WO2019223462A1 - 一种同步方法及接入点 - Google Patents

一种同步方法及接入点 Download PDF

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Publication number
WO2019223462A1
WO2019223462A1 PCT/CN2019/083181 CN2019083181W WO2019223462A1 WO 2019223462 A1 WO2019223462 A1 WO 2019223462A1 CN 2019083181 W CN2019083181 W CN 2019083181W WO 2019223462 A1 WO2019223462 A1 WO 2019223462A1
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WIPO (PCT)
Prior art keywords
access point
time
phase
tone signal
data frame
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PCT/CN2019/083181
Other languages
English (en)
French (fr)
Inventor
陈国海
袁方超
顾巍
陈鹏
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华为技术有限公司
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Application filed by 华为技术有限公司 filed Critical 华为技术有限公司
Priority to JP2020523726A priority Critical patent/JP6984014B2/ja
Priority to EP19807854.5A priority patent/EP3675389A4/en
Priority to KR1020207010924A priority patent/KR102351197B1/ko
Publication of WO2019223462A1 publication Critical patent/WO2019223462A1/zh

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/0413—MIMO systems
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/24—Radio transmission systems, i.e. using radiation field for communication between two or more posts
    • H04B7/26—Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile
    • H04B7/2662—Arrangements for Wireless System Synchronisation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/26—Systems using multi-frequency codes
    • H04L27/2601—Multicarrier modulation systems
    • H04L27/2647—Arrangements specific to the receiver only
    • H04L27/2655—Synchronisation arrangements
    • H04L27/2657—Carrier synchronisation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W56/00—Synchronisation arrangements
    • H04W56/001—Synchronization between nodes
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W56/00—Synchronisation arrangements
    • H04W56/001—Synchronization between nodes
    • H04W56/0015—Synchronization between nodes one node acting as a reference for the others
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W56/00—Synchronisation arrangements
    • H04W56/001—Synchronization between nodes
    • H04W56/002—Mutual synchronization
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W56/00—Synchronisation arrangements
    • H04W56/0035—Synchronisation arrangements detecting errors in frequency or phase
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/26—Systems using multi-frequency codes
    • H04L27/2601—Multicarrier modulation systems
    • H04L27/2602—Signal structure

Definitions

  • the present application relates to the field of communication technologies, and in particular, to a synchronization method and an access point.
  • each access point uses an independent crystal source. Because the crystal oscillators cannot be completely consistent, there are more or less slight frequency differences between the crystal oscillators. For example, a 10Mhz crystal oscillator may have a difference of 1PPM (parts-per-million).
  • 5G radio frequency carrier frequency
  • RF PLL Radio Frequency Phase Locked Loop
  • the relative phase of the signal received by the receiving end is continuously rotated, and the bit error rate increases until the receiving end cannot receive the signal.
  • the above signals are decoded.
  • the above-mentioned relative phase changes with time.
  • the larger the carrier frequency difference the faster the amount of change in phase difference, and the higher the bit error rate.
  • the reason for the higher bit error rate is as follows. As shown in Figure 1a, if there is a frequency difference between multiple access points on the transmitting end, the constellation mapping on the receiving end cannot be mapped to a predetermined position, and the mapping position is still It changes continuously over time, which leads to an increase in the bit error rate.
  • each access point is configured with a GPS clock module to receive the external GPS Clock, so as to achieve the purpose of the homogeneous crystal oscillator of the access point.
  • a GPS clock module to receive the external GPS Clock, so as to achieve the purpose of the homogeneous crystal oscillator of the access point.
  • the clock signal of the clock board is led to each access point as a reference clock by using a clock line configured externally. Therefore, the reference clock of each access point is a homogeneous clock signal output by the clock board, thereby achieving the purpose of the homogeneous crystal oscillator of the access point, and there is no frequency difference between the access points.
  • This solution requires additional clock board configuration and clock line deployment, which brings additional costs and time overhead.
  • the embodiments of the present application provide a synchronization method and an access point, which can reduce the system bit error rate.
  • an embodiment of the present application provides a synchronization method, including: a second access point receiving a mono signal sent by a first access point; and the second access point determining a first signal according to the mono signal The frequency difference between the carrier and the second carrier; the first carrier is used by the first access point to send the tone signal; the second carrier is used by the second access point to receive the tone signal ; The second access point performs phase compensation on the target data frame based on the frequency difference, so that the difference between the phase of the second carrier and the phase of the first carrier is less than or equal to a first threshold; Sending, by the second access point, the target data frame after phase compensation through the second carrier.
  • the second access point performs phase compensation on the target data frame by using a frequency difference, so that a difference between a phase of the second carrier and a phase of the first carrier is less than or equal to First threshold; therefore, the system bit error rate can be reduced.
  • the frequency difference is equal to a change amount of a phase difference of the tone signal in a unit time minus an original frequency of the tone signal
  • the mono signal is included in a first data frame, the first data frame further includes a target data frame, and the mono signal is in the first The time position in the data frame is earlier than the time position of the target data frame in the first data frame.
  • the method before the second access point receives the single-tone signal sent by the first access point, the method further includes that the second access point receives the first Instruction information sent by the access point; the instruction information is used to indicate the following parameters of the tone signal: the original frequency of the tone signal and the time position of the tone signal.
  • a change amount of a phase difference of the single tone signal in a unit time is determined by a phase difference of multiple sampling times in a duration of the single tone signal. This implementation manner can reduce the measurement error of the change amount of the phase difference of the tone signal in a unit time.
  • the multiple sampling times include sampling times within a duration of the multiple tone signals. This implementation manner can reduce the measurement error of the change amount of the phase difference of the tone signal in a unit time.
  • the frequency difference is equal to an average value of a change amount of phase differences of a plurality of the tone signals in a unit time minus the original of the tone signals frequency.
  • This implementation manner can further reduce the measurement error of the change amount of the phase difference of the tone signal in a unit time.
  • a change amount of a phase difference of the tone signal in a unit time is equal to a change amount of a phase difference of the tone signal in a first duration divided by Said first duration, said first duration being equal to a time interval between the duration of said two said mono signals and the duration of said two said mono signals being added.
  • This implementation manner can further reduce the measurement error of the change amount of the phase difference of the tone signal in a unit time.
  • the multiple sampling times within the duration of the mono signal include at least: a start time of the mono signal and an end time of the mono signal.
  • This implementation manner provides a preferred sampling time for sampling a single tone signal.
  • the second access point performs phase compensation on a target data frame based on the frequency difference, specifically: at an initial time of the target data frame, the The second access point performs phase compensation on the target data frame based on the frequency difference; or before the initial time of the target data frame, the second access point performs phase compensation on the target data frame based on the frequency difference; Or after the initial time of the target data frame, the second access point performs phase compensation on the target data frame based on the frequency difference.
  • This implementation manner provides three preferred timings for phase compensation, and the second access point may choose to perform phase compensation on the transmission signal modulated with the target data frame at any of the foregoing preferred compensation timings.
  • the phase compensation of the target data frame by the second access point may include the following two manners. First method: If the change amount of the phase difference of the single tone signal within unit time is small, the second access point uses the same compensation value to perform phase compensation on the target data frame during the duration of the target data frame. The second method: if the change amount of the phase difference of the single tone signal in the unit time is small, the second access point uses different compensation values for the target data at different sampling times during the duration of the target data frame. Frames are phase compensated.
  • This implementation mode provides different phase compensation schemes for different scenarios, which can reduce the computational complexity and improve the accuracy of phase compensation.
  • a time when the second access point sends the target data frame after phase compensation and a time when the first access point sends the target data frame is the same; the time at which the first access point sends the target data frame is the first time, and the first time is the time at a first time interval from the time when the first access point sends the phase abrupt value;
  • the phase abrupt value is included in the tone signal; the time when the second access point sends the target data frame is the second time, and the second time is when the phase is detected with the second access point
  • the abrupt edge is separated from the first time interval by a moment; the phase abrupt edge is associated with the phase abrupt value.
  • an embodiment of the present application provides a synchronization method, including: a first access point generating a single tone signal, where the single tone signal is used to determine a frequency difference between a first carrier and a second carrier; A carrier is used by the first access point to send the tone signal; the second carrier is used by the second access point to receive the tone signal; the first access point accesses the second access point Point to send the mono signal.
  • the first access point generates a single tone signal, which is used to determine the frequency difference between the first carrier and the second carrier; the frequency difference is used by the second access point to perform a target data frame Phase compensation so that the difference between the phase of the second carrier and the phase of the first carrier is less than or equal to the first threshold. Therefore, the system bit error rate can be reduced.
  • the frequency difference is equal to a change amount of a phase difference of the tone signal in a unit time minus an original frequency of the tone signal
  • the tone signal is included in a first data frame
  • the first data frame further includes the target data frame
  • the tone signal is in the first data frame.
  • the time position in the first data frame is earlier than the time position of the target data frame in the first data frame.
  • the method further includes: the first access point sends the second access point to the second access point.
  • the entry point sends instruction information; the instruction information is used to indicate the following parameters of the tone signal: the original frequency of the tone signal and the time position of the tone signal.
  • a change amount of a phase difference of the single tone signal in a unit time is determined by a phase difference of multiple sampling times within a duration of the single tone signal. This implementation manner can reduce the measurement error of the change amount of the phase difference of the tone signal in a unit time.
  • the multiple sampling times include sampling times within a duration of the multiple tone signals. This implementation manner can reduce the measurement error of the change amount of the phase difference of the tone signal in a unit time.
  • the frequency difference is equal to an average value of a change amount of phase differences of a plurality of the tone signals in a unit time minus an original value of the tone signals. frequency.
  • This implementation manner can further reduce the measurement error of the change amount of the phase difference of the tone signal in a unit time.
  • a change amount of a phase difference of the tone signal in a unit time is equal to a change amount of a phase difference of the tone signal in a first duration divided by Said first duration, said first duration being equal to a time interval between the duration of said two said mono signals and the duration of said two said mono signals being added.
  • This implementation manner can further reduce the measurement error of the change amount of the phase difference of the tone signal in a unit time.
  • the multiple sampling times within the duration of the tone signal include at least the start time of the tone signal and the end time of the tone signal. This implementation manner provides a preferred sampling time for sampling a single tone signal.
  • the processing unit performing phase compensation on the transmission signal modulated with the target data frame may include the following two manners.
  • the first method if the change amount of the phase difference of the single tone signal within a unit time is small, the processing unit uses the same compensation value to modulate the target data frame for the duration of the transmission signal modulated with the target data frame
  • the transmitted signal is phase-compensated.
  • the second method if the change amount of the phase difference of the mono signal within a unit time is small, the processing unit uses different compensation value pairs at different sampling times during the duration of the transmission signal with the target data frame modulated
  • the transmitted signal with the target data frame is modulated for phase compensation.
  • a time when the second access point sends the target data frame after phase compensation and a time when the first access point sends the target data frame is the same; the time at which the first access point sends the target data frame is the first time, and the first time is the time at a first time interval from the time when the first access point sends the phase abrupt value; The phase abrupt value is included in the tone signal; the time at which the second data point sends the target data frame after phase compensation is the second time, and the second time is the time when the second access
  • the point in time when a phase jump edge is detected is separated from the moment of the first time interval; the phase jump value is associated with the phase jump edge.
  • an embodiment of the present application provides an access point, where the access point is a second access point, and includes: a receiving unit, configured to receive a single tone signal sent by the first access point; a processing unit, Configured to determine a frequency difference between a first carrier and a second carrier according to the single tone signal; the first carrier is used by the first access point to send the single tone signal; and the second carrier is used for the The second access point receives the tone signal; the processing unit is further configured to perform phase compensation on the target data frame based on the frequency difference, so that the phase of the second carrier and the phase of the first carrier The difference between them is less than or equal to a first threshold; a sending unit is configured to send the target data frame after phase compensation through the second carrier.
  • the processing unit performs phase compensation on the target data frame through a frequency difference, so that a difference between a phase of the second carrier and a phase of the first carrier is less than or equal to a first threshold ; Therefore, the system bit error rate can be reduced.
  • the frequency difference is equal to a change amount of a phase difference of the tone signal in a unit time minus an original frequency of the tone signal
  • the mono signal is included in a first data frame, the first data frame further includes a target data frame, and the mono signal is in the first The time position in the data frame is earlier than the time position of the target data frame in the first data frame.
  • the receiving unit is further configured to receive an instruction sent by the first access point before receiving a mono signal sent by the first access point.
  • Information is used to indicate the following parameters of the mono signal: the original frequency of the mono signal and the time position of the mono signal.
  • a change amount of a phase difference of the single tone signal in a unit time is determined by a phase difference of multiple sampling times in a duration of the single tone signal. This implementation manner can reduce the measurement error of the change amount of the phase difference of the tone signal in a unit time.
  • the multiple sampling times include sampling times within a duration of the multiple tone signals. This implementation manner can reduce the measurement error of the change amount of the phase difference of the tone signal in a unit time.
  • the frequency difference is equal to an average value of a change amount of phase differences of each of the plurality of tone signals in a unit time minus an original value of the tone signals. frequency.
  • This implementation manner can further reduce the measurement error of the change amount of the phase difference of the tone signal in a unit time.
  • a change amount of a phase difference of the tone signal in a unit time is equal to a change amount of a phase difference of the tone signal in a first duration divided by Said first duration, said first duration being equal to a time interval between the duration of said two said mono signals and the duration of said two said mono signals being added.
  • This implementation manner can further reduce the measurement error of the change amount of the phase difference of the tone signal in a unit time.
  • the multiple sampling times within the duration of the mono signal include at least the start time of the mono signal and the end time of the mono signal. This implementation manner provides a preferred sampling time for sampling a single tone signal.
  • the processing unit is specifically configured to: at an initial time of the target data frame, perform phase compensation on the target data frame based on the frequency difference; or Phase-compensate the target data frame based on the frequency difference before the initial time of the target data frame; or perform target compensation on the target data frame based on the frequency difference after the initial time of the target data frame Phase compensation.
  • This implementation manner provides three preferred timings for phase compensation, and the second access point may choose to perform phase compensation on the transmission signal modulated with the target data frame at any of the foregoing preferred compensation timings.
  • the time when the sending unit sends the target data frame after phase compensation is the same as the time when the first access point sends the target data frame;
  • the time at which the first access point sends the target data frame is a first time, and the first time is a time at a first time interval from the time when the first access point sends a phase jump value;
  • the phase jump The value is included in the tone signal;
  • the time at which the sending unit sends the target data frame after phase compensation is the second time, and the second time is the edge of the phase change detected with the second access point.
  • Time is a moment away from the first time interval; the phase abrupt edge is associated with the phase abrupt value.
  • an embodiment of the present application provides an access point, where the access point is a first access point, and includes: a processing unit configured to generate a single tone signal, where the single tone signal is used to determine a first tone; The frequency difference between the carrier and the second carrier; the first carrier is used by the first access point to send the tone signal; the second carrier is used by the second access point to receive the tone signal; A unit configured to send the single tone signal to the second access point.
  • the generating unit is configured to generate a single tone signal, and the single tone signal is used to determine a frequency difference between the first carrier and the second carrier; the frequency difference is used by the second access point to phase the target data frame. Compensate so that the difference between the phase of the second carrier and the phase of the first carrier is less than or equal to the first threshold. Therefore, the system bit error rate can be reduced.
  • the frequency difference is equal to a change amount of a phase difference of the tone signal in a unit time minus an original frequency of the tone signal
  • the mono signal is included in a first data frame, the first data frame further includes a target data frame, and the mono signal is in the first The time position in the data frame is earlier than the time position of the target data frame in the first data frame.
  • the sending unit is further configured to send an instruction to the second access point before sending the tone signal to the second access point.
  • Information is used to indicate the following parameters of the tone signal; the original frequency of the tone signal and the time position of the tone signal.
  • a change amount of a phase difference of the single tone signal in a unit time is determined by a phase difference of multiple sampling times in a duration of the single tone signal. This implementation manner can reduce the measurement error of the change amount of the phase difference of the tone signal in a unit time.
  • the multiple sampling times include sampling times within a duration of the multiple tone signals. This implementation manner can reduce the measurement error of the change amount of the phase difference of the tone signal in a unit time.
  • the frequency difference is equal to an average value of a change amount of phase differences of a plurality of the tone signals in a unit time minus an original value of the tone signals. frequency.
  • This implementation manner can further reduce the measurement error of the change amount of the phase difference of the tone signal in a unit time.
  • a change amount of a phase difference of the tone signal in a unit time is equal to a change amount of a phase difference of the tone signal in a first duration divided by The first duration is equal to a time interval between the duration of the two tone signals and the duration of the two tone signals.
  • This implementation manner can further reduce the measurement error of the change amount of the phase difference of the tone signal in a unit time.
  • the multiple sampling times within the duration of the mono signal include at least: a start time of the mono signal and an end time of the mono signal.
  • This implementation manner provides a preferred sampling time for sampling a single tone signal.
  • a time when the second access point sends the target data frame after phase compensation is the same as a time when the sending unit sends the target data frame;
  • the moment when the sending unit sends the target data frame is a first moment, and the first moment is a moment away from the first time interval when the sending unit sends a phase abrupt value;
  • the phase abrupt value is included in the single Tone signal;
  • the time when the second access point sends the target data frame is the second time, and the second time is the first time from the time when the second access point detects a sudden phase change An interval of time; the phase abrupt value is associated with the phase abrupt edge.
  • an embodiment of the present application provides an access point, where the access point is a second access point, including a transceiver, a memory, and a processor coupled to the memory, and the transceiver and the memory And a processor coupled to the memory is connected to each other, wherein the transceiver is configured to perform a receiving or transmitting action, the memory is configured to store implementation code of the synchronization method described in the first aspect, and the processor is configured to call the The implementation code stored in the memory is the method for performing synchronization provided by the first aspect and any one of its various possible implementations.
  • an embodiment of the present application provides an access point, where the access point is a first access point, and includes a transceiver, a memory, and a processor coupled to the memory, and the transceiver and the memory. And a processor coupled to the memory is interconnected, wherein the transceiver is configured to perform a receiving or transmitting action, the memory is configured to store implementation code of the synchronization method described in the second aspect, and the processor is configured to call the The implementation code stored in the memory is the synchronization method provided by the second aspect and any one of its various possible implementation manners.
  • an embodiment of the present application provides a system, including: a first access point and a second access point; wherein the first access point is one of the fourth aspect and its various possible implementations.
  • an embodiment of the present application provides a computer-readable storage medium, where the computer-readable storage medium stores instructions, and when the instructions are executed by a processor, the processor is caused to execute the first aspect and A synchronization method provided by any one of its various possible implementations.
  • an embodiment of the present application provides a computer-readable storage medium, where the computer-readable storage medium stores instructions, and when the instructions are executed by a processor, the processor is caused to execute the second aspect and A synchronization method provided by any one of its various possible implementations.
  • an embodiment of the present application provides a computer program product.
  • the processor is caused to execute the first aspect and any one of various possible implementation manners provided by the processor. Synchronization method.
  • an embodiment of the present application provides a computer program product.
  • the program product is executed by a processor, the processor is caused to execute any one of the second aspect and its various possible implementation manners.
  • the provided synchronization method is provided.
  • FIG. 1a is a schematic diagram of a 64QAM constellation according to an embodiment of the present application.
  • FIG. 1b is a schematic diagram of principle of eliminating frequency difference between carriers of each access point through GPS Clock provided in an embodiment of the present application
  • 1c is a schematic diagram of a principle of eliminating a frequency difference between carriers of each access point through a clock distribution board according to an embodiment of the present application
  • FIG. 2a is a schematic diagram of a scenario in which an access point is connected by wire according to an embodiment of the present application
  • FIG. 2b is a schematic diagram of another scenario of wireless connection between access points according to an embodiment of the present application.
  • FIG. 3 is a schematic flowchart of a synchronization method according to an embodiment of the present application.
  • 4a is a schematic diagram of interaction between a first access point and a second access point according to an embodiment of the present application
  • 4b is another schematic diagram of interaction between a first access point and a second access point according to an embodiment of the present application
  • 4c is a schematic diagram of a phase difference of a single tone signal at a sampling time provided by an embodiment of the present application
  • 4d is a schematic diagram of a first access point and a second access point sending a target data frame synchronously according to an embodiment of the present application;
  • 4e is a schematic diagram of a sum of transmission and reception delays of an access point according to an embodiment of the present application.
  • 4f is a schematic diagram of a second access point performing phase compensation on a target data frame in a situation provided by an embodiment of the present application;
  • 4g is a schematic diagram of performing phase compensation on a target data frame by a second access point in another scenario provided by an embodiment of the present application;
  • FIG. 5 is a schematic structural diagram of an access point according to an embodiment of the present application.
  • FIG. 6 is a schematic structural diagram of another access point according to an embodiment of the present application.
  • FIG. 7 is a schematic structural diagram of still another access point according to an embodiment of the present application.
  • FIG. 8 is a schematic structural diagram of still another access point according to an embodiment of the present application.
  • FIG. 2a is a schematic diagram of an application scenario for synchronization using a Network MIMO technology according to an embodiment of the present application.
  • this scenario can include n access points (AP) and m mobile stations.
  • Each access point can be connected through a wire (such as Ethernet or fiber), and access point 1 is the main
  • the AP is taken as an example
  • the access point 2 is taken as an AP
  • the other (n-2) access points are taken as slave APs as an example.
  • Each access point is configured with at least one antenna
  • each mobile station is configured with at least one antenna.
  • the distance between each access point can be 1 meter, 10 meters, hundreds of meters, or several kilometers, which is not limited here.
  • each access point can also be connected wirelessly, as shown in FIG. 2b.
  • This scenario also includes n access points (AP) and m mobile stations.
  • Each access point is connected wirelessly. And take access point 1 as the main AP as an example, take access point 2 as the AP, and take the other (n-2) access points as slave APs as an example.
  • Each access point is configured with at least one antenna, and each mobile station is configured with at least one antenna.
  • the distance between each access point can be 1 meter, 10 meters, hundreds of meters, or several kilometers, which is not limited here.
  • each access point samples independent crystal sources. Because the crystals cannot be completely consistent, there is more or less slight frequency difference between the crystals, even if the frequency difference is small. It will cause phase rotation between access points. Due to phase rotation, the signals transmitted by n access points cooperate to accumulate phase errors. After the channel function, the relative The phase is constantly rotating, and the bit error rate rises. In the end, the mobile station cannot decode the received signal. The above-mentioned relative phase changes with time. The larger the frequency difference is, the faster the change amount of the phase difference is, and the higher the bit error rate is.
  • a schematic flowchart of the method as shown in FIG. 3, the method may include at least the following steps:
  • the first access point generates a tone signal.
  • a first access point is used as a master AP, and a second access point is used as a slave AP as an example.
  • a tone signal is a signal with a single frequency; for example, a tone signal may be a sinusoidal signal with a single frequency.
  • the tone signal may be included in the first data frame, and the first data frame may further include the target data frame.
  • the time position of the tone signal in the first data frame may be earlier than the time position of the target data frame in the first data frame.
  • the target data frame is data that the mobile station expects to receive from the access point, and the first data frame may further include some fields (such as L-STF, L-LTF, L-SIG, RL-SIG, HE-SIG- A and HE-STF, etc.), the mobile station can parse out the target data frame according to the above fields.
  • the first data frame may be an 802.11 frame.
  • the first access point sends a tone signal.
  • the second access point receives a single tone signal sent by the first access point.
  • the second access point may receive the indication information sent by the first access point; the indication information may include an indication tone
  • the following parameters of the signal the original frequency of the tone signal and the time position of the tone signal.
  • the single tone signal may be included in the first data frame, and the position of the single tone signal in the first data frame may be indicated by a number or a text.
  • the indication information may further include the following parameters: the number of phase mutation values in the mono signal, the duration of the mono signal, the time interval between the mono signal and the target data frame, and the like.
  • the second access point receiving the indication information sent by the first access point may include the following two implementation manners.
  • the first implementation manner Through the application layer interaction, the second access point receives the indication information sent by the first access point.
  • the first access point sends the instruction information encapsulated in the TCP / UDP packet to the second access point. After receiving the instruction information, the second access point will receive the instruction. The message confirmation message is sent to the first access point.
  • a second implementation manner Through MAC layer interaction, the second access point receives the instruction information sent by the first access point.
  • the first access point sends the instruction information encapsulated in the 802.11Action frame to the second access point.
  • the second access point receives the instruction information, on the one hand, the second access point The entry point does not respond.
  • the second access point may send an ACK frame to the first access point; or, the second access point may encapsulate the acknowledgement information of the received instruction information in an 802.11Action frame.
  • the second access point sends the 802.11Action frame encapsulated with the confirmation information to the first access point.
  • the indication information may also be encapsulated in a first data frame including a tone signal, and further, the first access point
  • the single-tone signal and the instruction information for indicating the single-tone signal may be sent to the second access point.
  • the second access point may determine the frequency difference between the first carrier and the second carrier according to the tone signal; the first carrier may be used by the first access point to send a tone signal; the second carrier may be used by the second access point to receive Mono signal.
  • the frequency difference may be equal to a change amount of a phase difference of a single tone signal in a unit time minus an original frequency of the single tone signal.
  • the first carrier can be expressed as:
  • the second carrier can be expressed as:
  • a single tone signal can be expressed as:
  • the first access point sends a transmission signal S a1 modulated with a tone signal to the second access point.
  • S a1 can be expressed as:
  • the transmitted signal S a1 may include the following frequency components: (W m + W a ) and (W m -W a ).
  • the second access point may demodulate the received transmission signal S a1 through the second carrier.
  • the demodulated signal may include the following frequency components: (W m + W a + W s ), (W m -W a + W s ), (W m + W a -W s ), and (W m -W a -W s ).
  • the second access point can filter the frequency component (W m + W s ) through a band-pass filter. Therefore, the demodulated signal will have only the following two frequency components: (W m + W a -W s ) And (W m -W a -W s ).
  • the second access point passes the demodulated signal containing only (W m + W a -W s ) and (W m -W a -W s ) through a low band-pass filter centered on Wa After filtering, only the frequency components remain in the signal: (W m + W a -W s ).
  • the frequency difference is equal to the amount of change in the phase difference of the tone signal in a unit time minus the original frequency of the tone signal.
  • the second access point may sample the imaginary part signal and the real part signal of the tone signal respectively.
  • the second access point can obtain the arc tangent result at that time by using the arc tangent function according to the real and imaginary parts of the mono signal at a sampling time.
  • the arc tangent result is used as the Phase difference.
  • the arc tangent result is less than 0, the arc tangent result is increased by 360 degrees.
  • the second access point can determine the phase difference of the monophonic signal at this time according to the real and imaginary parts of the monophonic signal at the sampling time by the arc tangent function at this time. degree.
  • the amount of change in the phase difference of the tone signal in a unit time is determined by the phase difference at multiple sampling times in the duration of the tone signal. Specifically, it may include: determining a change amount of a phase difference of a single tone signal in a unit time in the following three cases.
  • the first case if multiple sampling times within the duration of the mono signal are two sampling times, the change amount of the phase difference of the mono signal in unit time is: The difference between the phase difference and the phase difference of the tone signal at the second sampling time is divided by the value of the time interval between the two sampling times.
  • the second case if the multiple sampling times in the duration of the mono signal are at least three or more sampling times, the change amount of the phase difference of the mono signal in unit time is: the mono signal is in any two The difference between the phase differences at the sampling instants is divided by the value of the time interval between the two sampling instants.
  • the third case if the multiple sampling times in the duration of the mono signal are at least three or more sampling times, the change amount of the phase difference of the mono signal in unit time is: the mono signal is in any two The average value of the amount of change in phase difference per unit time determined at the time.
  • the frequency difference can be determined in the following two ways.
  • the multiple tone signals may be located in the same first data frame, or may be located in different first data frames.
  • the first method the frequency difference is equal to the average value of the change amounts of the phase differences of the multiple tone signals in a unit time minus the original frequency of the tone signals.
  • one of the mono signals is mono signal 1 and the other mono signal is mono signal 2.
  • the change amount 1 of the phase difference of the tone signal 1 in the unit time and the change amount 2 of the phase difference of the tone signal 2 in the unit time can be determined separately. Then, the change amount 1 and the change amount 2 are averaged. Value, the amount of change 3 can be obtained. Finally, the frequency difference is equal to the value of change 3 minus the original frequency of the tone signal.
  • the measurement error of the amount of change in the phase difference of the tone signal in a unit time can be reduced.
  • the second method the amount of change in the phase difference of the tone signal in a unit time is equal to the amount of change in the phase difference of the tone signal in the first duration divided by the first duration, and the first duration is equal to the two tones The time interval between the duration of the signal and the duration of the two tone signals is added.
  • one of the mono signals is mono signal 3
  • the other mono signal is mono signal 4.
  • the duration of the mono signal 3 and the mono signal 4 is 4us
  • the frequency is 250Khz
  • the time interval between the mono signal 3 and the mono signal 4 is 480us.
  • phase difference of the mono signal 3 at the initial time is 17 degrees
  • the phase difference of the mono signal 3 at the termination time is 37 degrees
  • the duration of the mono signal 3 includes a 360-degree phase change
  • the mono signal 4 The phase difference at the initial time is 277 degrees
  • the phase difference of the mono signal 4 at the termination time is 296 degrees
  • the duration of the mono signal 4 includes a 360-degree phase change.
  • the number of phase rotations of 360 degrees during the duration of the tone signal 3, the number of phase rotations of 360 degrees during the duration of the tone signal 4, and the phase rotation of 360 degrees within the aforementioned time interval of 480us are combined.
  • the second access point can determine that the change amount of the phase difference of the single tone signal in a unit time is: 94.994 (degrees / us) (that is, 46357 degrees / 488us).
  • the frequency difference S1 is equal to the amount of change in the phase difference of the tone signal in a unit time minus the original frequency of the tone signal.
  • the change amount of the phase difference of the single tone signal in unit time is 4.994 degrees / us.
  • the measurement error of the amount of change in the phase difference of the tone signal in a unit time can be reduced.
  • the multiple sampling times within the duration of the mono signal include at least the start time of the mono signal and the end time of the mono signal.
  • the sampling time in this implementation manner is a preferred sampling time. With this implementation manner, the measurement error of the change amount of the phase difference of the single-tone signal in a unit time is small.
  • the second access point may The single tone signal in the received second data frame determines the frequency difference between the first carrier and the second carrier.
  • the second access point performs phase compensation on the target data frame based on the frequency difference, so that the difference between the phase of the second carrier and the phase of the first carrier is less than or equal to the first threshold.
  • the target data frame is an encoded target data frame.
  • the phase of the first carrier is the phase of the first transmitted signal, and the phase of the second carrier is the phase of the second transmitted signal; wherein the first transmitted signal is a signal generated by the target data frame modulated on the first carrier, and the second transmitted
  • the signal is a signal generated by modulating the target data frame after phase compensation on the second carrier.
  • the difference is a changing value, and the difference is different at different times.
  • the difference between the phase of the second carrier and the phase of the first carrier is less than or equal to the first threshold, which is equivalent to the difference between the phase of the first transmitted signal and the phase of the second transmitted signal.
  • First threshold is equivalent to the difference between the phase of the first transmitted signal and the phase of the second transmitted signal.
  • the second access point may perform phase compensation on the target data frame based on the frequency difference at the following three times.
  • the second access point performs phase compensation on the target data frame based on the frequency difference
  • the second access point performs phase compensation on the target data frame based on the frequency difference
  • the second access point performs phase compensation on the target data frame based on the frequency difference
  • the second access point performs phase compensation on the target data frame based on the frequency difference.
  • the second access point may perform phase compensation on the target data frame in the following two ways.
  • the first method if the change amount of the phase difference of the single tone signal within a unit time is small, the second access point controls each sampling point in a single symbol in the target data frame for the duration of the target data frame. Use the same compensation value for phase compensation.
  • phase difference of the mono signal at the time of 1.05us is -30 degrees (that is, the phase of the second carrier is 30 degrees ahead of the phase of the first carrier).
  • the amount of change in phase difference within time is 0.0125 degrees / us (the master AP will exceed the slave AP1 by 0.0125 degrees per 1us), then during the duration of the transmission signal modulated with the target data frame, the second access point performs the target data frame Each sampling point within a single symbol in the phase compensation is performed using the same compensation value.
  • the second method if the change amount of the phase difference of the single-tone signal in unit time is small, the second access point performs sampling on each sampling point in a single symbol in the target data frame for the duration of the target data frame. Different compensation values are used for phase compensation.
  • phase difference of the single-tone signal at the time of 1.10us is 85 degrees (that is, the phase of the second carrier is 85 degrees behind the phase of the first carrier).
  • the amount of change in phase difference is 0.551 degrees / us (the master AP will exceed the slave AP1 by 0.551 degrees per 1us), and the second access point uses different compensation values for each sampling point within a single symbol in the modulated target data frame Perform phase compensation.
  • phase compensation provides different phase compensation schemes for different scenarios, which can reduce the computational complexity and improve the accuracy of phase compensation.
  • SNR signal-to-noise ratio
  • the first access point sends a target data frame to the terminal.
  • the target data frame is modulated on a first carrier to generate a first transmission signal.
  • the first access point sends the target data frame by sending a first transmission signal.
  • the second access point sends the phase-compensated target data frame to the terminal through the second carrier.
  • the target data frame after phase compensation is modulated on a second carrier to generate a second transmission signal.
  • the second access point sends the target data frame after the phase compensation described above by sending a second transmission signal.
  • time when the second access point sends the target data frame after phase compensation is the same as the time when the first access point sends the target data frame.
  • the time at which the first access point sends the target data frame is the first time, and the first time is the time at a first interval from the time when the first access point sends the phase jump value; the phase jump value is included in the tone signal.
  • the time when the second access point sends the phase-compensated target data frame is the second time, and the second time is the time from the first time interval when the phase transition edge is detected by the second access point; the phase transition edge and the phase transition Value association.
  • the number of phase mutation values in a single tone signal may be single or multiple.
  • the time of the target data frame may be the initial time of the target data frame or the end time of the target data frame; the time of the target data frame after the phase modulation may be the initial time of the target data frame after the phase modulation or the target of the phase modulation The end time of the data frame.
  • the first time is the initial time of the target data frame
  • the second time is the initial time of the target data frame after the phase compensation is taken as an example
  • the first access point is used as an example
  • the second access point is used as a slave.
  • the time at which the master AP sends a phase jump value is 38us from the time at which the master AP sends the target data frame; a phase jump edge is detected at time 1.05us from AP1, and the phase jump edge is considered from AP1 to be phase compensated.
  • the time interval of the initial time of the target data frame is 38us, so the time of sending the target data frame after phase compensation from AP1 is 39.05us.
  • the phase transition edge is detected from AP2 at 1.10us, and the time interval from the initial moment of the target data frame to be phase compensated is considered to be 38us from AP2. Therefore, the time of the target data frame after phase compensation is sent from AP2 For 39.10us. Assume that the sum of transmission and reception delays from AP1 is 1.35us, and the sum of transmission and reception delays from AP2 is 1.20us. If the sum of transmission and reception delays from AP1 is considered, the phase compensation from AP1 needs to be transmitted at 37.70us For the target data frame, if the transmission and reception delay sums are considered from AP2, the AP2 needs to send the phase-compensated target data frame at 37.90us.
  • the slave AP can determine the sum of the transmission and reception delays in a spontaneous and self-receiving manner.
  • the sum of the transmission and reception delays of the slave AP is (S1-R1).
  • FIG. 5 exemplarily illustrates an access point, where the access point 50 is a second access point in the method embodiment of FIG. 3.
  • the access point 50 may include a receiving unit 501, a processing unit 502, and a sending unit 503.
  • the receiving unit 501 is configured to receive a mono signal sent by a first access point.
  • the processing unit 502 is configured to determine the frequency difference between the first carrier and the second carrier according to the tone signal; the first carrier is used by the first access point to send a first data frame; the second carrier is used by the second access point to receive the first data frame; A data frame.
  • the processing unit 502 is further configured to perform phase compensation on the target data frame based on the frequency difference, so that the difference between the phase of the second carrier and the phase of the first carrier is less than or equal to the first threshold.
  • the sending unit 503 is configured to send the target data frame after phase compensation through the second carrier.
  • the receiving unit 501 may be further configured to receive instruction information sent by the first access point before receiving the mono signal sent by the first access point; the instruction information may include the following parameters for indicating the mono signal: The original frequency and the time position of the tone signal.
  • the mono signal is included in the first data frame, and the first data frame may further include the target data frame.
  • the time position of the mono signal in the first data frame may be earlier than the target data frame in the first data frame. Time position.
  • the amount of change in the phase difference of a single tone signal in a unit time is determined by the phase differences of multiple sampling moments in the duration of the single tone signal.
  • the plurality of sampling times include sampling times within a duration of a plurality of tone signals.
  • the above-mentioned frequency difference is equal to the average value of the change amounts of the phase differences of the plurality of tone signals in a unit time minus the original frequency of the tone signals.
  • the amount of change in the phase difference of the tone signal in a unit time is equal to the amount of change in the phase difference of the tone signal in the first duration divided by the first duration.
  • the first duration is equal to the duration of the two tone signals. Add to the time interval between the durations of the two said tone signals.
  • the multiple sampling times within the duration of the mono signal include at least: the start time of the mono signal and the end time of the mono signal.
  • the processing unit 502 is specifically configured to:
  • phase compensation is performed on the target data frame based on the frequency difference.
  • the time at which the sending unit sends the target data frame after phase compensation is the same as the time at which the first access point sends the target data frame
  • the time at which the first access point sends the target data frame is the first time, and the first time is the time at a first interval from the time when the first access point sends the phase jump value; the phase jump value is included in the tone signal;
  • the time at which the sending unit 503 sends the phase-compensated target data frame is the second time, and the second time is the time from the first time interval when the second access point detects a sudden phase change; Value association.
  • the access point 50 may have a There are more or fewer parts, two or more parts can be combined, or they can be implemented with different configurations of parts.
  • FIG. 6 exemplarily illustrates an access point.
  • the access point 60 is the first access point in the method embodiment of FIG. 3.
  • the access point 60 may include a processing unit 601 and a sending unit 602.
  • a processing unit 601 is configured to generate a single tone signal, where the single tone signal is used to determine a frequency difference between a first carrier and a second carrier; the first carrier is used by the first access point to send the single tone signal ; The second carrier is used by a second access point to receive the tone signal.
  • the sending unit 602 is configured to send the tone signal to the second access point.
  • the sending unit 602 is further configured to send instruction information to the second access point before sending the tone signal to the second access point; the instruction information is used to indicate the following of the tone signal Parameters; the original frequency of the tone signal and the time position of the tone signal.
  • the mono signal is included in the first data frame, and the first data frame further includes the target data frame.
  • the time position of the mono signal in the first data frame is earlier than the time position of the target data frame in the first data frame. .
  • the amount of change in the phase difference of the single tone signal in a unit time is determined by the phase difference at a plurality of sampling times within the duration of the single tone signal.
  • the multiple sampling times include sampling times within the duration of the plurality of tone signals.
  • the above-mentioned frequency difference is equal to the average value of the change amounts of the phase differences of the plurality of tone signals in a unit time minus the original frequency of the tone signals.
  • the amount of change in the phase difference of the single tone signal in a unit time is equal to the amount of change in the phase difference of the single tone signal in the first duration divided by the first duration.
  • the first duration is equal to the duration of the two tone signals and two The time intervals between the durations of the single tone signals are added.
  • the multiple sampling times within the duration of the mono signal include at least: the start time of the mono signal and the end time of the mono signal.
  • the time when the second access point sends the target data frame after phase compensation is the same as the time when the sending unit 602 sends the target data frame;
  • the time when the sending unit 602 sends the target data frame is the first time, and the first time is the time that is away from the first time interval when the sending unit 602 sends the phase abrupt value; the phase abrupt value is included in the tone signal;
  • the time when the second access point sends the target data frame is the second time, and the second time is the time from the first time interval when the phase jump edge is detected by the second access point; the phase jump value is associated with the phase jump edge .
  • the access point 60 for specific technical features related to the access point 60, reference may be made to the description in the method embodiment of FIG. 3, and the access point 60 is only an example provided by the embodiment of the present application, and the access point 60 may There are more or fewer parts, two or more parts can be combined, or they can be implemented with different configurations of parts.
  • FIG. 7 exemplarily illustrates an access point, where the access point 70 is the second access point in the method embodiment of FIG. 3.
  • the access point 70 may include a processor 701, a memory 702, and a transceiver 703.
  • the transceiver 703, the memory 702, and the processor 701 coupled to the memory 702 are mutually connected.
  • the memory 702 may be a permanent memory, such as a flash memory and a hard disk drive.
  • the memory 702 is used to store a synchronization code, which can be accessed and called by the processor 701.
  • the transceiver 703 is configured to receive a single tone signal sent by the first access point.
  • the processor 701 is configured to access and call the foregoing synchronization code stored in the memory 702, and execute the following steps:
  • Step 1 The frequency difference between the first carrier and the second carrier may be determined according to the tone signal sent by the first access point received by the transceiver 703.
  • the first carrier may be used by the access point 70 to send the first data frame.
  • Two carriers can be used for the access point 70 to receive the first data frame.
  • Step 2 Perform phase compensation on the target data frame based on the frequency difference, so that the difference between the phase of the second carrier and the phase of the first carrier is less than or equal to the first threshold.
  • the transceiver 703 is further configured to send the phase-compensated target data frame through the second carrier.
  • the access point 70 may have a There are more or fewer parts, two or more parts can be combined, or they can be implemented with different configurations of parts.
  • FIG. 8 exemplarily illustrates an access point.
  • the access point 80 is the first access point in the method embodiment of FIG. 3.
  • the access point 80 may include: a processor 801, a memory 802, and a transceiver 803.
  • the transceiver 803, the memory 802, and the processor 801 coupled to the memory 802 are mutually connected.
  • the memory 802 may be a permanent memory, such as a flash memory and a hard disk drive.
  • the memory 802 is used to store a synchronization code, which can be accessed and called by the processor 801.
  • a processor 801 configured to access and call the synchronization code stored in the memory 802, and generate a single tone signal, where the single tone signal is used to determine a frequency difference between the first carrier and the second carrier; the first carrier is used for the first access The point sends a single tone signal; the second carrier is used by the second access point to receive the single tone signal.
  • the transceiver 803 is configured to send a single tone signal to the second access point.
  • the transceiver 803 is further configured to send a target data frame.
  • the above-mentioned access point may also include only a processor.
  • the memory for storing the program is located outside the access point, and the processor is connected to the memory through a circuit / wire for reading and executing the program stored in the memory.
  • the processor may be a central processing unit (Central Processing Unit), a network processor (Network Processor), or a combination of CPU and NP.
  • Central Processing Unit Central Processing Unit
  • Network Processor Network Processor
  • the processor may further include a hardware chip.
  • the above-mentioned hardware chip may be an application-specific integrated circuit (ASIC), a programmable logic device (Programmable Logic Device, PLD), or a combination thereof.
  • the PLD may be a complex programmable logic device (Complex Programmable Logic Device, CPLD), a field programmable logic gate array (Field-programmable Gate Array, FPGA), a universal array logic (Generic Array Logic, GAL), or any combination thereof.
  • the memory may include volatile memory (for example, Random-Access Memory, RAM); the memory may also include non-volatile memory (for example, Flash memory) Hard disk (Hard Disk Drive, HDD) or solid state drive (Solid-State Drive, SSD); the storage may also include a combination of the above types of storage.
  • volatile memory for example, Random-Access Memory, RAM
  • non-volatile memory for example, Flash memory
  • Hard disk Hard Disk Drive, HDD
  • SSD solid state drive
  • the storage may also include a combination of the above types of storage.
  • An embodiment of the present application further provides a computer storage medium storing a computer program, where the computer program is used to execute the synchronization method provided by the foregoing embodiment.
  • the embodiment of the present application further provides a computer program product containing instructions, which when executed on a computer, causes the computer to execute the synchronization method provided by the foregoing embodiment.
  • this application may provide a method, a system, or a computer program product. Therefore, this application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Moreover, this application may take the form of a computer program product implemented 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.
  • computer-usable storage media including, but not limited to, disk storage, CD-ROM, optical storage, etc.
  • These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to work in a specific manner such that the instructions stored in the computer-readable memory produce a manufactured article including an instruction device, the instructions
  • the device implements the functions specified in one or more flowcharts and / or one or more blocks of the block diagram.
  • These computer program instructions can also be loaded onto a computer or other programmable data processing device, so that a series of steps can be performed on the computer or other programmable device to produce a computer-implemented process, which can be executed on the computer or other programmable device.
  • the instructions provide steps for implementing the functions specified in one or more flowcharts and / or one or more blocks of the block diagrams.

Abstract

本申请实施例提供一种同步方法及接入点，其中，方法包括：第二接入点接收第一接入点发送的单音信号；所述第二接入点根据所述单音信号确定第一载波与第二载波的频差；所述第一载波用于所述第一接入点发送所述单音信号；所述第二载波用于所述第二接入点接收所述单音信号；所述第二接入点基于所述频差对目标数据帧进行相位补偿，以使得所述第二载波的相位与所述第一载波的相位之间的差值小于或等于第一阈值；所述第二接入点通过所述第二载波发送相位补偿后的所述目标数据帧。采用本申请实施例，可降低系统误码率。

Description

一种同步方法及接入点 技术领域
本申请涉及通信技术领域，尤其涉及一种同步方法及接入点。
背景技术
在一个分布式Network MIMO场景中，在发送端，由于各个接入点采用独立的晶振源。由于无法保证晶振完全一致，晶振间或多或少存在微小的频差，比如10Mhz的晶振可存在1PPM(parts-per-million)的差异。当经过射频锁相环(Radio Frequency Phase Locked Loop，RF PLL)生成射频载频(5G)时,就会导致接入点间存在约5Khz的频差,从而形成了接入点间的相位旋转。由于相位旋转，由多个接入点协作进行发射的信号存在相位误差的累积，经过信道作用之后，接收端接收到的信号的相对相位在不断旋转，误码率上升，直至接收端无法对接收到的信号进行解码，上述相对相位是随时间变化的，载频差越大，相位差的变化量越快，误码率越高。其中，导致误码率较高的原因如下，如图1a所示，如果发送端的多个接入点间存在频差，接收端的星座图映射就不可能映射到预定的位置，而且映射位置还在随着时间不停地变化，因而导致误码率上升。
在发送端，为了减小接入点间的频差，如图1b所示，各接入点配置GPS时钟模块接收外部GPS Clock，从而实现接入点同源晶振的目的，各接入点间进而不存在频差。在室内场景(火车站和机场)下，GPS信号微弱，甚至没有，因此该方案只能在室外环境中适用。
另外，在发送端，为了减小接入点间的频差，如图1c所示，通过外部配置的时钟板，利用时钟线将该时钟板的时钟信号引到各个接入点上作为参考时钟，从而各个接入点的参考时钟都是该时钟板输出的同源时钟信号，进而实现了接入点同源晶振的目的，各接入点间进而不存在频差。该方案需要额外配置时钟板，部署时钟线，带来额外的成本和时间开销。
发明内容
本申请实施例提供了一种同步方法及接入点，可降低系统误码率。
第一方面，本申请实施例提供了一种同步方法，包括：第二接入点接收第一接入点发送的单音信号；所述第二接入点根据所述单音信号确定第一载波与第二载波的频差；所述第一载波用于所述第一接入点发送所述单音信号；所述第二载波用于所述第二接入点接收所述单音信号；所述第二接入点基于所述频差对目标数据帧进行相位补偿，以使得所述第二载波的相位与所述第一载波的相位之间的差值小于或等于第一阈值；所述第二接入点通过所述第二载波发送相位补偿后的所述目标数据帧。
通过第一方面提供的技术方案，第二接入点通过频差对目标数据帧进行相位补偿，以使得所述第二载波的相位与所述第一载波的相位之间的差值小于或等于第一阈值；因而，可降低系统误码率。
结合上述第一方面，在一种可能的实现方式中，所述频差等于所述单音信号在单位时间内的相位差的变化量减去所述单音信号的原始频率；
结合上述第一方面，在一种可能的实现方式中，所述单音信号包括在第一数据帧中，所述第一数据帧还包括目标数据帧，所述单音信号在所述第一数据帧中的时间位置早于所述目标数据帧在所述第一数据帧中的时间位置。
结合上述第一方面，在一种可能的实现方式中，所述第二接入点接收第一接入点发送的单音信号之前，还包括：所述第二接入点接收所述第一接入点发送的指示信息；所述指示信息用于指示所述单音信号的以下参数：所述单音信号的原始频率及所述单音信号的时间位置。
结合上述第一方面，在一种可能的实现方式中，所述单音信号在单位时间内的相位差的变化量由所述单音信号的持续时间内的多个采样时刻的相位差确定。该实现方式，可降低单音信号在单位时间内的相位差的变化量的测量误差。
结合上述第一方面，在一种可能的实现方式中，所述多个采样时刻包括在多个所述单音信号的持续时间内的采样时刻。该实现方式，可降低单音信号在单位时间内的相位差的变化量的测量误差。
结合上述第一方面，在一种可能的实现方式中，所述频差等于多个所述单音信号各自在单位时间内的相位差的变化量的平均值减去所述单音信号的原始频率。该实现方式，可进一步降低单音信号在单位时间内的相位差的变化量的测量误差。
结合上述第一方面，在一种可能的实现方式中，所述单音信号在单位时间内的相位差的变化量等于第一持续时间内所述单音信号的相位差的变化量除以所述第一持续时间，所述第一持续时间等于所述两个所述单音信号的持续时间与所述两个所述单音信号的持续时间之间的时间间隔相加。该实现方式，可进一步降低单音信号在单位时间内的相位差的变化量的测量误差。
结合上述第一方面，在一种可能的实现方式中，所述单音信号的持续时间内的多个采样时刻至少包括：所述单音信号的开始时刻和所述单音信号的结束时刻。该实现方式提供了一种优选的采样时刻对单音信号进行采样。
结合上述第一方面，在一种可能的实现方式中，所述第二接入点基于所述频差对目标数据帧进行相位补偿，具体为：在所述目标数据帧的初始时刻，所述第二接入点基于所述频差对目标数据帧进行相位补偿；或者在所述目标数据帧的初始时刻之前，所述第二接入点基于所述频差对目标数据帧进行相位补偿；或者在所述目标数据帧的初始时刻之后，所述第二接入点基于所述频差对目标数据帧进行相位补偿。该实现方式，提供了三个优选的相位补偿时刻，第二接入点可选择在上述任一优选的补偿时刻，对调制有所述目标数据帧的发射信号进行相位补偿。
结合上述第一方面，在一种可能的实现方式中，第二接入点对目标数据帧进行相位补偿可包括以下两种方式。第一种方式：如果单音信号在单位时间内的相位差的变化量较小，则在目标数据帧的持续时间内，第二接入点采用同一个补偿值对目标数据帧进行相位补偿。第二种方式：如果单音信号在单位时间内的相位差的变化量较小，则在目标数据帧的持续时间内，第二接入点在不同的采样时刻采用不同的补偿值对目标数据帧进行相位补偿。该实现方式，针对不同的场景，提供了不同的相位补偿方案，可降低运算复杂度，提高相位 补偿的准确度。
结合上述第一方面，在一种可能的实现方式中，所述第二接入点发送相位补偿后的所述目标数据帧的时刻和所述第一接入点发送所述目标数据帧的时刻相同；所述第一接入点发送所述目标数据帧的时刻为第一时刻，所述第一时刻为与所述第一接入点发送相位突变值时相距第一时间间隔的时刻；所述相位突变值包括在所述单音信号中；所述第二接入点发送所述目标数据帧的时刻为第二时刻，所述第二时刻为与所述第二接入点检测到相位突变沿时相距所述第一时间间隔的时刻；所述相位突变沿与所述相位突变值关联。
第二方面，本申请实施例提供了一种同步方法，包括：第一接入点生成单音信号，所述单音信号用于确定第一载波与第二载波的频差；所述第一载波用于所述第一接入点发送所述单音信号；所述第二载波用于第二接入点接收所述单音信号；所述第一接入点向所述第二接入点发送所述单音信号。
通过第二方面提供的技术方案，第一接入点生成单音信号，单音信号用于确定第一载波与第二载波的频差；频差用于第二接入点对目标数据帧进行相位补偿，以使得第二载波的相位与第一载波的相位之间的差值小于或等于第一阈值。因而，可降低系统误码率。
结合上述第二方面，在一种可能的实现方式中，所述频差等于所述单音信号在单位时间内的相位差的变化量减去所述单音信号的原始频率；
结合上述第二方面，在一种可能的实现方式中，所述单音信号包括在第一数据帧中，所述第一数据帧还包括所述目标数据帧，所述单音信号在所述第一数据帧中的时间位置早于所述目标数据帧在所述第一数据帧中的时间位置。
结合上述第二方面，在一种可能的实现方式中，所述第一接入点向第二接入点发送单音信号之前，还包括：所述第一接入点向所述第二接入点发送指示信息；所述指示信息用于指示所述单音信号的以下参数：所述单音信号的原始频率及所述单音信号的时间位置。
结合上述第二方面，在一种可能的实现方式中，所述单音信号在单位时间内的相位差的变化量由所述单音信号的持续时间内的多个采样时刻的相位差确定。该实现方式，可降低单音信号在单位时间内的相位差的变化量的测量误差。
结合上述第二方面，在一种可能的实现方式中，所述多个采样时刻包括在多个所述单音信号的持续时间内的采样时刻。该实现方式，可降低单音信号在单位时间内的相位差的变化量的测量误差。
结合上述第二方面，在一种可能的实现方式中，所述频差等于多个所述单音信号各自在单位时间内的相位差的变化量的平均值减去所述单音信号的原始频率。该实现方式，可进一步降低单音信号在单位时间内的相位差的变化量的测量误差。
结合上述第二方面，在一种可能的实现方式中，所述单音信号在单位时间内的相位差的变化量等于第一持续时间内所述单音信号的相位差的变化量除以所述第一持续时间，所述第一持续时间等于所述两个所述单音信号的持续时间与所述两个所述单音信号的持续时间之间的时间间隔相加。该实现方式，可进一步降低单音信号在单位时间内的相位差的变化量的测量误差。
结合上述第二方面，在一种可能的实现方式中，所述单音信号的持续时间内的多个采 样时刻至少包括：所述单音信号的开始时刻和所述单音信号的结束时刻。该实现方式提供了一种优选的采样时刻对单音信号进行采样。
结合上述第二方面，在一种可能的实现方式中，处理单元对调制有目标数据帧的发射信号进行相位补偿可包括以下两种方式。第一种方式：如果单音信号在单位时间内的相位差的变化量较小，则在调制有目标数据帧的发射信号的持续时间内，处理单元采用同一个补偿值对调制有目标数据帧的发射信号进行相位补偿。第二种方式：如果单音信号在单位时间内的相位差的变化量较小，则在调制有目标数据帧的发射信号的持续时间内，处理单元在不同的采样时刻采用不同的补偿值对调制有目标数据帧的发射信号进行相位补偿。该实现方式，针对不同的场景，提供了不同的相位补偿方案，可降低运算复杂度，提高相位补偿的准确度。
结合上述第二方面，在一种可能的实现方式中，所述第二接入点发送相位补偿后的所述目标数据帧的时刻和所述第一接入点发送所述目标数据帧的时刻相同；所述第一接入点发送所述目标数据帧的时刻为第一时刻，所述第一时刻为与所述第一接入点发送相位突变值时相距第一时间间隔的时刻；所述相位突变值包括在所述单音信号中；所述第二接入点发送相位补偿后的所述目标数据帧的时刻为第二时刻，所述第二时刻为与所述第二接入点检测到相位突变沿时相距所述第一时间间隔的时刻；所述相位突变值与所述相位突变沿关联。
第三方面，本申请实施例提供了一种接入点，所述接入点为第二接入点，包括：接收单元，用于接收第一接入点发送的单音信号；处理单元，用于根据所述单音信号确定第一载波与第二载波的频差；所述第一载波用于所述第一接入点发送所述单音信号；所述第二载波用于所述第二接入点接收所述单音信号；所述处理单元，还用于基于所述频差对目标数据帧进行相位补偿，以使得所述第二载波的相位与所述第一载波的相位之间的差值小于或等于第一阈值；发送单元，用于通过所述第二载波发送相位补偿后的所述目标数据帧。
通过第三方面提供的技术方案，处理单元通过频差对目标数据帧进行相位补偿，以使得所述第二载波的相位与所述第一载波的相位之间的差值小于或等于第一阈值；因而，可降低系统误码率。
结合上述第三方面，在一种可能的实现方式中，所述频差等于所述单音信号在单位时间内的相位差的变化量减去所述单音信号的原始频率；
结合上述第三方面，在一种可能的实现方式中，所述单音信号包括在第一数据帧中，所述第一数据帧还包括目标数据帧，所述单音信号在所述第一数据帧中的时间位置早于所述目标数据帧在所述第一数据帧中的时间位置。
结合上述第三方面，在一种可能的实现方式中，所述接收单元，还用于在接收所述第一接入点发送的单音信号之前，接收所述第一接入点发送的指示信息；所述指示信息用于指示所述单音信号的以下参数：所述单音信号的原始频率及所述单音信号的时间位置。
结合上述第三方面，在一种可能的实现方式中，所述单音信号在单位时间内相位差的变化量由所述单音信号的持续时间内的多个采样时刻的相位差确定。该实现方式，可降低单音信号在单位时间内的相位差的变化量的测量误差。
结合上述第三方面，在一种可能的实现方式中，所述多个采样时刻包括在多个所述单音信号的持续时间内的采样时刻。该实现方式，可降低单音信号在单位时间内的相位差的变化量的测量误差。
结合上述第三方面，在一种可能的实现方式中，所述频差等于多个所述单音信号各自在单位时间内的相位差的变化量的平均值减去所述单音信号的原始频率。该实现方式，可进一步降低单音信号在单位时间内的相位差的变化量的测量误差。
结合上述第三方面，在一种可能的实现方式中，所述单音信号在单位时间内的相位差的变化量等于第一持续时间内所述单音信号的相位差的变化量除以所述第一持续时间，所述第一持续时间等于所述两个所述单音信号的持续时间与所述两个所述单音信号的持续时间之间的时间间隔相加。该实现方式，可进一步降低单音信号在单位时间内的相位差的变化量的测量误差。
结合上述第三方面，在一种可能的实现方式中，所述单音信号的持续时间内的多个采样时刻至少包括；所述单音信号的开始时刻和所述单音信号的结束时刻。该实现方式提供了一种优选的采样时刻对单音信号进行采样。
结合上述第三方面，在一种可能的实现方式中，所述处理单元，具体用于：在所述目标数据帧的初始时刻，基于所述频差对所述目标数据帧进行相位补偿；或者在所述目标数据帧的初始时刻之前，基于所述频差对所述目标数据帧进行相位补偿；或者在所述目标数据帧的初始时刻之后，基于所述频差对所述目标数据帧进行相位补偿。该实现方式，提供了三个优选的相位补偿时刻，第二接入点可选择在上述任一优选的补偿时刻，对调制有所述目标数据帧的发射信号进行相位补偿。
结合上述第三方面，在一种可能的实现方式中，所述发送单元发送相位补偿后的所述目标数据帧的时刻和所述第一接入点发送所述目标数据帧的时刻相同；所述第一接入点发送所述目标数据帧的时刻为第一时刻，所述第一时刻为与所述第一接入点发送相位突变值时相距第一时间间隔的时刻；所述相位突变值包括在所述单音信号中；所述发送单元发送相位补偿后的所述目标数据帧的时刻为第二时刻，所述第二时刻为与所述第二接入点检测到相位突变沿时相距所述第一时间间隔的时刻；所述相位突变沿与所述相位突变值关联。
第四方面，本申请实施例提供了一种接入点，所述接入点为第一接入点，包括：处理单元，用于生成单音信号，所述单音信号用于确定第一载波与第二载波的频差；所述第一载波用于所述第一接入点发送所述单音信号；所述第二载波用于第二接入点接收所述单音信号；发送单元，用于向所述第二接入点发送所述单音信号。
通过第四方面提供的技术方案，生成单元用于生成单音信号，单音信号用于确定第一载波与第二载波的频差；频差用于第二接入点对目标数据帧进行相位补偿，以使得第二载波的相位与第一载波的相位之间的差值小于或等于第一阈值。因而，可降低系统误码率。
结合上述第四方面，在一种可能的实现方式中，所述频差等于所述单音信号在单位时间内的相位差的变化量减去所述单音信号的原始频率；
结合上述第四方面，在一种可能的实现方式中，所述单音信号包括在第一数据帧中，所述第一数据帧还包括目标数据帧，所述单音信号在所述第一数据帧中的时间位置早于所 述目标数据帧在所述第一数据帧中的时间位置。
结合上述第四方面，在一种可能的实现方式中，所述发送单元，还用于在向所述第二接入点发送所述单音信号之前，向所述第二接入点发送指示信息；所述指示信息用于指示所述单音信号的以下参数；所述单音信号的原始频率及所述单音信号的时间位置。
结合上述第四方面，在一种可能的实现方式中，所述单音信号在单位时间内的相位差的变化量由所述单音信号的持续时间内的多个采样时刻的相位差确定。该实现方式，可降低单音信号在单位时间内的相位差的变化量的测量误差。
结合上述第四方面，在一种可能的实现方式中，所述多个采样时刻包括在多个所述单音信号的持续时间内的采样时刻。该实现方式，可降低单音信号在单位时间内的相位差的变化量的测量误差。
结合上述第四方面，在一种可能的实现方式中，所述频差等于多个所述单音信号各自在单位时间内的相位差的变化量的平均值减去所述单音信号的原始频率。该实现方式，可进一步降低单音信号在单位时间内的相位差的变化量的测量误差。
结合上述第四方面，在一种可能的实现方式中，所述单音信号在单位时间内的相位差的变化量等于第一持续时间内所述单音信号的相位差的变化量除以所述第一持续时间，所述第一持续时间等于所述两个单音信号的持续时间与所述两个所述单音信号的持续时间之间的时间间隔相加。该实现方式，可进一步降低单音信号在单位时间内的相位差的变化量的测量误差。
结合上述第四方面，在一种可能的实现方式中，所述单音信号的持续时间内的多个采样时刻至少包括：所述单音信号的开始时刻和所述单音信号的结束时刻。该实现方式提供了一种优选的采样时刻对单音信号进行采样。
结合上述第四方面，在一种可能的实现方式中，所述第二接入点发送相位补偿后的所述目标数据帧的时刻和所述发送单元发送所述目标数据帧的时刻相同；所述发送单元发送所述目标数据帧的时刻为第一时刻，所述第一时刻为与所述发送单元发送相位突变值时相距第一时间间隔的时刻；所述相位突变值包括在所述单音信号中；所述第二接入点发送所述目标数据帧的时刻为第二时刻，所述第二时刻为与所述第二接入点检测到相位突变沿时相距所述第一时间间隔的时刻；所述相位突变值与所述相位突变沿关联。
第五方面，本申请实施例提供了一种接入点，所述接入点为第二接入点，包括：收发器、存储器以及与所述存储器耦合的处理器，所述收发器、存储器以及与所述存储器耦合的处理器相互连接，其中，所述收发器用于执行接收或发送动作，所述存储器用于存储第一方面描述的同步方法的实现代码，所述处理器用于调用所述存储器中存储的实现代码，即执行第一方面及其各种可能的实现方式中的任意一种所提供的同步方法。
第六方面，本申请实施例提供了一种接入点，所述接入点为第一接入点，包括：收发器、存储器以及与所述存储器耦合的处理器，所述收发器、存储器以及与所述存储器耦合的处理器相互连接，其中，所述收发器用于执行接收或发送动作，所述存储器用于存储第二方面描述的同步方法的实现代码，所述处理器用于调用所述存储器中存储的实现代码， 即执行第二方面及其各种可能的实现方式中的任意一种所提供的同步方法。
第七方面，本申请实施例提供了一种系统，包括：第一接入点和第二接入点；其中，该第一接入点为第四方面及其各种可能的实现方式中的任意一种所述的接入点或第六方面及其各种可能的实现方式中的任意一种所述的接入点；该第二接入点为第三方面及其各种可能的实现方式中的任意一种所述的接入点或第五方面及其各种可能的实现方式中的任意一种所述的接入点。
第八方面，本申请实施例提供了一种计算机可读存储介质，所述计算机可读存储介质上存储有指令，当所述指令被处理器执行时，使得所述处理器执行第一方面及其各种可能的实现方式中的任意一种所提供的同步方法。
第九方面，本申请实施例提供了一种计算机可读存储介质，所述计算机可读存储介质上存储有指令，当所述指令被处理器执行时，使得所述处理器执行第二方面及其各种可能的实现方式中的任意一种所提供的同步方法。
第十方面，本申请实施例提供了一种计算机程序产品，所述程序产品被处理器执行时，使得所述处理器执行第一方面及其各种可能的实现方式中的任意一种所提供的同步方法。
第十一方面，本申请实施例提供了一种计算机程序产品，所述程序产品被处理器执行时，使得所述处理器执行第二方面及其各种可能的实现方式中的任意一种所提供的同步方法。
附图说明
图1a是本申请实施例提供的一种64QAM星座示意图；
图1b是本申请实施例提供的一种通过GPS Clock来消除各接入点的载波之间的频差的原理示意图；
图1c是本申请实施例提供的一种通过时钟分发板来消除各接入点的载波之间的频差的原理示意图；
图2a是本申请实施例提供的一种接入点间通过有线连接的场景示意图；
图2b是本申请实施例提供的另一种接入点间通过无线连接的场景示意图；
图3是本申请实施例提供的一种同步方法的示意流程图；
图4a是本申请实施例提供的一种第一接入点与第二接入点间交互示意图；
图4b是本申请实施例提供的另一种第一接入点与第二接入点间交互示意图；
图4c是本申请实施例提供的一种单音信号在某个采样时刻的相位差的示意图；
图4d是本申请实施例提供的第一接入点与第二接入点同步发送目标数据帧的示意图；
图4e是本申请实施例提供的接入点的发送和接收时延和的示意图；
图4f是本申请实施例提供的一种情形下第二接入点对目标数据帧进行相位补偿的示意图；
图4g是本申请实施例提供的另一种情形下第二接入点对目标数据帧进行相位补偿的示意图；
图5是本申请实施例提供的一种接入点的结构示意图；
图6是本申请实施例提供的另一种接入点的结构示意图；
图7是本申请实施例提供的又一种接入点的结构示意图；
图8是本申请实施例提供的又一种接入点的结构示意图。
具体实施方式
请参见图2a，图2a是本申请实施例提供的一种通过Network MIMO技术进行同步的应用场景示意图。
如图2a所示，该场景可包括n个接入点(AP)，m个移动台，各接入点间可通过有线(如以太网或光纤)进行连接，且以接入点1为主AP为例，以接入点2为被AP为例，以其他(n-2)个接入点都为从AP为例。其中，各个接入点配置有至少一根天线，各个移动台配置有至少一根天线。各个接入点间的距离可为1米、10米、数百米或数公里，此处不作限制。
应当说明的，各接入点间还可通过无线进行连接，如图2b所示，该场景也包括n个接入点(AP)，m个移动台，各接入点间通过无线进行连接，且以接入点1为主AP为例，以接入点2为被AP为例，以其他(n-2)个接入点都为从AP为例。其中，各个接入点配置有至少一根天线，各个移动台配置有至少一根天线。各个接入点间的距离可为1米、10米、数百米或数公里，此处不作限制。
从图2a或图2b所述的场景中可以看出，各接入点采样独立的晶振源，由于无法保证晶振的完全一致，晶振间或多或少存在微小的频差，即使频差微小，也会导致接入点间的相位旋转，由于相位旋转，由n个接入点协作进行发射的信号存在相位误差的累积，经过信道作用之后，移动台接收到的接入点协作发射的信号的相对相位在不断旋转，误码率上升，最终，移动台无法对接收到的信号进行解码。其中，上述相对相位是随时间变化的，频差越大，相位差的变化量越快，误码率越高。
下面针对上述任一场景中的各接入点间的频差问题，本申请实施例结合图3详细描述本申请实施例提供的一种同步的方法，图3示例性示出了一种同步的方法的示意流程图，如图3所示，该方法可至少包括以下几个步骤：
S101、第一接入点生成单音信号。
本申请实施例中，以第一接入点为主AP，以第二接入点为从AP为例。
单音信号为频率单一的信号；例如，单音信号可为单一频率的正弦信号。
单音信号可包括在第一数据帧中，第一数据帧还可包括目标数据帧，单音信号在第一数据帧中的时间位置可早于目标数据帧在第一数据帧中的时间位置。其中，该目标数据帧为移动台期望从接入点接收到的数据，第一数据帧还可包括一些字段(如L-STF、L-LTF、L-SIG、RL-SIG、HE-SIG-A以及HE-STF等),移动台可根据上述字段解析出目标数据帧。举例来说，第一数据帧可为802.11帧。
S102、第一接入点发送单音信号。相应地，第二接入点接收第一接入点发送的单音信号。
本申请实施例中，第二接入点接收第一接入点发送的单音信号之前，第二接入点可接收第一接入点发送的指示信息；指示信息可包括用于指示单音信号的以下参数:单音信号的原始频率及单音信号的时间位置。其中，单音信号可以包括在第一数据帧中，且可通过数字或文字指示出单音信号在第一数据帧中的位置。应当说明的，指示信息还可以包括以下参数：单音信号中相位突变值的数量、单音信号的持续时间、单音信号与目标数据帧的时间间隔等。
第二接入点接收第一接入点发送的指示信息可包括以下两种实现方式。
第一种实现方式：通过应用层交互，第二接入点接收第一接入点发送的指示信息。
具体实现方式，如图4a所示，第一接入点将封装在TCP/UDP报文中的指示信息发送给第二接入点,第二接入点接收到指示信息后，将接收到指示信息的确认信息发送给第一接入点。
第二种实现方式：通过MAC层交互，第二接入点接收第一接入点发送的指示信息。
具体实现方式，如图4b所示，第一接入点将封装在802.11Action帧中的指示信息发送给第二接入点，第二接入点接收到指示信息后，一方面，第二接入点可不作任何响应。另一方面，响应于接收到的指示信息，第二接入点可向第一接入点发送一个ACK帧；或者，第二接入点可将接收到指示信息的确认信息封装在802.11Action帧中，然后，第二接入点将封装有确认信息的802.11Action帧发送给第一接入点。
应当说明的，指示信息还可封装在包括有单音信号的第一数据帧中，进而，第一接入点
可将单音信号与用于指示单音信号的指示信息发送给第二接入点。
S103、第二接入点可根据单音信号确定第一载波和第二载波的频差；第一载波可用于第一接入点发送单音信号；第二载波可用于第二接入点接收单音信号。
本申请实施例中，该频差可以等于单音信号在单位时间内的相位差的变化量减去单音信号的原始频率。具体推导过程如下：
下面通过表达式分别对第一载波、第二载波及单音信号进行表示，例如：
第一载波可表示为:
C m＝A m*(W m*t+Q m)(1)
第二载波可表示为：
C s＝A s*(W s*t+Q s)(2)
单音信号可表示为：
S a＝A a*(W a*t+Q a)(3)
第一接入点向第二接入点发送调制有单音信号的发射信号S a1，S a1可表示为：
S a1
＝S a*C m
＝A a*cos(W a*t+Q a)*A m*cos(W m*t+Q m)
＝A a*A m*cos(W m*t+Q m)*cos(W a*t+Q a)
＝(1/2)*A m*A a*[cos(W m*t+Q m+W a*t+Q a)+cos(W m*t+Q m+W a*t-Q a)](4)
＝A a1*[cos[(W m+W a)*t+Q a1]+cos[(W m-W a)*t+Q a2]]
其中，A a1＝(1/2)*A m*A a，Q a1＝Q m+Q a，Q a2＝Q m-Q a。
如(4)式所示，发射信号S a1可包括以下频率分量：(W m+W a)和(W m-W a)。
进一步的，第二接入点可通过第二载波对接收到的发射信号S a1进行解调，解调后的信号可包括以下频率分量：(W m+W a+W s)、(W m-W a+W s)、(W m+W a-W s)和(W m-W a-W s)。
其中，第二接入点可通过带通滤波器将频率分量(W m+W s)过滤，因而，解调后的信号将只剩以下两个频率分量：(W m+W a-W s)和(W m-W a-W s)。
进而，第二接入点将解调后的只包含(W m+W a-W s)和(W m-W a-W s)的信号经过以W a为中心频率的低带通滤波器将进行过滤后，信号中只剩下频率分量：(W m+W a-W s)。
然后，通过将测量出的该低带通滤波器的输出信号的相位变化除以对应的时间变化(单音信号在单位时间内的相位差的变化量)，可求出频率分量(W m+W a-W s)的值。
最后，(W m+W a-W s)减去W a，可求出频差(W m-W s)，即第一载波和第二载波的频差。
综上所述，该频差等于单音信号在单位时间内的相位差的变化量减去单音信号的原始频率。
下面详细阐述如何确定出单音信号在某个采样时刻的相位差。
如图4c所示，第二接入点可对单音信号的虚部信号和实部信号分别进行采样。第二接入点可根据单音信号在某个采样时刻的实部和虚部，通过反正切函数，得到在该时刻下的反正切结果，该反正切结果作为单音信号在该采样时刻的相位差。
应当说明的，某个采样时刻下的反正切结果：小于90度且大于-90度，单音信号在某个采样时刻的相位差满足以下规则：
如果某个采样时刻的单音信号的实部小于0，则该反正切结果增加180度。
如果该反正切结果小于0，则该反正切结果增加360度。
举例来说，在采样时刻5671，第二接入点可根据单音信号在该采样时刻的实部和虚部，通过反正切函数，可确定出单音信号在该时刻下的相位差为296.4度。
其中，单音信号在单位时间内的相位差的变化量由单音信号的持续时间内的多个采样时刻的相位差确定。具体可包括：在以下三种情形下，单音信号在单位时间内的相位差的变化量的确定。
第一种情形：如果单音信号的持续时间内的多个采样时刻即为两个采样时刻，则单音信号在单位时间内的相位差的变化量为：单音信号在第一采样时刻的相位差与单音信号在第二采样时刻的相位差的差值除以上述两个采样时刻之间的时间间隔的值。
第二种情形：如果单音信号的持续时间内的多个采样时刻为至少三个以上的采样时刻，则单音信号在单位时间内的相位差的变化量为：单音信号在任意两个采样时刻的相位差的差值除以该两个采样时刻之间的时间间隔的值。
第三种情形：如果单音信号的持续时间内的多个采样时刻为至少三个以上的采样时刻，则单音信号在单位时间内的相位差的变化量为：单音信号在任意两个时刻确定出的单位时间内的相位差的变化量的平均值。
如果多个采样时刻包括在多个单音信号的持续时间内的采样时刻，可通过以下两种方式确定频差。其中，所述多个单音信号可位于同一个第一数据帧中，也可位于不同的第一数据帧中。
第一种方式：频差等于多个单音信号各自在单位时间内的相位差的变化量的平均值减去单音信号的原始频率。
以该多个单音信号为两个单音信号为例，其中一个单音信号为单音信号1，另一个单音信号为单音信号2。
首先，可分别确定出单音信号1在单位时间内的相位差的变化量1，单音信号2在单位时间内的相位差的变化量2，然后，对变化量1与变化量2求平均值，可求得变化量3,最后，频差等于变化量3减去单音信号的原始频率的值。
通过该实现方式，可降低单音信号在单位时间内的相位差的变化量的测量误差。
第二种方式：单音信号在单位时间内的相位差的变化量等于第一持续时间内单音信号的相位差的变化量除以第一持续时间，第一持续时间等于该两个单音信号的持续时间与该两个单音信号的持续时间之间的时间间隔相加。
以该多个单音信号为两个单音信号为例，其中一个单音信号为单音信号3，另一个单音信号为单音信号4。
假设单音信号3和单音信号4的持续时间都为4us，频率都为250Khz，且单音信号3与单音信号4之间的时间间隔为480us。
如果单音信号3在初始时刻的相位差为17度，单音信号3在终止时刻的相位差为37度，且单音信号3的持续时间内包括一个360度的相位变化；单音信号4在初始时刻的相位差为277度，单音信号4在终止时刻的相位差为296度，且单音信号4的持续时间内包括一个360度的相位变化。
首先，第二接入点可根据单音信号的首尾相位差的变化量可确定出上述时间间隔480us内相位差旋转的360度的个数近似为126.66(即120+(37-17)*(480/4)/360＝126.66)个，取整后为126个。因此，第二接入点可确定出上述时间间隔480us内相位差旋转的360度的个数为126。
进而，结合单音信号3的持续时间内相位差旋转的360度的个数，单音信号4的持续时间内相位差旋转的360度的个数、上述时间间隔480us内相位差旋转的360度的个数、单音信号3的起始相位差与单音信号4的终止相位差的差值，可确定出单音信号在总时延488us(即4us+4us+480us＝488us)内的相位变化S。
S＝360+126*360+360+296-17＝46557(度)
然后，第二接入点可确定出单音信号在单位时间内的相位差的变化量为：94.994(度/us)(即46357度/488us)。
最后，频差S1等于单音信号在单位时间内的相位差的变化量减去单音信号的原始频率。
S1＝94.994度/us-1us*250Khz*360度＝4.994度/us
因此单音信号在单位时间内的相位差的变化量为4.994度/us。
通过该实现方式，可降低单音信号在单位时间内的相位差的变化量的测量误差。
应当说明的，单音信号的持续时间内的多个采样时刻至少包括：单音信号的开始时刻和单音信号的结束时刻。该实现方式中的采样时刻为优选的采样时刻，通过该实现方式，单音信号在单位时间内的相位差的变化量的测量误差较小。
应当说明的，如果单音信号在第一数据帧中的时间位置晚于目标数据帧在第一数据帧 中的时间位置，则第二接入点可根据在接收到第一数据帧之前的接收到的第二数据帧中的单音信号确定出第一载波和第二载波之间的频差。
S104、第二接入点基于频差对目标数据帧进行相位补偿，以使得第二载波的相位与第一载波的相位之间的差值小于或等于第一阈值。
本申请实施例中，目标数据帧为编码后的目标数据帧。第一载波的相位为第一发射信号的相位，第二载波的相位为第二发射信号的相位；其中，第一发射信号是目标数据帧调制在第一载波上所生成的信号，第二发射信号是相位补偿后的目标数据帧调制在第二载波上所述生成的信号。其中，该差值是一个变化的值，在不同的时刻，该差值不同。
也即是说，第二载波的相位与第一载波的相位之间的差值小于或等于第一阈值相当于第一发射信号的相位与第二发射信号的相位之间的差值小于或等于第一阈值。
第二接入点可在以下三个时刻基于频差对目标数据帧进行相位补偿。
在目标数据帧的初始时刻，第二接入点基于频差对目标数据帧进行相位补偿；
或者在目标数据帧的初始时刻之前，第二接入点基于频差对目标数据帧进行相位补偿；
或者在目标数据帧的初始时刻之后，第二接入点基于频差对目标数据帧进行相位补偿；
下面以在目标数据帧的初始时刻，第二接入点基于频差对目标数据帧进行相位补偿为例。
第二接入点对目标数据帧进行相位补偿可包括以下两种方式。
第一种方式：如果单音信号在单位时间内的相位差的变化量较小，则在目标数据帧的持续时间内，第二接入点对目标数据帧中的单个符号内的各个采样点采用同一个补偿值进行相位补偿。
例如，如图4f所示，从AP1确定出单音信号在1.05us时刻的相位差为-30度(即第二载波的相位超前于第一载波的相位30度),如果单音信号在单位时间内的相位差的变化量为0.0125度/us(主AP每1us将超过从AP1 0.0125度)，则在调制有目标数据帧的发射信号的持续时间内，第二接入点对目标数据帧中的单个符号内的各个采样点采用同一个补偿值进行相位补偿。
第二种方式：如果单音信号在单位时间内的相位差的变化量较小，则在目标数据帧的持续时间内，第二接入点对目标数据帧中的单个符号内的各个采样点采用不同的补偿值进行相位补偿。
例如，如图4g所示，从AP2确定出单音信号在1.10us时刻的相位差为85度(即第二载波的相位落后于第一载波的相位85度),如果单音信号在单位时间内的相位差的变化量为0.551度/us(主AP每1us将超过从AP1 0.551度)，第二接入点对调制有目标数据帧中的单个符号内的各个采样点采用不同的补偿值进行相位补偿。
上述相位补偿的实现方式，针对不同的场景，提供了不同的相位补偿方案，可降低运算复杂度，提高相位补偿的准确度。
应当说明的，在实际应用场景中，第一阈值的大小与由各接入点构成的系统的信号噪声比(Signal-Noise Ratio，SNR)有关。例如，当SNR>＝30dB时，第一阈值为1.44度，当SNR＝10dB时，第一阈值为3.80度。
S105、第一接入点发送目标数据帧至终端。
具体的，如步骤104所述，目标数据帧调制在第一载波上，生成第一发射信号。接着，第一接入点通过发送第一发射信号的方式将上述目标数据帧进行发送。
S106、第二接入点通过第二载波发送相位补偿后的目标数据帧至终端。
本申请实施例中，如步骤104所述，相位补偿后的目标数据帧调制在第二载波上，生成第二发射信号。接着，第二接入点通过发送第二发射信号的方式将上述相位补偿后的目标数据帧进行发送。
应当说明的，第二接入点发送相位补偿后的目标数据帧的时刻和第一接入点发送目标数据帧的时刻相同。
下面详细阐述如何分别确定出第一接入点发送目标数据帧的时间位置以及第二接入点发送相位补偿后的目标数据帧的时间位置。具体的：
第一接入点发送目标数据帧的时刻为第一时刻，第一时刻为与第一接入点发送相位突变值时相距第一时间间隔的时刻；相位突变值包括在单音信号中。
第二接入点发送相位补偿后的目标数据帧的时刻为第二时刻，第二时刻为与第二接入点检测到相位突变沿时相距第一时间间隔的时刻；相位突变沿与相位突变值关联。
其中，单音信号中相位突变值的个数可为单个或多个。
其中，目标数据帧的时刻可为目标数据帧的初始时刻或目标数据帧的终止时刻；相位调制后的目标数据帧的时刻可为相位调制后的目标数据帧的初始时刻或相位调制后的目标数据帧的终止时刻。
下面以第一时刻为目标数据帧的初始时刻，第二时刻为相位补偿后的目标数据帧的初始时刻为例，以第一接入点为主AP为例，以第二接入点为从AP1或从AP2为例。如图4d所示，主AP发送相位突变值的时刻与主AP发送目标数据帧的时刻相距38us；从AP1在1.05us时刻检测到相位突变沿，从AP1考虑到相位突变沿距离待进行相位补偿的目标数据帧的初始时刻的时间间隔为38us，因此从AP1发送相位补偿后的目标数据帧的时刻为39.05us。从AP2在1.10us时刻检测到相位突变沿，从AP2考虑到相位突变沿距离待进行相位补偿的目标数据帧的初始时刻的时间间隔为38us，因此从AP2发送相位补偿后的目标数据帧的时刻为39.10us。假设从AP1的发送和接收时延和为1.35us，从AP2的发送和接收时延和为1.20us，如果从AP1考虑发送和接收时延和，则从AP1需要在37.70us时发送相位补偿后的目标数据帧，如果从AP2考虑发送和接收时延和，则从AP2需要在37.90us时发送相位补偿后的目标数据帧。
其中，如图4e所示，从AP可通过自发自收的方式确定出发送和接收时延和。
例如，从AP在S1时刻发送出一个符号，在R1时刻接收到该符号，则该从AP的发送和接收时延和为(S1-R1)。
图4a-图4g仅用于解释本申请实施例，不应对本申请作出限制。
本申请实施例提供了一种接入点，图5示例性示出了一种接入点，其中，接入点50为图3方法实施例中的第二接入点。
如图5所示，接入点50可包括：接收单元501、处理单元502以及发送单元503。
接收单元501，用于接收第一接入点发送的单音信号。
处理单元502，用于根据单音信号确定第一载波与第二载波的频差；第一载波用于第一接入点发送第一数据帧；第二载波用于第二接入点接收第一数据帧。
处理单元502，还用于基于该频差对目标数据帧进行相位补偿，以使得第二载波的相位与第一载波的相位之间的差值小于或等于第一阈值。
发送单元503，用于通过所述第二载波发送相位补偿后的所述目标数据帧。
接收单元501，还可用于在接收第一接入点发送的单音信号之前，接收第一接入点发送的指示信息；指示信息可包括用于指示单音信号的以下参数：单音信号的原始频率及单音信号的时间位置。
具体的，单音信号包括在第一数据帧中，第一数据帧还可包括目标数据帧，单音信号在第一数据帧中的时间位置可早于目标数据帧在第一数据帧中的时间位置。
单音信号在单位时间内相位差的变化量由单音信号的持续时间内的多个采样时刻的相位差确定。
上述多个采样时刻包括在多个单音信号的持续时间内的采样时刻。
上述频差等于多个单音信号各自在单位时间内的相位差的变化量的平均值减去单音信号的原始频率。
单音信号在单位时间内的相位差的变化量等于第一持续时间内单音信号的相位差的变化量除以第一持续时间，第一持续时间等于两个所述单音信号的持续时间与两个所述单音信号的持续时间之间的时间间隔相加。
单音信号的持续时间内的多个采样时刻至少包括：单音信号的开始时刻和单音信号的结束时刻。
处理单元502，具体用于：
在目标数据帧的初始时刻，基于频差对目标数据帧进行相位补偿；
或者在目标数据帧的初始时刻之前，基于频差对目标数据帧进行相位补偿；
或者在目标数据帧的初始时刻之后，基于频差对目标数据帧进行相位补偿。
所述发送单元发送相位补偿后的所述目标数据帧的时刻和所述第一接入点发送所述目标数据帧的时刻相同；
第一接入点发送目标数据帧的时刻为第一时刻，第一时刻为与第一接入点发送相位突变值时相距第一时间间隔的时刻；相位突变值包括在单音信号中；
发送单元503发送相位补偿后的目标数据帧的时刻为第二时刻，第二时刻为与第二接入点检测到相位突变沿时相距第一时间间隔的时刻；该相位突变沿与该相位突变值关联。
应当理解，接入点50涉及的具体技术特征可参考图3方法实施例中的描述，接入点50仅为本申请实施例提供的一个例子，并且，接入点50可具有比示出的部件更多或更少的部件，可以组合两个或更多个部件，或者可具有部件的不同配置实现。
本申请实施例提供了另一种接入点，图6示例性示出了一种接入点，其中，接入点60为图3方法实施例中的第一接入点。
如图6所示，接入点60可包括：处理单元601以及发送单元602。
处理单元601，用于生成单音信号，所述单音信号用于确定第一载波与第二载波的频 差；所述第一载波用于所述第一接入点发送所述单音信号；所述第二载波用于第二接入点接收所述单音信号。
发送单元602，用于向所述第二接入点发送所述单音信号。
发送单元602，还用于在向所述第二接入点发送所述单音信号之前，向所述第二接入点发送指示信息；所述指示信息用于指示所述单音信号的以下参数；所述单音信号的原始频率及所述单音信号的时间位置。
具体的，单音信号包括在第一数据帧中，第一数据帧还包括目标数据帧，单音信号在第一数据帧中的时间位置早于目标数据帧在第一数据帧中的时间位置。
单音信号在单位时间内的相位差的变化量由单音信号的持续时间内的多个采样时刻的相位差确定。
多个采样时刻包括在多个单音信号的持续时间内的采样时刻。
上述频差等于多个单音信号各自在单位时间内的相位差的变化量的平均值减去单音信号的原始频率。
单音信号在单位时间内的相位差的变化量等于第一持续时间内单音信号的相位差的变化量除以第一持续时间，第一持续时间等于两个单音信号的持续时间与两个所述单音信号的持续时间之间的时间间隔相加。
单音信号的持续时间内的多个采样时刻至少包括：单音信号的开始时刻和单音信号的结束时刻。
第二接入点发送相位补偿后的目标数据帧的时刻和发送单元602发送所述目标数据帧的时刻相同；
发送单元602发送目标数据帧的时刻为第一时刻，第一时刻为与发送单元602发送相位突变值时相距第一时间间隔的时刻；相位突变值包括在单音信号中；
第二接入点发送目标数据帧的时刻为第二时刻，第二时刻为与第二接入点检测到相位突变沿时相距第一时间间隔的时刻；该相位突变值与该相位突变沿关联。
应当理解，接入点60涉及的具体技术特征可参考图3方法实施例中的描述，接入点60仅为本申请实施例提供的一个例子，并且，接入点60可具有比示出的部件更多或更少的部件，可以组合两个或更多个部件，或者可具有部件的不同配置实现。
本申请实施例提供了又一种接入点，图7示例性示出了一种接入点，其中，接入点70为图3方法实施例中的第二接入点。
如图7所示，接入点70可包括：处理器701、存储器702、收发器703。其中，收发器703、存储器702以及与存储器702耦合的处理器701相互连接。
存储器702可为永久性存储器、如闪存和硬盘驱动器，存储器702用于存储同步代码，该同步代码可被处理器701访问和调用。
收发器703，用于接收第一接入点发送的单音信号。
处理器701，用于访问和调用存储于存储器702中的上述同步代码，执行下述步骤：
步骤一：可根据收发器703接收到的第一接入点发送的单音信号，确定第一载波与第二载波的频差；第一载波可用于接入点70发送第一数据帧；第二载波可用于接入点70接 收所述第一数据帧。
步骤二：基于上述频差对目标数据帧进行相位补偿，以使得第二载波的相位与第一载波的相位之间的差值小于或等于第一阈值。
收发器703，还用于通过第二载波发送相位补偿后的目标数据帧。
应当理解，接入点70涉及的具体技术特征可参考图3方法实施例中的描述，接入点70仅为本申请实施例提供的一个例子，并且，接入点70可具有比示出的部件更多或更少的部件，可以组合两个或更多个部件，或者可具有部件的不同配置实现。
本申请实施例提供了又一种接入点，图8示例性示出了一种接入点，其中，接入点80为图3方法实施例中的第一接入点。
如图8所示，接入点80可包括：处理器801、存储器802、收发器803。其中，收发器803、存储器802以及与存储器802耦合的处理器801相互连接。
存储器802可为永久性存储器、如闪存和硬盘驱动器，存储器802用于存储同步代码，该同步代码可被处理器801访问和调用。
处理器801，用于访问和调用存储于存储器802中的上述同步代码，生成单音信号，单音信号用于确定第一载波与第二载波的频差；第一载波用于第一接入点发送单音信号；第二载波用于第二接入点接收单音信号。
收发器803，用于向第二接入点发送单音信号。
收发器803，还用于发送目标数据帧。
应当理解，接入点80涉及的具体技术特征可参考图3方法实施例中的描述，接入点80仅为本申请实施例提供的一个例子，并且，接入点80可具有比示出的部件更多或更少的部件，可以组合两个或更多个部件，或者可具有部件的不同配置实现。
可选地，当上述实施例的同步方法中的部分或全部通过软件实现时，上述接入点也可以只包括处理器。用于存储程序的存储器位于接入点之外，处理器通过电路/电线与存储器连接，用于读取并执行存储器中存储的程序。
处理器可以是中央处理器(Central Processing Unit，CPU)，网络处理器(Network Processor，NP)或者CPU和NP的组合。
处理器还可以进一步包括硬件芯片。上述硬件芯片可以是专用集成电路(Application-specific Integrated Circuit，ASIC)，可编程逻辑器件(Programmable Logic Device，PLD)或其组合。上述PLD可以是复杂可编程逻辑器件(Complex Programmable Logic Device，CPLD)，现场可编程逻辑门阵列(Field-programmable Gate Array，FPGA)，通用阵列逻辑(Generic Array Logic，GAL)或其任意组合。
存储器可以包括易失性存储器(volatile memory)，例如随机存取存储器(Random-Access Memory，RAM)；存储器也可以包括非易失性存储器(non-volatile memory)，例如快闪存储器(flash memory)，硬盘(Hard Disk Drive，HDD)或固态硬盘(Solid-State Drive，SSD)；存储器还可以包括上述种类的存储器的组合。
本申请实施例还提供了一种计算机存储介质，存储有计算机程序，该计算机程序用于执行上述实施例提供的同步方法。
本申请实施例还提供了一种包含指令的计算机程序产品，当其在计算机上运行时，使得计算机执行上述实施例提供的同步方法。
本领域内的技术人员应明白，本申请的实施例可提供方法、系统、或计算机程序产品。因此，本申请可采用完全硬件实施例、完全软件实施例、或结合软件和硬件方面的实施例的形式。而且，本申请可采用在一个或多个其中包含有计算机可用程序代码的计算机可用存储介质(包括但不限于磁盘存储器、CD-ROM、光学存储器等)上实施的计算机程序产品的形式。
本申请的说明书和权利要求书及附图中的术语“第一”和“第二”是用于区别类似的对象，而不必用于描述特定的顺序或先后次序。应该理解，这样使用的数据在适当情况下可以互换，以便这里描述的本申请的实施例，例如能够以除了在这里图示或描述的那些以外的顺序实施。此外，术语“包括”以及他们的任何变形，意图在于覆盖不排他的包含，例如，包含了一系列步骤或单元的过程、方法或设备(接入点)不必限于清楚地列出的那些步骤或单元，而是可包括没有清楚地列出的或对于这些过程、方法或设备(接入点)固有的其它步骤或单元。
本申请是参照根据本申请实施例的方法、设备(系统)、和计算机程序产品的流程图和/或方框图来描述的。应理解可由计算机程序指令实现流程图和/或方框图中的每一流程和/或方框、以及流程图和/或方框图中的流程和/或方框的结合。可提供这些计算机程序指令到通用计算机、专用计算机、嵌入式处理机或其他可编程数据处理设备的处理器以产生一个机器，使得通过计算机或其他可编程数据处理设备的处理器执行的指令产生用于实现在流程图一个流程或多个流程和/或方框图一个方框或多个方框中指定的功能的装置。
这些计算机程序指令也可存储在能引导计算机或其他可编程数据处理设备以特定方式工作的计算机可读存储器中，使得存储在该计算机可读存储器中的指令产生包括指令装置的制造品，该指令装置实现在流程图一个流程或多个流程和/或方框图一个方框或多个方框中指定的功能。
这些计算机程序指令也可装载到计算机或其他可编程数据处理设备上，使得在计算机或其他可编程设备上执行一系列操作步骤以产生计算机实现的处理，从而在计算机或其他可编程设备上执行的指令提供用于实现在流程图一个流程或多个流程和/或方框图一个方框或多个方框中指定的功能的步骤。

Claims (18)

  1. 一种同步方法，其特征在于，包括：
    第二接入点接收第一接入点发送的单音信号；
    所述第二接入点根据所述单音信号确定第一载波与第二载波的频差；所述第一载波用于所述第一接入点发送所述单音信号；所述第二载波用于所述第二接入点接收所述单音信号；
    所述第二接入点基于所述频差对目标数据帧进行相位补偿，以使得所述第二载波的相位与所述第一载波的相位之间的差值小于或等于第一阈值；
    所述第二接入点通过所述第二载波发送相位补偿后的所述目标数据帧。
  2. 如权利要求1所述的方法，其特征在于，所述第二接入点接收第一接入点发送的单音信号之前，还包括：
    所述第二接入点接收所述第一接入点发送的指示信息；所述指示信息用于指示所述单音信号的以下参数：所述单音信号的原始频率及所述单音信号的时间位置。
  3. 如权利要求1或2所述的方法，其特征在于，
    所述单音信号在单位时间内的相位差的变化量由所述单音信号的持续时间内的多个采样时刻的相位差确定。
  4. 如权利要求1所述的方法，其特征在于，所述第二接入点基于所述频差对目标数据帧进行相位补偿，具体为：
    在所述目标数据帧的初始时刻，所述第二接入点基于所述频差对目标数据帧进行相位补偿；
    或者在所述目标数据帧的初始时刻之前，所述第二接入点基于所述频差对目标数据帧进行相位补偿；
    或者在所述目标数据帧的初始时刻之后，所述第二接入点基于所述频差对目标数据帧进行相位补偿。
  5. 如权利要求1所述的方法，其特征在于，
    所述第二接入点发送相位补偿后的所述目标数据帧的时刻和所述第一接入点发送所述目标数据帧的时刻相同；
    所述第一接入点发送所述目标数据帧的时刻为第一时刻，所述第一时刻为与所述第一接入点发送相位突变值时相距第一时间间隔的时刻；所述相位突变值包括在所述单音信号中；
    所述第二接入点发送相位补偿后的所述目标数据帧的时刻为第二时刻，所述第二时刻为与所述第二接入点检测到相位突变沿时相距所述第一时间间隔的时刻；所述相位突变沿与所述相位突变值关联。
  6. 一种同步方法，其特征在于，包括：
    第一接入点生成单音信号，所述单音信号用于确定第一载波与第二载波的频差；所述第一载波用于所述第一接入点发送所述单音信号；所述第二载波用于第二接入点接收所述单音信号；
    所述第一接入点向所述第二接入点发送所述单音信号。
  7. 如权利要求6所述的方法，其特征在于，所述第一接入点向所述第二接入点发送所述单音信号之前，还包括：
    所述第一接入点向所述第二接入点发送指示信息；所述指示信息用于指示所述单音信号的以下参数：所述单音信号的原始频率及所述单音信号的时间位置。
  8. 如权利要求6或7所述的方法，其特征在于，
    所述单音信号在单位时间内的相位差的变化量由所述单音信号的持续时间内的多个采样时刻的相位差确定。
  9. 如权利要求6所述的方法，其特征在于，
    所述第二接入点发送相位补偿后的所述目标数据帧的时刻和所述第一接入点发送所述目标数据帧的时刻相同；
    所述第一接入点发送所述目标数据帧的时刻为第一时刻，所述第一时刻为与所述第一接入点发送相位突变值时相距第一时间间隔的时刻；所述相位突变值包括在所述单音信号中；
    所述第二接入点发送相位补偿后的所述目标数据帧的时刻为第二时刻，所述第二时刻为与所述第二接入点检测到相位突变沿时相距所述第一时间间隔的时刻；所述相位突变值与所述相位突变沿关联。
  10. 一种接入点，其特征在于，所述接入点为第二接入点，包括：
    接收单元，用于接收第一接入点发送的单音信号；
    处理单元，用于根据所述单音信号确定第一载波与第二载波的频差；所述第一载波用于所述第一接入点发送所述单音信号；所述第二载波用于所述第二接入点接收所述单音信号；
    所述处理单元，还用于基于所述频差对目标数据帧进行相位补偿，以使得所述第二载波的相位与所述第一载波的相位之间的差值小于或等于第一阈值；
    发送单元，用于通过所述第二载波发送相位补偿后的所述目标数据帧。
  11. 如权利要求10所述的接入点，其特征在于，
    所述接收单元，还用于在接收所述第一接入点发送的单音信号之前，接收所述第一接入点发送的指示信息；所述指示信息用于指示所述单音信号的以下参数：所述单音信号的原始频率及所述单音信号的时间位置。
  12. 如权利要求10或11所述的接入点，其特征在于，
    所述单音信号在单位时间内相位差的变化量由所述单音信号的持续时间内的多个采样时刻的相位差确定。
  13. 如权利要求10所述的接入点，其特征在于，所述处理单元，具体用于：
    在所述目标数据帧的初始时刻，基于所述频差对所述目标数据帧进行相位补偿；
    或者在所述目标数据帧的初始时刻之前，基于所述频差对所述目标数据帧进行相位补偿；
    或者在所述目标数据帧的初始时刻之后，基于所述频差对所述目标数据帧进行相位补偿。
  14. 如权利要求10所述的接入点，其特征在于，
    所述发送单元发送相位补偿后的所述目标数据帧的时刻和所述第一接入点发送所述目标数据帧的时刻相同；
    所述第一接入点发送所述目标数据帧的时刻为第一时刻，所述第一时刻为与所述第一接入点发送相位突变值时相距第一时间间隔的时刻；所述相位突变值包括在所述单音信号中；
    所述发送单元发送相位补偿后的所述目标数据帧的时刻为第二时刻，所述第二时刻为与所述第二接入点检测到相位突变沿时相距所述第一时间间隔的时刻；所述相位突变沿与所述相位突变值关联。
  15. 一种接入点，其特征在于，所述接入点为第一接入点，包括：
    处理单元，用于生成单音信号，所述单音信号用于确定第一载波与第二载波的频差；所述第一载波用于所述第一接入点发送所述单音信号；所述第二载波用于第二接入点接收所述单音信号；
    发送单元，用于向所述第二接入点发送所述单音信号。
  16. 如权利要求15所述的接入点，其特征在于，
    所述发送单元，还用于在向所述第二接入点发送所述单音信号之前，向所述第二接入点发送指示信息；所述指示信息用于指示所述单音信号的以下参数；所述单音信号的原始频率及所述单音信号的时间位置。
  17. 如权利要求15或16所述的接入点，其特征在于，
    所述单音信号在单位时间内的相位差的变化量由所述单音信号的持续时间内的多个采样时刻的相位差确定。
  18. 如权利要求15所述的接入点，其特征在于，
    所述第二接入点发送相位补偿后的所述目标数据帧的时刻和所述发送单元发送所述目标数据帧的时刻相同；
    所述发送单元发送所述目标数据帧的时刻为第一时刻，所述第一时刻为与所述发送单元发送相位突变值时相距第一时间间隔的时刻；所述相位突变值包括在所述单音信号中；
    所述第二接入点发送所述目标数据帧的时刻为第二时刻，所述第二时刻为与所述第二接入点检测到相位突变沿时相距所述第一时间间隔的时刻；所述相位突变值与所述相位突变沿关联。
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Families Citing this family (1)

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Publication number Priority date Publication date Assignee Title
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1998210A (zh) * 2004-01-28 2007-07-11 高通股份有限公司 用于在无线通信网络中进行频率捕获的系统和方法
CN102694762A (zh) * 2011-03-25 2012-09-26 北京新岸线无线技术有限公司 一种实现载波和采样时钟同步的方法、用户站点设备
CN103988449A (zh) * 2011-10-06 2014-08-13 麻省理工学院 分布式无线发射机的相干传输
US20170164387A1 (en) * 2014-07-18 2017-06-08 Interdigital Patent Holdings, Inc. Wireless local area network (wlan) uplink transceiver systems and methods

Family Cites Families (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10091616B2 (en) * 2005-12-15 2018-10-02 Polte Corporation Angle of arrival (AOA) positioning method and system for positional finding and tracking objects using reduced attenuation RF technology
CN101039145B (zh) * 2007-03-30 2010-08-04 华为技术有限公司 时钟的实现方法、装置
US8116419B2 (en) * 2008-07-14 2012-02-14 Alcatel Lucent Methods and apparatuses for estimating time delay and frequency offset in single frequency networks
CN102223322B (zh) * 2010-04-15 2014-11-05 中兴通讯股份有限公司 一种频率偏差的估计方法及装置
CN105228239B (zh) * 2010-05-31 2019-11-26 华为技术有限公司 基站和基站时钟同步方法
CN102546142B (zh) * 2010-12-11 2016-08-03 上海博达数据通信有限公司 透明时钟的频率同步方法以及同步报文的存储转发方法
CN102395189B (zh) * 2011-06-28 2017-03-22 中兴通讯股份有限公司 一种bbu堆叠系统中时钟同步的方法和系统
US8913632B2 (en) * 2011-08-05 2014-12-16 Khalifa University Of Science, Technology And Research Method and system for frequency synchronization
CN102347814B (zh) * 2011-10-11 2014-02-26 上海电力学院 基于主时钟频率差值的从时钟调整方法
CN104067555A (zh) * 2012-01-30 2014-09-24 索尼公司 同步处理设备、同步处理方法和程序
US9363777B2 (en) * 2012-06-14 2016-06-07 Nokia Solutions And Networks Oy Fast recovering for network listening schemes in synchronization over air for small cells
CN103684728B (zh) * 2012-09-04 2016-11-02 中国航空工业集团公司第六三一研究所 Fc网络时钟同步误差补偿方法
CN103117845A (zh) * 2012-11-13 2013-05-22 华为技术有限公司 一种透明时钟驻留时间的修正方法、装置及系统
WO2014107136A1 (en) * 2013-01-04 2014-07-10 Telefonaktiebolaget L M Ericsson (Publ) Method for estimating frequency offset using quasi-co-located reference signals
US9363776B2 (en) * 2013-09-30 2016-06-07 Qualcomm Incorporated High precision access point to access point synchronization in an indoor position location system
US9184861B2 (en) * 2013-10-01 2015-11-10 Khalifa University of Science, Technology, and Research Method and devices for synchronization
CN104683039B (zh) * 2013-11-28 2017-06-16 展讯通信（上海）有限公司 通信终端的晶振频率校准方法与校准装置
CN106656386B (zh) * 2015-10-30 2019-08-27 南京中兴新软件有限责任公司 一种本地时钟调整方法、授时方法及装置
CN107645768B (zh) * 2016-07-20 2020-09-25 工业和信息化部电信研究院 一种用于局内分配的时间同步方法和装置
CN106131947B (zh) * 2016-09-14 2019-11-05 潘进 一种无线网络设备间时钟同步的方法
CN108023723B (zh) * 2016-11-04 2021-07-09 华为技术有限公司 频率同步的方法以及从时钟
CN106357362B (zh) * 2016-11-07 2019-05-17 瑞斯康达科技发展股份有限公司 一种时间同步方法、装置及ptp系统
CN107085174B (zh) * 2017-05-18 2019-12-17 北京兴迪仪器有限责任公司 一种分布式局部放电检测系统的高精度时间同步方法

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1998210A (zh) * 2004-01-28 2007-07-11 高通股份有限公司 用于在无线通信网络中进行频率捕获的系统和方法
CN102694762A (zh) * 2011-03-25 2012-09-26 北京新岸线无线技术有限公司 一种实现载波和采样时钟同步的方法、用户站点设备
CN103988449A (zh) * 2011-10-06 2014-08-13 麻省理工学院 分布式无线发射机的相干传输
US20170164387A1 (en) * 2014-07-18 2017-06-08 Interdigital Patent Holdings, Inc. Wireless local area network (wlan) uplink transceiver systems and methods

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