WO2010099724A1

WO2010099724A1 - Method and device for correcting frequency offset

Info

Publication number: WO2010099724A1
Application number: PCT/CN2010/070761
Authority: WO
Inventors: 秦一平; 蒋培刚; 吴和兵
Original assignee: 华为技术有限公司
Priority date: 2009-03-03
Filing date: 2010-02-26
Publication date: 2010-09-10
Also published as: CN101547062A; CN101547062B

Abstract

A method and device for correcting frequency offset is disclosed in the embodiments of the present invention, which belongs to the field of communications. The method comprises the steps of: receiving current packet data, and obtaining frequency domain data and pilot frequency data of a user in the current packet data according to the received current packet data; obtaining a frequency offset estimation result of the user of the current packet data according to the pilot frequency data of the user in the current packet data and a frequency offset correction result of the user of the packet data whose frequency offset has been already corrected; and correcting the frequency offset of the frequency domain data of the user in the current packet data according to the frequency offset estimation result. The device comprises a receiving module, an obtaining module and a frequency offset correction module. By adopting the feedback of the frequency offset correction result of the user of the packet data whose frequency offset has been already corrected to obtain the frequency offset correction result of the user of the current packet data, the complexity of Automatic Frequency Correction (AFC) is greatly reduced.

Description

频偏纠正方法和设备 Frequency offset correction method and device

本申请要求于 2009 年 03 月 03 日提交中国专利局、申请号为 200910079158. 1、发明名称为 "频偏纠正方法和设备" 的中国专利申请的优先权，其全部内容通过引用结合在本申请中。技术领域 The present application claims priority to Chinese Patent Application No. 200910079158, filed on March 3, 2009, the entire disclosure of which is hereby incorporated by reference. in. Technical field

本发明涉及通信领域，特别涉及一种频偏纠正方法和设备。背景技术 The present invention relates to the field of communications, and in particular, to a frequency offset correction method and apparatus. Background technique

3GPP ( 3rd Generation Partnership Project, 第三代合作伙伴计划）中， LTE ( Long Term Evolution, 长期演进 )项目是近两年来 3GPP启动的最大的新技术研发项目，这种以 OFDM ( Orthogonal Frequency Division Multiple Access, 正交频分复用） /FDMA ( Frequency Division Multiple Access, 频分复用）为核心的技术可以被看作 "准 4G" 技术。 In the 3GPP (3rd Generation Partnership Project), the LTE (Long Term Evolution) project is the largest new technology development project initiated by 3GPP in the past two years. This type of OFDM (Orthogonal Frequency Division Multiple Access) , Orthogonal Frequency Division Multiplexing) /FDMA (Frequency Division Multiple Access) technology can be regarded as "quasi 4G" technology.

OFDM是 MCM ( Multi-Carrier Modulation, 多载波调制）的一种。其主要思想是：将信道分成若干正交子信道，将高速数据信号转换成并行的低速子数据流，调制到每个子信道上进行传输。正交信号可以通过在接收端采用相关技术来分开，这样可以減少子信道之间的相互干扰。每个子信道上的信号带宽小于信道的相关带宽，因此每个子信道上的可以看成平坦性衰落，从而可以消除符号间干扰。而且由于每个子信道的带宽仅仅是原信道带宽的一小部分，信道均衡变得相对容易。 OFDM可以结合分集、时空编码、干扰和信道间干扰抑制以及智能天线技术，最大限度地提高***性能。但是， OFDM对频率偏移较为敏感，而频率偏移会导致时域样点产生相位旋转，使不同的 OFDM符号之间存在相位偏差，同时还会破坏 OFDM***子载波之间的正交性，从而恶化解调性能。因此，需要对频率偏移进行估计。 OFDM is a type of MCM (Multi-Carrier Modulation). The main idea is to divide the channel into several orthogonal subchannels, convert the high-speed data signals into parallel low-speed sub-data streams, and modulate them onto each sub-channel for transmission. The orthogonal signals can be separated by using related techniques at the receiving end, which can reduce mutual interference between subchannels. The signal bandwidth on each subchannel is less than the associated bandwidth of the channel, so that each subchannel can be seen as flat fading, thereby eliminating intersymbol interference. And since the bandwidth of each subchannel is only a small fraction of the original channel bandwidth, channel equalization becomes relatively easy. OFDM can combine diversity, space-time coding, interference and inter-channel interference suppression, and smart antenna technology to maximize system performance. However, OFDM is sensitive to frequency offset, and frequency offset causes phase rotation of time domain samples, which causes phase deviation between different OFDM symbols, and also destroys orthogonality between OFDM system subcarriers. Thereby deteriorating performance is deteriorated. Therefore, the frequency offset needs to be estimated.

现有技术中的 AFC ( Automatic Frequency Correction, 自动频偏纠正）方法，采用 CP ( Cyclic Prefix, 循环前缀）频偏估计结合导频参考信号频偏估计的方法对频率偏移进行估计。其中 , 时域的 CP通过 DFT ( Discrete Fourier Transform, 离散傅立叶变换）分离出用户的频域信号，与用户该 OFDM符号中 FFT ( Fast Fourier Transform, 快速傅立叶变换）符号部分的频域数据之间的相位差别就可以求出相应的频偏。由于 CP是数据 FFT符号的部分重复，并且 CP部分和数据重复的部分在时域上相隔不大，利用这种重复特性可以涵盖较大的频偏范围。 In the prior art, an AFC (Automatic Frequency Correction) method uses a CP (Cyclic Prefix) frequency offset estimation combined with a pilot reference signal frequency offset estimation method to estimate the frequency offset. The time domain CP separates the user's frequency domain signal by DFT (Discrete Fourier Transform), and the frequency domain data of the FFT (Fast Fourier Transform) symbol part of the OFDM symbol. Phase difference To find the corresponding frequency offset. Since the CP is a partial repetition of the data FFT symbol, and the CP portion and the data-repeating portion are not spaced apart in the time domain, this repetition characteristic can be used to cover a larger frequency offset range.

但是本发明的发明人在研究上述方案的过程中发现：该方案需要将时域的 CP信号保存下来，并对 CP额外作 DFT处理，复杂度较高；并且，时域的 CP 受到的影响较多，定时偏差会导致 CP有效长度缩短， CP中包含多个用户的信号，特别是 CP并不是完整的 FFT符号，所以 CP信号变换到频域不同用户的信号会发生干扰。因此采用 CP估计频偏精度较差，即使和导频参考信号结合来估计，错误概率还是比较大。发明内容 However, the inventor of the present invention found in the process of studying the above scheme: the scheme needs to save the CP signal in the time domain, and additionally performs DFT processing on the CP, and the complexity is high; and the CP in the time domain is affected more. Many, the timing offset will cause the effective length of the CP to be shortened. The CP contains signals of multiple users. In particular, the CP is not a complete FFT symbol, so the signal of the CP signal is changed to different users in the frequency domain. Therefore, the CP is used to estimate the accuracy of the frequency offset, and even if combined with the pilot reference signal, the error probability is relatively large. Summary of the invention

为了降低频偏纠正的复杂度，并保证***可靠、安全的工作，本发明实施例提供了一种频率纠正方法和设备。 In order to reduce the complexity of frequency offset correction and to ensure reliable and safe operation of the system, an embodiment of the present invention provides a frequency correction method and apparatus.

一方面，提供了一种频偏纠正方法，包括： In one aspect, a frequency offset correction method is provided, including:

接收当前分组数据，根据所述接收到的当前分组数据获取用户在当前分组数据中的频域数据和导频数据； Receiving current packet data, and acquiring frequency domain data and pilot data of the user in the current packet data according to the received current packet data;

根据所述用户在当前分组数据中的导频数据以及所述用户在已经过频偏纠正的分组数据中的频偏纠正结果，获得所述用户在当前分组数据中的频偏估计结果； Obtaining a frequency offset estimation result of the user in the current packet data according to the pilot data of the user in the current packet data and the frequency offset correction result of the user in the packet data that has been subjected to the frequency offset correction;

根据所述频偏估计结果对所述用户在当前分组数据中的频域数据进行频偏纠正 Perform frequency offset correction on the frequency domain data of the user in the current packet data according to the frequency offset estimation result.

另一方面，提供了一种网络侧设备，包括： In another aspect, a network side device is provided, including:

接收模块，用于接收当前分组数据，根据所述接收到的当前分组数据获取用户在当前分组数据中的频域数据和导频数据； a receiving module, configured to receive current packet data, and obtain frequency domain data and pilot data of the user in the current packet data according to the received current packet data;

获得模块，用于根据所述用户在当前分组数据中的导频数据以及所述用户在已经过频偏纠正的分组数据中的频偏纠正结果，获得所述用户在当前分组数据中的频偏估计结果； And an obtaining module, configured to obtain, according to the pilot data of the user in the current packet data and the frequency offset correction result of the user in the packet data that has been subjected to the frequency offset correction, obtaining the frequency offset of the user in the current packet data Estimated result;

频偏纠正模块，用于根据所述获得模块获得的频偏估计结果对所述用户在当前分组数据中的频域数据进行频偏糾正。用户在当前分组数据中的导频数据，获得较为准确的频偏估计结果，并根据获得的频偏糾正结果对用户在当前分组数据中的频域数据进行频偏纠正。本发明实施例的提供的技术方案运算复杂度较小，能够保证***可靠、有效的工作。附图说明 And a frequency offset correction module, configured to perform frequency offset correction on the frequency domain data of the user in the current packet data according to the frequency offset estimation result obtained by the obtaining module. The pilot data in the current packet data of the user obtains a more accurate frequency offset estimation result, and is obtained according to The obtained frequency offset correction result performs frequency offset correction on the frequency domain data of the user in the current packet data. The technical solution provided by the embodiment of the invention has less computational complexity and can ensure reliable and effective operation of the system. DRAWINGS

图 1是本发明实施例一提供的频率纠正方法流程图； 1 is a flowchart of a frequency correction method according to Embodiment 1 of the present invention;

图 2是本发明实施例一提供的接收端接收到的信号示意图； 2 is a schematic diagram of a signal received by a receiving end according to Embodiment 1 of the present invention;

图 3是本发明实施例二提供的频率糾正方法流程图； 3 is a flowchart of a frequency correction method according to Embodiment 2 of the present invention;

图 4是本发明实施例二提供的频偏区间划分的示意图； 4 is a schematic diagram of frequency offset interval division according to Embodiment 2 of the present invention;

图 5是本发明实施例二提供的频偏区间的子区间的划分示意图； 5 is a schematic diagram of dividing a subinterval of a frequency offset interval according to Embodiment 2 of the present invention;

图 6是本发明实施例三提供的网络侧设备结构示意图； 6 is a schematic structural diagram of a network side device according to Embodiment 3 of the present invention;

图 7是本发明实施例三提供的获得模块的结构示意图； 7 is a schematic structural diagram of an obtaining module according to Embodiment 3 of the present invention;

图 8是本发明实施例三提供的候选频偏估计结果单元的结构示意图。具体实施方式 FIG. 8 is a schematic structural diagram of a candidate frequency offset estimation result unit according to Embodiment 3 of the present invention. detailed description

为使本发明的目的、技术方案和优点更加清楚，下面将结合附图对本发明实施方式作进一步地详细描述。实施例一 The embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. Embodiment 1

参见图 1 , 本发明实施例提供了一种频偏纠正方法，该方法主要包括： 101 : 接收当前分组数据，根据接收到的当前分组数据获取用户在当前分组数据中的频域数据和导频数据； Referring to FIG. 1, an embodiment of the present invention provides a frequency offset correction method, where the method mainly includes: 101: receiving current packet data, and acquiring frequency domain data and pilots of a user in current packet data according to the received current packet data. Data

参见图 2，每个分组可以由若干个 OFDM符号组成，导频数据分配在其中少数的 OFDM符号内，最近的两个包含有导频数据的 OFDM符号之间间隔 P 个 OFDM符号。 Referring to FIG. 2, each packet may be composed of a number of OFDM symbols, pilot data is allocated among a small number of OFDM symbols, and the last two OFDM symbols including pilot data are spaced apart by P OFDM symbols.

102: 根据该用户在当前分组数据中的导频数据以及该用户在已经过频偏纠正的分组数据的频偏纠正结果，获得该用户在当前分组数据中的频偏估计结果；已经过频偏纠正的分组数据可以包括：在接收当前分组数据之前，接收到的任意一组分组数据，根据该分组数据中各个用户的频偏估计结果对该分组数据中的各个用户分别进行了频偏糾正。 Step 102: Obtain a frequency offset estimation result of the user in the current packet data according to the pilot data of the user in the current packet data and the frequency offset correction result of the packet data that the user has corrected by the frequency offset; The corrected packet data may include: any set of packet data received before receiving the current packet data, and performing frequency offset correction on each user in the packet data according to a frequency offset estimation result of each user in the packet data.

频偏纠正结果可以包括 CRC ( Cyclic Redundancy Check, 循环冗余码校验 ) 反馈，也可以是其他能够标识频偏纠正后的数据正确与否的结果。 The frequency offset correction result may include a CRC (Cyclic Redundancy Check) Feedback can also be the result of other data that can identify the correctness of the frequency offset correction.

103: 根据频偏估计结果对该用户在当前分组数据中的频域数据进行频偏糾正。合用户在当前分组数据中的导频数据，获得较为准确的频偏估计结果，并根据获得的频偏估计结果对用户在当前分组数据中的频域数据进行频偏纠正。本发明实施例的技术方案运算复杂度较小，能够保证***可靠、有效的工作。实施例二 103: Perform frequency offset correction on the frequency domain data in the current packet data of the user according to the frequency offset estimation result. The pilot data in the current packet data is combined with the user to obtain a more accurate frequency offset estimation result, and the frequency offset data of the user in the current packet data is frequency-corrected according to the obtained frequency offset estimation result. The technical solution of the embodiment of the invention has less computational complexity and can ensure reliable and efficient operation of the system. Embodiment 2

本发明实施例提供了一种频偏纠正方法，以发送端为移动终端、接收端为基站为例，参见图 3，该方法包括： An embodiment of the present invention provides a frequency offset correction method, where the transmitting end is a mobile terminal and the receiving end is a base station. Referring to FIG. 3, the method includes:

301 : 基站接收移动终端通过多个正交的子载波发送的时域数据； 301: The base station receives time domain data that is sent by the mobile terminal by using multiple orthogonal subcarriers.

这里需要说明的是，基站接收移动终端将调制在单载波上的高速串行数据流，分成多路低速的数据流，调制到多个正交的子载波上并行发送的时域数据。个分组可以由若干个 OFDM符号组成，导频数据分配在其中少数的 OFDM符号内，最近的两个包含有导频数据的 OFDM符号之间间隔 P个 OFDM符号；其中，一个 OFDM符号由 CP和 FFT样点组成。 CP的长度为 N_cp, FFT样点的数量为 N_FFT, —个 OFDM符号的长度 =N_ep+N_FFT。将时域数据以分组为单位进行发送的好处是：每一个分组的数据量比较小，比起连续发送全部 OFDM符号来说，基站以一个分组为单位进行频偏纠正时，处理的数据量会很大程度地降低；同时，基站以一个分组为单位进行频偏纠正，每个分组的频偏纠正结果都可以对下一分组的频偏糾正起到提示和帮助作用，减少了连续纠正全部 OFDM符号所造成的定时误差。 It should be noted that the base station receives the high-speed serial data stream modulated by the mobile terminal on a single carrier, divides into multiple low-speed data streams, and modulates the time-domain data transmitted in parallel on multiple orthogonal sub-carriers. The packets may be composed of a number of OFDM symbols, the pilot data is allocated among a few OFDM symbols, and the last two OFDM symbols containing pilot data are separated by P OFDM symbols; wherein, one OFDM symbol is composed of CP and FFT sample composition. The length of the CP is N _cp , the number of FFT samples is N _FFT , and the length of one OFDM symbol = N _ep + N _FFT . The advantage of transmitting time domain data in units of packets is: The amount of data per packet is relatively small. When the base station performs frequency offset correction in units of one packet, compared to continuously transmitting all OFDM symbols, the amount of data processed will be At the same time, the base station performs frequency offset correction in units of one packet, and the frequency offset correction result of each packet can prompt and help the frequency offset correction of the next packet, reducing continuous correction of all OFDM. Timing error caused by symbols.

302: 荻取每个用户在当前分组数据中的频域数据和导频数据； 302: Extract frequency domain data and pilot data of each user in current packet data;

该步骤中，基站接收到移动终端发送的以分组为单位的时域数据，将接收到的当前分组的时域数据中的 CP取出后丢弃，将 FFT样点进行 FFT变换及用户分离，得到每一个用户的在当前分组数据中的频域数据和导频数据。 In this step, the base station receives the time domain data sent by the mobile terminal in units of packets, takes out the CP in the received time domain data of the current packet, discards the CP, and performs FFT conversion and user separation to obtain an FFT sample. Frequency domain data and pilot data of a user in current packet data.

需要说明的是，将接收到的当前分组的时域数据中的 CP取出后丢弃，可以大大降低整个频偏估计过程的运算复杂度；使用 FFT样点进行 FFT变换用户分离，可以适当降低多用户之间的干扰影响。 It should be noted that the CP in the received time domain data of the current packet is discarded and discarded, which can greatly reduce the computational complexity of the entire frequency offset estimation process; Therefore, the interference effect between multiple users can be appropriately reduced.

本实施例以第 m个用户在当前分组的频域数据和导频数据为例。 In this embodiment, the frequency domain data and pilot data of the current group of the mth user are taken as an example.

其中，将基站接收到的频域上第个子载波中的第 r个 OFDM符号中的频域数据表示为 R (k， r); The frequency domain data in the rth OFDM symbol in the first subcarrier in the frequency domain received by the base station is represented as R (k, r);

如果频域上第 A个子载波中的第《个 OFDM符号中包括导频数据，则该导频数据可以表示为 RM ")，其中 =0， 1， …… K-1, 其中 ^是导频数据的总数。 If pilot data is included in the first OFDM symbol of the Ath subcarrier in the frequency domain, the pilot data may be represented as RM "), where = 0, 1, ... K-1, where ^ is the pilot The total number of data.

303: 对第 m个用户的当前分组的导频数据进行信道冲击响应系数的估计，得到信道冲击响应系数的估计值； 303: Perform estimation of a channel impulse response coefficient on pilot data of a current group of the mth user, and obtain an estimated value of a channel impulse response coefficient;

本发明实施例以 LS (Least Square, 最小二乘）估计的方法获得信道冲击响应系数的估计值为例，此外，还可以应用最大似然估计、 DFT变换域信道估计等方法获得信道冲击响应系数，其过程与 LS估计的过程基本相同，在此不做赘述。 In the embodiment of the present invention, an estimation result of a channel impulse response coefficient is obtained by using an LS (Least Square) estimation method. In addition, a maximum likelihood estimation, a DFT transform domain channel estimation method, etc. may be applied to obtain a channel impulse response coefficient. The process is basically the same as the process of LS estimation, and will not be described here.

第 A个子载波中的第《个 OFDM符号中导频数据的信道冲击响应系数的估计值 H« (k, n)可以表示为： The estimated value H« (k, n) of the channel impulse response coefficient of the pilot data in the "A OFDM symbol" of the A-th subcarrier can be expressed as:

H_LS (k, n) 1， ··.··. K-lH _LS (k, n) 1, ·····. Kl

其中， S_∞ (A：，《)是指移动终端发送的未经过信道冲击的导频参考信号，对于基站和移动终端来说， S_RS ( k, n)是双方都已知的。 S*_M ik, n)表示 S«_s ik, n) 的共轭。

Wherein, S _∞ (A:, ") refers to a pilot reference signal transmitted by the mobile terminal without channel impact, and for the base station and the mobile terminal, S _RS ( k, n) is known to both parties. S* _M ik, n) represents the conjugate of S« _s ik, n).

由于移动终端发送的导频参考信号一般有 |5^( 《)|²=1，所以上式可以简化为： Since the pilot reference signal transmitted by the mobile terminal generally has |5^(")| ² =1, the above formula can be simplified as:

H_LS ( k, n) = R^Ck^ S_R*_S(k,n) 0, 1, …… -1 H _LS ( k, n) = R^Ck^ S _R * _S (k,n) 0, 1, ...... -1

304: 根据当前分组中相邻最近的两个导频数据的信道冲击响应系数的估计值获取第 m个用户的当前分组的频偏估计值； 304: Obtain, according to an estimated value of channel impulse response coefficients of neighboring two nearest pilot data in the current packet, a frequency offset estimation value of a current packet of the mth user;

具体地，由于上一个导频数据所在的 OFDM符号的序号与本个导频数据所在的 OFDM符号的序号之间相差（P-1 )个 OFMD符号，因此，当上一个导频数据的信道冲击响应系数的 LS估计结果为 H _S n)时，相邻最近的导频数据的信道冲击响应系数的 LS估计结果为 H _LS ( k, n+P-l )。它们之间的相位差值为:

这里需要说明的是，设 r = fJH ( :,")' H_u( :," + P _ l) , 则 = "g/e{r}可以具体表示为 = arctan ( Γ的虚部 / Γ的实部）。 Specifically, since the sequence number of the OFDM symbol where the previous pilot data is located is different from the sequence number of the OFDM symbol in which the pilot data is located (P-1) OFMD symbols, when the channel impact of the previous pilot data When the LS estimation result of the response coefficient is H _S n), the nearest neighbor pilot number The LS estimation result of the channel impulse response coefficient is H _LS ( k, n+Pl ). The phase difference between them is:

What needs to be explained here is that if r = fJH ( :, ") ' H _u ( :, " + P _ l) , then = "g / e{r} can be specifically expressed as = arctan ( imaginary part / Γ Real part).

其次，根据相位差值^ 计算第 m个用户的当前分组的实际频偏值的小数频偏估计值，这里需要说明的是，本实施例中以小数频偏估计值为例，其他计算频偏估计值的方法与小数频偏估计值的方法基本类似，在此不做伴述。 Secondly, the fractional frequency offset estimation value of the actual frequency offset value of the current group of the mth user is calculated according to the phase difference ^, and it should be noted that, in this embodiment, the fractional frequency offset estimation value is used as an example, and other calculation frequency offsets are used. The method of estimating the value is basically similar to the method of estimating the fractional frequency offset, and will not be described here.

具体地，小数频偏估计值可以根据下式进行计算：

这里需要说明的是，由于一个分组内，相邻最近的两个导频数据之间相隔 P-1 个 OFDM符号，间隔较大，导致导频估计的频偏范围较小，不足以覆盖实际的频偏范围。因此，需要对导频估计所得到频偏估计值做进一步的处理才能得到第 m个用户的当前分组的实际频偏值。 Specifically, the fractional frequency offset estimation value can be calculated according to the following formula:

It should be noted that, because within a packet, the neighboring two pilot data are separated by P-1 OFDM symbols, and the interval is large, which results in a small frequency offset range of the pilot estimation, which is insufficient to cover the actual Frequency offset range. Therefore, the frequency offset estimation value obtained by the pilot estimation needs to be further processed to obtain the actual frequency offset value of the current packet of the mth user.

305: # ^居导频估计的第 m个用户的当前分组的频偏估计值，在频偏区间内获得实际频偏范围内第 m个用户的当前分组的候选频偏估计结果； 305: # ^the frequency offset estimation value of the current group of the mth user estimated by the pilot, and obtaining the candidate frequency offset estimation result of the current group of the mth user in the actual frequency offset range in the frequency offset interval;

该步骤中，使用导频估计的频偏估计范围作为一个频偏区间的大小，将用户的实际频偏范围划分为多个频偏区间，并根据 304 中计算得到的小数频偏估计值在其所属频偏区间中的位置，获得频偏区间中与小数频偏估计值所在的位置相同的第 m个用户的当前分组的候选频偏估计结果。 In this step, the frequency offset estimation range of the pilot estimation is used as the size of a frequency offset interval, and the actual frequency offset range of the user is divided into multiple frequency offset intervals, and the fractional frequency offset estimation value calculated according to 304 is in the The position in the frequency offset interval is obtained, and the candidate frequency offset estimation result of the current group of the mth user in the frequency offset interval which is the same as the position where the fractional frequency offset estimation value is located is obtained.

具体地频偏区间的划分可以包括： Specifically, the division of the frequency offset interval may include:

1 )基站根据上行***的载波频率 F和移动终端相对于基站的移动速度 V计算该上行***可能达到的实际频偏范围，其中，频偏正比于***载波频率 F和移动终端相对于基站的移动速度 V 1) The base station calculates an actual frequency offset range that the uplink system may reach according to the carrier frequency F of the uplink system and the moving speed V of the mobile terminal relative to the base station, where the frequency offset is proportional to the system carrier frequency F and the mobile terminal's movement relative to the base station Speed V

具体地，实际频偏可以达到的最大频偏范围为£ =^^ , 其中， C表示光速；那么，该上行***可能达到实际的最大频偏范围可以表示为Specifically, the maximum frequency offset that can be achieved by the actual frequency offset is £=^^, where C represents light. Speed; then, the uplink system may reach the actual maximum frequency offset range can be expressed as

2) 计算导频估计的频偏范围； 2) Calculate the frequency offset range of the pilot estimate;

由于该上行***为已知，那么移动终端和基站之间导频估计的频偏范围即 Since the uplink system is known, the frequency offset range of the pilot estimation between the mobile terminal and the base station is

£ £ £ £

为已知。设导频估计的频偏范围为，那么 s皿 =^ N Χ Δ/，其中 N_∞ Is known. Let the frequency offset of the pilot estimate be, then s dish =^ N Χ Δ/, where N _∞

2 2 N 是两个包含导频数据的 OFMD符号之间相隔的时域样点个数， Δ/是子载波之间的频率间隔。相应的，导频估计的频偏估计范围为 2 2 N is the number of time domain samples separated by two OFMD symbols containing pilot data, and Δ/ is the frequency interval between subcarriers. Correspondingly, the frequency offset estimation range of the pilot estimation is

3 ) 利用导频估计的频偏估计范围 , 将该上行***可能达到的 3) using the frequency offset estimation range of the pilot estimation, which may be achieved by the uplink system

2 2 twenty two

实际频偏范围 £_mffi划分为多个频偏区间； The actual frequency offset range £ _{mffi is} divided into multiple frequency offset intervals;

具体的划分方法可以包括： Specific division methods may include:

根据将 _max划分为 U个频偏区间，从频偏为零的位置为第一个频偏区间的中心点，分别向频偏为负，以及频偏为正的两个方向进行频偏区间的划分。划分后的频偏区间分别以 1， 2，， U进行标识。其中，由于频偏区间的这种划分方式，使得全部频偏区间是关于第一个频偏区间对称的，因此 U的取值为奇数。 U的值可以通过将^的值向上取整进行计算，当 U的计算值为偶数时，实际的 U值需要加 1。 According to the division of _max into U frequency offset intervals, the position from the frequency offset to zero is the center point of the first frequency offset interval, and the frequency offset is negative in both the frequency offset and the frequency offset is positive. Division. The divided frequency offset intervals are identified by 1, 2, and U, respectively. Among them, due to this division of the frequency offset interval, all the frequency offset intervals are symmetric about the first frequency offset interval, so the value of U is an odd number. The value of U can be calculated by rounding up the value of ^. When the calculated value of U is even, the actual U value needs to be increased by 1.

例如，叚设 U为 3 , 那么区间的划分可以如图 4所示，第一个频偏区间的第二个频偏区间位于第一个频偏区间的负向，范围是

ε max ε For example, if U is set to 3, then the division of the interval can be as shown in Fig. 4. The second frequency offset interval of the first frequency offset interval is in the negative direction of the first frequency offset interval, and the range is

ε max ε

第三个频偏区间位于第一个频偏区间的正向，范围是 The third frequency offset interval is in the positive direction of the first frequency offset interval, and the range is

2 2 例如，殳用户的实际频偏范围为 [- 10， 10]，导频估计的频偏估计范围为 [-3， 3] , 使用导频估计的频偏估计范围将用户的实际频偏范围进行频偏区间的划分，划分后的频偏区间可以表示为 [-10, -9]、 [-9, -3]、 [-3 , 3]、 [3 , 9]、 [9, 10]。twenty two For example, the actual frequency offset range of the user is [- 10, 10], the frequency offset estimation range of the pilot estimation is [-3, 3], and the frequency offset estimation range of the pilot estimation is used to perform the actual frequency offset range of the user. The division of the frequency offset interval, the divided frequency offset interval can be expressed as [-10, -9], [-9, -3], [-3, 3], [3, 9], [9, 10].

_设导频估计的第 m个用户的当前分组的小数频偏值为 1 , 落在 [-3, 3]这个频偏区间之内，才艮据 1在当前频偏区间的位置，比频偏区间的左端点大 4, 比频偏区间的右端点小 2，在全部频偏区间内获得实际频偏范围内第 m个用户的当前分组的频偏估计值，即： [-10， -9]、 [9， 10]这两个频偏区间中没有这样的频偏估计值， [-9, -3]频偏区间中的频偏估计值是 -5, [3, 9]频偏区间中的频偏估计值是 7。 _ Set the current fraction of the mth user of the pilot estimate to have a fractional frequency offset of 1 and fall within the frequency offset interval of [-3, 3], and then the position of the current frequency offset interval according to 1 The left end point of the partial interval is larger by 4, which is smaller than the right end point of the frequency offset interval by 2, and the frequency offset estimation value of the current group of the mth user in the actual frequency offset range is obtained in all frequency offset intervals, namely: [-10, - 9], [9, 10] There is no such frequency offset estimation value in the two frequency offset intervals, and the frequency offset estimation value in the [-9, -3] frequency offset interval is -5, [3, 9] frequency offset The frequency offset estimate in the interval is 7.

306: 根据已经过频偏纠正的分组数据的频偏纠正结果，选择使用哪个频偏区间的候选频偏估计结果作为频偏估计结果；反馈具体是指：已经过频偏糾正的分组数据的频偏纠正结果经过解调及译码后进行 CRC, 得到 CRC反馈。 306: According to the frequency offset correction result of the packet data that has been subjected to the frequency offset correction, select which frequency offset estimation candidate frequency offset estimation result is used as the frequency offset estimation result; the feedback specifically refers to: the frequency of the packet data that has been subjected to the frequency offset correction. After the partial correction result is demodulated and decoded, the CRC is performed to obtain CRC feedback.

如果已经过频偏纠正的分组数据的频偏纠正结果的 CRC反馈为错误，说明已经过频偏纠正的分組数据所采用的频偏估计结果不是第 m个用户的实际频偏值，已经过频偏纠正的分组数据所采用的频偏估计结果所属的频偏区间也不是第 m个用户的实际频偏值所在的频偏区间，所以使用与已经过频偏糾正的分组数据采用的频偏估计结果不同频偏区间的候选频偏估计结果作为当前分组数据的频偏估计结果，继续对分组数据进行频偏估计；这里需要说明的是，与已经过频偏纠正的分组数据采样的频偏估计结果所在的频偏区间不同的频偏区间可以有多个，选择时，可以随机选择不同的频偏区间，也可以是按照一定的顺序逐个选择。 If the CRC feedback of the frequency offset correction result of the packet data that has undergone the frequency offset correction is an error, the frequency offset estimation result used by the packet data that has undergone the frequency offset correction is not the actual frequency offset value of the mth user, and the frequency has been overfrequency. The frequency offset interval to which the frequency offset estimation result of the partial corrected packet data belongs is not the frequency offset interval in which the actual frequency offset value of the mth user is located, so the frequency offset estimation using the packet data that has been subjected to the frequency offset correction is used. As a result, the candidate frequency offset estimation results of different frequency offset intervals are used as the frequency offset estimation result of the current packet data, and the frequency offset estimation of the packet data is continued. Here, it is necessary to explain the frequency offset estimation of the packet data samples that have been subjected to the frequency offset correction. There may be multiple frequency offset intervals in the frequency offset interval where the result is located. When selecting, different frequency offset intervals may be randomly selected, or may be selected one by one in a certain order.

如果已经过频偏纠正的分组数据的频偏糾正结果的 CRC反馈为正确，说明已经过频偏纠正的分组数据所采用的频偏估计结果为第 m 个用户的实际频偏值，相应的，频偏估计结果所在频偏区间也是实际频偏值所属的频偏区间，因此继续使用已经过频偏纠正的分组数据采用的频偏估计结果所属的频偏区间，使用与已经过频偏糾正的分组数据采用的频偏估计结果相同频偏区间的候选频偏估计结果作为当前分组数据的频偏估计结果。 If the CRC feedback of the frequency offset correction result of the packet data that has undergone the frequency offset correction is correct, the frequency offset estimation result used by the packet data that has undergone the frequency offset correction is the actual frequency offset value of the mth user, correspondingly, The frequency offset interval in which the frequency offset estimation result is located is also the frequency offset interval to which the actual frequency offset value belongs. Therefore, the frequency offset interval to which the frequency offset estimation result used by the packet data that has been subjected to the frequency offset correction continues to be used, and the frequency offset correction used has been used. The frequency offset estimation result used by the packet data is the candidate frequency offset estimation result of the same frequency offset interval as the frequency offset estimation result of the current packet data.

需要说明的是：当 CRC反馈为正确后，基站会要求移动终端将原来的分组数据重传，以便用实际频偏值对全部分组数据进行频偏纠正。 It should be noted that: When the CRC feedback is correct, the base station will ask the mobile terminal to set the original packet. The data is retransmitted to perform frequency offset correction on all packet data with the actual frequency offset value.

这里还需要说明的是，在对第一组分组数据进行频偏纠正时，由于没有已经过频偏糾正的分组数据的频偏糾正结果的 CRC反馈，这时可以将频偏值设置为一个最有可能的值，或者初始化为零，即假设没有频偏。 It should also be noted here that when performing frequency offset correction on the first component group data, since there is no CRC feedback of the frequency offset correction result of the packet data that has been subjected to the frequency offset correction, the frequency offset value can be set to one of the most. There is a possible value, or initialized to zero, that is, there is no frequency offset.

307: 才艮据第 m个用户的当前分组的频偏值对第 m个用户的当前分组的频域数据进行频偏纠正； 307: Perform frequency offset correction on the frequency domain data of the current group of the mth user according to the frequency offset value of the current group of the mth user;

308: 将进行频偏糾正后的数据进行解调及译码，并将解调及译码后的数据作为频偏纠正结果为其他分组数据在候选频偏估计结果中选择频偏估计结果提供参考。 308: Demodulate and decode the data after frequency offset correction, and use the demodulated and decoded data as a frequency offset correction result to provide reference for selecting other frequency offset estimation results in candidate frequency offset estimation results. .

这里，频偏纠正结果可以为 CRC反馈，即将解调及译码后的数据进行 CRC , 得到 CRC反馈。 Here, the frequency offset correction result may be CRC feedback, that is, the demodulated and decoded data is subjected to CRC to obtain CRC feedback.

进一步地，为了保证频偏估计值发生跳变时，不影响实际频偏值的正确性，可以对每个频偏区间做进一步地划分： Further, in order to ensure that the frequency offset estimation value jumps without affecting the correctness of the actual frequency offset value, each frequency offset interval may be further divided:

A )将每个频偏区间进一步地划分为边界子区间和非边界子区间。 A) Each frequency offset interval is further divided into a boundary sub-interval and a non-boundary sub-interval.

当然，非边界子区间也可以划分为多个非边界小区间，每个小区间的频率范围不小于频偏的抖动范围。这里，抖动范围指的是频偏变化的最小值。 Of course, the non-boundary sub-interval can also be divided into multiple non-boundary cells, and the frequency range between each cell is not less than the jitter range of the frequency offset. Here, the jitter range refers to the minimum value of the frequency offset change.

参见图 5， U=3，可以将每个频偏区间分别划分成 A、 B、 C三个子区间，其中子区间 A属于非边界子区间，子区间 B、 C均属于边界子区间。 Referring to Fig. 5, U=3, each frequency offset interval can be divided into three sub-areas A, B, and C, wherein sub-interval A belongs to non-boundary sub-interval, and sub-intervals B and C belong to boundary sub-interval.

需要说明的是，子区间的划分并不做严格的规定，可以将区间进行三等分，也可以非边界子区间在整个区间中所占的比例高于边界子区间所占的比例。当然，还可以对非边界子区间进行进一步的划分，即将频偏区间划分为 4 个、 5 个……子区间，其中包括 2个边界子区间和多个非边界子区间。 It should be noted that the division of subintervals is not strictly defined, and the interval may be divided into three equal parts, or the proportion of the non-boundary subintervals in the entire interval may be higher than the proportion of the boundary subintervals. Of course, the non-boundary sub-interval can be further divided, that is, the frequency offset interval is divided into four, five ... sub-intervals, including two boundary sub-intervals and multiple non-boundary sub-intervals.

B ) 判断小数频偏估计值落在哪个已划分好的频偏区间中的子区间；如图 5所示，设估计出来的 s位于第一频偏区间的 A1子区间的 XI位置，相应的，在第二频偏区间的 A2子区间的 X2位置、第三频偏区间的 A3子区间的 X3位置，都是第 m个用户的当前分组的候选频偏估计结果。 B) judging which sub-interval of the fractional frequency offset estimation falls in the divided frequency offset interval; as shown in FIG. 5, it is assumed that the estimated s is located at the XI position of the A1 subinterval of the first frequency offset interval, correspondingly The X2 position of the A2 subinterval of the second frequency offset section and the X3 position of the A3 subinterval of the third frequency offset section are all candidate frequency offset estimation results of the current packet of the mth user.

具体的，参见图 5，假设实际频偏值开始是在频偏区间 2中的子区间 A2, 经过几个分组之后，实际频偏值可能已经变化到 C2的某个位置，由于 C2仍然属于频偏区间 2, 因此该值仍然可以作为实际频偏值，但如果实际频偏继续变化到 B3 , 那么由于计算出来的小数频偏估计值可以是 Bl、 B2、 B3中的一个，但如果这时锁定仍然认为实际频偏值位于频偏区间 2，那么就和实际频偏值有了偏差，所以需要对频偏区间进行跟踪，可以达到为以后的频偏估计提供参考值的作用。具体做法如下： Specifically, referring to FIG. 5, it is assumed that the actual frequency offset value starts in the sub-interval A2 in the frequency offset interval 2. After several packets, the actual frequency offset value may have changed to a certain position of C2, since C2 still belongs to the frequency. The interval is 2, so the value can still be used as the actual frequency offset value, but if the actual frequency offset continues to change to B3, then the calculated fractional frequency offset estimate can be one of Bl, B2, B3, but If the lock still assumes that the actual frequency offset value is in the frequency offset interval 2, then there is a deviation from the actual frequency offset value. Therefore, it is necessary to track the frequency offset interval, which can provide a reference value for the subsequent frequency offset estimation. The specific practices are as follows:

C )跟踪每一分组的实际频偏值，当实际频偏值从一个边界子区间变化到另一个边界子区间时，需要将频偏区间变更为与变化之前的边界子区间相邻的频偏区间，从而完成区间的变更，有效防止了频偏区间的抖动。 C) Tracking the actual frequency offset value of each packet. When the actual frequency offset value changes from one boundary subinterval to another, it is necessary to change the frequency offset interval to the frequency offset adjacent to the boundary subinterval before the change. The interval, thus completing the change of the interval, effectively prevents the jitter of the frequency offset interval.

当然，如果在确定了频偏区间之后， CRC 出现了连续错误，则需要重新进行频偏区间的搜索，直至 CRC反馈正确。 Of course, if there is a continuous error in the CRC after the frequency offset interval is determined, the search of the frequency offset interval needs to be performed again until the CRC feedback is correct.

具体的， g殳从 A1子区间开始，第 1个分组采用 (A1 )作为频偏估计结果，其中 _s (A1 )是 A1子区间的频偏估计值，经过解调及译码后，得到 CRC 反馈，如果收到的 CRC反馈为错误，则第 2个分组可以采用 s (A2)作为 A2 子区间的频偏估计结果，以此类推，直至收到的 CRC反馈为正确。当然，也可以只采用一个分组进行自动频偏糾正，即按照一定的顺序，用不同的频偏区间中的候选频偏估计结果对同一个分组中第 _m个用户的频域数据进行频偏纠正，直至收到的 CRC反馈为正确。 Specifically, g殳 starts from the A1 subinterval, and the first packet uses (A1) as the frequency offset estimation result, where _s (A1) is the frequency offset estimation value of the A1 subinterval, and after demodulation and decoding, the CRC is obtained. Feedback, if the received CRC feedback is an error, the second packet can use s (A2) as the frequency offset estimation result of the A2 subinterval, and so on, until the received CRC feedback is correct. Of course, it is also possible to perform automatic frequency offset correction using only one packet, that is, frequency offset correction of the frequency domain data of the _mth user in the same group by using the candidate frequency offset estimation results in different frequency offset intervals in a certain order. Until the received CRC feedback is correct.

需要说明的是，本发明实施例所提供的方法可用于 OFDM以外的***，只要参考信号的频偏估计范围较小，而实际频偏又较大的时候，都可以通过该方法进行频偏糾正。只需要以参考信号估计的频偏周期为区间，将实际频偏划分为若干个区间，然后在反馈 CRC的基上进行区间搜索和区间跟踪，从而锁定频偏区间，进而得到较为准确的频偏估计值。 It should be noted that the method provided by the embodiment of the present invention can be used in a system other than OFDM, and the frequency offset correction can be performed by using the method as long as the frequency offset estimation range of the reference signal is small and the actual frequency offset is large. . It is only necessary to divide the frequency offset period estimated by the reference signal into intervals, divide the actual frequency offset into several intervals, and then perform interval search and interval tracking on the basis of the feedback CRC, thereby locking the frequency offset interval, thereby obtaining a more accurate frequency offset. estimated value.

本发明实施例通过将用户可能达到的实际频偏范围划分为若干个频偏区间，结合用户在当前分组数据中的导频数据进行频偏估计，通过用户在已经过频偏纠正的分组数据中的频偏纠正结果，获得用户在当前分组中较为准确的频偏估计结果，从而达到对用户在当前分組数据中进行有效频偏糾正的效果。并且，通过有效的区间划分技术，保证频率跟踪的可靠性和稳定性，不会发生区间抖动。本发明实施例的技术方案运算复杂度较小，并且受定时误差、多用户干扰的影响较小，能够保证***可靠、有效的工作。实施例三 In the embodiment of the present invention, the actual frequency offset range that the user may reach is divided into a plurality of frequency offset intervals, and the frequency offset estimation is performed by using the pilot data in the current packet data by the user, and the user is in the packet data that has been corrected by the frequency offset. The frequency offset correction result obtains a more accurate frequency offset estimation result of the user in the current grouping, thereby achieving the effect of the user performing effective frequency offset correction in the current packet data. Moreover, through effective interval division techniques, the reliability and stability of frequency tracking are guaranteed, and no inter-area jitter occurs. The technical solution of the embodiment of the invention has less computational complexity and less influence by timing error and multi-user interference, and can ensure reliable and effective operation of the system. Embodiment 3

参见图 6 , 本发明实施例提供了一种网络侧设备，包括：接收模块 601，用于接收当前分组数据，根据接收到的当前分组数据获取用户在当前分组数据中的频域数据和导频数据； Referring to FIG. 6, an embodiment of the present invention provides a network side device, including: The receiving module 601 is configured to receive current packet data, and obtain frequency domain data and pilot data of the user in the current packet data according to the received current packet data.

获得模块 602 ,用于根据用户在当前分组数据中的导频数据以及用户在已经过频偏纠正的分组数据中的频偏纠正结果，荻得用户在当前分组数据中的频偏估计结果； The obtaining module 602 is configured to obtain a frequency offset estimation result of the user in the current packet data according to the pilot data of the user in the current packet data and the frequency offset correction result of the user in the packet data that has been subjected to the frequency offset correction;

频偏纠正模块 603，用于根据获得模块 602获得的频偏估计结果对用户在当前分组数据中的频域数据进行频偏糾正。 The frequency offset correction module 603 is configured to perform frequency offset correction on the frequency domain data in the current packet data of the user according to the frequency offset estimation result obtained by the obtaining module 602.

这里需要说明的是，当全部分组数据均未进行频偏纠正时，获得模块 602 还用于：设置用户在当前分组数据中频偏估计结果为零。 It should be noted that, when all the packet data are not subjected to frequency offset correction, the obtaining module 602 is further configured to: set the frequency offset estimation result of the user in the current packet data to be zero.

其中，参考前面方法实施例的相应描述，参见图 7,获得模块 602可以包括：频偏估计值获得单元 602A, 用于根据用户在当前分组数据中的导频数据获得用户在当前分组数据中的频偏估计值； Referring to FIG. 7 , the obtaining module 602 may include: a frequency offset estimation value obtaining unit 602A, configured to obtain, according to the pilot data of the user in the current packet data, the user in the current packet data. Frequency offset estimate;

候选频偏估计结果获得单元 602B , 用于根据用户在当前分组数据中的频偏估计值，获得用户在当前分组数据中的候选频偏估计结果； The candidate frequency offset estimation result obtaining unit 602B is configured to obtain a candidate frequency offset estimation result of the user in the current packet data according to the frequency offset estimation value of the user in the current packet data.

频偏估计结果获得单元 602C, 用于根据用户在已经过频偏纠正的分组数据中的频偏纠正结果，在候选频偏估计结果中选择用户在当前分组数据中的频偏估计结果。 The frequency offset estimation result obtaining unit 602C is configured to select a frequency offset estimation result of the user in the current packet data in the candidate frequency offset estimation result according to the frequency offset correction result of the user in the packet data that has been subjected to the frequency offset correction.

具体的 , 参考前面方法实施例的相应描述，频偏估计值获得单元 602A可以包括： Specifically, referring to the corresponding description of the foregoing method embodiment, the frequency offset estimation value obtaining unit 602A may include:

系数估计子单元，用于获取导频数据的信道冲击响应系数估计值；获得子单元，用于根据系数估计子单元中获得的相邻最近的两个导频信号的信道冲击响应系数估计值获取用户的当前分组的频偏估计值。 a coefficient estimation subunit, configured to obtain a channel impulse response coefficient estimation value of the pilot data; and an obtaining subunit, configured to obtain, according to the estimated channel impulse response coefficient of the neighboring two nearest pilot signals obtained in the coefficient estimation subunit The frequency offset estimate of the user's current packet.

具体的，参考前面方法实施例的相应描述，参见图 8，候选频偏估计结果单元 602B可以包括： Specifically, referring to the corresponding description of the foregoing method embodiment, referring to FIG. 8, the candidate frequency offset estimation result unit 602B may include:

频偏区间划分子单元 602B 1，用于将预知的用户的实际频偏范围划分为多个频偏区间； The frequency offset interval dividing sub-unit 602B 1 is configured to divide the actual frequency offset range of the predicted user into multiple frequency offset intervals;

获得子单元 602B2,用于根据用户在当前分组数据中的频偏估计值在其所属频偏区间内的位置，在多个频偏区间内获得多个与位置相同的候选频偏估计结果。 The obtaining sub-unit 602B2 is configured to obtain a plurality of candidate frequency offset estimation results with the same position in the plurality of frequency offset intervals according to the position of the frequency offset estimation value of the user in the current packet data within the frequency offset interval to which the user belongs.

其中，参考前面方法实施例的相应描述，频偏区间划分子单元 602B1用于：将导频估计的频偏估计范围作为一个频偏区间的大小，以频偏为零的位置作为第一个频偏区间的中点，分别向频偏为正及频偏为负两个方向将预知的用户的实际频偏范围划分为多个频偏区间。 With reference to the corresponding description of the foregoing method embodiment, the frequency offset interval dividing sub-unit 602B1 is used to: The frequency offset estimation range of the pilot estimation is taken as the size of one frequency offset interval, and the position with zero frequency offset is taken as the midpoint of the first frequency offset interval, and the frequency offset is positive and the frequency offset is negative. The actual frequency offset range of the predicted user is divided into a plurality of frequency offset intervals.

需要说明的是，当用户在已经过频偏纠正的分组数据中的频偏纠正结果为：馈时，频偏估计结果获得单元 602C用于：选择用户在当前分组数据中的候选频偏估计结果中与用户在已经过频偏糾正的分组数据的频偏估计结果属于不同频偏区间的候选频偏估计结果作为当前分组的频偏估计结果；选择用户在当前分组数据中的候选频偏估计结果中与用户在已经过频偏糾正的分组数据的频偏估计结果属于相同频偏区间的候选频偏估计结果作为当前分组的频偏估计结果。 It should be noted that, when the frequency offset correction result of the user in the packet data that has been subjected to the frequency offset correction is: feeding, the frequency offset estimation result obtaining unit 602C is configured to: select a candidate frequency offset estimation result of the user in the current packet data. The candidate frequency offset estimation result of the frequency offset estimation result of the packet data that has undergone frequency offset correction is the frequency offset estimation result of the current packet; and the candidate frequency offset estimation result of the user in the current packet data is selected. The candidate frequency offset estimation result that belongs to the same frequency offset interval as the frequency offset estimation result of the packet data that has been subjected to the frequency offset correction by the user is used as the frequency offset estimation result of the current packet.

进一步地，参考前面方法实施例的相应描述，候选频偏估计结果单元 602B 还可以包括： Further, referring to the corresponding description of the foregoing method embodiment, the candidate frequency offset estimation result unit 602B may further include:

子区间划分子单元，将每个频偏区间划分为边界子区间和非边界子区间；则获得子单元 602B2还用可以于： The sub-interval divides the sub-units, and each frequency-offset interval is divided into a boundary sub-interval and a non-boundary sub-interval; then the obtained sub-unit 602B2 is also used to:

当频偏估计值在其所属的频偏区间内从一个边界子区间改变至另一个边界子区间时，使用与改变前的边界子区间相邻的频偏区间中的频偏估计值作为当前分组的频偏值。 When the frequency offset estimation value changes from one boundary subinterval to another boundary subinterval within the frequency offset interval to which it belongs, the frequency offset estimation value in the frequency offset interval adjacent to the boundary subinterval before the change is used as the current grouping Frequency offset value.

需要说明的是，本实施例中的网络侧设备具体可以为基站。 It should be noted that the network side device in this embodiment may specifically be a base station.

本发明实施例提供的网络侧设备，通过用户在已经过频偏糾正的分组数据中的频偏糾正结果结合用户在当前分組数据中的导频数据，获得较为准确的频偏估计结果，并根据获得的频偏纠正结果对用户在当前分组数据中的频域数据进行频偏纠正。进一步地，本发明实施例通过将用户可能达到的实际频偏范围划分为若干个频偏区间，保证频率跟踪的可靠性和稳定性，不会发生区间抖动。本发明实施例的技术方案运算复杂度较小，并且受定时误差、多用户干扰的影响较小，能够保证***可靠、有效的工作。 The network side device provided by the embodiment of the present invention obtains a more accurate frequency offset estimation result by using the frequency offset correction result of the user in the packet data that has been subjected to the frequency offset correction and the pilot data in the current packet data, and according to The obtained frequency offset correction result performs frequency offset correction on the frequency domain data of the user in the current packet data. Further, in the embodiment of the present invention, the actual frequency offset range that the user may reach is divided into a plurality of frequency offset intervals to ensure the reliability and stability of the frequency tracking, and the interval jitter does not occur. The technical solution of the embodiment of the invention has less computational complexity, and is less affected by timing error and multi-user interference, and can ensure reliable and effective operation of the system.

本发明实施例可以利用软件实现，相应的软件程序可以存储在可读取的存储介质中，例如，路由器的硬盘、緩存或光盘中。 The embodiment of the invention can be implemented by using software, and the corresponding software program can be stored in the readable storage In the storage medium, for example, on the hard disk, cache, or disc of the router.

以上所述仅为本发明的较佳实施例，并不用以限制本发明，凡在本发明的精神和原则之内，所作的任何修改、等同替换、改进等，均应包含在本发明的保护范围之内。 The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., which are within the spirit and scope of the present invention, should be included in the protection of the present invention. Within the scope.

Claims

权利要求 Rights request

1、一种频偏纠正方法，其特征在于，包括： A frequency offset correction method, comprising:

根据所述频偏估计结果对所述用户在当前分组数据中的频域数据进行频偏纠正。 And performing frequency offset correction on the frequency domain data of the user in the current packet data according to the frequency offset estimation result.

2、如权利要求 1所述的频偏纠正方法，其特征在于，当没有已经过频偏的分组数据中的频偏糾正结果时，设置所述用户在当前分组数据中的频偏估计结果为零。 2. The frequency offset correction method according to claim 1, wherein when the frequency offset correction result in the packet data that has been frequency offset is not present, setting a frequency offset estimation result of the user in the current packet data is zero.

3、如权利要求 1所述的频偏纠正方法，其特征在于，所述根据所述用户在当前分组数据中的导频数据以及所述用户在已经过频偏纠正的分组数据中的频偏纠正结果，获得所述用户在当前分组数据中的频偏估计结果，包括： 3. The frequency offset correction method according to claim 1, wherein the pilot data according to the user in current packet data and the frequency offset of the user in packet data that has been subjected to frequency offset correction Correcting the result, obtaining the frequency offset estimation result of the user in the current packet data, including:

根据所述用户在当前分组数据中的导频数据获得所述用户在当前分组数据中的频偏估计值； Obtaining a frequency offset estimation value of the user in current packet data according to pilot data of the user in current packet data;

根据所述用户在当前分组数据中的频偏估计值，获得所述用户在当前分组数据中的候选频偏估计结果； Obtaining a candidate frequency offset estimation result of the user in the current packet data according to the frequency offset estimation value of the user in the current packet data;

才艮据所述用户在已经过频偏纠正的分组数据中的频偏纠正结果，在所述候选频偏估计结果中选择所述用户在当前分组数据中的频偏估计结果。 And selecting a frequency offset estimation result of the user in the current packet data in the candidate frequency offset estimation result according to the frequency offset correction result of the user in the packet data that has been subjected to the frequency offset correction.

4、如权利要求 3所述的频偏纠正方法，其特征在于，所述根据所述用户在当前分组数据中的导频数据获得所述用户在当前分组数据中的频偏估计值，包括： The frequency offset correction method according to claim 3, wherein the obtaining the frequency offset estimation value of the user in the current packet data according to the pilot data of the user in the current packet data comprises:

获取所述导频数据的信道冲击响应系数估计值； Obtaining an estimated channel impulse response coefficient of the pilot data;

根据相邻最近的两个导频信号的信道冲击响应系数估计值获取所述用户的当前分组的频偏估计值。 Obtaining the user's based on channel impulse response coefficient estimates of two nearest neighbor pilot signals The estimated frequency offset of the current packet.

5、如权利要求 3所述的频偏纠正方法，其特征在于，所述根据所述用户在当前分组数据中的频偏估计值，获得所述用户在当前分组数据中的候选频偏估计结果，包括： The frequency offset correction method according to claim 3, wherein the obtaining a candidate frequency offset estimation result of the user in current packet data according to the frequency offset estimation value of the user in current packet data , including:

将所述用户的实际频偏范围划分为多个频偏区间，才据所述用户在当前分组数据中的频偏估计值在其所属频偏区间内的位置，将在所述多个频偏区间的其余频偏区间内获得的相同位置处对应的频偏估计值作为候选频偏估计结果。 Dividing the actual frequency offset range of the user into a plurality of frequency offset intervals, according to the location of the frequency offset estimation value of the user in the current packet data in the frequency offset interval to which the user belongs, The corresponding frequency offset estimation value at the same position obtained in the remaining frequency offset interval of the interval is used as the candidate frequency offset estimation result.

6、如权利要求 5所述的频偏纠正方法，其特征在于，所述用户在已经过频偏纠正的分组数据中的频偏纠正结果为：所述用户在已经过频偏纠正的分组数据中进行频偏纠正后的循环冗余码校验 CRC反馈；候选频偏估计结果中选择当前分组的频偏估计结果，包括： 6. The frequency offset correction method according to claim 5, wherein the frequency offset correction result of the user in the packet data that has undergone frequency offset correction is: the packet data of the user that has been subjected to frequency offset correction. The cyclic redundancy code check CRC feedback after frequency offset correction is performed; the frequency offset estimation result of the current packet is selected in the candidate frequency offset estimation result, including:

如果所述用户在已经过频偏纠正的分组数据的频偏纠正后的 CRC反馈为错误，选择所述用户在当前分组数据中的候选频偏估计结果中与所述用户在已经过频偏纠正的分组数据的频偏估计结果属于不同频偏区间的候选频偏估计结果作为当前分组的频偏估计结果；确，选择所述用户在当前分组数据中的候选频偏估计结果中与所述用户在已经过频偏纠正的分组数据的频偏估计结果属于相同频偏区间的候选频偏估计结果作为当前分组的频偏估计结果。 If the CRC feedback of the user after the frequency offset correction of the packet data that has been subjected to the frequency offset correction is an error, the user is selected to have a frequency offset correction with the user in the candidate frequency offset estimation result in the current packet data. The frequency offset estimation result of the packet data belongs to the candidate frequency offset estimation result of the different frequency offset interval as the frequency offset estimation result of the current packet; indeed, selecting the candidate frequency offset estimation result of the user in the current packet data and the user The frequency offset estimation result of the packet data that has undergone the frequency offset correction belongs to the candidate frequency offset estimation result of the same frequency offset section as the frequency offset estimation result of the current packet.

7、如权利要求 5所述的频偏纠正方法，其特征在于，所述方法还包括：将每个频偏区间划分为边界子区间和非边界子区间； The frequency offset correction method according to claim 5, wherein the method further comprises: dividing each frequency offset interval into a boundary sub-interval and a non-boundary sub-interval;

则当所述频偏估计值在其所属的频偏区间内从一个边界子区间改变至另一个边界子区间时，使用与改变前的边界子区间相邻的频偏区间中的频偏估计值作为当前分组的频偏值。 Then, when the frequency offset estimation value changes from one boundary subinterval to another boundary subinterval within the frequency offset interval to which it belongs, the frequency offset estimation value in the frequency offset interval adjacent to the boundary subinterval before the change is used. As the frequency offset value of the current packet.

8、一种网络侧设备，其特征在于，所述设备包括： A network side device, wherein the device includes:

接收模块，用于接收当前分组数据，根据所述接收到的当前分组数据获取用户在当前分组数据中的频域数据和导频数据； a receiving module, configured to receive current packet data, and obtain the current packet data according to the received Frequency domain data and pilot data of the user in the current packet data;

获得模块，用于根据所述用户在当前分组数据中的导频数据以及所述用户在已经过频偏糾正的分组数据中的频偏纠正结果，获得所述用户在当前分组数据中的频偏估计结果； And an obtaining module, configured to obtain, according to the pilot data of the user in the current packet data and the frequency offset correction result of the user in the packet data that has been subjected to the frequency offset correction, obtaining the frequency offset of the user in the current packet data Estimated result;

频偏纠正模块，用于根据所述获得模块获得的频偏估计结果对所述用户在当前分组数据中的频域数据进行频偏纠正。 And a frequency offset correction module, configured to perform frequency offset correction on the frequency domain data of the user in the current packet data according to the frequency offset estimation result obtained by the obtaining module.

9、如权利要求 8所述的网络侧设备，其特征在于，当没有已经过频偏的分组数据中的频偏纠正结果时，所述获得模块还用于：设置所述用户在当前分组数据中频偏估计结果为零。 The network side device according to claim 8, wherein the obtaining module is further configured to: set the current packet data of the user when there is no frequency offset correction result in the packet data that has been frequency offset The IF bias estimation result is zero.

10、如权利要求 8所述的网络侧设备，其特征在于，所述获得模块包括：频偏估计值获得单元，用于根据所述用户在当前分组数据中的导频数据获得所述用户在当前分组数据中的频偏估计值； The network side device according to claim 8, wherein the obtaining module comprises: a frequency offset estimation value obtaining unit, configured to obtain, according to pilot data of the user in current packet data, the user The frequency offset estimate in the current packet data;

候选频偏估计结果获得单元 , 用于根据所述用户在当前分组数据中的频偏估计值，获得所述用户在当前分组数据中的候选频偏估计结果； a candidate frequency offset estimation result obtaining unit, configured to obtain, according to the frequency offset estimation value of the user in the current packet data, a candidate frequency offset estimation result of the user in current packet data;

频偏估计结果获得单元，用于才 M居所述用户在已经过频偏纠正的分组数据中的频偏糾正结果，在所述候选频偏估计结果中选择所述用户在当前分组数据中的频偏估计结果。 a frequency offset estimation result obtaining unit, configured to perform a frequency offset correction result of the user in the packet data that has undergone frequency offset correction, and select, in the candidate frequency offset estimation result, the user in the current packet data Frequency offset estimation results.

11、如权利要求 10所述的网络侧设备，其特征在于，所述频偏估计值获得单元包括： The network side device according to claim 10, wherein the frequency offset estimation value obtaining unit comprises:

系数估计子单元，用于获取所述导频数据的信道冲击响应系数估计值；获得子单元，用于根据所述系数估计子单元中获得的相邻最近的两个导频信号的信道冲击响应系数估计值获取所述用户的当前分组的频偏估计值。 a coefficient estimation subunit, configured to obtain a channel impulse response coefficient estimation value of the pilot data; and a obtaining subunit, configured to estimate a channel impulse response of the neighboring two nearest pilot signals obtained in the subunit according to the coefficient The coefficient estimate obtains a frequency offset estimate for the current packet of the user.

12、如权利要求 10所述的网络侧设备，其特征在于，所述候选频偏估计结果单元包括： The network side device according to claim 10, wherein the candidate frequency offset estimation result unit comprises:

频偏区间划分子单元，用于将所述用户的实际频偏范围划分为多个频偏区间；获得子单元，用于# ^居所述用户在当前分组数据中的频偏估计值在其所属频偏区间内的位置，将在所述多个频偏区间的其余频偏区间内获得的相同位置处对应的频偏估计值作为候选频偏估计结果。 a frequency offset interval dividing sub-unit, configured to divide the actual frequency offset range of the user into multiple frequency offset intervals; Obtaining a subunit, where the location of the frequency offset estimation value of the user in the current packet data is within the frequency offset interval to which the user belongs, and the same is obtained in the remaining frequency offset intervals of the plurality of frequency offset intervals The corresponding frequency offset estimation value at the position is used as the candidate frequency offset estimation result.

13、如权利要求 10所述的网络侧设备，其特征在于，所述用户在已经过频偏纠正的分组数据中的频偏纠正结果为：所述用户在已经过频偏纠正的分组数据中进行频偏糾正后的循环冗余码校验 CRC反馈； The network side device according to claim 10, wherein the frequency offset correction result of the user in the packet data that has been subjected to the frequency offset correction is: the user is in the packet data that has been subjected to the frequency offset correction. Performing cyclic redundancy check CRC feedback after frequency offset correction;

则所述频偏估计结果获得单元用于：误，选择所述用户在当前分组数据中的候选频偏估计结果中与所述用户在已经过频偏纠正的分组数据的频偏估计结果属于不同频偏区间的候选频偏估计结果作为当前分组的频偏估计结果；确，选择所述用户在当前分组数据中的候选频偏估计结果中与所述用户在已经过频偏纠正的分组数据的频偏估计结果属于相同频偏区间的候选频偏估计结果作为当前分组的频偏估计结果。 And the frequency offset estimation result obtaining unit is configured to: select, select, in the candidate frequency offset estimation result in the current packet data, that the user is different from the frequency offset estimation result of the packet data that has been frequency offset corrected by the user. The candidate frequency offset estimation result of the frequency offset interval is used as the frequency offset estimation result of the current packet; indeed, selecting the candidate frequency offset estimation result of the user in the current packet data and the packet data of the user that has been frequency offset corrected The frequency offset estimation result belongs to the candidate frequency offset estimation result of the same frequency offset interval as the frequency offset estimation result of the current packet.

14、如权利要求 12所述的网络侧设备，其特征在于，所述候选频偏估计结果单元还包括： The network side device according to claim 12, wherein the candidate frequency offset estimation result unit further comprises:

子区间划分子单元，将每个频偏区间划分为边界子区间和非边界子区间；则所述获得子单元还用于： The sub-interval divides the sub-units, and divides each frequency offset interval into a boundary sub-interval and a non-boundary sub-interval; then the obtained sub-unit is further used to:

当所述频偏估计值在其所属的频偏区间内从一个边界子区间改变至另一个边界子区间时，使用与改变前的边界子区间相邻的频偏区间中的频偏估计值作为当前分组的频偏值。 When the frequency offset estimation value is changed from one boundary subinterval to another boundary subinterval within the frequency offset interval to which it belongs, the frequency offset estimation value in the frequency offset interval adjacent to the boundary subinterval before the change is used as The frequency offset value of the current packet.

15、如权利要求 8-14任一项所述的网络侧设备，其特征在于，所述网络侧设备为基站。 The network side device according to any one of claims 8 to 14, wherein the network side device is a base station.