A method and apparatus for measuring a two-way connection dual fiber delay

Abstract

The application discloses a method and device for measuring time delay of two-way connection double optical fiber. The method is applied to a first baseband unit, and signals are transmitted between the first baseband unit, a radio frequency unit and a second baseband unit through the double optical fiber, and comprises the following steps: a time delay measurement handshake request is sent to the second baseband unit; a first response information of the second baseband unit to the time delay measurement handshake request is received, and the first response information comprises a time delay difference of a transmitting end and a receiving end of an optical port of the second baseband unit; a time delay measurement request is sent to the radio frequency unit, and a second response information of the radio frequency unit to the time delay measurement request is received; and based on the time delay difference in the first response information, the second response information and a preset rule, time delay differences of the double optical fiber from the first baseband unit to the radio frequency unit and from the second baseband unit to the radio frequency unit are determined.

Description

Technical Field

[0001] This invention relates to the field of communication technology, and in particular to a method and apparatus for measuring the delay of a bidirectional connection with two optical fibers. Background Technology

[0002] Currently, for high-reliability wireless communication ring network scenarios, fiber optic redundancy is implemented. That is, a radio element (RE) can be connected to one or two baseband units (BBU) through two optical fibers. This ensures that when one optical fiber fails, the corresponding radio element can still function normally.

[0003] Currently, when measuring fiber optic delay in scenarios where the baseband unit and radio frequency (RF) unit are directly connected, a unidirectional fiber optic delay measurement scheme using the RF unit is generally employed. This indicates that the delay measurement methods in these technologies rely on frame header alignment at the transmitting and receiving ends. In misaligned scenarios, only unidirectional delay can be measured separately; two delay measurement processes are required to measure the bidirectional fiber optic delay. For example, when measuring fiber optic delay in the aforementioned ring network scenario, only unidirectional delay can be measured separately; that is, two delay measurement processes are required to measure the bidirectional fiber optic delay.

[0004] As can be seen, in the relevant technologies for measuring fiber delay in ring network scenarios, only the fiber delay of one fiber can be measured at a time. Therefore, the solution is to measure the fiber delay of one fiber first. When it is necessary to switch between two fibers, the fiber delay of the other fiber is measured, which means that the delay measurement needs to be done again, increasing the fiber switching time. Summary of the Invention

[0005] This invention provides a method and apparatus for measuring the delay of two optical fibers in a bidirectional connection, which provides a scheme for measuring the delay of two optical fibers at one time, reducing the fiber switching time.

[0006] The specific technical solutions provided by the embodiments of the present invention are as follows:

[0007] In a first aspect, embodiments of the present invention provide a method for measuring the delay of a bidirectional connection using two optical fibers, applied to a first baseband unit, wherein the first baseband unit, a radio frequency unit, and a second baseband unit transmit signals through the two optical fibers, the method comprising:

[0008] Send a delay measurement handshake request to the second baseband unit;

[0009] The system receives a first response message from the second baseband unit in response to the delay measurement handshake request. The first response message includes the delay difference between the optical port transmitter and receiver measured by the second baseband unit.

[0010] Send a delay measurement request to the radio frequency unit and receive a second response from the radio frequency unit to the delay measurement request;

[0011] Based on the time delay difference in the first response information, the second response information, and the preset rules, the time delay difference from the first baseband unit to the radio frequency unit and the time delay difference from the second baseband unit to the radio frequency unit of each of the two optical fibers are determined.

[0012] In one possible implementation, if the radio frequency unit includes only one radio frequency unit, and the synchronization signals of the first baseband unit and the second baseband unit are aligned, then the preset rule is:

[0013] Based on the transmit / receive delay difference within the first optical port in the second response message and the delay difference between the transmitter and receiver of the measurement optical port of the first baseband unit, a first delay difference is determined; wherein, the first optical port is the optical port of the radio frequency unit closer to the first baseband unit; the first delay difference is the delay difference from the first baseband unit to the radio frequency unit corresponding to the dual optical fibers;

[0014] Based on the transmit / receive delay difference in the second optical port in the second response message and the delay difference in the first response message, a second delay difference is determined; wherein, the second optical port is the optical port of the radio frequency unit closer to the second baseband unit; the second delay difference is the delay difference from the second baseband unit to the radio frequency unit corresponding to the dual optical fibers.

[0015] In one possible implementation, if the radio frequency unit includes only one radio frequency unit, and the synchronization signals of the first baseband unit and the second baseband unit are not aligned, and the period of the synchronization signal transmitted by the transmitter of the first baseband unit is much greater than the time delay difference of the optical fiber from the transmitter of the first baseband unit or the second baseband unit to the receiver of the radio frequency unit, then the preset rule is:

[0016]

[0017] Wherein, when T14>m / 2, T14=T14-m; when Toffset>m / 2, Toffset=Toffset-m, m is the period of the synchronization signal transmitted by the transmitter of the first baseband unit; T12 is used to characterize the time delay difference of the optical fiber from the transmitter of the first baseband unit or the second baseband unit to the receiver of the radio frequency unit; T34 characterizes the time delay difference of the optical fiber from the transmitter of the radio frequency unit to the receiver of the first baseband unit or the second baseband unit; T14 is used to characterize the time delay difference between the transmitter and receiver of the measurement optical port of the first baseband unit or the second baseband unit; Toffset is used to characterize the transmit and receive time delay difference of the first optical port or the second optical port of the radio frequency unit.

[0018] In one possible implementation, if the radio frequency unit includes at least two radio frequency units, and the second response information includes the delay difference between the optical ports corresponding to the at least two radio frequency units and the transmit / receive delay difference within the optical ports of each radio frequency unit;

[0019] Based on the delay difference in the first response information, the second response information, and preset rules, the delay difference from the first baseband unit to the radio frequency unit and the delay difference from the second baseband unit to the radio frequency unit for each of the two optical fibers are determined, including:

[0020] The third delay difference is determined based on the delay difference within the optical port of the first radio frequency unit closest to the first baseband unit and the transmit / receive delay difference of the first baseband unit.

[0021] A fourth delay difference is determined based on the delay difference within the optical port of the nearest adjacent radio frequency unit and the delay difference within the optical port of the next radio frequency unit of the adjacent radio frequency unit.

[0022] The fifth delay difference is determined based on the delay difference between the optical ports corresponding to each radio frequency unit;

[0023] Based on the delay difference in the first response information and the transmit / receive delay difference in the optical port of the last radio frequency unit among the radio frequency units connected to the second baseband unit, a sixth delay difference between the last radio frequency unit among the radio frequency units and the second baseband unit is determined.

[0024] Based on the sum of the third delay difference, the fourth delay difference, the fifth delay difference, and the sixth delay difference, the delay difference from the first baseband unit to the radio frequency unit and the delay difference from the second baseband unit to the radio frequency unit of each of the two optical fibers are determined.

[0025] Secondly, embodiments of the present invention provide an apparatus for measuring the delay of a bidirectional connection with two optical fibers, including a memory, a transceiver, and a processor:

[0026] A memory for storing computer programs; a transceiver for sending and receiving data under the control of the processor; and a processor for reading the computer programs from the memory and performing the following operations:

[0027] Send a delay measurement handshake request to the second baseband unit;

[0028] The system receives a first response message from the second baseband unit in response to the delay measurement handshake request. The first response message includes the delay difference between the optical port transmitter and receiver measured by the second baseband unit.

[0029] Send a delay measurement request to the radio frequency unit and receive a second response from the radio frequency unit to the delay measurement request;

[0030] Based on the time delay difference in the first response information, the second response information, and the preset rules, the time delay difference from the first baseband unit to the radio frequency unit and the time delay difference from the second baseband unit to the radio frequency unit of each of the two optical fibers are determined.

[0031] In one possible implementation, if the radio frequency unit includes only one radio frequency unit, and the synchronization signals of the first baseband unit and the second baseband unit are aligned, then the preset rule is:

[0032] Based on the transmit / receive delay difference within the first optical port in the second response message and the delay difference between the transmitter and receiver of the measurement optical port of the first baseband unit, a first delay difference is determined; wherein, the first optical port is the optical port of the radio frequency unit closer to the first baseband unit; the first delay difference is the delay difference from the first baseband unit to the radio frequency unit corresponding to the dual optical fibers;

[0033] Based on the transmit / receive delay difference in the second optical port in the second response message and the delay difference in the first response message, a second delay difference is determined; wherein, the second optical port is the optical port of the radio frequency unit closer to the second baseband unit; the second delay difference is the delay difference from the second baseband unit to the radio frequency unit corresponding to the dual optical fibers.

[0034] In one possible implementation, if the radio frequency unit includes only one radio frequency unit, and the synchronization signals of the first baseband unit and the second baseband unit are not aligned, and the period of the synchronization signal transmitted by the transmitter of the first baseband unit is much greater than the time delay difference of the optical fiber from the transmitter of the first baseband unit or the second baseband unit to the receiver of the radio frequency unit, then the preset rule is:

[0035]

[0036] Wherein, when T14>m / 2, T14=T14-m; when Toffset>m / 2, Toffset=Toffset-m, m is the period of the synchronization signal transmitted by the transmitter of the first baseband unit; T12 is used to characterize the time delay difference of the optical fiber from the transmitter of the first baseband unit or the second baseband unit to the receiver of the radio frequency unit; T34 characterizes the time delay difference of the optical fiber from the transmitter of the radio frequency unit to the receiver of the first baseband unit or the second baseband unit; T14 is used to characterize the time delay difference between the transmitter and receiver of the measurement optical port of the first baseband unit or the second baseband unit; Toffset is used to characterize the transmit and receive time delay difference of the first optical port or the second optical port of the radio frequency unit.

[0037] In one possible implementation, if the radio frequency unit includes at least two radio frequency units, and the second response information includes the delay difference between the optical ports corresponding to the at least two radio frequency units and the transmit / receive delay difference within the optical ports of each radio frequency unit; then the processor is configured to execute:

[0038] The third delay difference is determined based on the delay difference within the optical port of the first radio frequency unit closest to the first baseband unit and the transmit / receive delay difference of the first baseband unit.

[0039] A fourth delay difference is determined based on the delay difference within the optical port of the nearest adjacent radio frequency unit and the delay difference within the optical port of the next radio frequency unit of the adjacent radio frequency unit.

[0040] The fifth delay difference is determined based on the delay difference between the optical ports corresponding to each radio frequency unit;

[0041] Based on the delay difference in the first response information and the transmit / receive delay difference in the optical port of the last radio frequency unit among the radio frequency units connected to the second baseband unit, a sixth delay difference between the last radio frequency unit among the radio frequency units and the second baseband unit is determined.

[0042] Based on the sum of the third delay difference, the fourth delay difference, the fifth delay difference, and the sixth delay difference, the delay difference from the first baseband unit to the radio frequency unit and the delay difference from the second baseband unit to the radio frequency unit of each of the two optical fibers are determined.

[0043] Thirdly, embodiments of the present invention provide an apparatus for measuring the delay of a bidirectional connection using two optical fibers, applied to a first baseband unit, wherein the first baseband unit, the radio frequency unit, and the second baseband unit transmit signals through the two optical fibers, the apparatus comprising:

[0044] The first transmitting unit is used to send a delay measurement handshake request to the second baseband unit;

[0045] The first receiving unit is configured to receive first response information from the second baseband unit in response to the delay measurement handshake request, wherein the first response information includes the delay difference between the optical port transmitter and receiver measured by the second baseband unit.

[0046] The second transmitting unit is used to send a delay measurement request to the radio frequency unit;

[0047] The second receiving unit is used to receive the second response information of the radio frequency unit to the delay measurement request;

[0048] The processing unit is configured to determine, based on the delay difference in the first response information, the second response information, and a preset rule, the delay difference between the two optical fibers from the first baseband unit to the radio frequency unit, and the delay difference between the second baseband unit to the radio frequency unit.

[0049] Fourthly, embodiments of the present invention provide a processor-readable storage medium storing a computer program for causing the processor to perform the method as described in any one of the first aspects.

[0050] In this embodiment of the invention, the first baseband unit can send a delay measurement handshake request to the second baseband unit, thereby obtaining the delay difference between the transmitter and receiver of the optical port measured by the second baseband unit. In other words, this embodiment provides a bidirectional dual-fiber delay measurement process, adding a handshake step between the two baseband units, i.e., adding a handshake process between the first and second baseband units, thereby obtaining the transmit-receive time difference of the second baseband unit. Further, the first baseband unit sends a delay measurement request to the radio frequency (RF) unit, and can obtain a second response message sent by the RF unit. Based on the delay difference in the first response information, the second response information, and preset rules, the delay difference between the corresponding RF units of the two optical fibers and the first baseband unit, and the delay difference between the RF units and the second baseband unit, can be obtained.

[0051] As can be seen, the method for measuring the delay of bidirectional dual-fiber connections provided in this embodiment of the invention can measure the bidirectional fiber delay in one go, thus optimizing the existing fiber delay measurement process and shortening the fiber switching time. Attached Figure Description

[0052] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention, but do not constitute an undue limitation of the invention.

[0053] Figure 1 A schematic diagram of fiber optic delay measurement in a scenario where the baseband unit and radio frequency unit are directly connected in the existing technology;

[0054] Figure 2 This is a schematic diagram illustrating the latency relationship in a scenario where the baseband unit and radio frequency unit are directly connected in the prior art.

[0055] Figure 3 A schematic diagram of fiber optic delay measurement in a scenario where the baseband unit and radio frequency unit are linearly connected in existing technology;

[0056] Figure 4 This is a schematic diagram of fiber optic delay measurement in a bidirectional connection scenario provided by an embodiment of the present invention;

[0057] Figure 5 A flowchart illustrating the steps of a method for measuring the delay of a bidirectional connection using two optical fibers, provided in an embodiment of the present invention;

[0058] Figure 6 This is a schematic diagram illustrating the information interaction between the first baseband unit, the second baseband unit, and the radio frequency unit provided in an embodiment of the present invention.

[0059] Figure 7 This is a schematic diagram of fiber optic delay relationship in a bidirectional connection scenario provided by an embodiment of the present invention;

[0060] Figure 8 This is a schematic diagram of fiber optic delay relationship in a frame header misalignment scenario provided by an embodiment of the present invention;

[0061] Figure 9 This is a schematic diagram of fiber optic delay measurement in a cascaded bidirectional connection scenario provided by an embodiment of the present invention;

[0062] Figure 10 This invention provides a schematic diagram of fiber optic delay relationships in a scenario where the frame headers of a cascaded bidirectional connection are misaligned.

[0063] Figure 11 A schematic diagram of the physical architecture of a device for measuring the delay of a bidirectional connection with two optical fibers, provided in an embodiment of the present invention;

[0064] Figure 12 This is a schematic diagram of the logic architecture of a device for measuring the delay of a bidirectional connection with two optical fibers, provided in an embodiment of the present invention. Detailed Implementation

[0065] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention. Unless otherwise specified, the embodiments and features in the embodiments of this invention can be arbitrarily combined with each other. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be performed in a different order than that shown here.

[0066] As mentioned earlier, in the existing technology, when measuring fiber delay in a scenario where the baseband unit (BBU) and radio element (RE) are directly connected, the fiber delay measurement scheme with unidirectional connection of the radio element is generally adopted.

[0067] For details, please refer to Figure 1 , Figure 1 This diagram illustrates fiber optic delay measurement in a direct-connection scenario between the baseband unit and the radio frequency unit (RF unit) in existing technology. It is evident that it is necessary to determine the delay difference T12 between the baseband unit (BBU) and its optical port transmitter R1 and receiver R2, the delay difference Toffset between the RF unit (RE) and its transmitter R3, the delay difference T34 between the RF unit (RE) and its receiver R4, and the delay difference T14 between the baseband unit (BBU) and its receiver R2. This allows us to obtain the fiber optic delay difference between the baseband unit (BBU) and the RF unit (RE).

[0068] Further, please refer to Figure 2 , Figure 2 This diagram illustrates the latency relationship in a direct-connection scenario between the baseband unit and the radio frequency unit in existing technologies. Figure 2 It can be seen that T12, T23, T34, T14, and Toffset have the relationship shown in Formula 1:

[0069]

[0070] Therefore, the fiber delay difference T12 can be determined based on Formula 1.

[0071] Furthermore, in specific implementations, there are also linear connection scenarios, i.e., scenarios where two optical fibers connect one baseband unit to multiple radio frequency units, such as two-level interconnection scenarios, i.e., scenarios where two optical fibers connect one baseband unit to two radio frequency units. Please refer to [link to relevant documentation]. Figure 3 As shown, Figure 3 This is a schematic diagram of fiber optic delay measurement in a scenario where the baseband unit and radio frequency unit are linearly connected in the existing technology.

[0072] based on Figure 3 As shown, for a two-stage cascaded scenario, the delay difference between the preceding and following stages can be measured separately. Specifically, the delay of the first-stage fiber can be determined based on the following formula 2:

[0073]

[0074] Furthermore, the delay of the second-stage fiber can be determined based on the following formula 3:

[0075] The second-level fiber delay measurement is as follows:

[0076]

[0077] Furthermore, by combining TBdelayDL_1 and TBdelayUL_1 reported by the first-level radio frequency unit RE1 and the following formula 3, the fiber optic delay difference between RE2 and BBU can be obtained as follows:

[0078]

[0079] It should be noted that the above delay measurements are all based on the BBU-side fiber frame synchronization signal sync_byte, meaning that the synchronization signal reference for each port is consistent.

[0080] Please see Figure 4 , Figure 4 This is a schematic diagram illustrating fiber optic delay measurement in a bidirectional connection scenario, provided as an embodiment of the present invention. Specifically, for a bidirectional connection scenario... Figure 4 The radio frequency unit RE2 is connected to both the baseband unit BBU1 and the baseband unit BBU2, meaning that the optical fiber delay in both directions needs to be measured, but the synchronization signals in both directions are inconsistent.

[0081] Currently, the determination of bidirectional fiber delay is usually performed using the aforementioned method, with a delay measurement conducted once when the RF unit RE2 is connected to the baseband unit BBU1. At this point, only the delay of one fiber can be obtained, for example... Figure 4 T12(1) is shown in the figure. When T12(1) corresponds to a fiber optic fault, the time delay needs to be measured again, that is, when the radio frequency unit RE2 is connected to the baseband unit BBU2, a time delay measurement is performed, and only T12(2) can be obtained at this time.

[0082] As can be seen, current fiber optic delay measurement methods for bidirectional connections rely on frame header alignment at the transmitting and receiving ends. However, in scenarios where the frame headers are misaligned, only unidirectional delay can be measured separately, requiring two delay measurement processes to measure bidirectional fiber optic delay. Furthermore, the need for two delay measurement processes involves a handshake between the RF unit and the baseband unit, increasing fiber switching time. For high-reliability scenarios, uninterrupted service is required during fiber switching; therefore, it is necessary to further optimize the fiber switching process and shorten the switching time.

[0083] Therefore, this invention provides a method and apparatus for measuring the delay of two optical fibers in a bidirectional connection. This method allows for the simultaneous measurement of the delay of two optical fibers, reducing fiber switching time.

[0084] Please refer to Figure 5 This invention provides a method for measuring the delay of a bidirectional connection using two optical fibers. The method is applied to a first baseband unit, and the first baseband unit, the radio frequency unit, and the second baseband unit transmit signals through two optical fibers. The specific processing steps of this method are as follows.

[0085] Step 501: Send a delay measurement handshake request to the second baseband unit.

[0086] Step 502: Receive the first response information of the second baseband unit to the delay measurement handshake request. The first response information includes the delay difference between the optical port transmitter and receiver measured by the second baseband unit.

[0087] Step 503: Send a delay measurement request to the radio frequency unit and receive the second response information from the radio frequency unit to the delay measurement request.

[0088] Step 504: Based on the delay difference in the first response information, the second response information, and the preset rules, determine the delay difference from the first baseband unit to the radio frequency unit and the delay difference from the second baseband unit to the radio frequency unit for each of the two optical fibers.

[0089] In this embodiment of the invention, a method is provided for a bidirectional connection scenario during a single fiber delay measurement, for example... Figure 4The diagram illustrates the fiber delay between the RF unit RE2 and the baseband unit BBU1, and the method for measuring the fiber delay between the RF unit RE2 and the baseband unit BBU2. Specifically, during the fiber delay measurement process, the baseband unit BBU1 can receive the transmit / receive delay difference Toffset(1) and the transmit / receive delay difference Toffset(2) of optical port 1 reported by the RF unit RE2, and the transmit / receive delay difference T14(2) of optical port reported by the baseband unit BBU2. The baseband unit BBU1 can also determine its corresponding transmit / receive delay difference T14(1), thereby the baseband unit BBU1 can determine the delay difference corresponding to the two fibers based on the received delay difference information and the determined delay difference. Furthermore, the solution provided in this embodiment adds a handshake between the two baseband units in the delay measurement process.

[0090] To better illustrate the method for measuring the delay of a bidirectional connection using two optical fibers provided by this invention, please refer to [link to relevant documentation]. Figure 6 As shown, Figure 6 This is a schematic diagram illustrating the information interaction between the first baseband unit, the second baseband unit, and the radio frequency unit provided in an embodiment of the present invention.

[0091] Step 601: The first baseband unit sends a delay measurement handshake request to the second baseband unit.

[0092] Step 602: The second baseband unit returns a first response message to the first baseband unit, wherein the first response message includes the time delay difference between the optical port transmitter and receiver measured by the second baseband unit.

[0093] Step 603: The first baseband unit sends a delay measurement request to the radio frequency unit.

[0094] Step 604: The radio frequency unit returns a second response message to the first baseband unit; wherein the second response message includes the delay difference between the optical ports corresponding to at least two radio frequency units and the transmit / receive delay difference within the optical ports of each radio frequency unit.

[0095] Step 605: The first baseband unit reads the first response message and the second response message, and calculates the time delay difference between the two optical fibers from the first baseband unit to the radio frequency unit, and the time delay difference between the two optical fibers from the second baseband unit to the radio frequency unit.

[0096] Step 606: The first baseband unit sends the delay measurement result configuration information to the radio frequency unit.

[0097] Step 607: The radio frequency unit returns the third response message corresponding to the delay measurement result to the first baseband unit.

[0098] Specifically, in this embodiment of the invention, the first baseband unit can be understood as... Figure 4The baseband unit BBU1 and the second baseband unit shown can be understood as... Figure 4 The baseband unit BBU2 and the radio frequency unit shown can be understood as... Figure 4 The radio frequency unit RE2 is shown in the figure. It should be noted that the delay measurement method shown in this embodiment of the invention uses the synchronization signal of the optical port transmitter of baseband unit BBU1 as the reference, that is, baseband unit BBU1 is the main baseband unit. In actual embodiments, baseband unit BBU2 can also be determined as the main baseband unit. This embodiment of the invention does not limit this.

[0099] In this embodiment of the invention, considering a bidirectional connection scenario, it may be a bidirectional connection scenario where only one radio frequency unit is included between two baseband units, or a scenario where two baseband units are connected by two radio frequency units, or a scenario where two baseband units are connected by more than two radio frequency units, etc. To more clearly illustrate the dual-fiber delay measurement scheme in a bidirectional connection scenario provided by this invention, two specific embodiments are described below.

[0100] Example 1:

[0101] For example, if the radio frequency unit includes only one radio frequency unit, i.e., a bidirectional connection scenario is... Figure 4 For the bidirectional connection scenario shown, please refer to [link / reference]. Figure 7 As shown, Figure 7 This is a schematic diagram of the fiber optic delay relationship in a bidirectional connection scenario according to an embodiment of the present invention. In this connection scenario, the synchronization signals of the first baseband unit and the second baseband unit are aligned. The preset rule is as follows: A first delay difference is determined based on the transmit / receive delay difference within the first optical port in the second response message and the delay difference between the transmitter and receiver of the measurement optical port of the first baseband unit. Here, the first optical port is the optical port of the radio frequency unit closest to the first baseband unit; the first delay difference is the delay difference from the first baseband unit to the radio frequency unit corresponding to the dual optical fibers. Furthermore, a second delay difference is determined based on the transmit / receive delay difference within the second optical port in the second response message and the delay difference in the first response message. Here, the second optical port is the optical port of the radio frequency unit closest to the second baseband unit; the second delay difference is the delay difference from the second baseband unit to the radio frequency unit corresponding to the dual optical fibers.

[0102] For details, please see Figure 4 As shown, based on preset rules and the first and second response messages, the time delay difference from the first baseband unit to the radio frequency unit for each of the two optical fibers, and the time delay difference from the second baseband unit to the radio frequency unit, can be calculated in the following way:

[0103]

[0104] Wherein, T12(1) is used to characterize the first time delay difference of the first optical fiber from the transmitter of the first baseband unit to the receiver of the first optical port of the radio frequency unit; T12(2) is used to characterize the second time delay difference of the second optical fiber from the transmitter of the second baseband unit to the receiver of the second optical port of the radio frequency unit; T34(1) is used to characterize the first time delay difference of the second optical fiber from the transmitter of the first optical port of the radio frequency unit to the receiver of the first baseband unit; T34(2) is used to characterize the second time delay difference of the first optical fiber from the transmitter of the second optical port of the radio frequency unit to the receiver of the second baseband unit; T14(1) is used to characterize the time delay difference from the transmitter of the measurement optical port of the first baseband unit to the receiver; T14(2) is used to characterize the time delay difference from the transmitter of the measurement optical port of the second baseband unit to the receiver; Toffset(1) is used to characterize the transmit / receive time delay difference of the first optical port; Toffset(2) is used to characterize the transmit / receive time delay difference of the second optical port.

[0105] For example, considering that the RF unit includes only one RF unit, and the synchronization signals of the first baseband unit and the second baseband unit are not aligned, the period during which the transmitter of the first baseband unit sends the synchronization signal is much greater than the time delay difference of the optical fiber from the transmitter of the first baseband unit or the second baseband unit to the receiver of the RF unit. Please refer to [link to relevant documentation]. Figure 8 As shown, Figure 8 This is a schematic diagram of the fiber optic delay relationship in a frame header misalignment scenario according to an embodiment of the present invention. The preset rule is as follows:

[0106]

[0107] Wherein, when T14>m / 2, T14=T14-m; when Toffset>m / 2, Toffset=Toffset-m, where m is the period of the synchronization signal transmitted by the transmitter of the first baseband unit; T12 is used to characterize the time delay difference of the optical fiber from the transmitter of the first baseband unit or the second baseband unit to the receiver of the radio frequency unit; T34 is used to characterize the time delay difference of the optical fiber from the transmitter of the radio frequency unit to the receiver of the first baseband unit or the second baseband unit; T14 is used to characterize the time delay difference between the transmitter and receiver of the measurement optical port of the first baseband unit or the second baseband unit; Toffset is used to characterize the transmit and receive time delay difference of the first optical port or the second optical port of the radio frequency unit.

[0108] For example, assuming m = 10ms, the delay difference Tx between the receiver and transmitter, where the delay is less than or equal to 5ms, is defined as positive, and the delay greater than 5ms is defined as negative (Tx - 10ms). Since the synchronization signals of BBU1 and BBU2 are not necessarily aligned, for the two optical ports of RE2, receiving from R2 / R2(2) and transmitting from R3 / R3(2), the delay difference may be negative, meaning the frame header of R3 / R3(2) may precede the frame header of R2 / R2(2). The delay measurement for each fiber segment may be as follows: Figure 8Given the four cases shown (Case A to Case D), the preset rule corresponding to Formula 5 can be modified to the preset rule corresponding to Formula 6.

[0109] It should be noted that Formula 6 can be applied to both linear connection scenarios of the original radio frequency units and ring connection scenarios.

[0110] Example 2:

[0111] In this embodiment of the invention, if the radio frequency unit includes at least two radio frequency units, and the second response information includes the time delay difference between the optical ports corresponding to the at least two radio frequency units and the transmit / receive time delay difference within the optical ports of each radio frequency unit; then, based on the time delay difference in the first response information, the second response information, and a preset rule, the time delay difference between the first baseband unit and the second baseband unit of each of the two optical fibers can be determined by, but is not limited to, the following steps:

[0112] Step a: Determine the third delay difference based on the delay difference within the optical port of the first radio frequency unit closest to the first baseband unit and the transmit / receive delay difference of the first baseband unit;

[0113] Step b: Determine the fourth delay difference based on the delay difference within the optical port of the nearest adjacent RF unit and the delay difference within the optical port of the next RF unit in each RF unit;

[0114] Step c: Determine the fifth delay difference based on the delay difference between the optical ports corresponding to each RF unit;

[0115] Step d: Based on the delay difference in the first response information and the transmit / receive delay difference in the optical port of the last radio frequency unit among the radio frequency units connected to the second baseband unit, determine the sixth delay difference between the last radio frequency unit and the second baseband unit.

[0116] Step e: Based on the sum of the third, fourth, fifth, and sixth delay differences, determine the delay difference from the first baseband unit to the radio frequency unit and the delay difference from the second baseband unit to the radio frequency unit for each of the two optical fibers.

[0117] To better illustrate the fiber delay determination method for cascaded bidirectional connection scenarios provided by this invention, this embodiment of the invention will use the example of connecting only two radio frequency units between the first baseband unit and the second baseband unit.

[0118] Please see Figure 9 , Figure 9 This is a schematic diagram illustrating fiber optic delay measurement in a cascaded bidirectional connection scenario provided by an embodiment of the present invention. Also, please refer to... Figure 10 , Figure 10This is a schematic diagram illustrating the fiber delay relationship in a scenario where the frame headers of a cascaded bidirectional connection are misaligned, as provided in an embodiment of the present invention.

[0119] In this embodiment of the invention, the fiber delay can be calculated in segments according to Formula 6, and then the bidirectional fiber delay corresponding to the radio frequency unit RE2 can be obtained by combining Formula 4. The technical method for calculating the bidirectional fiber delay corresponding to the radio frequency unit RE1 is the same as that for calculating the bidirectional fiber delay corresponding to RE2.

[0120] Specifically, the fiber delay difference between the transmitter of baseband unit BBU1 and the receiver RB2 of RF unit RE2, and the fiber delay difference between the transmitter RB3 of RF unit RE2 and the receiver R4 of baseband unit BBU1, can be determined by the following formula 7:

[0121]

[0122] Specifically, the fiber optic delay difference between the transmitter RB1 of RF unit RE1 and the receiver R2 of RF unit RE2, and the fiber optic delay difference between the transmitter R3 of RF unit RE2 and the receiver RB4 of RF unit RE1, can be determined by the following formula 8:

[0123]

[0124] Furthermore, by combining TBdelayDL_1 and TBdelayUL_1 reported by RF unit RE1 and the following formula 9, the fiber optic delay difference between RF unit RE2 and baseband unit BBU1 can be calculated as follows:

[0125]

[0126] Furthermore, the fiber delay difference between the RF unit RE2 and the baseband unit BBU2 can be determined based on the following formula 10:

[0127]

[0128] Therefore, the delay difference corresponding to the two optical fibers can be obtained based on Formulas 9 and 10. It should be noted that, in this embodiment of the invention, when two or more radio frequency units are connected between two baseband units, the delay difference of the last optical fiber corresponding to the radio frequency unit connected to the second baseband unit can be determined with reference to Formula 10, and the delay difference of the multiple optical fibers before the radio frequency unit connected to the second baseband unit can be determined by extending Formula 9, which will not be elaborated here.

[0129] As can be seen, this invention provides a fiber optic delay measurement method for ring networks, which can simultaneously measure bidirectional fiber delay without relying on bidirectional frame header alignment. Furthermore, this method can simultaneously measure the bidirectional fiber delay corresponding to each radio frequency unit (RF unit) in a ring connection. Clearly, the fiber optic delay measurement method proposed in this invention can be applied not only to ring connection scenarios but also to linear connection scenarios. Moreover, this method can optimize the fiber optic delay measurement process and shorten fiber switching time, making it highly valuable for high-reliability networking scenarios.

[0130] Based on the same inventive concept, see [reference] Figure 11 As shown, this embodiment of the invention provides an apparatus for measuring the delay of a bidirectional connection using two optical fibers, including a memory 1101, a transceiver 1102, and a processor 1103.

[0131] Memory 1101 is used to store computer programs; transceiver 1102 is used to send and receive data under the control of the processor; processor 1103 is used to read the computer programs in the memory and perform the following operations:

[0132] Send a delay measurement handshake request to the second baseband unit;

[0133] The system receives a first response message from the second baseband unit in response to the delay measurement handshake request. The first response message includes the delay difference between the optical port transmitter and receiver measured by the second baseband unit.

[0134] Send a delay measurement request to the radio frequency unit and receive a second response from the radio frequency unit to the delay measurement request;

[0135] Based on the time delay difference in the first response information, the second response information, and the preset rules, the time delay difference from the first baseband unit to the radio frequency unit and the time delay difference from the second baseband unit to the radio frequency unit of each of the two optical fibers are determined.

[0136] In one possible implementation, if the radio frequency unit includes only one radio frequency unit, and the synchronization signals of the first baseband unit and the second baseband unit are aligned, then the preset rule is:

[0137] Based on the transmit / receive delay difference within the first optical port in the second response message and the delay difference between the transmitter and receiver of the measurement optical port of the first baseband unit, a first delay difference is determined; wherein, the first optical port is the optical port of the radio frequency unit closer to the first baseband unit; the first delay difference is the delay difference from the first baseband unit to the radio frequency unit corresponding to the dual optical fibers;

[0138] Based on the transmit / receive delay difference in the second optical port in the second response message and the delay difference in the first response message, a second delay difference is determined; wherein, the second optical port is the optical port of the radio frequency unit closer to the second baseband unit; the second delay difference is the delay difference from the second baseband unit to the radio frequency unit corresponding to the dual optical fibers.

[0139] In one possible implementation, if the radio frequency unit includes only one radio frequency unit, and the synchronization signals of the first baseband unit and the second baseband unit are not aligned, and the period of the synchronization signal transmitted by the transmitter of the first baseband unit is much greater than the time delay difference of the optical fiber from the transmitter of the first baseband unit or the second baseband unit to the receiver of the radio frequency unit, then the preset rule is:

[0140]

[0141] Wherein, when T14>m / 2, T14=T14-m; when Toffset>m / 2, Toffset=Toffset-m, m is the period of the synchronization signal transmitted by the transmitter of the first baseband unit; T12 is used to characterize the time delay difference of the optical fiber from the transmitter of the first baseband unit or the second baseband unit to the receiver of the radio frequency unit; T34 characterizes the time delay difference of the optical fiber from the transmitter of the radio frequency unit to the receiver of the first baseband unit or the second baseband unit; T14 is used to characterize the time delay difference between the transmitter and receiver of the measurement optical port of the first baseband unit or the second baseband unit; Toffset is used to characterize the transmit and receive time delay difference of the first optical port or the second optical port of the radio frequency unit.

[0142] In one possible implementation, if the radio frequency unit includes at least two radio frequency units, and the second response information includes the delay difference between the at least two radio frequency units and the transmit / receive delay difference of each radio frequency unit; then the processor 1103 is configured to execute:

[0143] The third delay difference is determined based on the delay difference within the optical port of the first radio frequency unit closest to the first baseband unit and the transmit / receive delay difference of the first baseband unit.

[0144] A fourth delay difference is determined based on the delay difference within the optical port of the nearest adjacent radio frequency unit and the delay difference within the optical port of the next radio frequency unit of the adjacent radio frequency unit.

[0145] The fifth delay difference is determined based on the delay difference between the optical ports corresponding to each radio frequency unit;

[0146] Based on the delay difference in the first response information and the transmit / receive delay difference in the optical port of the last radio frequency unit among the radio frequency units connected to the second baseband unit, a sixth delay difference between the last radio frequency unit among the radio frequency units and the second baseband unit is determined.

[0147] Based on the sum of the third delay difference, the fourth delay difference, the fifth delay difference, and the sixth delay difference, the delay difference from the first baseband unit to the radio frequency unit and the delay difference from the second baseband unit to the radio frequency unit of each of the two optical fibers are determined.

[0148] Based on the same inventive concept, see [reference] Figure 12 As shown, this embodiment of the invention provides a device for measuring the delay of a bidirectional dual-fiber connection, applied to a first baseband unit, wherein the first baseband unit, the radio frequency unit, and the second baseband unit transmit signals through the dual optical fibers. The device includes:

[0149] The first transmitting unit 1201 is used to send a delay measurement handshake request to the second baseband unit;

[0150] The first receiving unit 1202 is used to receive the first response information of the second baseband unit to the delay measurement handshake request, wherein the first response information includes the delay difference between the optical port transmitter and receiver measured by the second baseband unit.

[0151] The second transmitting unit 1203 is used to send a delay measurement request to the radio frequency unit;

[0152] The second receiving unit 1204 is used to receive the second response information of the radio frequency unit to the delay measurement request;

[0153] The processing unit 1205 is configured to determine, based on the delay difference in the first response information, the second response information, and a preset rule, the delay difference from the first baseband unit to the radio frequency unit and the delay difference from the second baseband unit to the radio frequency unit for each of the two optical fibers.

[0154] In this embodiment of the invention, the aforementioned first transmitting unit 1201, first receiving unit 1202, second transmitting unit 1203, second receiving unit 1204, and processing unit 1205 cooperate with each other to achieve the above-described embodiments. Figure 5 The method described herein for measuring the delay of a bidirectional connection with two optical fibers can be performed using any of these methods.

[0155] Based on the same inventive concept, embodiments of the present invention provide a processor-readable storage medium storing a computer program for causing the processor to execute a method for measuring the delay of a bidirectional connection with two optical fibers.

[0156] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0157] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing device, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0158] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0159] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the functions specified in one or more boxes. Obviously, those skilled in the art can make various modifications and variations to this invention without departing from the spirit and scope of the invention. Therefore, if these modifications and variations of the invention fall within the scope of the claims of the invention and their equivalents, the invention is also intended to include these modifications and variations.

Claims

1. A method for measuring the time delay of a bidirectional connection with two optical fibers, characterized in that, The method, which is applied to a first baseband unit and transmits signals between the first baseband unit, the radio frequency unit, and the second baseband unit via the dual optical fibers, includes: Send a delay measurement handshake request to the second baseband unit; The system receives a first response message from the second baseband unit in response to the delay measurement handshake request. The first response message includes the delay difference between the optical port transmitter and receiver measured by the second baseband unit. Send a delay measurement request to the radio frequency unit and receive a second response from the radio frequency unit to the delay measurement request; Based on the delay difference in the first response information, the second response information, and the preset rules, the delay difference from the first baseband unit to the radio frequency unit and the delay difference from the second baseband unit to the radio frequency unit of each of the two optical fibers are determined. If the radio frequency unit includes only one radio frequency unit, and the synchronization signals of the first baseband unit and the second baseband unit are aligned, then the preset rule is as follows: A first delay difference is determined based on the transmit / receive delay difference within the first optical port in the second response information and the delay difference between the transmitter and receiver of the measurement optical port of the first baseband unit; wherein the first optical port is the optical port of the radio frequency unit closest to the first baseband unit; the first delay difference is the delay difference from the first baseband unit to the radio frequency unit corresponding to the dual optical fibers; a second delay difference is determined based on the transmit / receive delay difference within the second optical port in the second response information and the delay difference in the first response information; wherein the second optical port is the optical port of the radio frequency unit closest to the second baseband unit; the second delay difference is the delay difference from the second baseband unit to the radio frequency unit corresponding to the dual optical fibers; If the radio frequency unit includes only one radio frequency unit, and the synchronization signals of the first baseband unit and the second baseband unit are not aligned, and the period of the synchronization signal transmitted by the transmitter of the first baseband unit is much greater than the time delay difference of the optical fiber from the transmitter of the first baseband unit or the second baseband unit to the receiver of the radio frequency unit, then the preset rule is: Where, when T14 > m / 2, T14 = T14 - m; when Toffset > m / 2, Toffset = -m, where m is the period for the transmitter of the synchronization signal in the first baseband unit; T12 is used to characterize the time delay difference of the optical fiber from the transmitter of the first baseband unit or the second baseband unit to the receiver of the radio frequency unit; T34 is used to characterize the time delay difference of the optical fiber from the transmitter of the radio frequency unit to the receiver of the first baseband unit or the second baseband unit; T14 is used to characterize the time delay difference between the transmitter and receiver of the measurement optical port of the first baseband unit or the second baseband unit; Toffset is used to characterize the transmit and receive time delay difference of the first optical port or the second optical port of the radio frequency unit.

2. The method as described in claim 1, characterized in that, If the radio frequency unit includes at least two radio frequency units, and the second response information includes the delay difference between the optical ports corresponding to the at least two radio frequency units and the transmit / receive delay difference within the optical ports of each radio frequency unit; Based on the delay difference in the first response information, the second response information, and preset rules, the delay difference from the first baseband unit to the radio frequency unit and the delay difference from the second baseband unit to the radio frequency unit for each of the two optical fibers are determined, including: The third delay difference is determined based on the delay difference within the optical port of the first radio frequency unit closest to the first baseband unit and the transmit / receive delay difference of the first baseband unit. A fourth delay difference is determined based on the delay difference within the optical port of the nearest adjacent radio frequency unit and the delay difference within the optical port of the next radio frequency unit of the adjacent radio frequency unit. The fifth delay difference is determined based on the delay difference between the optical ports corresponding to each radio frequency unit; Based on the delay difference in the first response information and the transmit / receive delay difference in the optical port of the last radio frequency unit among the radio frequency units connected to the second baseband unit, a sixth delay difference between the last radio frequency unit among the radio frequency units and the second baseband unit is determined. Based on the sum of the third delay difference, the fourth delay difference, the fifth delay difference, and the sixth delay difference, the delay difference from the first baseband unit to the radio frequency unit and the delay difference from the second baseband unit to the radio frequency unit of each of the two optical fibers are determined.

3. A device for measuring the delay of a bidirectional connection with two optical fibers, characterized in that, The device, which is applied to a first baseband unit and transmits signals between the first baseband unit, the radio frequency unit, and the second baseband unit via the dual optical fibers, includes a memory, a transceiver, and a processor. Memory, used to store computer programs; Transceiver, used to send and receive data under the control of the processor; Processor, configured to read the computer program in the memory and perform the following operations: Send a delay measurement handshake request to the second baseband unit; The system receives a first response message from the second baseband unit in response to the delay measurement handshake request. The first response message includes the delay difference between the optical port transmitter and receiver measured by the second baseband unit. Send a delay measurement request to the radio frequency unit and receive a second response from the radio frequency unit to the delay measurement request; Based on the delay difference in the first response information, the second response information, and the preset rules, the delay difference from the first baseband unit to the radio frequency unit and the delay difference from the second baseband unit to the radio frequency unit of each of the two optical fibers are determined. If the radio frequency unit includes only one radio frequency unit, and the synchronization signals of the first baseband unit and the second baseband unit are aligned, then the preset rule is as follows: A first delay difference is determined based on the transmit / receive delay difference within the first optical port in the second response information and the delay difference between the transmitter and receiver of the measurement optical port of the first baseband unit; wherein the first optical port is the optical port of the radio frequency unit closest to the first baseband unit; the first delay difference is the delay difference from the first baseband unit to the radio frequency unit corresponding to the dual optical fibers; a second delay difference is determined based on the transmit / receive delay difference within the second optical port in the second response information and the delay difference in the first response information; wherein the second optical port is the optical port of the radio frequency unit closest to the second baseband unit; the second delay difference is the delay difference from the second baseband unit to the radio frequency unit corresponding to the dual optical fibers; If the radio frequency unit includes only one radio frequency unit, and the synchronization signals of the first baseband unit and the second baseband unit are not aligned, and the period of the synchronization signal transmitted by the transmitter of the first baseband unit is much greater than the time delay difference of the optical fiber from the transmitter of the first baseband unit or the second baseband unit to the receiver of the radio frequency unit, then the preset rule is: Where, when T14 > m / 2, T14 = T14 - m; when Toffset > m / 2, Toffset = -m, where m is the period for the transmitter of the synchronization signal to be transmitted by the transmitter of the first baseband unit; T12 is used to characterize the time delay difference of the optical fiber from the transmitter of the first baseband unit or the second baseband unit to the receiver of the radio frequency unit; T34 is used to characterize the time delay difference of the optical fiber from the receiver of the first baseband unit or the second baseband unit to the transmitter of the radio frequency unit; T14 is used to characterize the time delay difference between the transmitter and receiver of the measurement optical port of the first baseband unit or the second baseband unit; Toffset is used to characterize the transmit and receive time delay difference of the first optical port or the second optical port of the radio frequency unit.

4. The apparatus as described in claim 3, characterized in that, If the radio frequency unit includes at least two radio frequency units, and the second response information includes the delay difference between the optical ports corresponding to the at least two radio frequency units and the transmit / receive delay difference within the optical ports of each radio frequency unit; then the processor is configured to execute: The third delay difference is determined based on the delay difference within the optical port of the first radio frequency unit closest to the first baseband unit and the transmit / receive delay difference of the first baseband unit. A fourth delay difference is determined based on the delay difference within the optical port of the nearest adjacent radio frequency unit and the delay difference within the optical port of the next radio frequency unit of the adjacent radio frequency unit. The fifth delay difference is determined based on the delay difference between the optical ports corresponding to each radio frequency unit; Based on the delay difference in the first response information and the transmit / receive delay difference in the optical port of the last radio frequency unit among the radio frequency units connected to the second baseband unit, a sixth delay difference between the last radio frequency unit among the radio frequency units and the second baseband unit is determined. Based on the sum of the third delay difference, the fourth delay difference, the fifth delay difference, and the sixth delay difference, the delay difference from the first baseband unit to the radio frequency unit and the delay difference from the second baseband unit to the radio frequency unit of each of the two optical fibers are determined.

5. An apparatus for measuring the delay of a bidirectional connection with two optical fibers, characterized in that, The device, which is applied to a first baseband unit and transmits signals between the first baseband unit, the radio frequency unit, and the second baseband unit via the dual optical fibers, comprises: The first transmitting unit is used to send a delay measurement handshake request to the second baseband unit; The first receiving unit is configured to receive first response information from the second baseband unit in response to the delay measurement handshake request, wherein the first response information includes the delay difference between the optical port transmitter and receiver measured by the second baseband unit. The second transmitting unit is used to send a delay measurement request to the radio frequency unit; The second receiving unit is used to receive the second response information of the radio frequency unit to the delay measurement request; The processing unit is configured to determine, based on the delay difference in the first response information, the second response information, and a preset rule, the delay difference between the two optical fibers from the first baseband unit to the radio frequency unit, and the delay difference between the second baseband unit to the radio frequency unit. If the radio frequency unit includes only one radio frequency unit, and the synchronization signals of the first baseband unit and the second baseband unit are aligned, then the preset rule is as follows: A first delay difference is determined based on the transmit / receive delay difference within the first optical port in the second response information and the delay difference between the transmitter and receiver of the measurement optical port of the first baseband unit; wherein the first optical port is the optical port of the radio frequency unit closest to the first baseband unit; the first delay difference is the delay difference from the first baseband unit to the radio frequency unit corresponding to the dual optical fibers; a second delay difference is determined based on the transmit / receive delay difference within the second optical port in the second response information and the delay difference in the first response information; wherein the second optical port is the optical port of the radio frequency unit closest to the second baseband unit; the second delay difference is the delay difference from the second baseband unit to the radio frequency unit corresponding to the dual optical fibers; If the radio frequency unit includes only one radio frequency unit, and the synchronization signals of the first baseband unit and the second baseband unit are not aligned, and the period of the synchronization signal transmitted by the transmitter of the first baseband unit is much greater than the time delay difference of the optical fiber from the transmitter of the first baseband unit or the second baseband unit to the receiver of the radio frequency unit, then the preset rule is: Where, when T14 > m / 2, T14 = T14 - m; when Toffset > m / 2, Toffset = -m, where m is the period for the transmitter of the synchronization signal in the first baseband unit; T12 is used to characterize the time delay difference of the optical fiber from the transmitter of the first baseband unit or the second baseband unit to the receiver of the radio frequency unit; T34 is used to characterize the time delay difference of the optical fiber from the transmitter of the radio frequency unit to the receiver of the first baseband unit or the second baseband unit; T14 is used to characterize the time delay difference between the transmitter and receiver of the measurement optical port of the first baseband unit or the second baseband unit; Toffset is used to characterize the transmit and receive time delay difference of the first optical port or the second optical port of the radio frequency unit.

6. A processor-readable storage medium, characterized in that, The processor-readable storage medium stores a computer program that causes the processor to perform the method of claim 1 or 2.

Images