource grid with the largest subcarrier spacing is always used as the reference center frequency, unnecessary recalculation may occur, which not only increases the computational complexity but also affects the computational efficiency.

[0011] 3. Lack of an effective collision detection mechanism. When the number of resource grids or channel bandwidth changes, it is impossible to effectively detect whether the offset between the center frequencies of each resource grid meets the requirement of {0, ±6} subcarriers. Summary of the Invention

[0012] In view of the above-mentioned technical problems in the existing technology, the present invention proposes a 5G NR multi-resource grid center frequency calculation method, which is reasonably designed, overcomes the shortcomings of the existing technology, and has good effect.

[0013] To achieve the above objectives, the present invention adopts the following technical solution:

[0014] A method for calculating the center frequency of a 5G NR multi-resource grid cell is proposed, where the channel bandwidth of the 5G NR cell is B, the number of resource grids is N (N≥2), and the number of resource blocks (RB) in each resource grid is L. i Where i = 0, ..., N-1; the subcarrier spacing is S. i S i They are all different; the starting RB offset of resource grid i is X. i Its center frequency is f i According to the channel resource allocation principles in the communication process, X i The value should satisfy 12*X i *S i +12*L i *S i ≤B; The offset of the center frequency of resource grid i relative to the channel center frequency is d. i There are 1 subcarrier, and according to the 3GPP protocol, when the resource grid is aligned, there are d i ∈{0,±6}, and f i =(12*L) i *S i ) / 2+12*X i *S i +d i *S i ;

[0015] Specifically, the steps include the following:

[0016] Step 1: Calculate the channel center frequency;

[0017] Step 2: Conflict detection when the number of resource grids changes;

[0018] By determining the number of subcarriers offset between the center frequency of each resource grid and the current center frequency, resource conflicts can be effectively detected and handled.

[0019] Step 3: Collision detection when channel bandwidth changes;

[0020] By determining whether the transmission bandwidth of each resource grid is greater than the changed channel bandwidth, and whether the offset between the intermediate frequency of the channel bandwidth and the center frequency of the resource grid is greater than one resource block, resource conflicts can be effectively detected and handled.

[0021] Preferably, step 1 specifically includes the following steps:

[0022] Step 1.1: Calculate the initial center frequency of each resource grid. If they are not all the same, record the resource grid with the largest initial center frequency.

[0023] Step 1.2: Starting from the i=0th resource grid, sequentially allocate X... i Increment the value by 1, and update the resource grid with the highest center frequency;

[0024] Step 1.3: Repeat steps 1.1-1.2 until a subcarrier with an offset of 0 or ±6 resource grid i between the center frequency of resource grid m and resource grid i is found. At this point, the center frequency of resource grid m is the channel center frequency; when the X of a resource grid... i The value makes 12*X i *S i +12*S i *L i When the resource grid resources exceed the channel bandwidth, it is considered that the channel center frequency has not been found.

[0025] Preferably, step 2 specifically includes the following steps:

[0026] Step 2.1: Sequentially determine the number of subcarriers offset between the center frequency of each resource grid and the current center frequency. If any of these offsets exceed the range of {0, ±6}, then a conflict is considered to exist.

[0027] Step 2.2: Recalculate the starting RB and subcarrier offset values ​​for each resource grid.

[0028] Preferably, step 3 specifically includes the following steps:

[0029] Step 3.1: Sequentially determine whether the transmission bandwidth of each resource grid is greater than the changed channel bandwidth, and whether the offset between the intermediate frequency of the channel bandwidth and the center frequency of the resource grid is greater than one resource block. If either of these conditions exists, a conflict is considered to exist.

[0030] Step 3.2: Recalculate the starting RB and subcarrier offset values ​​for each resource grid.

[0031] The beneficial technical effects of this invention are as follows:

[0032] 1. The 5G NR multi-resource grid center frequency calculation method proposed in this invention is not limited by specific subcarrier spacing and the number of RBs. It is not only compatible with the fixed subcarrier spacing combination described in the existing 3GPP protocol, but also has a certain degree of scalability for protocol evolution and technology development.

[0033] 2. The 5G NR multi-resource grid center frequency calculation method proposed in this invention effectively solves the problem of redundant calculation by dynamically selecting a new reference center frequency and avoiding repeated calculations starting from the resource grid with the largest subcarrier spacing.

[0034] 3. The 5G NR multi-resource grid center frequency calculation method proposed in this invention can effectively detect and handle resource conflicts when the number of resource grids in the network changes by judging the number of subcarriers offset between the center frequency of each resource grid and the current center frequency.

[0035] 4. The 5G NR multi-resource grid center frequency calculation method proposed in this invention can effectively detect and handle resource conflicts when the channel bandwidth of the network changes. This is achieved by determining whether the transmission bandwidth of each resource grid is greater than the changed channel bandwidth and whether the offset between the intermediate frequency of the channel bandwidth and the center frequency of the resource grid is greater than one resource block. Attached Figure Description

[0036] Figure 1 Here is a flowchart for calculating the channel center frequency;

[0037] Figure 2 Flowchart of the resource conflict determination method when the number of resource grids changes;

[0038] Figure 3 This is a flowchart of a method for determining resource conflicts when channel bandwidth changes. Detailed Implementation

[0039] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0040] Let B be the channel bandwidth of a 5G NR cell, and N be the number of resource grids, where N ≥ 2. Let L be the number of resource blocks (RBs) in each resource grid. i (i = 0, ..., N-1), the subcarrier spacing (SCS) is S i (i = 0, ..., N-1), S i They are all different. The starting RB offset of resource grid i is X. i Its center frequency is f i According to the channel resource allocation principles in the communication process, X i The value should satisfy 12*X i *S i +12*L i *S i ≤B. The offset of the center frequency of resource grid i relative to the channel center frequency is d. i There are 1 subcarrier, and according to the 3GPP protocol, when the resource grid is aligned, there are d i ∈{0,±6}, and f i =(12*i *S i ) / 2+12*X i *S i +d i *S i .

[0041] According to the 3GPP protocol, for 5G NR cells operating in the FR1 and FR2 frequency bands, the relationship between the number of SCS and RBs of resource grid i under different channel bandwidths is shown in Tables 1 and 2, respectively. In the tables, N / A indicates that the corresponding SCS is not supported under that channel bandwidth, meaning that the resource grid for that SCS does not exist. As can be seen from the two tables, regardless of the FR1 or FR2 frequency band, under the same channel bandwidth, the larger the resource grid SCS, the smaller its number of RBs, and the smaller the resource grid L of the SCS... i *S i The value is not less than the L of the resource grid with a larger SCS. i *S i On the other hand, with the same resource grid SCS, the larger the channel bandwidth, the larger the number of RBs.

[0042] Table 1

[0043]

[0044] Table 2

[0045]

[0046] 1. Channel center frequency calculation

[0047] In this scheme, the channel center frequency calculation is assumed to be known, including the channel bandwidth, the number of resource grids, the number of RBs in each resource grid, and the SCS. Based on the principle that multiple resource grids share the same channel center frequency, it is assumed that X... i The initial values ​​of all (i = 0, ..., N-1) are 0, and then the X values ​​of some resource grids are adjusted appropriately. i The value is maintained until the channel center frequency of all resource grids is the same, at which point the offset of the center frequency of each resource grid relative to the channel center frequency is 0 or ±6 subcarriers.

[0048] First, calculate the initial center frequency of each resource grid. If they are not all the same, record the resource grid with the largest initial center frequency. Then, starting from the i=0th resource grid, sequentially assign X... i Increment the value by 1, and simultaneously update the resource grid with the largest center frequency. Repeat the above steps until a subcarrier is found whose center frequency of resource grid m is offset from the center frequency of resource grid i by 0 or ±6 resource grid i. At this point, the center frequency of resource grid m is the channel center frequency. When the X of a resource grid... iThe value makes 12 * X i * S i + 12 * S i * L i > B, the resource grid resources exceed the channel bandwidth, and it is considered that the channel center frequency is not found.

[0049] The detailed steps (the process is as Figure 1 shown) are described as follows:

[0050] 1) Initialize i = 0, m = 0;

[0051] 2) If i < N, then set X i = 0, f i = 6 * L i * S i + 12 * X i * S i , and execute 3); otherwise execute 5);

[0052] 3) If f i > f m , then set m = i;

[0053] 4) i = i + 1, and execute 2);

[0054] 5) Set i = 0;

[0055] 6) If i < N, then execute 7); otherwise execute 10);

[0056] 7) g = 12 * X i * S i + 12 * L i * S i

[0057] 8) If g ≤ B, then execute 9); otherwise execute 11); <​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​i , execute 7);

[0059] 10) Output f m is the center frequency of the channel, and output the X i value and d i value, execute 12);

[0060] 11) The center frequency of the channel is not found;

[0061] 12) End.

[0062] where abs() is the absolute value function:

[0063] 2. Conflict Judgment and Resolution Method

[0064] When the number of resource grids changes, the offsets between the center frequencies of the resource grids and the center frequency of the channel may not all be 0 or ±6 subcarriers, resulting in resource conflicts. When the channel bandwidth changes, since the intermediate frequency of the entire channel bandwidth changes, the offset between the intermediate frequency of the channel bandwidth and the center frequency of the resource grid is greater than 1 resource block. Therefore, the center frequency of the channel needs to be recalculated; on the other hand, the sum of the number of RBs of the resource grid and the starting RB offset may be greater than the new channel bandwidth, resulting in resource conflicts. The resource conflict judgment methods after the changes in the number of resource grids and the channel bandwidth are described below.

[0065] Denote the number of resource grids after the change as N′, and the center frequencies, the number of RBs, and the SCS of the newly added resource grids are f i (i = N,..., N′ - 1), L i (i = N,..., N′ - 1), and S i (i = N,..., N′ - 1), and the offset of the center frequency relative to the center frequency of the channel is d i subcarriers. Before conflict resolution, the starting RB offset X i of the newly added resource grid is 0. Therefore, the center frequency f i of the newly added resource grid is (12 * L i * S i ) / 2 + d i * S i .

[0066] The detailed steps for judging resource conflicts (the process is as Figure 2 shown) are described as follows:

[0067] 1) Initialize i = 0;

[0068] 2) If i < N′, then execute 3); otherwise end;

[0069] 3) d i = (f i-f m ) / S i ;

[0070] 4) If d i ≠0 and abs(d i )≠6, there is a resource conflict in resource grid i;

[0071] 5) i = i + 1, execute 2).

[0072] Where abs() is the absolute value function.

[0073] Denote the changed channel bandwidth as B′. The detailed steps for judging resource conflict (the process is as Figure 3 shown) are described as follows:

[0074] 1) Initialize i = 0;

[0075] 2) If i < N, execute 3); otherwise end;

[0076] 3) g = 12 * X i * S i + 12 * L i * S i ;

[0077] 4) If g > B′ or abs(f i - B′ / 2) > 12 * S i , there is a resource conflict in resource grid i;

[0078] 5) i = i + 1, execute 2).

[0079] Where abs() is the absolute value function.

[0080] When the number of resource grids or the channel bandwidth changes, if there is a resource conflict in at least one resource grid, recalculate the channel center frequency, as well as the X i values and d i values of each resource grid using the method described in Part 1.

[0081] Key Points and Protection Points 1 A General Method for Calculating the Center Frequency of 5G NR Multi-Resource Grids

[0082] Based on the analysis of the subcarrier spacing combinations specified in the 3GPP protocol, the present invention proposes a general method for calculating the center frequency of 5G NR multi-resource grids, which is applicable to various situations where there is no linear relationship between the subcarrier spacing and the center frequency. This method not only is compatible with the fixed subcarrier spacing combinations described in the existing 3GPP protocol, but also has certain scalability for protocol evolution and technological development.

[0083] Key point and protection point 2: During the center frequency calculation process, the maximum center frequency is dynamically selected as the reference center frequency to avoid repeated calculations.

[0084] The 5G NR multi-resource grid center frequency calculation method proposed in this invention finds the maximum center frequency of each resource grid as the reference center frequency during the initialization phase. In subsequent calculations, as the initial RB offset of each resource grid increases, if the center frequency of a certain resource grid is greater than the reference center frequency, the center frequency of that resource grid is dynamically used as the new reference center frequency. This avoids repeatedly starting the calculation from the resource grid with the largest subcarrier spacing, effectively solving the problem of redundant calculations.

[0085] Key Points and Protection Points 3: Scalable and Efficient 5G NR Multi-Resource Mesh Center Frequency Calculation Method

[0086] The method proposed in this invention uses a symbolic approach to describe the calculation process of the center frequency of multiple resource grids with different subcarrier spacings, resource block numbers, and starting RB offsets. It is not limited by specific subcarrier spacings and RB numbers, and possesses good versatility and scalability. Furthermore, by dynamically selecting a new reference center frequency during the calculation process, redundant calculations can be avoided, allowing for the rapid acquisition of the center frequencies of multiple resource grids.

[0087] Critical Points and Protection Points 4: Conflict Detection Method When Resource Grid Quantity Changes

[0088] The 5G NR multi-resource grid center frequency calculation method proposed in this patent can effectively detect resource conflicts when the number of resource grids changes. When the number of resource grids changes, the offset between the center frequency of each resource grid and the current center frequency may not all be 0 or ±6 subcarriers, which is considered a resource conflict. In this case, the number of subcarriers offset between the center frequency of each resource grid and the current center frequency is determined sequentially. If any offset exceeds the range of {0, ±6}, a conflict is considered to exist. Then, the aforementioned center frequency calculation method is used to recalculate the initial RB and subcarrier offset values ​​of each resource grid.

[0089] Key Points and Protection Points: Collision Detection Methods When Channel Bandwidth Changes

[0090] The 5G NR multi-resource grid center frequency calculation method proposed in this patent can effectively detect resource conflicts when the channel bandwidth changes. Changes in channel bandwidth cause a change in the intermediate frequency of the entire channel. If the offset between the intermediate frequency and the current center frequency is greater than one resource block, the channel center frequency must be recalculated. On the other hand, the sum of the number of resource grid blocks (RBs) and the initial RB offset may be greater than the changed channel bandwidth, leading to resource conflicts. In this case, the method sequentially checks whether the transmission bandwidth of each resource grid is greater than the changed channel bandwidth and whether the offset between the intermediate frequency of the channel bandwidth and the center frequency of the resource grid is greater than one resource block. If either of these conditions exists, a conflict is considered to exist, and the aforementioned center frequency calculation method is used to recalculate the initial RB and subcarrier offset values ​​for each resource grid.

[0091] Of course, the above description is not intended to limit the present invention, and the present invention is not limited to the examples given above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A method for calculating the center frequency of a 5G NR multi-resource grid, characterized in that: Let the channel bandwidth of the 5G NR cell be... The number of resource grids is ,in The number of RBs in each resource grid is ,in, The subcarrier spacing is , Different; resource grid The starting RB offset is Its center frequency is According to the channel resource allocation principles in the communication process, The value should satisfy Resource grid The offset of the center frequency relative to the channel center frequency is There are several subcarriers, and according to the 3GPP protocol, when the resource grid is aligned, there are... ,and ; Specifically, the steps include the following: Step 1: Calculate the channel center frequency; Step 2: Conflict detection when the number of resource grids changes; By determining the number of subcarriers offset between the center frequency of each resource grid and the channel center frequency calculated in step 1, resource conflicts can be effectively detected and handled. Step 3: Collision detection when channel bandwidth changes; By determining whether the transmission bandwidth of each resource grid is greater than the changed channel bandwidth, and whether the offset between the intermediate frequency of the channel bandwidth and the center frequency of the resource grid is greater than one resource block, resource conflicts can be effectively detected and handled. Step 1 specifically includes the following steps: Step 1.1: Calculate the initial center frequency of each resource grid. If they are not all the same, record the resource grid with the largest initial center frequency. Step 1.2: From the first Starting with one resource grid, sequentially... Increment the value by 1, and update the resource grid with the highest center frequency; Step 1.3: Repeat steps 1.1-1.2 until a resource grid is found. Center frequency and resource grid The offset between center frequencies is 0 or ±6 resource grids. The subcarrier, at this time the resource grid The center frequency is the channel center frequency; when a resource grid's... The value makes At that time, the resource grid resources exceeded the channel bandwidth, and it was determined that the channel center frequency had not been found.

2. The 5G NR multi-resource grid center frequency calculation method according to claim 1, characterized in that: Step 2 specifically includes the following steps: Step 2.1: Sequentially determine the number of subcarriers offset between the center frequency of each resource grid and the current center frequency. If there are more than [number of subcarriers], [then the process continues]. If the scope is limited, then a conflict is considered to exist; Step 2.2: Recalculate the starting RB and subcarrier offset values ​​for each resource grid.

3. The 5G NR multi-resource grid center frequency calculation method according to claim 1, characterized in that: Step 3 specifically includes the following steps: Step 3.1: Sequentially determine whether the transmission bandwidth of each resource grid is greater than the changed channel bandwidth, and whether the offset between the intermediate frequency of the channel bandwidth and the center frequency of the resource grid is greater than one resource block. If either of these conditions exists, a conflict is considered to exist. Step 3.2: Recalculate the starting RB and subcarrier offset values ​​for each resource grid.

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