5G NR multi-resource grid center frequency calculation method

Abstract

The invention discloses a 5G NR multi-resource grid center frequency calculation method, and belongs to the technical field of information. According to the 5G NR multi-resource grid center frequency calculation method provided by the invention, the new reference center frequency is dynamically selected, so that calculation is prevented from being repeatedly started from the resource grid with the maximum subcarrier interval, and the problem of repeated calculation is effectively solved; according to the 5G NR multi-resource grid center frequency calculation method provided by the invention, when the number of resource grids of a network is changed, the resource conflict condition can be effectively detected and processed by judging the number of offset subcarriers between the center frequency of each resource grid and the current center frequency; according to the 5GNR multi-resource grid center frequency calculation method provided by the invention, when the channel bandwidth of the network is changed, whether the transmission bandwidth of each resource grid is greater than the changed channel bandwidth or not is judged, 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 or not is judged; the resource conflict condition can be effectively detected and processed.

Description

Technical Field

[0001] The present invention belongs to the field of information technology, and in particular relates to a method for calculating the center frequency of a 5G NR multi-resource grid. Background Art

[0002] Under the same channel bandwidth, the 5G NR (New Radio) network can be configured with multiple resource grids with different subcarrier spacing (SCS). During the transmission of multiple resource grids, the channel center frequency used is the same, and the center frequency positions of each resource grid are distributed around the middle frequency of the entire channel bandwidth. According to the protocol requirements, multiple resource grids need to be aligned, that is, the subcarrier 0 of the resource block (RB) in any resource grid of a larger SCS is aligned with the subcarrier 0 of a certain RB in the resource grids of all smaller SCSs. Since different resource grids contain different numbers of RBs, and the number of RBs is not linearly related to the SCS, there will be situations where the starting RB of the resource grid is offset and the center frequency of the resource grid is offset relative to the channel center frequency. Studying the calculation method of the channel center frequency of multiple resource grids, the starting RB offset of the resource grid, and the center frequency offset of the resource grid is of great significance to 5G NR signal simulation and resource location determination.

[0003] The current solution only uses the subcarrier spacing combination specified in 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 process of calculating the center frequencies of multiple resource grids, the existing scheme first takes the center frequency of the resource grid with the largest subcarrier spacing as the reference center frequency, and then calculates the frequency offset of the center frequency of the resource grid with smaller subcarrier spacing relative to the reference center frequency in turn. If the current resource grid does not meet the requirement of the 3GPP protocol that the offset between the center frequencies of each resource grid is {0, ±6} subcarriers, then the center frequency is increased by increasing the starting RB offset of the current resource grid. In this operation, the number of subcarriers offset between the center frequency of the current resource grid and the reference center frequency is measured by the subcarrier offset of the current resource grid. For example, when the center frequency of the resource grid with a subcarrier spacing of 60kHz is used as the reference center frequency, the number of subcarriers offset between the center frequency of the resource grid with a subcarrier spacing of 30kHz and the center frequency is measured as 30kHz.

[0005] If the center frequency of a resource grid with a small subcarrier spacing cannot meet the requirement that the center frequency of each resource grid is offset by {0, ±6} subcarriers no matter how the starting RB offset is increased, then the starting RB offset of the resource grid with the largest subcarrier spacing is increased, and the reference center frequency value is also increased accordingly, and then the frequency offset of the center frequency of the resource grid with a smaller subcarrier spacing relative to the new reference center frequency is recalculated in sequence. Repeat the above operation until the center frequency of each resource grid is offset by {0, ±6} subcarriers.

[0006] The existing scheme is only applicable to the subcarrier spacing combination of the FR1 frequency band or the FR2 frequency band specified by 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 there is a resource grid that cannot meet the requirement of the 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 offset of the center frequency of the resource grid with a smaller subcarrier spacing relative to the new reference center frequency is calculated in turn. This will lead to unnecessary repeated calculations. For example, when the center frequency of the resource grid with a smaller subcarrier spacing is greater than the reference center frequency due to a large starting RB offset, the center frequency can be directly used as the new reference center frequency, and the starting RB offset of the resource grid with a larger subcarrier spacing can be increased, without using the center frequency of the resource grid with a larger subcarrier spacing as the new reference center frequency.

[0007] At the same time, 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 requirement of {0,±6} subcarriers, that is, a conflict occurs, and the existing scheme does not have an effective conflict detection mechanism.

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

[0009] 1. It only targets the subcarrier spacing combinations of the FR1 or FR2 frequency bands that have been defined by the 3GPP protocol. It is impossible to effectively calculate the center frequency of the multi-resource grid composed of undefined or more general subcarrier spacing combinations, and lacks universality.

[0010] 2. In the calculation process, since the center frequency of the resource grid with the maximum subcarrier spacing is always used as the reference center frequency, unnecessary repeated calculations may be caused, which not only increases the calculation complexity but also affects the calculation efficiency.

[0011] 3. There is a lack of effective conflict detection mechanism. When the number of resource grids or the 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 existing in the prior art, the present invention proposes a 5G NR multi-resource grid center frequency calculation method, which has a reasonable design, overcomes the shortcomings of the prior art, and has good effects.

[0013] In order to achieve the above object, the present invention adopts the following technical solution:

[0014] A method for calculating the center frequency of 5G NR multi-resource grids, where the channel bandwidth of the 5G NR cell is B, the number of resource grids is N, where N ≥ 2, and the number of resource blocks RBs of each resource grid is L i , where i = 0…, N-1; the subcarrier spacing is S i , S i Different; the starting RB offset of resource grid i is X i , whose center frequency is f i ; According to the channel resource allocation principle 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 center frequency of the channel is d i subcarriers, 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] The specific steps include:

[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: Conflict detection when channel bandwidth changes;

[0020] By judging 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 frequencies 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, i The value is increased by 1, and the resource grid with the maximum center frequency is updated at the same time;

[0024] Step 1.3: Repeat steps 1.1-1.2 until a subcarrier whose center frequency of a resource grid m is offset from the center frequency of resource grid i by 0 or ±6 subcarriers of resource grid i is found. At this time, the center frequency of resource grid m is the channel center frequency. i The value is such that 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 has not been found.

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

[0026] Step 2.1: Determine the number of subcarriers offset between the center frequency of each resource grid and the current center frequency in turn. If there is a situation that exceeds the range of {0, ±6}, it is considered that there is a conflict;

[0027] Step 2.2: Recalculate the starting RB and subcarrier offset value of each resource grid.

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

[0029] Step 3.1: Determine in turn whether the transmission bandwidth of each resource grid is greater than the changed channel bandwidth, and whether the offset between the middle frequency of the channel bandwidth and the center frequency of the resource grid is greater than 1 resource block. If any of these situations exists, it is considered that there is a conflict;

[0030] Step 3.2: Recalculate the starting RB and subcarrier offset value of each resource grid.

[0031] Beneficial technical effects brought by the present invention:

[0032] 1. The 5G NR multi-resource grid center frequency calculation method proposed in the present invention is not limited by the 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 certain scalability for protocol evolution and technology development.

[0033] 2. The 5G NR multi-resource grid center frequency calculation method proposed in the present invention dynamically selects a new reference center frequency to avoid repeatedly starting calculation from the resource grid with the largest subcarrier spacing, effectively solving the problem of repeated calculation.

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

[0035] 4. The 5G NR multi-resource grid center frequency calculation method proposed in the present invention can effectively detect and handle resource conflicts when the channel bandwidth of the network changes by judging 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 1 resource block. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 Flow chart for calculating the channel center frequency;

[0037] Figure 2 A flow chart of a method for determining resource conflicts when the number of resource grids changes;

[0038] Figure 3 The present invention is a flow chart of a method for determining resource conflicts when channel bandwidth changes. DETAILED DESCRIPTION

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

[0040] The channel bandwidth of the 5G NR cell is B, the number of resource grids is N, where N ≥ 2. The number of RBs in each resource grid is L i (i=0…,N-1), subcarrier spacing (SCS) is S i (i=0,…,N-1), S i The starting RB offset of resource grid i is X i , whose center frequency is f i According to the channel resource allocation principle in the communication process, X i The value should satisfy 12*X i *S i +12*L i *S i ≤B. The center frequency of resource grid i is offset from the center frequency of the channel by d i subcarriers, 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 SCS and the number of RBs of resource grid i under different channel bandwidths is shown in Table 1 and Table 2, respectively. N / A in the table means that the corresponding SCS is not supported under the channel bandwidth, that is, there is no resource grid with the SCS. It can be seen from the two tables that regardless of the FR1 or FR2 frequency band, under the same channel bandwidth, the larger the resource grid SCS, the smaller the number of RBs and the L of the resource grid with a smaller SCS is. i *S i The value is not less than L of the resource grid of the larger SCS i *S i On the other hand, when the resource grid SCS is the same, 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 the process of calculating the channel center frequency in this scheme, it is assumed that the channel bandwidth, the number of resource grids, the number of RBs in each resource grid, the SCS and other parameters are all known. According to the principle that multiple resource grids have the same channel center frequency, it is assumed that X i The initial value of (i=0,…,N-1) is 0, and then the X of some resource grids is adjusted appropriately. i The value is set until the channel center frequencies of all resource grids are the same, at which point the center frequency of each resource grid is offset from the channel center frequency by 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 convert X i The value is increased by 1, and the resource grid with the largest center frequency is updated at the same time. Repeat the above steps until a subcarrier whose center frequency of a resource grid m is offset from the center frequency of resource grid i by 0 or ±6 subcarriers of resource grid i is found. At this time, the center frequency of resource grid m is the channel center frequency. 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 let X i = 0, f i = 6 * L i * S i + 12 * X i * S i , execute 3); otherwise execute 5);

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

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

[0054] 5) Let 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);

[0058] 9) If f m - f i = 0 or abs(f m - f i ) = 6 * S i , then let d i = (f i - f m ) / S i , i = i + 1, execute 6); otherwise if f i > f m , then let m = i, execute 5); otherwise let X i = X i + 1, f i = 6 * L i * S i + 12 * X i * Si , execute 7);

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

[0060] 11) The channel center frequency 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 channel center frequency 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, it is necessary to recalculate the channel center frequency; 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 channel center frequency 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 = (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′, and 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] After the number of resource grids or the channel bandwidth changes, if there is a resource conflict in at least one resource grid, use the method described in Part 1 to recalculate the channel center frequency and the X i values and d i values of each resource grid.

[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 sub - carrier 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 the cases where there is no linear relationship between various sub - carrier spacings and the center frequency. This method not only is compatible with the fixed sub - carrier spacing combinations described in the existing 3GPP protocol, but also has a certain scalability for protocol evolution and technological development.

[0083] During the center frequency calculation process, the key point and protection point 2 dynamically select the maximum center frequency as the reference center frequency to avoid repeated calculations.

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

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

[0086] The method proposed in the present invention uses a symbolic method to describe the calculation process of the center frequencies of multiple resource grids with different subcarrier spacings, resource block numbers, and starting RB offsets, and is not limited by the specific subcarrier spacing and RB number, and has good versatility and scalability. At the same time, in the calculation process, by dynamically selecting a new reference center frequency, repeated calculations can be avoided, and the center frequencies of multiple resource grids can be quickly obtained.

[0087] Conflict detection method for key points and protection points 4 when the number of resource grids 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 be all 0 or ±6 subcarriers, which is considered a resource conflict. At this time, the number of subcarriers offset between the center frequency of each resource grid and the current center frequency is determined in turn. If there is a situation beyond the range of {0, ±6}, it is considered that there is a conflict, and then the starting RB and subcarrier offset value of each resource grid are recalculated using the aforementioned center frequency calculation method.

[0089] Conflict detection method when the bandwidth of key point and protection point 5 channels 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 will cause changes in the middle frequency of the entire channel. The offset between the middle frequency of the channel and the current center frequency is greater than 1 resource block, so the channel center frequency must be recalculated; on the other hand, the sum of the number of RBs in the resource grid and the starting RB offset may be greater than the changed channel bandwidth, resulting in resource conflicts. At this time, it is determined in turn whether the transmission bandwidth of each resource grid is greater than the changed channel bandwidth, and whether the offset between the middle frequency of the channel bandwidth and the center frequency of the resource grid is greater than 1 resource block. If one of these situations exists, it is considered that there is a conflict, and then the starting RB and subcarrier offset values ​​of each resource grid are recalculated using the aforementioned center frequency calculation method.

[0091] Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by technicians in this technical field within the essential scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A 5G NR multi-resource grid center frequency calculation method, characterized in that: The channel bandwidth of the 5G NR cell is B, the number of resource grids is N, where N ≥ 2, and the number of RBs in each resource grid is L i , where i = 0…, N-1; the subcarrier spacing is S i , S i Different; the starting RB offset of resource grid i is X i , whose center frequency is f i ; According to the channel resource allocation principle 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 center frequency of the channel is d i subcarriers, 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 ; The specific steps include: 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 current center frequency, resource conflicts can be effectively detected and handled; Step 3: Conflict detection when channel bandwidth changes; By judging 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.

2. The 5G NR multi-resource grid center frequency calculation method according to claim 1, characterized in that: Step 1 specifically includes the following steps: Step 1.1: Calculate the initial center frequencies of each resource grid. If they are not all the same, record the resource grid with the largest initial center frequency. Step 1.2: Starting from the i=0th resource grid, i The value is increased by 1, and the resource grid with the maximum center frequency is updated at the same time; Step 1.3: Repeat steps 1.1-1.2 until a subcarrier whose center frequency of a resource grid m is offset from the center frequency of resource grid i by 0 or ±6 subcarriers of resource grid i is found. At this time, the center frequency of resource grid m is the channel center frequency. i The value is such that 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 has not been found.

3. 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: Determine the number of subcarriers offset between the center frequency of each resource grid and the current center frequency in turn. If there is a situation that exceeds the range of {0, ±6}, it is considered that there is a conflict; Step 2.2: Recalculate the starting RB and subcarrier offset value of each resource grid.

4. 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: Determine in turn whether the transmission bandwidth of each resource grid is greater than the changed channel bandwidth, and whether the offset between the middle frequency of the channel bandwidth and the center frequency of the resource grid is greater than 1 resource block. If any of these situations exists, it is considered that there is a conflict; Step 3.2: Recalculate the starting RB and subcarrier offset value of each resource grid.

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