CN101547062B - Method and device for correcting frequency deviation - Google Patents
Method and device for correcting frequency deviation Download PDFInfo
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Abstract
本发明实施例公开了一种频偏纠正方法和设备,属于通信领域。所述方法包括: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;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;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。所述设备包括:接收模块、获得模块和频偏纠正模块。通过采用用户在已经过频偏纠正的分组数据中的频偏纠正结果反馈,来获得用户在当前分组数据中的频偏纠正结果,大大减少了AFC的复杂度。
The embodiment of the invention discloses a frequency offset correction method and equipment, belonging to the communication field. The method includes: receiving current packet data, obtaining frequency domain data and pilot data of the user in the current packet data according to the received current packet data; The frequency offset correction result of the user in the packet data that has undergone frequency offset correction is obtained to obtain the frequency offset estimation result of the user in the current packet data; and the frequency offset estimation result of the user in the current packet data is obtained according to the frequency offset estimation result frequency domain data for frequency offset correction. The device includes: a receiving module, an obtaining module and a frequency offset correcting module. The frequency offset correction result of the user in the current packet data is obtained by using the frequency offset correction result feedback of the user in the packet data that has undergone frequency offset correction, which greatly reduces the complexity of the AFC.
Description
技术领域 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。The invention relates to the communication field, in particular to a frequency offset correction method and equipment.
背景技术 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 3GPP (3rd Generation Partnership Project, 3rd Generation Partnership Project), LTE (Long Term Evolution, long-term evolution) project is the largest new technology research and development project launched by 3GPP in the past two years. This kind of OFDM (Orthogonal Frequency Division Multiple Access , Orthogonal Frequency Division Multiple Access)/FDMA (Frequency Division Multiple Access, Frequency Division Multiple Access) as the core 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,这样可以减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,最大限度地提高系统性能。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系统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, multi-carrier modulation). The main idea is: divide the channel into several orthogonal sub-channels, convert high-speed data signals into parallel low-speed sub-data streams, and modulate them on each sub-channel for transmission. Orthogonal signals can be separated by using correlation techniques at the receiving end, which can reduce the mutual interference between sub-channels. The signal bandwidth on each sub-channel is smaller than the correlation bandwidth of the channel, so each sub-channel can be regarded as flat fading, so that inter-symbol interference can be eliminated. And since the bandwidth of each sub-channel is only a small part 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 will cause phase rotation of time-domain samples, causing phase deviation between different OFDM symbols, and destroying the orthogonality between subcarriers of OFDM system. Thereby deteriorating the demodulation performance. Therefore, an estimation of the frequency offset is required.
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(FastFourier 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。The AFC (Automatic Frequency Correction, automatic frequency offset correction) method in the prior art uses a method of CP (Cyclic Prefix, cyclic prefix) frequency offset estimation combined with a pilot reference signal frequency offset estimation method to estimate the frequency offset. Among them, the CP in the time domain separates the user's frequency domain signal through DFT (Discrete Fourier Transform, Discrete Fourier Transform), and the phase between the frequency domain data of the FFT (FastFourier Transform, Fast Fourier Transform) symbol part of the user's OFDM symbol The corresponding frequency offset can be calculated by the difference. Since the CP is a partial repetition of the data FFT symbol, and the time interval between the CP part and the data repetition part is not large, a larger frequency offset range can be covered by using this repetition characteristic.
在实现本发明的过程中,发明人发现上述现有技术至少具有以下缺点:In the process of realizing the present invention, the inventors have found that the above-mentioned prior art has at least the following disadvantages:
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;It is necessary to save the CP signal in the time domain, and additionally perform DFT processing on the CP, which has high complexity;
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。Moreover, the CP in the time domain is more affected, and the timing deviation will shorten the effective length of the CP. The CP contains signals of multiple users, especially the CP is not a complete FFT symbol, so the CP signal is transformed into the frequency domain of different users. Signal interference occurs. Therefore, the accuracy of estimating the frequency offset using the CP is poor, and even if it is estimated in combination with the pilot reference signal, the error probability is still relatively high.
发明内容 Contents of the invention
为了降低频偏纠正的复杂度,并保证系统可靠、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。所述技术方案如下:In order to reduce the complexity of frequency offset correction and ensure reliable and safe operation of the system, embodiments of the present invention provide a frequency correction method and device. Described technical scheme is as follows:
一种频偏纠正方法,包括:A frequency offset correction method, comprising:
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 the current packet data, and obtaining 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;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 undergone 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;performing frequency offset correction on frequency domain data of the user in the current packet data according to the frequency offset estimation result;
其中,所述获得所述用户在当前分组数据中的频偏估计结果,具体包括:Wherein, the obtaining the frequency offset estimation result of the user in the current packet data specifically includes:
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 an estimated frequency offset value of the user in the current packet data according to the pilot data of the user in the 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;
根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。According to the frequency offset correction result of the user in the packet data that has undergone frequency offset correction, the frequency offset estimation result of the user in the current packet data is selected from the candidate frequency offset estimation results.
一种网络侧设备,包括:A network side device, comprising:
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;An obtaining module, configured to obtain the frequency offset 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 undergone frequency offset correction estimated results;
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;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;
其中,所述获得模块,具体包括:Wherein, the obtaining module specifically includes:
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;a frequency offset estimation value obtaining unit, configured to obtain an estimated frequency offset value of the user in the current packet data according to the pilot data of the user 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 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,用于根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。A frequency offset estimation result obtaining unit, configured to select the frequency offset of the user in the current packet data from the candidate frequency offset estimation results according to the frequency offset correction result of the user in the packet data that has undergone frequency offset correction Estimated results.
本发明实施例提供的技术方案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结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。本发明实施例的提供的技术方案运算复杂度较小,能够保证系统可靠、有效的工作。In the technical solution provided by the embodiment of the present invention, a more accurate frequency offset estimation result is obtained by combining the frequency offset correction result of the user in the packet data that has undergone frequency offset correction and the pilot data of the user in the current packet data, and according to the obtained The frequency offset correction result performs frequency offset correction on the user's frequency domain data in the current packet data. The technical solutions provided by the embodiments of the present invention have less computational complexity and can ensure reliable and effective work of the system.
附图说明 Description of drawings
图1是本发明实施例一提供的频率纠正方法流程图;FIG. 1 is a flowchart of a frequency correction method provided by 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;FIG. 2 is a schematic diagram of a signal received by a receiving end provided in Embodiment 1 of the present invention;
图3是本发明实施例二提供的频率纠正方法流程图;FIG. 3 is a flowchart of a frequency correction method provided by 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;FIG. 4 is a schematic diagram of division of frequency offset intervals provided by 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;FIG. 5 is a schematic diagram of sub-interval division of the frequency offset interval provided by 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;FIG. 6 is a schematic structural diagram of a network-side device provided in 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;FIG. 7 is a schematic structural diagram of an acquisition module provided by 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。Fig. 8 is a schematic structural diagram of a candidate frequency offset estimation result unit provided by Embodiment 3 of the present invention.
具体实施方式 Detailed ways
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。In order to make the object, technical solution and advantages of the present invention clearer, the implementation manner of the present invention will be further described in detail below in conjunction with the accompanying drawings.
实施例一Embodiment one
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:Referring to Fig. 1, an embodiment of the present invention provides a frequency offset correction method, which mainly includes:
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;101: Receive the current packet data, and acquire frequency domain data and pilot data of the user in the current packet data according to the received current packet 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 group may consist of several OFDM symbols, pilot data is allocated in a few OFDM symbols, and the nearest two OFDM symbols containing pilot data are separated 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;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 user in the packet data that has undergone frequency offset correction;
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纠正。The packet data that has undergone frequency offset correction may include: any group of packet data received before receiving the current packet data, each user in the packet data is respectively Frequency offset correction.
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 CRC (Cyclic Redundancy Check, Cyclic Redundancy Check) feedback, or other results that can identify whether the frequency offset corrected data is correct or not.
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纠正。103: Correct the frequency offset of the user's frequency domain data in the current packet data according to the frequency offset estimation result.
本发明实施例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结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。本发明实施例的技术方案运算复杂度较小,能够保证系统可靠、有效的工作。In the embodiment of the present invention, a relatively accurate frequency offset estimation result is obtained by combining the frequency offset correction result of the user in the packet data that has undergone frequency offset correction with the user's pilot data in the current packet data, and according to the obtained frequency offset correction result Frequency offset correction is performed on the frequency domain data of the user in the current packet data. The technical solutions of the embodiments of the present invention have less computational complexity and can ensure reliable and effective work of the system.
实施例二Embodiment two
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:The embodiment of the present invention provides a frequency offset correction method, taking the mobile terminal as the sending end and the base station as the receiving end as an example, see Figure 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 sent by the mobile terminal through 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。What needs to be explained here is that the base station receives the high-speed serial data stream modulated on a single carrier by the mobile terminal, divides it into multiple low-speed data streams, and modulates the time-domain data sent in parallel on multiple orthogonal sub-carriers.
基站接收到的每个子载波发送的时域数据是以分组为单位进行发送的。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;The time-domain data sent by each subcarrier received by the base station is sent in units of packets. Each group can be composed of several OFDM symbols, pilot data is allocated in a small number of OFDM symbols, and the nearest two OFDM symbols containing pilot data are separated by P OFDM symbols;
其中,一个OFDM符号由CP和FFT样点组成。CP的长度为Ncp,FFT样点的数量为NFFT,一个OFDM符号的长度=Ncp+NFFT。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纠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。Wherein, one OFDM symbol is composed of CP and FFT samples. The length of the CP is N cp , the number of FFT samples is N FFT , and the length of one OFDM symbol=N cp +N FFT . The advantage of sending time-domain data in units of packets is that the amount of data in each group is relatively small. Compared with continuously sending all OFDM symbols, when the base station performs frequency offset correction in units of a group, the amount of processed data will decrease. At the same time, the base station performs frequency offset correction in units of one group, and the frequency offset correction result of each group can prompt and help the frequency offset correction of the next group, reducing the need for continuous correction of all OFDM Timing errors caused by symbols.
302:获取每个用户在当前分组数据中的频域数据和导频数据;302: Obtain frequency domain data and pilot data of each user in the 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 group and discards it, performs FFT transformation and user separation on the FFT samples, and obtains each A user's frequency domain data and pilot data in the 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 taking out and discarding the CP in the time-domain data of the current packet received can greatly reduce the computational complexity of the entire frequency offset estimation process; using FFT samples for FFT transform user separation can properly reduce multi-user interference between them.
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。This embodiment takes the frequency domain data and pilot data of the mth user in the current group as an example.
其中,将基站接收到的频域上第k个子载波中的第r个OFDM符号中的频域数据表示为R(k,r);Wherein, the frequency domain data in the rth OFDM symbol in the kth subcarrier on the frequency domain received by the base station is represented as R(k, r);
如果频域上第k个子载波中的第n个OFDM符号中包括导频数据,则该导频数据可以表示为RRS(k,n),其中k=0,1,......K-1,其中K是导频数据的总数。If the n-th OFDM symbol in the k-th subcarrier in the frequency domain includes pilot data, the pilot data can be expressed as R RS (k, n), where k=0, 1, … K-1, where K is the total number of pilot 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: Estimate the channel impulse response coefficient on the pilot data of the current group of the mth user, and obtain the estimated value of the 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。The embodiment of the present invention takes the LS (Least Square, least squares) method to obtain the estimated value of the channel impulse response coefficient as an example. In addition, methods such as maximum likelihood estimation and DFT transform domain channel estimation can also be used to obtain the channel impulse response coefficient. , the process is basically the same as that of LS estimation, and will not be repeated here.
第k个子载波中的第n个OFDM符号中导频数据的信道冲击响应系数的估计值HLS(k,n)可以表示为:The estimated value H LS (k, n) of the channel impulse response coefficient of the pilot data in the nth OFDM symbol in the kth subcarrier can be expressed as:
其中,SRS(k,n)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,SRS(k,n)是双方都已知的。S* RS(k,n)表示SRS(k,n)的共轭。Wherein, S RS (k, n) refers to the pilot reference signal sent by the mobile terminal without channel impact. For the base station and the mobile terminal, S RS (k, n) is known to both parties. S * RS (k,n) represents the conjugate of SRS (k,n).
由于移动终端发送的导频参考信号一般有|SRS(k,n)|2=1,所以上式可以简化为:Since the pilot reference signal sent by the mobile terminal generally has |S RS (k, n)| 2 =1, the above formula can be simplified as:
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: Acquire the estimated frequency offset value of the current group of the mth user according to the estimated values of the channel impulse response coefficients of the two closest adjacent pilot data in the current group;
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HLS(k,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HLS(k,n+P-1)。它们之间的相位差值为:Specifically, since there is a difference of (P-1) OFMD symbols between the serial number of the OFDM symbol where the previous pilot data is located and the serial number of the OFDM symbol where this pilot data is located, when the channel impact of the previous pilot data When the LS estimation result of the response coefficient is H LS (k, n), the LS estimation result of the channel impulse response coefficient of the nearest adjacent pilot data is H LS (k, n+P-1). The phase difference between them is:
这里需要说明的是,设
其次,根据相位差值θ,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,在此不做详述。Secondly, according to the phase difference θ, calculate the estimated value of the fractional frequency offset of the actual frequency offset value of the mth user's current group. The method of the bias estimation value is basically similar to the method of the fractional frequency offset estimation value, and will not be described in detail here.
具体地,小数频偏估计值可以根据下式进行计算:Specifically, the fractional frequency offset estimation value can be calculated according to the following formula:
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。What needs to be explained here is that due to the fact that within a group, the nearest two adjacent pilot data are separated by P-1 OFDM symbols, and the interval is relatively large, the frequency offset range of the pilot frequency estimation is small, which is not enough to cover the actual Frequency offset range. Therefore, the actual frequency offset value of the current group of the mth user needs to be further processed through the estimated frequency offset value obtained by the pilot estimation.
305:根据导频估计的第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: Obtain a candidate frequency offset estimation result of the current group of the m-th user within the actual frequency offset range according to the estimated frequency offset value of the current group of the m-th user estimated by the pilot;
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 frequency 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 in 304 is used among them The position in the frequency offset interval to which it belongs, obtains the candidate frequency offset estimation result of the current group of the m-th user in the same position as the fractional frequency offset estimation value in the frequency offset interval.
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)基站根据上行系统的载波频率F和移动终端相对于基站的移动速度V计算该上行系统可能达到的实际频偏范围,其中,频偏正比于系统载波频率F和移动终端相对于基站的移动速度V。1) The base station calculates the 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 carrier frequency F of the system and the movement of the mobile terminal 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,该上行系统可能达到实际的最大频偏范围可以表示为 Specifically, the maximum frequency offset range that the actual frequency offset can achieve is Among them, C represents the speed of light; then, the actual maximum frequency deviation range that the uplink system may reach 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 frequency estimation;
由于该上行系统为已知,那么移动终端和基站之间导频估计的频偏范围即为已知。设导频估计的频偏范围为那么其中NRS是两个包含导频数据的OFMD符号之间相隔的时域样点个数,Δf是子载波之间的频率间隔。Since the uplink system is known, the frequency offset range of the pilot estimation between the mobile terminal and the base station is known. Let the frequency offset range of pilot frequency estimation be So Where N RS is the number of time-domain samples separated between two OFMD symbols containing pilot data, and Δf is the frequency spacing between subcarriers.
相应的,导频估计的频偏估计范围为 Correspondingly, the frequency offset estimation range of the pilot frequency estimation is
3)利用导频估计的频偏估计范围将该上行系统可能达到的实际频偏范围εmax划分为多个频偏区间;3) Using the frequency offset estimation range of pilot frequency estimation The actual frequency offset range ε max that the uplink system may achieve 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εzone,将εmax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 ε zone , ε max is divided into U frequency offset intervals, starting from the position where the frequency offset is zero as the center point of the first frequency offset interval, and proceeding to the two directions of negative frequency offset and positive frequency offset respectively Division of frequency offset intervals. The divided frequency offset intervals are marked with 1, 2, . . . , U respectively. Wherein, due to the division method of the frequency offset interval, all the frequency offset intervals are symmetrical with respect to the first frequency offset interval, so the value of U is an odd number. The value of U can be changed by setting The value of is rounded up for calculation. When the calculated value of U is an even number, the actual value of U needs to be added by 1.
例如,假设U为3,那么区间的划分可以如图4所示,第一个频偏区间的范围是第二个频偏区间位于第一个频偏区间的负向,范围是第三个频偏区间位于第一个频偏区间的正向,范围是
例如,假设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]。假设导频估计的第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,根据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。For example, assuming that the actual frequency offset range of the user is [-10, 10], and the frequency offset estimation range of the pilot estimation is [-3, 3], the actual frequency offset range of the user is calculated by using the frequency offset estimation range of the pilot estimation For division of frequency offset intervals, the divided frequency offset intervals may be expressed as [-10, -9], [-9, -3], [-3, 3], [3, 9], [9, 10]. Assume that the fractional frequency offset value of the current group of the mth user estimated by the pilot is 1, which falls within the frequency offset interval of [-3, 3]. According to the position of 1 in the current frequency offset interval, the frequency offset interval The left endpoint is 4 larger and 2 smaller than the right endpoint of the frequency offset interval, and the estimated frequency offset value of the current group of the mth user within the actual frequency offset range is obtained in the entire frequency offset interval, namely: [-10, -9], [9, 10] There is no such frequency offset estimate in the two frequency offset intervals, the frequency offset estimate in the [-9, -3] frequency offset interval is -5, [3, 9] in the frequency offset interval The frequency offset estimate 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;306: According to the frequency offset correction result of the packet data that has undergone frequency offset correction, select the candidate frequency offset estimation result of which frequency offset interval to use as the frequency offset estimation result;
其中,已经过频偏纠正的分组数据的频偏纠正结果可以为CRC反馈,CRC反馈具体是指:已经过频偏纠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。Wherein, the frequency offset correction result of the packet data that has undergone frequency offset correction can be CRC feedback, and CRC feedback specifically refers to: the frequency offset correction result of the packet data that has undergone frequency offset correction is subjected to CRC after demodulation and decoding 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组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纠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 frequency offset correction is an error, it means that the frequency offset estimation result used by the packet data that has undergone frequency offset correction is not the actual frequency offset value of the mth user, and has The frequency offset interval of the frequency offset estimation result used by the offset-corrected packet data is not the frequency offset interval of the mth user's actual frequency offset value, so the frequency offset estimation used by the packet data that has been frequency offset corrected is used As a result, the candidate frequency offset estimation results of different frequency offset intervals are used as the frequency offset estimation results of the current packet data, and continue to perform frequency offset estimation on the packet data; There may be multiple frequency offset intervals with different frequency offset intervals 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纠正结果的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,使用与已经过频偏纠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 frequency offset corrected packet data is correct, it means that the frequency offset estimation result adopted by the frequency offset corrected packet data is the actual frequency offset value of the mth user, correspondingly, The frequency offset interval where the frequency offset estimation result is located is also the frequency offset interval to which the actual frequency offset value belongs, so continue to use the frequency offset interval where the frequency offset estimation result of the packet data that has undergone frequency offset correction belongs, and use the frequency offset interval that has been corrected. Candidate frequency offset estimation results in the same frequency offset interval as the frequency offset estimation results adopted by the packet data are used as the frequency offset estimation results 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 request the mobile terminal to retransmit the original packet data, so as to correct the frequency offset of all the 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纠正的分组数据的频偏纠正结果的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 group of packet data, since there is no CRC feedback of the frequency offset correction result of the packet data that has undergone frequency offset correction, the frequency offset value can be set to an optimal Possible values, or initialized to zero, i.e. assuming no frequency offset.
307:根据第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:将进行频偏纠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 frequency offset corrected data, and use the demodulated and decoded data as the frequency offset correction result to provide reference for other packet data to select the frequency offset estimation result from the 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, performing CRC on the demodulated and decoded data 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 correctness of the actual frequency offset value is not affected when the estimated frequency offset value jumps, each frequency offset interval can 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 subinterval and a non-boundary subinterval.
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 may also be divided into multiple non-boundary sub-intervals, and the frequency range of each sub-interval is not smaller than the jitter range of the frequency offset. Here, the jitter range refers to the minimum value of frequency offset variation.
参见图5,假设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 , assuming U=3, each frequency offset interval can be divided into three subintervals A, B, and C, wherein subinterval A belongs to the non-boundary subinterval, and subintervals B and C belong to the boundary subinterval.
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 there are no strict regulations on the division of subintervals. The interval can be divided into thirds, or the proportion of non-boundary subintervals in the entire interval can be higher than that of boundary subintervals. Of course, the non-boundary subintervals can also be further divided, that is, the frequency offset interval can be divided into 4, 5 ... subintervals, including 2 boundary subintervals and multiple non-boundary subintervals.
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;B) Judging the estimated value of decimal frequency offset Which sub-interval falls in the divided frequency offset interval;
如图5所示,假设估计出来的位于第一频偏区间的A1子区间的X1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。As shown in Figure 5, assume that the estimated The X1 position in the A1 subinterval of the first frequency offset interval, correspondingly, the X2 position in the A2 subinterval of the second frequency offset interval, and the X3 position in the A3 subinterval of the third frequency offset interval are both the mth user The candidate frequency offset estimation results of the current group.
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B1、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 is initially in the subinterval A2 in frequency offset interval 2. After several groups, the actual frequency offset value may have changed to a certain position of C2, since C2 still belongs to the frequency range 2, so this 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 estimated value can be one of B1, B2, and B3, but if at this time Locking still considers that the actual frequency offset value is in the frequency offset interval 2, so there is a deviation from the actual frequency offset value, so it is necessary to track the frequency offset interval, which can provide a reference value for future frequency offset estimation. The specific method is 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) Track the actual frequency offset value of each group. When the actual frequency offset value changes from one boundary subinterval to another boundary subinterval, the frequency offset interval needs to be changed to a frequency offset adjacent to the boundary subinterval before the change Interval, so as to complete the interval change and effectively prevent the jitter in 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 the CRC has continuous errors after the frequency offset interval is determined, it is necessary to re-search the frequency offset interval until the CRC feedback is correct.
具体的,假设从A1子区间开始,第1个分组采用(A1)作为频偏估计结果,其中(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(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纠正,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, assuming that starting from the A1 subinterval, the first group uses (A1) As the frequency offset estimation result, where (A1) is the estimated frequency offset value of the A1 sub-interval. After demodulation and decoding, the CRC feedback is obtained. If the received CRC feedback is wrong, the second group can use (A2) as the frequency offset estimation result of the A2 sub-interval, and so on until the received CRC feedback is correct. Of course, only one group can be used for automatic frequency offset correction, that is, according to a certain order, use the candidate frequency offset estimation results in different frequency offset intervals to perform frequency offset correction on the frequency domain data of the mth user in the same group , 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以外的系统,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纠正。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的基础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 systems other than OFDM. As long as the frequency offset estimation range of the reference signal is small and the actual frequency offset is large, the frequency offset can be corrected by this method. . It only needs to use the frequency offset period estimated by the reference signal as the interval, divide the actual frequency offset into several intervals, and then perform interval search and interval tracking on the basis of feedback CRC, so as to lock the frequency offset interval and obtain 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组数据中进行有效频偏纠正的效果。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,能够保证系统可靠、有效的工作。In the embodiment of the present invention, the actual frequency offset range that the user may reach is divided into several frequency offset intervals, and the frequency offset estimation is performed in combination with the user's pilot data in the current packet data, and the frequency offset is corrected by the user in the packet data that has been corrected. The frequency offset correction result of the user can be obtained to obtain a relatively accurate frequency offset estimation result of the user in the current group, so as to achieve the effect of effectively correcting the frequency offset of the user in the current group data. Moreover, the reliability and stability of frequency tracking are guaranteed through effective interval division technology, and interval jitter will not occur. The technical solutions of the embodiments of the present invention have less computational complexity, are less affected by timing errors and multi-user interference, and can ensure reliable and effective work of the system.
实施例三Embodiment three
参见图6,本发明实施例提供了一种网络侧设备,包括:Referring to Figure 6, an embodiment of the present invention provides a network side device, including:
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;The receiving
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,获得用户在当前分组数据中的频偏估计结果;An obtaining
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纠正。The frequency offset
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 here that when no frequency offset correction is performed on all packet data, the obtaining
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:Wherein, referring to the corresponding description of the previous method embodiment, referring to FIG. 7, the obtaining
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;A frequency offset estimation
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
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
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 descriptions of the foregoing method embodiments, the frequency offset estimation
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;The coefficient estimation subunit is used to obtain the estimated value of the channel impulse response coefficient of the pilot data;
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。The obtaining subunit is configured to obtain the estimated frequency offset value of the user's current group according to the estimated values of the channel impulse response coefficients of the two closest adjacent pilot signals obtained in the coefficient estimation subunit.
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 previous method embodiment, referring to FIG. 8, the candidate frequency offset
频偏区间划分子单元602B1,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 division subunit 602B1 is used to divide the predicted actual frequency offset range of the 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 subunit 602B2 is configured to obtain a plurality of candidate frequency offset estimation results with the same position in multiple 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 it 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:Wherein, referring to the corresponding description of the foregoing method embodiments, the frequency offset interval division subunit 602B1 is used to:
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。The frequency offset estimation range of the pilot frequency estimation is taken as the size of a frequency offset interval, and the position where the frequency offset is zero is taken as the midpoint of the first frequency offset interval, and the frequency offset is positive and the frequency offset is negative respectively. The predicted actual frequency offset range of the user is divided into multiple 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: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反馈时,频偏估计结果获得单元602C用于:It should be noted that when the frequency offset correction result of the user in the packet data that has undergone frequency offset correction is: when the user performs the CRC feedback after frequency offset correction in the packet data that has undergone frequency offset correction , the frequency offset estimation
如果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;If the user's CRC feedback after frequency offset correction of the packet data that has undergone frequency offset correction is an error, select the frequency offset between the user's candidate frequency offset estimation results in the current packet data and the user's frequency offset corrected packet data The candidate frequency offset estimation results whose estimation results belong to different frequency offset intervals are used as the frequency offset estimation results of the current group;
如果用户在已经过频偏纠正的分组数据的频偏纠正后的CRC反馈为正确,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 user's CRC feedback after frequency offset correction of the packet data that has undergone frequency offset correction is correct, select the frequency offset between the user's candidate frequency offset estimation results in the current packet data and the user's frequency offset corrected packet data The candidate frequency offset estimation results whose estimation results belong to the same frequency offset interval are used as the frequency offset estimation results of the current group.
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 embodiments, the candidate frequency offset
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;The sub-interval is divided into sub-units, and each frequency offset interval is divided into a boundary sub-interval and a non-boundary sub-interval;
则获得子单元602B2还用可以于:Then the obtaining subunit 602B2 can also be used for:
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, use the frequency offset estimation value in the frequency offset interval adjacent to the boundary subinterval before the change as the current group 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纠正的分组数据中的频偏纠正结果结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,能够保证系统可靠、有效的工作。The network side device provided by the embodiment of the present invention obtains a relatively accurate frequency offset estimation result by combining the frequency offset correction result of the user in the packet data that has undergone frequency offset correction and the pilot data of the user in the current packet data, and according to The obtained frequency offset correction result performs frequency offset correction on the user's frequency domain data in the current packet data. Furthermore, the embodiment of the present invention divides the actual frequency offset range that the user may reach into several frequency offset intervals, so as to ensure the reliability and stability of frequency tracking and avoid interval jitter. The technical solutions of the embodiments of the present invention have less computational complexity, are less affected by timing errors and multi-user interference, and can ensure reliable and effective work 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、缓存或光盘中。The embodiment of the present invention can be realized by software, and the corresponding software program can be stored in a readable storage medium, for example, a hard disk, cache or optical disc of a 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 descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection of the present invention. within range.
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CN101547062B (en) * | 2009-03-03 | 2013-01-09 | 华为技术有限公司 | Method and device for correcting frequency deviation |
CN102137048B (en) * | 2010-01-22 | 2015-11-25 | 中兴通讯股份有限公司 | The method and system that a kind of frequency deviation is estimated |
CN102137049B (en) * | 2010-01-25 | 2015-05-20 | 中兴通讯股份有限公司 | Frequency offset estimation method and device for single time slot in long term evolution (LTE) system |
CN102468911B (en) * | 2010-11-11 | 2014-12-10 | 中兴通讯股份有限公司 | Decoding method of PUCCH and apparatus thereof |
CN102104563B (en) * | 2010-12-02 | 2013-10-02 | 华为技术有限公司 | Frequency control method and device |
CN102571647B (en) * | 2010-12-27 | 2014-11-05 | 中兴通讯股份有限公司 | Frequency offset estimation method and device |
CN103139114B (en) * | 2011-11-22 | 2016-12-07 | 华为技术有限公司 | The method and apparatus that a kind of automatic frequency controls |
CN104243372B (en) * | 2013-06-07 | 2019-03-12 | 中兴通讯股份有限公司 | The method and apparatus of offset estimation |
CN104243380A (en) * | 2013-06-09 | 2014-12-24 | 普天信息技术研究院有限公司 | Method for uplink frequency synchronization |
CN105099963B (en) * | 2014-04-24 | 2018-07-20 | 华为技术有限公司 | A kind of device and method of offset estimation |
CN105323199B (en) * | 2014-07-11 | 2019-02-12 | 普天信息技术有限公司 | An Uplink Frequency Offset Estimation Method |
CN105337909B (en) * | 2014-08-07 | 2020-02-14 | 中兴通讯股份有限公司 | Frequency offset estimation method and device |
CN104581975B (en) * | 2015-02-09 | 2018-04-20 | 武汉虹信通信技术有限责任公司 | A kind of frequency deviation processing method and system based on LTE |
CN107317780A (en) * | 2016-04-26 | 2017-11-03 | 中兴通讯股份有限公司 | A kind of frequency deviation estimating method and device |
WO2018040056A1 (en) * | 2016-09-01 | 2018-03-08 | 华为技术有限公司 | Frequency shift correction method and related device |
CN107359941B (en) * | 2017-08-02 | 2020-03-20 | 哈尔滨工业大学深圳研究生院 | Method for monitoring and correcting intermediate frequency offset cycle slip in real time in optical communication system |
CN110191074B (en) * | 2018-02-23 | 2021-07-02 | 中兴通讯股份有限公司 | Data demodulation method and device |
CN114257479B (en) * | 2020-09-23 | 2023-09-22 | 紫光展锐(重庆)科技有限公司 | Frequency offset estimation method and device, storage medium and terminal |
CN116455719B (en) * | 2023-06-16 | 2023-09-05 | 南京创芯慧联技术有限公司 | Frequency offset estimation method, device, communication equipment and readable storage medium |
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