WO2012146187A1

WO2012146187A1 - Clock synchronization processing method, device and communication system

Info

Publication number: WO2012146187A1
Application number: PCT/CN2012/074755
Authority: WO
Inventors: 余芳; 徐骁; 王燚
Original assignee: 华为技术有限公司
Priority date: 2011-04-26
Filing date: 2012-04-26
Publication date: 2012-11-01
Also published as: CN102761951B; CN102761951A

Abstract

A clock synchronization processing method, device and communication system are provided in the present invention, wherein the clock synchronization processing method comprises: acquiring time information of system date; according to the time information of system date and special system frame information, generating time information of air-interface date corresponding to the special system frame, wherein the time information of air-interface date corresponding to the special system frame is used for transferring the time information of system date between a Long Term Evolution (LTE) backhaul base station and a Long Term Evolution (LTE) backhaul user equipment; and transmitting an air-interface message including the time information of air-interface date corresponding to the special system frame to the LTE backhaul user equipment. A corresponding device and a communication system comprising the above described device are also provided in embodiments of the present invention. The above described solution provided in the embodiments of the present invention enables provision of high-accuracy time information of system date for a remote base station in the case of using the LTE for base station backhaul, thereby realizing the clock synchronization.

Description

Clock synchronization processing method, device and communication system

The present application claims priority to Chinese Patent Application No. 201110105686.7, entitled "Clock Synchronization Processing Method, Apparatus, and Communication System", filed on April 26, 2011, the entire contents of which are incorporated herein by reference. In the application. Technical field

The embodiments of the present invention relate to a time synchronization technology, and in particular, to a clock synchronization processing method, apparatus, and communication system. Background technique

The Long Term Evolution (LTE) architecture integrates the radio network controller (Radio Network Controller, RNC) and the base station NodeB in the 3GPP R6, that is, the evolved base station _e NodeB. The eNodeB provides Evolved Universal Terrestrial Radio Access (Evolved Universal Terrestrial Radio Access, E-UTRA) for radio link control (Radio Link Control, hereinafter referred to as: RLC) layer/wireless access control (Media Access) Control, the following is called: MAC) layer / packet data convergence protocol (Packet Data Convergence Protocol, the following: PDCP) layer and other physical layer protocol functions and radio resource control protocol layer (Radio Resource Control, hereinafter referred to as: RRC) The function. The whole system tends to be flat. This system structure and system change makes LTE less structurally and cost-effective than existing UTRA architectures; and in terms of performance, it helps to reduce data transmission delay.

Time division multiplexing TDD-LTE technology and frequency division multiplexing compared to previous wireless communication technologies

FDD-LTE technology can provide up to 50Μ uplink and up to 100M downlink bandwidth, far exceeding current 3G technology. This bandwidth is beneficial for operators to develop data services and mobile Internet services. In addition, the high-bandwidth feature of the LTE network makes the LTE base station backhaul a trend. The current LTE base station backhaul includes the following application scenarios, such as providing a backhaul for the hotspot coverage area and providing a backhaul for the base station inside the large building on the street side. , providing a backhaul for the base station covering the subway entrance, or a base station within the high-speed train Provide a return trip.

The LTE backhaul base station can perform backhaul for the small base station, so that one of the backhaul base stations covers multiple backhaul

The UE performs backhaul for multiple small base stations, or performs backhaul for the macro base station. An LTE backhaul base station can only cover one backhaul UE, and only returns to one macro base station. In addition, in the high-speed rail wireless backhaul scenario, such as GSM in the train. A small base station transmitter (GSM Pico BTS WCDMA base station, TD-SCDMA base station, LTE base station or WiFi access point is connected to the LTE backhaul UE on the train through a router, and then deployed through LTE backhaul base stations and gateways deployed on both sides of the rail The devices are connected. The data of each type of base station is transmitted to the gateway after being aggregated by the UE, and then forwarded by the router to the corresponding base station console BSC, the WCDMA radio network controller, the TD-SCDMA radio network controller, and the enhanced packet. The core network EPC is either a WiFi access controller.

Regardless of whether the LTE backhaul base station is used for the backhaul of the macro base station or the small base station, it is required to meet the synchronization requirements of the base stations of various standards. The requirements of different mobile networks for clock synchronization are as follows:

The above synchronization accuracy refers to the synchronization accuracy between the base station and the standard clock source. It can be seen from the above table that since the clock synchronization involves the air interface clock of the base station, the impact on the handover performance and the coverage performance is very large, so whether it is 2G or 3G. , or the super 3G base station has strict requirements on the accuracy of the clock frequency. The degree requirement is 0.05ppm. In addition, since the TDD base station uses the same frequency on the uplink and downlink, in order to avoid interference, the accuracy of the clock phase is also very strict, and is not greater than ^ ^s .

The Global Positioning System (GPS) is currently the technical solution for all mobile network clock synchronization needs, but GPS requires a receiver for each base station and ensures that the satellite is within the field of view of the ground base station. In the scenario where the LTE base station is used for the backhaul, some may be applied indoors, for example, providing backhaul for the base station inside the large building on the street side and providing a backhaul for the base station covering the subway entrance, which is not suitable for GPS synchronization.

In a wireless backhaul scenario, the LTE backhaul base station D-ENB obtains clock synchronization through the master clock or GNSS, and provides synchronization for the remote base station BTS as the master node, and the remote base station BTS can be regarded as the slave node. D-ENB and LTE backhaul The UE R-UE completes the backhaul of the BTS data through the air interface. One way to transfer TOD information between the master node and the slave node is to use the PRECISION CLOCK SYNCHRONIZATION PROTOCOL (hereinafter referred to as: ΡΤΡ), which defines four types of synchronization messages: Sync (Sync Message) ), FollowJJP (follow the message), Dday_Req (delay request), Delay_Resp (delay response). The synchronization process between a master clock master and a slave clock Slave is as follows:

The master node sends a Sync synchronization message to the slave node every 2 seconds. This message is a message marked with the expected transmission time. However, since the expected transmission time and the actual transmission of the text may be delayed, the time stamp cannot be sent with the synchronization message. This synchronization message is received by the slave node at the receiving end to receive the time stamp (in order to improve the accuracy, the transmission or reception time should be detected, recorded and identified at the physical layer or near the physical layer).

The master node sends a FollowJJP message to the slave node, which contains the tag of the exact transmission time of the previous synchronization message. The slave node uses these two time stamps to obtain the delay between it and the master node, and adjusts the clock frequency according to this.

The slave node sends a delay request Dday_Req message to the master node (the interval of the delay request message is independently set, and is generally longer than the synchronization message interval. This message is recorded by the slave node when it is accurately transmitted. Between, the primary node is marked with an accurate reception time stamp).

The master node returns a delayed response Dday_Resp message to the slave node. This message is tagged with the exact receipt time of the previous request message. The slave node uses this time and the exact transmission time recorded by it to calculate the delay of the transmission between the master node and the slave node to adjust its clock drift error.

Master and slave clock offset: offset=t2-tl-T, where link delay D = ( t2-tl+t4-t3 ) /2; offset time = ( t2- tl ) - ( t2- tl+ t4 -t3 ) 12= ( t2-tl-t4+t3 ) 12, Adjust the slave clock by the offset time.

In order to ensure the time precision, a timestamp can be set in the position between the physical layer and the MAC layer, and the synchronization is carried out by the packet interaction method carrying the time stamp, and of course, the transmission of the TOD information is also included. The format of the above time stamp is as follows:

Struct Timestamp

UInteger48 secondsField; 〃 32-bit unsigned integer

UInteger32 nanosecondsField; 〃48-bit unsigned integer

} ;

The Timestamp data type represents the positive time value from the time origin; the secondsField member is the integer part of the timestamp second value; the nanosecondsFiled member is the fractional part of the timestamp nanosecond, and the nanosecondsFiled member is usually less than 109.

In the above technical solution of clock synchronization, during the process of transmitting the time stamp on the air interface, due to the uncertainty of the wireless baseband processing and the wireless link environment, large delay jitter may be caused, which affects the accuracy of synchronization.

Therefore, in the prior art, in the application using the LTE base station for backhaul, there is a defect that the clock synchronization accuracy is low.

Summary of the invention

An embodiment of the present invention provides a clock synchronization processing method, apparatus, and communication system, which are used to provide high-precision system time-time information for a remote base station when LTE is used as a base station backhaul. Implement clock synchronization.

The embodiment of the invention provides a clock synchronization processing method, including:

Obtain system time information;

Generating air interface time information corresponding to a specific system frame according to the system time information and the specific system frame information, where the air interface time information corresponding to the specific system frame is used between the long term evolution backhaul base station and the long term evolution backhaul user equipment Transfer system time information;

The air interface message including the air interface day time information corresponding to the specific system frame is sent to the long term evolution backhaul user equipment.

The embodiment of the invention further provides another clock synchronization processing method, including:

The receiving the long-term evolution backhaul base station sends an air interface message including air interface day time information corresponding to the specific system frame, where the air interface day time information corresponding to the specific system frame is generated by the long-term evolution backhaul base station according to the system day time information and the specific system frame information, And used to transmit system time information between the long-term evolution backhaul base station and the long-term evolution backhaul user equipment;

The system time information is acquired based on the air interface day time information corresponding to the specific system frame and time synchronization is performed.

The embodiment of the invention further provides a clock synchronization processing device, including:

The first ear is used to obtain system time information;

An information generating module, configured to generate air interface time information corresponding to a specific system frame according to the system time information and the specific system frame information, where the air interface day time information corresponding to the specific system frame is used in the long term evolution backhaul base station and And the first sending module is configured to send, to the long-term evolution backhaul user equipment, an air interface message that includes the air interface time information corresponding to the specific system frame.

The embodiment of the invention further provides another clock synchronization processing device, including:

a receiving module, configured to receive, by the long-term evolution backhaul base station, an air interface message that includes air interface time and time information corresponding to a specific system frame, where the air interface time and time information corresponding to the specific system frame is long-term evolution The backhaul base station generates the system time information according to the system time information and the specific system frame information, and is used to transmit the system time time information between the long term evolution backhaul base station and the long term evolution backhaul user equipment;

The second ear is configured to acquire system time information according to the air interface time information corresponding to the specific system frame and perform time synchronization.

The present invention further provides a communication system, including a long term evolution backhaul base station and a long term evolution backhaul user equipment, the long term evolution backhaul base station includes the above clock synchronization processing apparatus, and the long term evolution backhaul user equipment includes the above clock synchronization processing apparatus. .

The clock synchronization processing method, device, and communication system of the embodiment of the present invention sends the air interface time information to the long-term evolution backhaul user equipment by using an air interface message, so that the system time information is recovered by the long-term evolution backhaul user equipment, and may be further transmitted. For the user side transceiver device, the user side transceiver device in this embodiment refers to a base station that is connected to the long term evolution backhaul user equipment and needs to provide a backhaul for the long term evolution backhaul base station, and is implemented as a remote base station when using LTE as a base station backhaul. Provides high-precision system time information for clock synchronization. DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the description of the prior art will be briefly described below. Obviously, the following description will be attached. The drawings are some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any creative work.

1 is a schematic flowchart of Embodiment 1 of a clock synchronization processing method according to the present invention;

2 is a schematic diagram of a system frame number change according to an embodiment of the present invention;

3 is a schematic diagram of a message format of a time-of-day message in an embodiment of the present invention;

4 is a schematic structural diagram of a backhaul base station according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of RRC signaling message transmission in an embodiment of the present invention;

6 is a schematic flowchart of Embodiment 2 of a clock synchronization processing method according to the present invention; FIG. 7 is a schematic structural diagram of an LTE backhaul UE according to an embodiment of the present invention;

8 is a schematic flow chart of a specific embodiment of the present invention;

9 is a schematic structural diagram of Embodiment 1 of a clock synchronization processing apparatus according to the present invention;

10 is a schematic structural diagram of an information generating module in the embodiment shown in FIG. 9;

11 is a schematic structural diagram of Embodiment 2 of a clock synchronization processing apparatus according to the present invention;

FIG. 12 is a schematic structural diagram of Embodiment 3 of a clock synchronization processing apparatus according to the present invention. detailed description

The technical solutions in the embodiments of the present invention are clearly and completely described in the following with reference to the accompanying drawings in the embodiments of the present invention. It is a partial embodiment of the invention, and not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

The embodiment of the present invention provides a clock synchronization processing method. FIG. 1 is a schematic flowchart of Embodiment 1 of a clock synchronization processing method according to the present invention. As shown in FIG. 1 , for the LTE backhaul base station side, the method includes the following steps:

Step 101: Obtain system time information. In this case, when the LTE is used as the base station backhaul, the LTE backhaul base station obtains the system time information from the clock source or the master clock, and may be recorded as Tod_sys;

Step 102: Generate air interface time information corresponding to a specific system frame according to the system time information and the specific system frame information, where the air interface time information corresponding to the specific system frame is used for the long-term evolution backhaul base station and the long-term evolution backhaul user. The system time information is transmitted between the devices. In this step, the LTE backhaul base station converts the acquired system time information Tod_sys into the air interface time information Tod_tx corresponding to the specific system frame transmitted on the air interface, and the system time time information is The frame number of the system frame (System Frame Number, hereinafter referred to as: SFN) is linked and passed; Step 103: Send an air interface message including the air interface time information corresponding to the specific system frame to the long term evolution backhaul user equipment. After the air interface time information is generated in the foregoing step, the air interface date information is sent to the long-term evolution backhaul user equipment by using the air interface message, so that the system time information is recovered by the long-term evolution backhaul user equipment, and may be further transmitted to the user. The side-side transceiver device, the user-side transceiver device in this embodiment refers to a base station that is connected to the long-term evolution backhaul user equipment and needs to provide a backhaul for the long-term evolution backhaul base station, and between the long-term evolution backhaul user equipment and the base station that needs the long-term evolution backhaul base station to provide the backhaul. It can be a wired connection. This embodiment can provide high-precision system time-of-day information for the remote base station and implement clock synchronization in the case of LTE for base station backhaul.

In addition, in the foregoing embodiment of the present invention, the LTE backhaul base station needs to convert the system time information Tod_sys obtained from the clock source or the master clock into the air interface time information Tod_tx obtained on the air interface according to the local timing relationship, and the main method is to set the time time information. Associated with the frame number SFN of the system frame, the time of day information corresponding to the specific SFN is transmitted on the air interface.

The air interface time information transmitted on the air interface between the LTE backhaul base station and the LTE backhaul UE may be a system day time value of a specific system frame start time, or a system time frame initialization time from a system frame to a specific system frame time system The number of periods in which the frame number of the frame has been cycled, and may be other variables that characterize the relationship between the system time value and the particular system frame.

Specifically, when the air interface time information is the system time value of the specific system frame start time, and the specific system frame is preset between the LTE backhaul base station and the LTE backhaul UE, that is, the LTE backhaul base station and the LTE backhaul UE are both The specific system frame corresponding to the system time value that can be explicitly transmitted may be determined by the LTE backhaul base station, and notified to the LTE backhaul UE by the air interface message alone, or configured by the system for the LTE backhaul base station and the LTE backhaul UE. The frame number of a particular system frame. For example, as shown in FIG. 2, each SFN cycle period includes 1024 system frames, and each system frame corresponds to one system frame pulse, and the duration of each system frame pulse is 10 ms. For example, the LTE backhaul base station can transmit the cycle to the LTE backhaul UE. The system time value corresponding to the first (or other preset specific position) pulse in the cycle, expressed by TOD_tx, TOD_tx can be transmitted once per SFN cycle. It can also be repeated multiple times, the sending timing is not fixed, but must be within the duration of the SFN cycle. In this embodiment, the LTE backhaul base station generates the air interface time and time information according to the system time information, which may be based on the system time information, the current system frame start time, the frame number of the current system frame, and the frame number of the specific system frame. Obtaining the system time value of the specific system frame start time, as shown in FIG. 2, acquiring the current system frame start time according to the current time value (ie, system day time information) and the current system frame start time value. The system time value, and then the system time value of the specific system frame can be obtained according to the difference between the frame number of the current system frame and the frame number of the specific system frame.

In the above embodiment, the frame number of the specific system frame is configured in advance on the LTE backhaul base station and the LTE backhaul UE, and the frame number of the specific system frame is not required to be pre-configured by the LTE backhaul base station. The system time value is carried in the air interface message and sent to the LTE backhaul UE. That is, the air interface time information includes the frame number of the specific system frame and the system time value of the specific system frame start time. In this embodiment, the LTE backhaul base station also needs to generate the air interface time and time information according to the system time information. Specifically, the system time value of the specific system frame start time obtained according to the system day time information, the current system frame start time, the frame number of the current system frame, and the frame number of the specific system frame.

In another embodiment, the air interface time information includes the number of cycles corresponding to the frame number of the specific system frame, or the number of cycles corresponding to the frame number of the specific system frame, and the specific system frame. Frame number. The number of cycles described above is the number of cycles in which the system frame number has been cycled from the system frame number initialization time to the specific system frame. Specifically, the SFN of the LTE base station can be calculated according to the following formula:

SFN = (time}mod{period(SFN)}

Where time represents the relative time from the start of the SFN initialization time (for example, setting SFN = 0 on on January 6, 1980 at 00:00:00 GMT time) to the start time of a particular system frame, in

10ms; and ^{periQd FN} ) indicates the cycle number of the frame number of the system frame, set to 1024 (corresponding relative time is 1024 10ms), and the value range of SFN is: 0-1023. According to the above formula, there is an integer N with a minimum value of 0, so that the following formula holds: tine = SFN + 1024* N

Therefore, within each SFN cycle period (including 1024 system frames), the LTE backhaul base station transmits the N value corresponding to the specific system frame to the LTE backhaul UE, represented by Tod_tx. The above N value represents the number of cycles in which the system frame number has been cycled from the system frame number initialization time to the specific system frame, and the time corresponding to the SFN initialization time is 10 ²⁴ * N 10 ms, plus The frame number SFN of the upper specific system frame, ^time represents the relative time of the specific system frame start time with respect to the SFN initialization time. The corresponding TOD value is time/100, and the unit is s. That makes:

TOD = {SFN + 1024* N}/ 100 or N = {TOD * 10θ}/1024

In this embodiment, Tod_tx is transmitted at least once in each SFN cycle, and may be repeatedly transmitted multiple times. The timing of the transmission does not need to be fixed, but needs to be within the duration of the preset SFN period.

In addition, the configuration of the frame number of the specific system frame may be configured in advance between the long-term evolution backhaul base station and the long-term evolution backhaul user equipment, and the foregoing generating the air interface time and time information according to the system time information may be The system time time information, the system frame start time, and the frame number cycle period of the system frame acquire the number of cycles corresponding to the frame number of the specific system frame.

In addition, the frame number of the specific system frame may be carried in the air interface message sent by the LTE backhaul base station to the LTE backhaul UE, that is, the air interface day time information includes the frame number of the specific system frame, and the specific system frame. The number of the loop period corresponding to the frame number, the air interface time and time information corresponding to the specific system frame is generated according to the system time information and the specific system frame information, and the method includes: according to the system time and time information, current The system frame start time and the cycle period of the frame number of the system frame acquire the number of cycles in which the frame number of the system frame has been cycled from the frame number initialization time of the system frame to the specific system frame.

The foregoing embodiment of the present invention provides a form of air interface time information, which can be carried in an air interface message, and the air interface message can be a message transmitted between the LTE backhaul base station and the LTE backhaul UE. The type of message, which can be a high-level message or some existing one. Order the message.

For the case of using the high-level message, the advantage is that the existing air interface process is not affected, that is, a new message can be defined to carry the TOD information, that is, the generation time-delivery message is encapsulated according to the air interface time and time information, and the time-time delivery message includes A message header and a payload field, the header of which is used to characterize the erasure type as a time-of-day delivery message, and the air interface time information is located in the payload field. The specific message format can be in the timestamp format, as shown in Figure 3.

The backhaul base station obtains the system time information Tod_sys from the external clock source, the frame timing module generates the air interface time information Tod_tx according to the local timing relationship and Tod_sys, and the message generating entity generates an air interface message according to the Tod_tx generated by the frame timing module, and encapsulates the message into an IP address. The data packet is sent by the sending module to the LTE backhaul UE along with other data services on the air interface. The IP address of the IP packet carrying the TOD information may be an address allocated by the OAM server, and the destination address may be an IP address allocated by the PDN-GW to the backhaul UE when the default bearer is established, as shown in FIG. 4 .

In addition, the existing RRC signaling, for example, the RRC reconfiguration message delivery air interface time information, that is, the radio resource control connection reconfiguration message including the air interface day time information, may be sent to the long term evolution backhaul user equipment, where the air interface is used. The day time information is encapsulated in an extension field of the above RRC connection reconfiguration message. Specifically, an RRC Connection Reconfiguration message may be used, and an IE TimeofDay_RUE carrying the TOD information is added to the message. When the TOD information is not required to be transmitted, the RRC connection reconfiguration message may not include the TimeofDay_RUE. save resources.

In addition, a special RRC signaling message may be added to specifically carry TOD information. As shown in FIG. 5, the LTE backhaul base station sends the LTE backhaul UE, and the message carries information related to the TOD. Corresponding LTE backhaul After receiving the message, the UE reads the TOD related information in the message, and then synchronizes the subsequent processing.

The specific implementation manner is as follows: Add a definition of a dedicated RRC signaling message in the downlink dedicated control channel message (DL-DCCH-Message): RUE Information Tod, the above The DL-DCCH-Message type message is a set of RRC messages sent by the network side to the UE on the downlink DCCH logical channel.

The newly defined RRC signaling message UE Information Tod can carry 90 bits of TOD information, and the size of the TOD information payload can vary according to the TOD information transmitted on the air interface.

In another embodiment, the LTE backhaul base station sends a dedicated system information block including air interface time information to the long-term evolution backhaul user equipment by adding a dedicated system information block (SIB) message. Message.

Specifically, for the system message in the prior art, the system message may include a master information block (Master Information Block, MIB) and an SIB, and the RRC message structure may be organized according to different functions and frequency of transmission. Form different SIBs. The system messages defined by the current protocol are as follows:

MIB, used for transmitting downlink bandwidth, system frame number SFN and PHICH configuration information; SIB-1, for transmitting cell access information and SIB (except SIB-1) scheduling information;

SIB-2, configured to transmit radio common resource configuration information of all UEs;

SIB-3 - SIB-8, used to transmit cell reselection information;

The SIB-9 is configured to transmit a Home eNB Identifier (HeNB ID);

SIB-10 ~ SIB-12, used to transmit information about ETWS and CMAS notifications;

SIB-13 is used to transmit information related to MBMS control messages.

In the embodiment of the present invention, an SIB-14 message is added to carry the TOD related information, and a specific system information message (Systemlnformation message) and an SIB-1 message (Systemlnformation Block Typel message) are added, and an indication of the SIB-14 message is added therein. In addition, the SIB-14 message includes 90 bits of TOD information, and the size of the TOD information payload may vary according to the TOD information transmitted on the air interface. For the update period processing of the SIB-14, a UE-specific discontinuous reception (UE Specific DRX) may be set for the LTE backhaul UE. (Discontinuous Reception ) ) parameters, the process is as follows:

The LTE backhaul UE sends the desired DRX cycle length to the MME on the core network side through the NAS message (Tracking Area Update or Attach message). The MME accepts the recommended value and configures the UE Specific DRX parameter related to the backhaul UE to the eNB.

After receiving the SIB-2 message, the UE compares the value of the UE Specific DRX and the default paging period (default Paging Cycle), and selects a smaller value as its DRX cycle length. The TOD information delivery period is related to the length of the DRX period of the LTE backhaul UE. The LTE backhaul UE can flexibly set its own DRX cycle length as needed.

In the foregoing embodiment of the present invention, the LTE backhaul base station sends the air interface time and time information to the LTE backhaul UE by using the air interface message, and after receiving the air interface message including the air interface time and time information, the LTE backhaul UE acquires the system date according to the air interface time and time information. Time information. FIG. 6 is a schematic flowchart of Embodiment 2 of a clock synchronization processing method according to the present invention, where the method includes:

Step 201: Receive a long-term evolution backhaul base station, and send an air interface message including air interface day time information corresponding to a specific system frame, where the air interface day time information corresponding to the specific system frame is a long-term evolution backhaul base station according to system time time information and a specific system frame. Information generation and used to transfer system time information between the long term evolution backhaul base station and the long term evolution backhaul user equipment;

Step 202: Acquire system time information according to the air interface day time information corresponding to the specific system frame, and perform time synchronization.

According to the foregoing method for the LTE backhaul base station, the air interface time information carried in the air interface message received by the LTE backhaul UE in this embodiment has various forms. For details, refer to the description in the foregoing embodiment, and There are also many types, as well as the description in the above embodiments.

Specifically, as shown in FIG. 7, the LTE backhaul UE includes a TOD receiving module and a TOD recovery module, where the TOD receiving module parses the data packet or signaling message carrying the TOD information, extracts the air interface TOD information, and then recovers by the TOD. Module based on local timing relationship and TOD receiving module The output of the air interface TOD information recovers the system time information and the pulse per second (PPS) information. In addition, because there is a delay in the delivery of the air interface message, it is possible that the system frame corresponding to the corresponding system frame relative air interface time information has already crossed an SFN cycle period when the backhaul UE receives the air interface time information. The TOD receiving module of the backhaul UE is responsible for judging this situation and making corrections. Specifically, the air interface time information includes a system time value of a specific system frame start time, and the specific system frame is pre-configured between the long-term evolution backhaul base station and the long-term evolution backhaul user equipment; or includes a frame number of a specific system frame, And a system time value of the specific system frame start time. This embodiment further includes the need for correction, that is, including:

When the frame number of the specific system frame is not in the frame number cycle period of the same system frame as the frame number of the current system frame, the system time value of the received specific system frame start time is corrected.

In addition, for the air interface time information, the number of cycles in which the frame number of the system frame has been cycled from the frame number initialization time of the system frame to the specific system frame may be the number of cycles, and the specific system The frame is pre-configured between the long-term evolution backhaul base station and the long-term evolution backhaul user equipment; or the air interface day time information includes the frame number of the specific system frame, and the frame of the system frame from the frame number initialization time of the system frame to the specific system frame Number of cycles that have been cycled, the method also includes:

The number of cycles in which the frame number of the system frame has been cycled from the frame number initialization time of the system frame to the specific system frame is not the cycle from the frame number initialization time of the system frame to the current time when the frame number of the system frame has been cycled. In the case of the number, the number of cycles in which the frame number of the system frame is cycled from the initialization of the frame number of the received system frame to the specific system frame is corrected.

Specifically, the foregoing modification may be based on comparing the air interface day time information received this time with the previously received air interface day time information, and comparing the frame numbers of the specific system frames corresponding to the current SFN and air interface time information to determine whether it is necessary. Correct the air interface time information. The TOD receiving module outputs the corrected air interface day information Tod_rx to the TOD recovery module.

FIG. 8 provides a method for correcting air interface time information, specifically including the following steps: Step 301, the LTE backhaul UE receives the air interface message, and obtains the air interface day time letter carried in step 302, determines whether it is the first time to receive the air interface time information Tod_tx, if yes, step 303 is performed, otherwise step 304 is performed;

Step 303: Determine whether the current SFN is greater than the frame number of the specific system frame corresponding to Tod_tx, if yes, go to step 305, otherwise go to step 307;

Step 304: Determine whether the value of the currently recorded Tod_rx is equal to the value of Tod_tx, if yes, execute step 305, otherwise perform step 306, which is for the case of transmitting Tod_tx multiple times in one SFN cycle;

Step 305: Assign the value of the Tod_rx obtained by the previous correction to Tod_tx;

Step 306, determining whether the current SFN is greater than the SFN when the Tod_tx received the previous time, if yes, executing step 305, otherwise performing step 307;

Step 307: Correcting the Tod_tx, that is, when the frame number of the specific system frame in the air interface time information is not in the same SFN cycle period as when the air interface time information is received, the Tod_tx needs to be corrected, and the TOD in the Tod_tx is to be corrected. The related information is corrected to the TOD information Tod_rx corresponding to the specific system frame in the current period. Specifically, for the case of transmitting the system time value of the specific system frame start time, TOD=Tod_tx in Tod_rx is 10.24s, and the time time information transmitted on the air interface is corresponding to the frame number of the specific system frame. In the case of the number of cycles N, N=N+1 in Tod_rx.

In the above embodiment, the received air interface time information is corrected, and the corrected air interface time information, that is, Tod_rx, is obtained, and the system time information corresponding to the current start time is restored, and Tod_rcvr is used to indicate:

Tod_rcvr=Tod_rx+Delta_SFN/l 00s

Delta_SFN indicates the difference between the frame number of the current system frame and the frame number of a specific system frame in this period. Because the pulse period of each system frame is 10ms, the time difference is Ddta_SFN/100s. Based on the above Tod_rcvr, the system time and PPS information can be recovered according to the Tod_rcvr and the local timing relationship.

In addition, for the case where the number of loop periods corresponding to the frame number of the specific system frame is transmitted on the air interface, the number of cycles in which the frame number of the system frame has been cycled from the frame number initialization time of the system frame to the current time, at this time, Tod_rcvr = 1024 * N + SFN, where SFN is the frame number of the current system frame. On the basis of the foregoing, the system time and PPS information may be further restored according to the Tod_rcvr and the local timing relationship, so as to achieve synchronization between the LTE backhaul UE and the LTE backhaul base station.

After the LTE backhaul UE acquires the foregoing system time information, it can be delivered to the remote base station equipment BTS that is connected to the cable, and the FE/GE connection established between the LTE backhaul UE and the BTS, and the LTE backhaul UE. The system time information can be transmitted between the BTS and the BTS by means of 1PPS+TOD. If the 1588 protocol is supported between the LTE backhaul UE and the BTS, the TOD can also be transmitted to the BTS through the 1588 event message.

The embodiment of the present invention further provides a clock synchronization processing device. FIG. 9 is a schematic structural diagram of Embodiment 1 of a clock synchronization processing device according to the present invention. The clock synchronization processing device may be disposed in an LTE backhaul base station, as shown in FIG. The device includes a first obtaining module 11 , an information generating module 12 and a first sending module 13 , wherein the first acquiring module 11 is configured to acquire system time information; and the information generating module 12 is configured to use the system time time information and the specific system frame. The information generates the air interface time information corresponding to the specific system frame, and the air interface time information corresponding to the specific system frame is used to transmit the system time information between the long term evolution backhaul base station and the long term evolution backhaul user equipment. The first sending module 13 And transmitting, to the long-term evolution backhaul user equipment, an air interface message including the air interface day time information corresponding to the specific system frame.

The clock synchronization processing apparatus provided by the foregoing embodiment of the present invention can realize the transmission of the system time and time by acquiring the system time and time information and converting it into the air interface time and time information transmitted on the air interface, thereby making the backhaul of the system using the LTE base station. In the case of an absolute time synchronization in the system.

In a specific embodiment of the present invention, the air interface time information is mainly the system time and the special time The frame number of the system frame is associated. For example, the air interface time information may include a system time value of a specific system frame start time, and the specific system frame may be between the long term evolution backhaul base station and the long term evolution backhaul user equipment. Pre-configured; or the air interface time information includes the frame number of the specific system frame, and the system day time value of the specific system frame start time, that is, the pre-configuration is not performed, but is transmitted simultaneously with the frame number of the specific system frame, as shown in the figure. 10, wherein the information generating module 12 may include a first information generating unit 121, configured to use the system time time information, the current system frame start time, the frame number of the current system frame, and The frame number of the specific system frame acquires a system time value of the specific system frame start time.

In addition, the air interface time information includes the number of cycles in which the frame number of the system frame has been cycled from the frame number initialization time of the system frame to the specific system frame, where the specific system frame may be in the long term evolution backhaul base station and long term evolution. The backhaul user equipment is pre-configured; or the air interface time information includes the frame number of the specific system frame, and the number of cycles in which the frame number of the system frame has been cycled from the frame number initialization time of the system frame to the specific system frame, that is, The frame number of a specific system frame is pre-configured, and is transmitted simultaneously with the number of cycles in which the above frame number has been cycled. In this case, the information generating module 12 may include a second information generating unit 122, configured to acquire the cycle according to the system time time information, the current system frame start time, and the cycle number of the frame number of the system frame. The number of cycles from which the frame number of the system frame has been cycled from the frame number initialization time of the system frame to the specific system frame.

The manner of transmitting the air interface time information between the LTE backhaul base station and the LTE backhaul UE may be carried in a manner of a high-level message or in an existing signaling message, for example, by means of a high-level message, as shown in the figure. 10, the above information generating module 12 includes a message encapsulating unit

123. The unit is configured to generate a daily time delivery message according to the air interface time information, where the daily time delivery message encapsulation includes a message header and a payload field, where the message header is used to represent the type of the time delivery message. The air interface day time information is located in the payload field.

Corresponding to the above embodiment, the present invention further provides a clock synchronization processing device disposed in an LTE backhaul UE, and FIG. 11 is a schematic structural diagram of a second embodiment of the clock synchronization processing device according to the present invention. As shown in FIG. 11, the apparatus includes a receiving module 21 and a second acquiring module 22, where the receiving module 21 is configured to receive, by the long-term evolution backhaul base station, an air interface message that includes air interface time information corresponding to a specific system frame, where the specific system is The air interface time information corresponding to the frame is generated by the long-term evolution backhaul base station according to the system time information and the specific system frame information, and is used to transmit system time information between the long-term evolution backhaul base station and the long-term evolution backhaul user equipment; The system time information is acquired and time synchronized according to the air interface day time information corresponding to the specific system frame.

In this embodiment, the clock synchronization processing device in the LTE backhaul UE converts the received air interface time information into system time information, which can synchronize the system clock in the case where the LTE base station performs backhaul.

In a specific embodiment, the air interface time information transmitted on the air interface may be that the air interface time information is associated with a specific system frame, and the specific air interface time information may be a system including a specific system frame start time. The time value of the day, or the number of cycles including the system frame number that has been cycled from the system frame number initialization time to the specific system frame. Due to the delay of the message being transmitted on the air interface, the transmission process of the above air interface message may have crossed an SFN cycle period, that is, the time zone information corresponding to the received specific system frame is the specific system frame of the previous SFN cycle period. It is necessary to correct the air interface time information.

Specifically, the air interface time information includes a system time value of a specific system frame start time, and the specific system frame is pre-configured between the long term evolution backhaul base station and the long term evolution backhaul user equipment; or the air interface day time information Include a frame number of a particular system frame, and a system time value of the specific system frame start time, as shown in FIG. 12, the apparatus further includes a first correcting module 23 for the particular system frame When the frame number of the current system frame is not in the frame number cycle period of the same system frame, the system time value of the received system frame start time is corrected.

Or the air interface time information includes the number of cycles in which the frame number of the system frame has been cycled from the frame number initialization time of the system frame to the specific system frame, and the specific system frame is a long-term evolution backhaul base station and a long-term evolution backhaul. Pre-configured between user equipments; or the air interface time information includes a specific system The frame number of the system frame, and the number of cycles from the frame number initialization time of the system frame to the frame number of the system frame in the specific system frame. In this case, the device further includes: a second correction module 24, The module is configured to: when the frame number initialization time of the self-system frame reaches a specific system frame, the number of cycles in which the frame number of the system frame has been cycled is not the frame number of the system frame from the frame number initialization time of the system frame to the current time When the number of cycles has been cycled, the number of cycles in which the frame number of the system frame has been cycled from the initialization of the frame number of the received system frame to the specific system frame is corrected.

Further, in the embodiment of the present invention, the clock synchronization processing apparatus may further include a second sending module 25, where the second sending module 25 is configured to send a notification message including the system time and time information to the user side transceiver device, and this embodiment The user side device in the middle refers to a base station that is connected to the long term evolution backhaul user equipment and needs to provide a backhaul for the long term evolution backhaul base station.

The embodiment of the present invention further provides a communication system, including a long-term evolution backhaul base station, a long-term evolution backhaul user equipment, and a base station that is connected to a long-term evolution backhaul user equipment and needs to provide a backhaul for a long-term evolution backhaul base station, where the long-term evolution backhaul base station includes In the above clock synchronization processing apparatus, the long term evolution backhaul user equipment includes the above clock synchronization processing apparatus. In the technical solution provided by the foregoing embodiment, the LTE base station performs backhaul, and the acquired system time time information is converted into air interface day time information in the LTE backhaul base station, and is transmitted to the LTE backhaul UE, and the LTE backhaul UE is used. It is restored, the system time information is obtained, and transmitted to the remote base station connected thereto, which can achieve absolute time synchronization of the remote base station. Moreover, the method for associating the system time information with the frame number of the specific system frame can reduce the requirement for real-time transmission, and transmit the air interface time and time information through the high-level message or the existing signaling bearer, thereby effectively reducing the pair. The impact of the air interface process.

A person skilled in the art can understand that all or part of the steps of implementing the above method embodiments may be completed by using hardware related to the program instructions. The foregoing program may be stored in a computer readable storage medium, and the program is executed when executed. The foregoing steps include the steps of the foregoing method embodiments; and the foregoing storage medium includes: a medium that can store program codes, such as a ROM, a RAM, a magnetic disk, or an optical disk.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions described in the foregoing embodiments may be modified or equivalently substituted for some of the technical features. The modifications and substitutions of the present invention do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

Rights request

A clock synchronization processing method, comprising:

Obtain system time information;

2. The clock synchronization processing method according to claim 1, wherein the air interface time information includes a system time value of a specific system frame start time, and the specific system frame is in the long term evolution backhaul. Pre-configured between the base station and the long-term evolution backhaul user equipment;

And generating the air interface time information corresponding to the specific system frame according to the system time information and the specific system frame information, and at least:

Obtaining a system time value of the specific system frame start time according to the system time time information, the current system frame start time, the frame number of the current system frame, and the frame number of the specific system frame.

The clock synchronization processing method according to claim 1, wherein the air interface time information includes a frame number of a specific system frame, and a system time value of the specific system frame start time, the basis The system time information and the specific system frame information generate air interface time and time information corresponding to the specific system frame, and at least include:

The clock synchronization processing method according to claim 1, wherein the air interface time information includes a number of cycles in which a frame number of the system frame has been cycled from a frame number initialization time of the system frame to a specific system frame. And the specific system frame is pre-configured between the long term evolution backhaul base station and the long term evolution backhaul user equipment; The generating the air interface time and time information corresponding to the specific system frame according to the system time information and the specific system frame information, at least:

Obtaining, according to the system time time information, the current system frame start time, and the cycle number of the frame number of the system frame, the period of the frame number of the system frame from the initialization time of the frame number of the system frame to the specific system frame number.

The clock synchronization processing method according to claim 1, wherein the air interface time information includes a frame number of a specific system frame, and a system frame from a frame number initialization time of the system frame to a specific system frame. The number of cycles in which the frame number has been cycled, and the generating the air interface time and time information corresponding to the specific system frame according to the system time information and the specific system frame information, at least:

The clock synchronization processing method according to claim 1, wherein the transmitting the air interface message including the air interface time and time information to the long-term evolution backhaul user equipment comprises:

And generating, according to the air interface time information, a date transfer message, where the time transfer message includes a message header and a payload field, where the message header is used to represent the type of the time transfer message, the air interface time Information is located in the payload field;

An air interface message including the day time delivery message is sent to the long term evolution backhaul user equipment.

Transmitting, to the long term evolution backhaul user equipment, a radio resource control connection reconfiguration message including the air interface day time information, where the air interface day time information is encapsulated in an extension field of the radio resource control connection reconfiguration message; or

Transmitting, by the long term evolution backhaul user equipment, a dedicated radio resource control protocol signaling message including the air interface day time information; or A dedicated system information block message including the air interface day time information is transmitted to the long term evolution backhaul user equipment.

The clock synchronization processing method according to claim 1, further comprising: a long-term evolution backhaul user equipment receiving an air interface message including the air interface day time information corresponding to the specific system frame;

The long-term evolution backhaul user equipment obtains system day time information according to the air interface day time information corresponding to the specific system frame and performs time synchronization.

9. A clock synchronization processing method, comprising:

The clock synchronization processing method according to claim 9, wherein the air interface time information includes a system time value of a specific system frame start time, and the specific system frame is a long-term evolution backhaul base station and Pre-configured between long-term evolution backhaul user equipment;

Or the air interface time information includes a frame number of a specific system frame, and a system time value of the specific system frame start time;

Or the air interface time information includes a number of cycles in which the frame number of the system frame has been cycled from a frame number initialization time of the system frame to a specific system frame, and the specific system frame is a long-term evolution backhaul base station and a long-term evolution backhaul. Pre-configured between user equipments;

Or the air interface time information includes a frame number of a specific system frame, and a number of cycles in which the frame number of the system frame has been cycled from the frame number initialization time of the system frame to the specific system frame.

The clock synchronization processing method according to claim 10, wherein the method Also includes:

Correcting the system time value of the received specific system frame start time when the frame number of the specific system frame is not in the frame number cycle period of the same system frame as the frame number of the current system frame; or The number of cycles in which the frame number of the system frame has been cycled from the frame number initialization time of the system frame to the specific system frame is not the number of cycles in which the frame number of the system frame has been cycled from the frame number initialization time of the system frame to the current time. At the same time, the number of cycles in which the frame number of the system frame is cycled from the initialization of the frame number of the received system frame to the specific system frame is corrected.

The clock synchronization processing method according to claim 9, further comprising: transmitting a notification message including the system time and time information to the user side transceiver device.

13. A clock synchronization processing device, comprising:

The first ear is used to obtain system time information;

An information generating module, configured to generate air interface time information corresponding to a specific system frame according to the system time information and the specific system frame information, where the air interface day time information corresponding to the specific system frame is used in the long term evolution backhaul base station and Long-term evolution backhaul user equipment transfer system time information;

And a first sending module, configured to send, to the long term evolution backhaul user equipment, an air interface message including the air interface day time information corresponding to the specific system frame.

14. The clock synchronization processing apparatus according to claim 13, wherein the air interface time information includes a system time value of a specific system frame start time, and the specific system frame is in the long term evolution backhaul. The base station is configured with a long-term evolution backhaul user equipment; or the air interface time information includes a frame number of a specific system frame, and a system time value of the specific system frame start time, where the information generating module includes:

a first information generating unit, configured to acquire, according to the system time time information, a current system frame start time, a frame number of a current system frame, and a frame number of the specific system frame, a system date of the specific system frame start time Time value.

The clock synchronization processing device according to claim 13, wherein the air interface The time information includes the number of cycles in which the frame number of the system frame has been cycled from the frame number initialization time of the system frame to the specific system frame, and the specific system frame is in the long term evolution backhaul base station and the long term evolution backhaul user equipment. Or pre-configured; or the air interface time information includes a frame number of a specific system frame, and a number of cycles in which the frame number of the system frame has been cycled from a frame number initialization time of the system frame to a specific system frame, The information generation module includes:

a second information generating unit, configured to acquire, according to the system time time information, the current system frame start time, and the cycle period of the frame number of the system frame, the system frame time from the frame number initialization time of the self system frame to the specific system frame time The number of cycles in which the frame number has been cycled.

The clock synchronization processing device according to claim 13, wherein the information generation module comprises:

a message encapsulating unit, configured to encapsulate a generated daily time delivery message according to the air interface time information, where the daily time delivery message includes a message header and a payload field, where the message header is used to represent the type of the time delivery message, The air interface time information is located in the payload field.

17. A clock synchronization processing apparatus, comprising:

a receiving module, configured to receive, by the long-term evolution backhaul base station, an air interface message that includes air interface time information corresponding to a specific system frame, where the air interface time information corresponding to the specific system frame is a long-term evolution backhaul base station according to system time time information and specific System frame information is generated and used to transmit system time information between the long term evolution backhaul base station and the long term evolution backhaul user equipment;

And a second acquisition block, configured to acquire system time information according to the air interface day time information corresponding to the specific system frame and perform time synchronization.

The clock synchronization processing device according to claim 17, wherein the air interface time information includes a system time value of a specific system frame start time, and the specific system frame is a long-term evolution backhaul base station. And pre-configuring with the LTE backhaul user equipment; or when the air interface time information includes a frame number of a specific system frame, and a system time value of the specific system frame start time, the apparatus further includes: a first correction module, configured to: when the frame number of the specific system frame and the frame number of the current system frame are not in a frame number cycle period of the same system frame, a system time time of the received specific system frame start time The value is corrected;

Or, the air interface time information includes a number of cycles in which a frame number of the system frame has been cycled from a frame number initialization time of the system frame to a specific system frame, and the specific system frame is a long-term evolution backhaul base station and a long-term Pre-configuring between the evolved backhaul user equipments; or the period in which the air interface time information includes the frame number of the specific system frame, and the frame number of the system frame from the initialization time of the frame number of the system frame to the specific system frame The device further includes:

a second correction module, configured to: when the frame number initialization time of the self-system frame reaches a specific system frame, the number of cycles in which the frame number of the system frame has been cycled is not from the frame number initialization time of the system frame to the current time system frame When the frame number has been cycled, the number of cycles in which the frame number of the system frame has been cycled from the initialization of the frame number of the received system frame to the specific system frame is corrected.

The clock synchronization processing device according to claim 17, further comprising: a second sending module, configured to send a notification message including the system time and time information to the user side transceiver device.

20. A communication system, comprising a long term evolution backhaul base station and a long term evolution backhaul user equipment, wherein the long term evolution backhaul base station comprises the clock synchronization processing apparatus according to any one of claims 13-16, the long term evolution backhaul The user equipment comprises the clock synchronization processing device of any of claims 17-19.