A data transmission method and base station

Abstract

The present invention is applicable to the field of wireless communication technology, and provides a data transmission method and a base station using the method, including: RHUB receives RE data sent by a baseband processing unit BBU, and caches the RE data, wherein the RE data carries a symbol number; the RHUB generates a control signal synchronously with the RE data sent by the BBU, and the control signal has the same symbol number as the initial data of the RE data; the RHUB controls the reading of the cached RE data based on the comparison between the control signal and the symbol number of the RE data, and sends the read RE data to a radio remote unit RRU to align the delay. The present invention can solve the problem of delay misalignment that occurs during transmission between the existing BBU and RRU, and improve the accuracy and robustness of data transmission.

Description

Technical Field

[0001] The present invention belongs to the technical field of wireless communications, and in particular relates to a data transmission method and a base station between a BBU and an RRU. Background Art

[0002] In the existing wireless communication system, there are usually indoor baseband processing units (Building Base bandUnite, BBU) and radio remote units (Remote Radio Unit, RRU), and the communication between BBU and RRU often requires corresponding processing of data. Take the frequency domain resource element (RE) data of the enhanced common public radio interface eCPRI protocol as an example to illustrate that when the BBU uses the eCPRI protocol to send RE data to the RRU, the RE data needs to be inverse fast Fourier transform IFFT (Inverse Fast Fourier Transform, inverse fast Fourier transform), and add a cyclic prefix (CP) to the transformed RE data, and the above processing requires a certain processing time. Therefore, during the data transmission process, there is a certain delay between the BBU and the RRU, and the length of the above delay is related to the processing time required for the data.

[0003] The existing data transmission technology between BBU and RRU is prone to RE data loss or processing timeout due to complex structure, insufficient processing capability or abnormalities during transmission, resulting in latency misalignment. Summary of the invention

[0004] In view of this, an embodiment of the present invention provides a method and a base station for data transmission between a BBU and an RRU, so as to solve the problem of time delay misalignment in the existing data transmission technology between a BBU and an RRU.

[0005] A first aspect of an embodiment of the present invention provides a downlink data transmission method, including:

[0006] The radio remote hub RHUB receives the RE data sent by the baseband processing unit BBU and caches the RE data, wherein the RE data carries a symbol number;

[0007] The RHUB generates a control signal synchronously with the BBU sending the RE data, and the control signal has the same symbol number as the initial data of the RE data;

[0008] The RHUB controls the reading of the buffered RE data based on the comparison between the control signal and the symbol number of the RE data, and sends the read RE data to the remote radio unit RRU to align the delays.

[0009] A second aspect of an embodiment of the present invention provides a radio remote hub RHUB, including:

[0010] A receiving module is used to receive RE data sent by a baseband processing unit BBU;

[0011] A cache module, used for caching the RE data, wherein the RE data carries a symbol number;

[0012] A control module, configured to generate a control signal synchronously with the RE data sent by the BBU, wherein the control signal has the same symbol number as the initial data of the RE data; the control module is further configured to control the reading of the RE data based on a comparison between the control signal and the symbol number of the RE data;

[0013] The sending module is used to send the read RE data to the radio remote unit RRU to align the delay.

[0014] A third aspect of the embodiments of the present invention provides a base station, comprising: at least one BBU, at least one RHUB provided by the second aspect, and at least one RRU.

[0015] A fourth aspect of an embodiment of the present invention provides an uplink data transmission method, wherein a first RHUB and a second RHUB are cascaded between a BBU and an RRU; wherein the first RHUB is an uplink RHUB of the second RHUB;

[0016] The uplink data transmission method comprises:

[0017] If the first RHUB detects the cached first uplink data sent by the RRU, starting a waiting window;

[0018] The first RHUB controls merging of the first uplink data and the second uplink data based on whether the second uplink data uploaded by the second RHUB is received within the waiting window, and sends the first uplink data or data combined with the first uplink data and the second uplink data to the BBU to align delays.

[0019] A fifth aspect of an embodiment of the present invention provides a base station, the base station comprising: at least one BBU, a first RHUB, an RRU connected to the first RHUB, a second RHUB, and an RRU connected to the second RHUB; wherein the first RHUB is an uplink RHUB of the second RHUB;

[0020] The first RHUB is configured to start a waiting window if the cached first uplink data sent by the RRU is detected;

[0021] The first RHUB is configured to control merging of the first uplink data and the second uplink data based on whether the second uplink data uploaded by the second RHUB is received within the waiting window, and send the first uplink data or data combined with the first uplink data and the second uplink data to the BBU to align the delays.

[0022] A sixth aspect of an embodiment of the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method described in the first aspect and / or the method described in the fourth aspect is implemented.

[0023] The method and electronic device for data transmission between a BBU and an RRU provided by the embodiment of the present invention have the following beneficial effects:

[0024] In the embodiment of the present invention, during the process of executing the downlink data service from BBU to RRU, the RE data sent by BBU to RHUB will carry a symbol number, and when RHUB receives the RE data sent by BBU, it will also generate a control signal synchronously with the RE data sent by BBU, and the control signal has the same symbol number as the RE data. RHUB identifies whether the delay between BBU and RHUB is aligned by comparing whether the symbol numbers of RE data and control signal are consistent, and controls the reading of cached RE data based on the delay alignment, and sends the read RE data to the radio remote unit RRU to align the delay, thereby solving the problem of delay misalignment that occurs during transmission between existing BBU and RRU, and improving the accuracy and robustness of data transmission. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0026] Figure 1 It is a structural schematic diagram of an existing base station;

[0027] Figure 2 is a schematic diagram of time slot allocation provided by an embodiment of the present invention;

[0028] Figure 3It is a schematic diagram of time slots corresponding to downlink services performed between a BBU and an RRU provided by an embodiment of the present invention;

[0029] Figure 4 is a schematic diagram of the structure of a base station provided by an embodiment of the present invention;

[0030] Figure 5 is a flowchart of a data transmission method between a BBU and an RRU provided in a first embodiment of the present invention;

[0031] Figure 6 is a schematic diagram of initial RE data provided by an embodiment of the present invention;

[0032] Figure 7 is a schematic diagram of comparison between a control signal and initial RE data provided by an embodiment of the present invention;

[0033] Figure 8 It is a schematic diagram of a process in which the RHUB compares the control signal with the cached RE data according to an embodiment of the present invention;

[0034] Fig. 9 is a flow chart of a data transmission method provided by an embodiment of the present invention;

[0035] Fig.10 is a structural diagram of a base station provided by a second embodiment of the present invention;

[0036] Fig.11 is a specific implementation flow chart of a data transmission method between a BBU and an RRU provided by another embodiment of the present invention;

[0037] Fig.12 It is a specific implementation flow chart of a data transmission method applied to uplink service between BBU and RRU provided by another embodiment of the present invention;

[0038] Fig.13 Schematic diagram of data writing and reading when performing uplink services provided by an embodiment of the present invention

[0039] Fig.14 It is a schematic diagram comparing the processing of uplink services and downlink services in a scenario of multi-stage cascaded RHUBs provided by an embodiment of the present invention;

[0040] Fig.15 It is a structural block diagram of a base station provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0042] For example, Figure 1 The structure diagram of the existing base station is shown. The base station can be used to transmit various types of mobile communication data, such as 3G mobile communication data, 4G mobile communication data and 5G mobile communication data. Figure 1 As shown, the base station includes at least the following three units, namely, an indoor baseband processing unit BBU, a radio frequency remote hub RHUB and a radio frequency remote unit RRU. Among them, the RHUB is configured on the transmission path between the BBU and the RRU, that is, one end of the RHUB is connected to one end of the BBU, and the other end of the RHUB is connected to the RRU. In this embodiment, the BBU is connected to two RRUs, namely RRU1 and RRU2. It should be noted that the number of RRUs connected to the BBU can be determined according to actual conditions. There can be one RRU connected to the BBU, or there can be two or more RRUs connected to the BBU. The number of RRUs connected to the BBU is not limited here. Among them, in the process of data transmission between the BBU and the RRU, it can be specifically divided into two types of services, namely, the downlink service of sending data from the BBU to the RRU, and the uplink service of sending data from the RRU to the BBU. The following takes the RE data transmission under the eCPRI protocol as an example. It should be noted that for RE data, for example, Figure 2As shown, a data frame corresponds to a cycle, and a cycle includes 10 time slots, namely, an uplink time slot U, a special time slot S, and a downlink time slot D. Each time slot can also be divided into multiple symbols. In this example, a time slot can be divided into 14 symbols, wherein the symbols in the uplink time slot U are all uplink symbols, the symbols in the downlink time slot D are all downlink symbols, and the special time slot S includes the uplink symbol U, the downlink symbol D, and the interval symbol G. It is easy to understand that the data corresponding to the uplink symbol (hereinafter referred to as "uplink symbol data") is used for uplink service transmission, and the data corresponding to the downlink symbol (hereinafter referred to as "downlink symbol data") is used for downlink service transmission. It should be understood that the number of time slots in the above-mentioned cycle and the number of symbols in a time slot can be set according to the clock frequency; the ratio of the uplink time slot U, the special time slot S, and the downlink time slot D in a cycle, and the ratio of the uplink symbol U, the downlink symbol D, and the interval symbol G in a special time slot can be set according to actual needs. The number of cycles (frames) in data (or signals), the number or type of time slots contained in a cycle, the number of symbols in a time slot, and the ratio of each type of symbol in a special time slot can be collectively referred to as the time slot ratio of data (or signals). During the uplink and downlink services between BBU and RRU, the agreed time slot ratio can be used for data transmission.

[0043] In the process of executing downlink services, the BBU encapsulates the RE data to be sent into multiple data frames, compresses them, obtains the RE data to be sent encapsulated based on the eCPRI protocol, and sends them to the RHUB. The RHUB receives the RE data through the receiving module, decompresses the RE data to be sent in the decompression module, performs IFFT processing on the decompressed data block in the IFFT module, and stores the processed RE data in the cache area in the cache module, that is, the cached RE data is obtained. The RHUB can read the RE data from the cache area, and after inserting the CP in the CP insertion module, distribute it to the corresponding RRU for sending. Since it takes a certain amount of time to perform the above-mentioned processing, in order to achieve delay alignment between each unit, a preset delay compensation duration can be set between the BBU and the RRU. The BBU sends the data to the RHUB in advance for processing. The length of the advance time is the above-mentioned delay compensation duration.

[0044] For example, Figure 3 The following is a schematic diagram showing the time slots corresponding to the downlink service between the BBU and the RRU provided in one embodiment of the present application. Figure 3As shown, the preset delay compensation duration between BBU and RRU is 4 time slots. If BBU needs to send Data1 in the first downlink time slot (i.e., time slot 6) of the 2T transmission cycle, the data will be sent to RHUB 4 time slots in advance for processing and storage, that is, RHUB will receive Data1 sent by BBU in the last downlink time slot (i.e., time slot 1) of the previous cycle, and process Data1. The processing process can be found in the above description and will not be repeated here. RHUB will store the processed data in the cache area, that is, obtain the pre-stored data. In the first downlink time slot (i.e., time slot 6) of the 2T cycle, RHUB can send the pre-stored data stored in the cache area to RRU, thereby realizing the delay alignment between BBU and RRU. Subsequent data can also be completed in accordance with the above method, and Data2 to Data4 are sent to RHUB in the time slots corresponding to the preset delay compensation duration in sequence.

[0045] However, in the actual transmission process, the BBU may send Data1 to the RHUB a certain time in advance, but the RHUB may not receive the Data1 in the first downlink time slot (i.e., time slot 6) of the 2T cycle, and may receive Data1 in the second downlink time slot (i.e., time slot 7) due to the fact that the transmission link has just been established or the processing capacity is insufficient, or the delay fluctuates. The existing data transmission method will send Data1 in the second downlink time slot (i.e., time slot 7), and delay the transmission of subsequent data in sequence, which leads to the delay misalignment between the BBU and the RRU, reducing the robustness and accuracy of the data transmission process.

[0046] In order to solve the problems in the prior art, Figure 4 A schematic diagram of the structure of a base station provided by another embodiment of the present application is shown. In this embodiment, the RHUB is configured with a control module, and a control signal is outputted by the control module to keep the delay alignment between the BBU and the RHUB when transmitting downlink services.

[0047] In the embodiment of the present invention, the execution subject of the process is a data transmission system between a BBU and an RRU. The data transmission system may specifically be a base station, which includes at least one BBU, at least one RHUB, and at least one RRU. Figure 5 The following is a flowchart of a method for transmitting downlink data in accordance with the first embodiment of the present invention, which is described in detail as follows:

[0048] In S501, the radio remote hub RHUB receives RE data sent by the baseband processing unit BBU, and caches the RE data, wherein the RE data carries a symbol number.

[0049] In this embodiment, the BBU sends RE data to the RHUB when executing downlink services. The RE data carries a number. The number includes a cycle number, a time slot number, and a symbol number. The numbering method of these three numbers is performed according to the time slot ratio. One embodiment of the numbering method is to perform from 1 to n according to the time slot or symbol type. Figure 6 As shown, it is the data structure of the initial RE data generated by the BBU. The cycle number 1T represents the first cycle, the time slot number 1T1D represents the first downlink time slot of the first cycle, and the symbol number 1T1D1d represents the first downlink symbol of the first downlink time slot of the first cycle, and so on. nTnDnD represents the Nth downlink symbol of the Nth downlink time slot of the Nth cycle. It should be noted that the length of an RE data can be one cycle or multiple cycle lengths. It is easy to understand that since only downlink symbols are sent in the downlink service, the RE data sent by the BBU and the cached RE data do not include the above-mentioned G and U symbols.

[0050] In S502, the RHUB generates a control signal synchronously with the BBU sending the RE data, and the control signal has the same number as the initial RE data corresponding to the sent RE data.

[0051] In this embodiment, when the RHUB executes the downlink service, a control signal may be generated through a built-in control module, and the control signal has the same number as the initial RE data. It should be noted that the same number as the control signal means that the time slot ratio and numbering method are the same. The initial RE data corresponding to the sent RE data may be referred to as the initial data of the sent RE data. For example, Figure 7 FIG. 1 is a schematic diagram showing a control signal provided by an embodiment of the present application. Figure 6 As shown, the control signal has the same time slot ratio as the initial RE data, that is, the signal length is one cycle, and one cycle T contains 10 time slots, namely 7 downlink time slots D, 1 special time slot S and 2 uplink time slots U, wherein each time slot contains 14 symbols, and for special time slots, it contains 6 downlink symbols d, 4 interval symbols g and 4 uplink symbols u, and each symbol can carry corresponding symbol data, namely Data. Among them, the above-mentioned cycles, time slots and symbols are all numbered, and the numbering method of the two is the same. It is easy to understand that when the symbol numbers of the two are the same, the corresponding cycle and time slot numbers are also the same. Therefore, the same numbering means the same symbol numbering.

[0052] It should be noted that, in the process of executing downlink services, the control signal can be generated at a certain rate, and the rate is the same as the data transmission rate of the BBU, that is, the sending of RE data by the BBU and the generation of control signals by the control module are executed synchronously. The synchronization means that in order to achieve delay alignment, the BBU will send RE data to the RHUB in advance for a preset delay compensation duration.

[0053] In S503, the RHUB controls the reading of the buffered RE data based on the comparison between the control signal and the symbol number of the RE data, and sends the read RE data to the remote radio unit RRU to align the delays.

[0054] During data transmission, the RHUB compares the coding of the control signal generated by the control module with the symbol number of the RE data stored in the cache area. Based on the comparison result, the RHUB can control the reading of the cached RE data and send the read RE data to the radio remote unit RRU to align the delay.

[0055] In a possible implementation manner, if the RHUB is connected to two or more RRUs, the read RE data may be distributed to the corresponding RRUs for transmission.

[0056] like Figure 8 The figure shows a process diagram of RHUB comparing the control signal with the cached RE data. It should be noted that in downlink service processing, BBU only sends downlink symbol data to RHUB; similarly, in uplink service processing, RRU only sends uplink symbol data to RHUB. Specifically, S503 can be divided into the following two cases:

[0057] Case 1: If the control signal is consistent with the symbol number of the cached RE data, the RHUB reads the cached RE data corresponding to the consistent symbol number, and sends the RE data corresponding to the consistent symbol number to the RRU.

[0058] The symbol number consistency means that the symbol numbers of the control signal and the RE data are the same at the same time. It is easy to understand that, in fact, when the symbol numbers are the same, the corresponding cycle and time slot numbers are also the same. At this time, the cached RE data corresponding to the same symbol number can be read, and the read RE is sent to the RRU.

[0059] Case 2: If the symbol numbers of the control signal and the RE data are inconsistent, the RHUB sends the agreed data to the RRU.

[0060] It is easy to understand that if the two do not match, it means that there is a delay misalignment. At this time, the corresponding operation will be performed to repair the above situation and maintain the delay alignment between each unit during the entire transmission process.

[0061] In this embodiment, if the RHUB identifies that the symbol number of the RE data in the cache area is inconsistent with the symbol number of the control signal, the inconsistent symbol number means that the symbol numbers of the control signal and the RE data are different at the same time, that is, one or more inconsistencies exist in the cycle number, the time slot number and the symbol number, which indicates that the delay between the BBU and the RHUB is not aligned. The reason for the delay misalignment may be that the data sent by the BBU arrives late or is still undergoing related preprocessing in the RHUB, resulting in the delay misalignment between the BBU and the RHUB. In this case, the RHUB will not send RE data with inconsistent numbers, but will send preset agreed data to the RRU.

[0062] The situation of inconsistent symbol numbers can be divided into two cases:

[0063] Case 2.1: During the downlink symbol period of the control signal, the RHUB sends the scheduled data to the RRU.

[0064] Case 2.2: If, during the interval symbol or uplink period of the control signal, the RHUB sends the agreed data to the RRU and determines whether RE data is stored in the cache area; if RE data is stored in the cache area, the RHUB performs a response operation based on comparing the RE data with the symbol number of the next downlink symbol.

[0065] In this embodiment, when the RHUB detects that the control signal is during the uplink symbol or the interval symbol, it indicates that it is not a downlink service transmission. Under normal circumstances, it will not receive the RE data sent by the BBU, that is, the buffer area will not write the RE data. In this case, the RHUB can send the preset agreed data to the RRU.

[0066] During the uplink symbol or interval symbol of the control signal, the number of the next downlink symbol of the control signal is compared with the symbol number of the RE data, and a corresponding operation is performed according to the comparison result.

[0067] The comparison results can be specifically divided into two categories. The first category is that the symbol number of the RE data is consistent with the symbol number of the next downlink symbol; the second category is that the RE data is inconsistent with the symbol number of the next downlink symbol.

[0068] In the case of consistency, the RHUB may read the RE data corresponding to the consistent symbol number in the next downlink symbol, and send the RE data corresponding to the consistent symbol number to the RRU.

[0069] Inconsistency indicates data anomaly, which is divided into two types: late data anomaly and data error anomaly (sending empty data or data inconsistent with the symbol number will be considered as error data). Figure 8 At this time, an error number clear enable is generated to delete the RE data of the inconsistent symbol number.

[0070] Exemplarily, after the above steps, the data transmission method in this embodiment further includes continuous inconsistent downlink symbol detection. During the downlink symbol period of the control signal, when the RHUB detects that the number of symbols that are continuously inconsistent between the RE data and the control signal exceeds a threshold, it indicates that the delay difference at this time is large. At this time, the RHUB will stop reading the cached RE data, and re-agree with the RRU on the preset delay compensation duration, and re-perform the above steps S501-S503. Among them, the threshold can be preset according to actual needs.

[0071] For example, Fig. 9 FIG. 1 is a flow chart showing a data transmission method provided by an embodiment of the present application. Fig. 9 As shown, the downlink data transmission method specifically includes the following steps:

[0072] Step 1: In the process of performing downlink services, the RHUB generates a control signal having the same number as the initial RE data in the BBU.

[0073] Step 2: RHUB determines whether the control signal is in the downlink symbol. If yes, it goes to step 3; if no, it goes to step 7.

[0074] Step 3: The RHUB obtains the ID of the RE data in the cache area.

[0075] Step 4: Determine whether the serial numbers of the RE data and the control signal are consistent. If yes, go to step 5; if no, go to step 6.

[0076] Step 5: Read the RE data corresponding to the consistent symbol number, and send the RE data corresponding to the consistent symbol number to the RRU.

[0077] Step 6: Do not read the RE data corresponding to the inconsistent symbol numbers, and send the preset agreed data to the RRU.

[0078] Step 7: If the control signal is in the uplink symbol and the interval symbol period, the RHUB sends the preset agreed data to the RRU.

[0079] Step 8: If the RHUB detects that there is RE data in the cache area, it reads the number of the RE data.

[0080] Step 9: Determine whether the symbol number of the RE data is consistent with the symbol number of the next downlink symbol. If so, wait for the next downlink symbol to arrive, return to step 1, and during the next downlink symbol, read the RE data corresponding to the consistent symbol number, and send the RE data corresponding to the consistent symbol number to the RRU; if not, execute step 10.

[0081] Step 10: Delete the RE data corresponding to the inconsistent symbol numbers in the cache area.

[0082] In the process of executing uplink services, the RRU can cache the uplink service data in the RHUB, remove the CP in the uplink service data, and perform the inverse processing corresponding to the downlink service, that is, after FFT (fast Fourier transform), compression and sending the inversely processed data to the BBU for decompression to complete the uplink service. Among them, if there are two RRUs connected to the RHUB, the uplink service data of the two-level RRUs can be cached at the first level in the RHUB and aligned in the time domain. The data is generated according to the data frame header of the accompanying channel, and a write address trigger signal is generated. In response to the write address trigger signal, the RHUB will write the uplink service data into the cache area, and the read side uses a unified read address to read the data, thereby realizing data alignment. Then the CP removal operation is performed in the CP removal module.

[0083] From the above, it can be seen that in the embodiment of the present invention, a data transmission method applied between BBU and RRU is provided. In the process of executing the downlink data service from BBU to RRU, the RE data sent by BBU to RHUB will carry a symbol number. When RHUB receives the RE data sent by BBU, it will also generate a control signal synchronously with the RE data sent by BBU, and the control signal has the same symbol number as the RE data. RHUB identifies whether the delay between BBU and RHUB is aligned by comparing whether the symbol numbers of RE data and control signal are consistent, and controls the reading of cached RE data based on the delay alignment, and sends the read RE data to the radio remote unit RRU to align the delay, which solves the problem of delay misalignment in the existing transmission between BBU and RRU and improves the accuracy and robustness of data transmission.

[0084] Fig.10 FIG. 2 shows a schematic diagram of the structure of a base station provided by the second embodiment of the present invention. Fig.10 As shown, the base station includes a BBU and at least two RHUBs, each of which is connected to two RRUs, wherein the two RHUBs are RUB1 and RHUB2, that is, there are two RHUBs cascaded between the BBU and the RRU in the distributed benchmark. Of course, in other scenarios, more than two RHUBs can be cascaded. Figure 8 As shown, RHUB2 in the figure is the RHUB connected to RHUB1, and correspondingly, RHUB1 is the RHUB connected to RHUB2. Of course, in other scenarios, RHUB2 can also be connected to RHUB3, and so on. The operation process performed by each unit can refer to the description of the previous embodiment, and will not be repeated here.

[0085] Fig.11 FIG. 2 shows a specific implementation flow chart of a downlink data transmission method provided by another embodiment of the present application. Fig.11 A downlink data transmission method provided in this embodiment is used in a base station of multiple RHUB cascades. The downlink data transmission method specifically includes: S1101 to S1105, which are described in detail as follows:

[0086] In S1101, RHUB1 receives RE data sent by the BBU; wherein the RE data carries a number.

[0087] In S1102, RHUB1 forwards the RE data sent by the BBU to the RHUB connected to RHUB1, that is, to RHUB2.

[0088] In this embodiment, if there are multiple cascaded RHUBs in the base station, the upstream RHUB will forward the data received from the BBU to the cascaded RHUBs. Fig.10 As shown in the figure, RHUB1 is the first-level RHUB connected to the BBU, and the BBU will send the required downlink data to RHUB1; and RHUB2 is the downstream RHUB of RHUB1, so RHUB1 will forward the received RE data to the downstream RHUB, that is, RHUB2. If RHUB2 is also connected to another RHUB, such as RHUB3, then the RE data received by the upstream RHUB can be forwarded to the downstream RHUB, that is, the downlink data received by RHUB1 is forwarded to RHUB3, and so on.

[0089] In S1103, RHUB1 preprocesses the RE data and stores the preprocessed RE data in a cache area; meanwhile, RHUB2 preprocesses the RE data and stores the preprocessed RE data in a cache area of ​​RHUB2.

[0090] In S1104, RHUB1 generates a control signal synchronized with the RE data sent by the BBU; the control signal has the same symbol number as the RE data. At the same time, RHUB2 generates a control signal synchronized with the RE data sent by the BBU.

[0091] In S1105, RUB1 controls the reading of cached RE data based on the comparison between the local control signal and the symbol number of the RE data, and sends the read RE data to the RRU connected to RUB1 to align the delay. At the same time, RHUB2 controls the reading of cached RE data based on the comparison between the local control signal and the symbol number of the RE data, and sends the read RE data to the RRU connected to RHUB2 to align the delay.

[0092] In the subsequent process of executing the downlink service, the processing is similar to that of a single RHUB, and the specific description can refer to the relevant description of the previous embodiment, which will not be repeated here.

[0093] In the embodiment of the present application, in the case of multi-level cascaded RHUBs, the upper-level RHUB will forward the corresponding data to the lower-level RHUB and perform latency alignment operations at each level of RHUB, thereby improving the accuracy and robustness of the data transmission process in the scenario of multi-level RHUB cascade.

[0094] Fig.12 FIG. 2 shows a specific implementation flow chart of an uplink data transmission method provided by another embodiment of the present invention. Fig.12 The base station provided in this embodiment includes a multi-stage cascaded RHUB, and the uplink data transmission method includes: S1201 to S1209, which are described in detail as follows:

[0095] In S1201, when executing the uplink service, RHUB1 detects whether the first uplink data sent by the RRU is stored in the local cache area; the first uplink data carries a number; illustratively, the number is consistent with the numbering method of the numbering in the downlink data transmission process. For details, please refer to the above description and will not be repeated here.

[0096] In S1202, if RHUB1 does not detect that the local buffer area stores the first uplink data sent by the RRU, that is, the buffer area is empty, it returns to execute the operation of S1001.

[0097] In this embodiment, the monitoring process can determine whether the first uplink data is written into the local cache area by generating a corresponding write instruction in the cache area.

[0098] For example, Fig.13 A schematic diagram showing data writing and reading when performing uplink services provided by an embodiment of the present application is shown. Fig.13As shown in the figure, the RRU will write uplink data to the corresponding RHUB, where the RRU connected to RHUB1 writes the first uplink data; and the RRU connected to the secondary RHUB2 writes the second uplink data. Similar to the downlink data, the uplink data will be transmitted in the uplink symbols of the uplink time slot and the special time slot, as shown in the write side sequence. Correspondingly, the writing sequence of RHUB2 is the same as that of RHUB1, which will not be repeated here.

[0099] In S1203, if it is detected that the first uplink data sent by the RRU to BBU1 is stored in the buffer area, RUB1 starts a waiting window and monitors whether the second uplink data sent by RHUB2 is received.

[0100] In this embodiment, in order to achieve delay alignment, when the RRU sends uplink data to the BBU, RHUB1 needs to configure a waiting window to send the RE data of the uplink service to the BBU within a preset waiting time. The waiting window is related to the uplink window of the BBU.

[0101] In other scenarios, if RHUB2 is connected to a RHUB such as RHUB3, RHUB2 may also start a local waiting window when receiving the second uplink data sent by the RRU connected to it. In this case, the waiting window of RHUB2 is related to the number of cascade layers of RHUB2 in the multi-stage cascaded RHUBs.

[0102] For multi-level cascaded RHUBs, RHUB needs to store the data after FFT is completed at this level in the local first cache area. The first cache area is specifically used to store the symbol data after FFT processing is completed by the RHUB at this level. For example, for RHUB1, the first uplink data is stored in the first cache area. The RHUB1 is also configured with another cache area, which is the second cache area, for storing the symbol data after FFT processing sent by the downstream RHUB. For example, for RHUB1, the second cache area is specifically used to store the second uplink data. If the cascade level of the RHUB is lower, that is, the number of upstream RHUBs is greater, the more merging operations need to be performed subsequently, so the waiting window should be set smaller to reserve enough time for the subsequent merging operations; conversely, the higher the cascade level of the RHUB is, that is, the fewer the number of upstream RHUBs is, the larger the waiting window is, but the maximum value of the waiting window will not exceed the uplink window of the BBU. By configuring corresponding waiting windows for different levels, processing timeouts can be identified in a timely manner to avoid the impact of lower-level processing timeouts on the upper-level RHUB, thereby improving the accuracy of data transmission and the timeliness of exception identification.

[0103] In S1204, RHUB1 determines whether the waiting window is exceeded. If so, the operation of S1210 is performed; if not, it determines whether the second uplink data sent by the downstream RHUB2 is received.

[0104] In S1205, if the second uplink data sent by the secondary RHUB is not received, the process returns to execute the operation of S1204.

[0105] In S1206, if RHUB1 receives the second uplink data uploaded by the RHUB connected to RHUB1 (i.e., RHUB2) within the waiting window, RHUB1 obtains the number of the second uplink data. Similarly, the second uplink data uploaded by RHUB2 also carries a number, and the numbering method of the number is the same as that described in the above embodiment, which will not be repeated here.

[0106] In S1207, it is determined whether the serial number of the first uplink data is consistent with the serial number of the second uplink data. If they are consistent, the operation of S1208 is executed; otherwise, the operation of S1209 is executed.

[0107] In S1208, if the symbol numbers of the first uplink data and the second uplink data are consistent, RHUB1 combines the first uplink data and the second uplink data corresponding to the consistent symbol numbers, and sends the combined data of the first uplink data and the second uplink data to the BBU.

[0108] In this embodiment, RHUB1 combines the first uplink data with the second uplink data and sends the combined data to the BBU. Of course, if RHUB1 has an upstream RHUB, the combined data can be sent to the upstream RHUB.

[0109] Exemplarily, the merging method is cell merging, wherein the method for performing cell merging is specifically: merging the data with the same symbol number in the first uplink data and the second uplink data, for example, merging the data of 1T1U1u in the first uplink data with the data of 1T1U1u in the second uplink data, merging the data of 1T1U2u in the first uplink data with the data of 1T1U2u in the second uplink data, and so on, completing the merging of all data in the first uplink data and the second uplink data. In the case where there are multiple levels of cascaded RHUBs in the base station, each level of RHUB will generate a control signal according to the synchronized control module, and will remove the CP and process the received uplink data locally at each level of RHUB and insert the number. At this time, if the delay alignment of multiple levels of RHUB and BBU is to be achieved, it is necessary to perform cell merging on the uplink data received from other levels of RHUBs at the first level RHUB, and then transmit the merged data back to the BBU. This requires that the upper-level RHUB has the cache capability to store data uploaded by the secondary RHUB. For example, RHUB1 needs to have the capability to store cache data uploaded by RHUB2, and the first uplink data of RHUB1 needs to wait for RHUB2 to upload the second uplink data with the same data number before merging and sending it to the BBU.

[0110] In S1209, if the symbol numbers of the first uplink data and the second uplink data are inconsistent, RUB1 deletes the second uplink data corresponding to the inconsistent symbol numbers, and sends the first uplink data corresponding to the inconsistent symbol numbers to the BBU.

[0111] In this embodiment, if RHUB1 recognizes that the symbol numbers of the first uplink data and the second uplink data are inconsistent, RHUB1 will delete the second uplink data corresponding to the inconsistent symbol numbers and send the first uplink data corresponding to the inconsistent symbol numbers to the BBU. As described above, the second uplink data will be stored in the second cache area, and the BBU will delete the second uplink data with the inconsistent symbol numbers in the second cache area.

[0112] In S1210, if the second data uploaded by RHUB2 is not received within the waiting window, the first uplink data is sent to the BBU.

[0113] In this embodiment, since the hardware processing time of different RHUBs is basically fixed, as long as the waiting window is set reasonably, theoretically the data of the upper RHUB will arrive within the waiting threshold. If the data does not arrive within the waiting window, it means the waiting timeout, and only the uplink data of the current RHUB is sent (that is, for RHUB1, it is the first uplink data).

[0114] In an embodiment of the present application, in a base station with multiple levels of cascaded RHUBs, in the process of executing uplink services, uplink data can be merged and latency aligned in the cache areas of the RHUBs at each level, and corresponding waiting windows can be configured for the RHUBs corresponding to different levels, so that abnormal situations of processing timeout and consistent symbol numbers can be identified in time, thereby improving the accuracy and robustness of data transmission.

[0115] For example, Fig.14 FIG. 1 is a schematic diagram showing a comparison of the processing of uplink services and downlink services in a scenario of multi-stage cascaded RHUBs provided by an embodiment of the present application. Fig.14 As shown in the figure, in the process of executing the downlink service, the RHUBs at all levels are synchronized with the BBU. After the synchronization is completed, the BBU will send the RE data of the downlink service to the top RHUB, that is, send the RE data of the downlink service to RHUB1. RHUB1 will send the received RE data of the downlink service to its subordinate secondary RHUB, that is, RHUB2 receives the RE data of the downlink service sent by RHUB1. If RHUB2 has a subordinate RHUB, it will continue to forward the RE data of the downlink service. After receiving the RE data of the downlink service, RHUB1 and RHUB2 can process the RE data and send the RE data of the downlink service to the connected RRU at the same time in the corresponding time slot.

[0116] In the process of executing uplink services, each level of RHUB will receive uplink service data sent by the connected RRU, and then the upper RHUB will wait for the uplink service data uploaded by the secondary RHUB, such as RHUB1 waiting for the uplink service data uploaded by RHUB2, and start the waiting window. If the uplink data uploaded by the secondary RHUB is received within the waiting window, the uplink data of this level will be merged with the uplink data uploaded by the secondary to obtain the merged uplink data, and the merged uplink data will be sent to the BBU.

[0117] It should be understood that the order of execution of the steps in the above embodiment does not necessarily mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present invention.

[0118] Fig.15 The structure block diagram of a base station provided by an embodiment of the present invention is shown. The base station includes units for executing Figure 5 , Fig.11 as well as Fig.12 For details, please refer to the steps in the corresponding embodiment. Figure 5 , Fig.11 as well as Fig.12 For the convenience of explanation, only the parts related to this embodiment are shown.

[0119] See also Fig.15 , a base station, the base station comprising at least one BBU 131, at least one RHUB 152 and at least one RRU 153;

[0120] The RHUB 152 is used to receive RE data sent by the BBU 151 and cache the RE data during the execution of the downlink service, wherein the RE data carries a symbol number;

[0121] The RHUB 152 is used to generate a control signal synchronously with the RE data sent down by the BBU 152, and the control signal has the same symbol number as the RE data;

[0122] The RUHB 152 is used to control the reading of the cached RE data based on the comparison between the control signal and the symbol number of the RE data, and send the read RE data to the RRU 153 to align the delay.

[0123] Optionally, the RHUB 152 is configured to control the reading of the cached RE data based on the comparison between the control signal and the symbol number of the RE data, and send the read RE data to the RRU 153, including:

[0124] The RHUB 152 is configured to read the RE data corresponding to the consistent symbol number in the cache if the control signal is consistent with the symbol number of the RE data, and send the RE data corresponding to the consistent symbol number to the RRU;

[0125] The RHUB 152 is configured to send the agreed data to the RRU if the symbol numbers of the control signal and the RE data are inconsistent.

[0126] Optionally, the RHUB 152 is configured to send the agreed data to the RRU if the symbol number of the control signal is inconsistent with the symbol number of the RE data, including:

[0127] The RHUB152 is used to send the agreed data to the RRU during the interval symbol or uplink symbol of the control signal, and determine whether RE data is stored in the buffer area;

[0128] The RHUB 152 is configured to perform a response operation based on a comparison between the RE data and a symbol number of a next downlink symbol if RE data is stored in the buffer area.

[0129] Optionally, the RHUB 152 is configured to perform a response operation based on a comparison between the RE data and a symbol number of a next downlink symbol if RE data is stored in the buffer area, including:

[0130] The RHUB152 is configured to read the RE data corresponding to the consistent symbol number in the next downlink symbol if the RE data is consistent with the symbol number of the next downlink symbol, and send the RE data corresponding to the consistent symbol number to the RRU;

[0131] The RHUB 152 is used to generate a clear enable if the RE data is inconsistent with the symbol number of the next downlink symbol, so as to delete the RE data corresponding to the inconsistent symbol number in the cache area.

[0132] Optionally, the BBU 151 in the base station is connected to RHUB 152 and RHUB 154; wherein RHUB 152 is the upper connected RHUB of RHUB 154;

[0133] The RHUB 152 is configured to start a waiting window if the cached first uplink data sent by the RRU 153 is detected during the execution of the uplink service;

[0134] The RHUB152 is used to control the merging of the first uplink data and the second uplink data based on whether the second uplink data uploaded by the RHUB154 is received within the waiting window, and send the first uplink data or the data combined with the first uplink data and the second uplink data to the BBU to align the delay.

[0135] Optionally, the first RHUB 152 controls the merging of the first uplink data and the second uplink data based on whether the second uplink data uploaded by the RHUB 154 is received within the waiting window, and sends the first uplink data or data combined with the first uplink data and the second uplink data to the BBU to align the delays, including:

[0136] The RHUB152 is configured to determine whether the symbol numbers of the first uplink data and the second uplink data are consistent if the second uplink data uploaded by the RHUB154 is received within the waiting window;

[0137] The RHUB1532 is configured to combine the first uplink data and the second uplink data corresponding to the consistent symbol numbers if the symbol numbers of the first uplink data and the second uplink data are consistent, and send the combined data of the first uplink data and the second uplink data to the BBU151;

[0138] The RHUB1532 is configured to delete the second uplink data corresponding to the inconsistent symbol numbers if the symbol numbers of the first uplink data and the second uplink data are inconsistent, and send the first uplink data corresponding to the inconsistent symbol numbers to the BBU.

[0139] Optionally, the merging of the first uplink data and the second uplink data corresponding to the consistent symbol number is specifically: performing cell merging of the first uplink data and the second uplink data corresponding to the consistent symbol number.

[0140] Optionally, the RHUB 152 is configured to control the merging of the first uplink data and the second uplink data based on whether the second uplink data uploaded by the RHUB 154 is received within the waiting window, and send the first uplink data or data combined with the first uplink data and the second uplink data to the BBU to align the delays, including:

[0141] The RHUB 152 is configured to send the first uplink data to the BBU if the first RHUB does not receive the second uplink data uploaded by the RHUB 154 within the waiting window.

[0142] Therefore, the base station provided in the embodiment of the present invention can also carry a symbol number in the process of executing the downlink service of sending data from BBU to RRU. When RHUB receives the RE data sent by BBU, it will also generate a control signal synchronously with the RE data sent by BBU, and the control signal has the same symbol number as the RE data. RHUB identifies whether the delay between BBU and RHUB is aligned by comparing whether the symbol numbers of RE data and control signal are consistent, and controls the reading of cached RE data based on the delay alignment, and sends the read RE data to the radio remote unit RRU to align the delay, which solves the problem of delay misalignment in the existing transmission between BBU and RRU and improves the accuracy and robustness of data transmission.

[0143] The base station includes a distributed base station and an integrated base station. A distributed base station is a base station that uses the above-mentioned BBU, RRU, and RHUB as independent devices, which is common in macro base stations. An integrated base station usually assembles or integrates the above-mentioned BBU, RRU, and RHUB into the same device, which is common in micro base stations.

[0144] The embodiment of the present invention further provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps in the above-mentioned various method embodiments can be implemented. The computer-readable storage medium can be non-volatile or volatile. The computer-readable storage medium includes: a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and other media that can store program codes.

[0145] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0146] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. A downlink data transmission method, characterized in that: include: The radio remote hub RHUB receives frequency domain resource RE data sent by the baseband processing unit BBU, and caches the RE data, wherein the RE data carries a symbol number; The RHUB generates a control signal synchronously with the BBU sending the RE data, and the control signal has the same symbol number as the initial data of the RE data; The RHUB controls the reading of the buffered RE data based on the comparison between the control signal and the symbol number of the RE data, and sends the read RE data to the remote radio unit RRU to align the delays.

2. The downlink data transmission method according to claim 1, characterized in that: The RHUB controls the reading of the cached RE data based on the comparison between the control signal and the symbol number of the RE data, and sends the read RE data to the remote radio unit RRU, including: If the control signal is consistent with the symbol number of the RE data, the RHUB reads the RE data corresponding to the consistent symbol number from the cache, and sends the RE data corresponding to the consistent symbol number to the RRU; If the symbol numbers of the control signal and the RE data are inconsistent, the RHUB sends the agreed data to the RRU.

3. The downlink data transmission method according to claim 2, characterized in that: If the symbol number of the control signal is inconsistent with the symbol number of the RE data, the RHUB sends the agreed data to the RRU, including: If it is during the interval symbol or uplink symbol of the control signal, the RHUB sends the agreed data to the RRU and determines whether RE data is stored in the buffer area; If the RE data is stored in the buffer area, the RHUB performs a response operation based on comparing the RE data with the symbol number of the next downlink symbol.

4. The downlink data transmission method according to claim 3, characterized in that: If the RE data is stored in the buffer area, the RHUB performs a response operation based on comparing the RE data with the symbol number of the next downlink symbol, including: If the RE data is consistent with the symbol number of the next downlink symbol in the control signal, the RHUB reads the RE data corresponding to the consistent symbol number in the next downlink symbol, and sends the RE data corresponding to the consistent symbol number to the RRU; If the RE data is inconsistent with the symbol number of the next downlink symbol in the control signal, the RHUB generates a clear enable to delete the RE data corresponding to the inconsistent symbol number in the cache area.

5. The downlink data transmission method according to any one of claims 1 to 4, characterized in that: After the RHUB controls the reading of cached RE data based on the comparison of the control signal and the symbol number of the RE data, and sends the read RE data to the radio remote unit RRU, the method includes: detecting the number of consecutive inconsistent symbols during the downlink symbol period of the control signal, and repeating the steps of the downlink data transmission method when it is detected that the number of symbols exceeds a threshold.

6. A radio remote hub RHUB, characterized in that: include: A receiving module is used to receive RE data sent by a baseband processing unit BBU; A cache module, used for caching the RE data, wherein the RE data carries a symbol number; A control module, configured to generate a control signal synchronously with the RE data sent by the BBU, wherein the control signal has the same symbol number as the initial data of the RE data; the control module is further configured to control the reading of the RE data based on a comparison between the control signal and the symbol number of the RE data; The sending module is used to send the read RE data to the radio remote unit RRU to align the delay.

7. The radio remote hub RHUB according to claim 6, characterized in that: Also includes: The CP inserting module is used to insert a cyclic prefix CP into the read RE data.

8. A base station, characterized in that: The base station comprises: at least one indoor baseband processing unit BBU, at least one radio remote hub RHUB as claimed in any one of claims 6-7, and at least one radio remote unit RRU.

9. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the method according to any one of claims 1 to 5 is implemented.

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