WO2012055344A1 - 估计窄带干扰的方法、装置及接收设备 - Google Patents

估计窄带干扰的方法、装置及接收设备 Download PDF

Info

Publication number
WO2012055344A1
WO2012055344A1 PCT/CN2011/081227 CN2011081227W WO2012055344A1 WO 2012055344 A1 WO2012055344 A1 WO 2012055344A1 CN 2011081227 W CN2011081227 W CN 2011081227W WO 2012055344 A1 WO2012055344 A1 WO 2012055344A1
Authority
WO
WIPO (PCT)
Prior art keywords
signal
narrowband interference
prediction
estimating
narrowband
Prior art date
Application number
PCT/CN2011/081227
Other languages
English (en)
French (fr)
Inventor
杨赞
赵玉萍
刘青
Original Assignee
华为技术有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 华为技术有限公司 filed Critical 华为技术有限公司
Publication of WO2012055344A1 publication Critical patent/WO2012055344A1/zh

Links

Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00Modulated-carrier systems
    • H04L27/26Systems using multi-frequency codes
    • H04L27/2601Multicarrier modulation systems
    • H04L27/2647Arrangements specific to the receiver only
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04JMULTIPLEX COMMUNICATION
    • H04J11/00Orthogonal multiplex systems, e.g. using WALSH codes
    • H04J11/0023Interference mitigation or co-ordination
    • H04J11/0066Interference mitigation or co-ordination of narrowband interference
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00Modulated-carrier systems
    • H04L27/26Systems using multi-frequency codes
    • H04L27/2601Multicarrier modulation systems
    • H04L27/2647Arrangements specific to the receiver only
    • H04L27/2649Demodulators
    • H04L27/265Fourier transform demodulators, e.g. fast Fourier transform [FFT] or discrete Fourier transform [DFT] demodulators
    • H04L27/26522Fourier transform demodulators, e.g. fast Fourier transform [FFT] or discrete Fourier transform [DFT] demodulators using partial FFTs

Definitions

  • the present invention relates to the field of wireless communication technologies, and in particular, to a method, a device, and a receiving device for estimating narrowband interference.
  • OFDM is a broadband communication technology widely used in the field of wireless communication. It is widely used in wireless communication systems due to its characteristics of anti-multipath, flexible resource allocation, and high spectrum utilization.
  • An OFDM system typically includes an OFDM transmitting device and an OFDM receiving device.
  • the data to be transmitted will be modulated in mutually orthogonal subcarriers by using an Inverse Fast Fourier Transform (IFFT), and processed by the signal plus cyclic prefix, and then transmitted.
  • IFFT Inverse Fast Fourier Transform
  • the OFDM receiving apparatus after the received signal is subjected to de-cyclic prefixing, FFT conversion, equalization, and signal decision processing, the original transmission data is demodulated. If there is narrowband interference, the data on the interfered subcarriers will not be correctly demodulated; and because the interference value is generally not orthogonal to the data subcarriers, the interference energy will spread to other subcarriers. Therefore, when narrowband interferes When the intensity and bandwidth are relatively large, the OFDM receiving apparatus will not be able to correctly demodulate the transmitted data, and the performance of the OFDM system will be greatly reduced.
  • IFFT Inverse Fast Fourier Transform
  • a narrowband interference cancellation method for an OFDM system based on a prediction error filter is provided.
  • the principle of the method is to pass a narrow band.
  • the interfering signal is predicted to cancel the predicted narrowband interfering signal in the received signal.
  • the PEF narrowband interference cancellation method requires that the background signal of the prediction filter has a characteristic of approximate white noise, otherwise the predicted narrowband interference signal will have an estimation error.
  • a part of the null subcarriers are usually used as the guard bands in the effective subcarriers.
  • the introduced null subcarriers are significantly different from the actual effective subcarriers in signal characteristics, so that the prediction filter can not meet the requirements of approximate white noise when estimating and predicting narrowband interference signals, resulting in the error prediction filter being inaccurate.
  • the narrowband interference signal in the received signal is predicted, and the part of the guard band brought by the null subcarrier brings a large estimation error to the prediction filter.
  • Embodiments of the present invention provide a method, an apparatus, and a receiving device for estimating narrowband interference, which are used to solve the problem of the introduction of a null subband interference as a guard band in an existing PEF-based narrowband interference cancellation method.
  • the prediction of narrowband interference presents the problem of estimation error.
  • a method of estimating narrowband interference comprising:
  • the narrowed-band interference signal is subjected to prediction processing on the nulled subcarrier signal by an error prediction filter to obtain a narrowband interference prediction signal.
  • a device for estimating narrowband interference comprising:
  • a sampling rate conversion module configured to perform sampling rate conversion processing on a ratio of a number of effective subcarriers to a total number of subcarriers, and generate a blanking subcarrier signal, where the received signal is a signal transmitted by the received orthogonal frequency division multiplexing transmitting device;
  • a narrowband interference signal prediction module configured to perform prediction processing of the narrowband interference signal on the nulled subcarrier signal by using an error prediction filter, to obtain a narrowband interference prediction signal of the received signal, and to provide a receiving device
  • the method further includes: the foregoing apparatus for estimating narrowband interference, wherein the apparatus for estimating narrowband interference is connected to the receiving module, and configured to perform prediction processing of a narrowband interference signal on a received signal received by the receiving module.
  • a method, device and receiving device for estimating narrowband interference provided by an embodiment of the present invention
  • the OFDM receiving apparatus before the narrowband interference signal in the received signal is predicted by the error prediction filter, sampling rate conversion processing is performed on the received signal, and the sampling rate used is a ratio of the number of null subcarriers to the number of effective subcarriers, thereby
  • the spectrum of the received signal can be effectively concentrated in the effective subcarrier, and the interference of the introduced null subcarrier to the effective subcarrier signal is removed, so that the prediction result of the error prediction filter for the narrowband interference signal is more accurate, and the null can be effectively solved.
  • the narrowband interference signal estimation error problem brought by the introduction of the carrier improves the performance of the OFDM receiving apparatus.
  • 1 is a flowchart of a method for estimating narrowband interference according to an embodiment of the present invention
  • FIG. 2 is a flowchart of another method for estimating narrowband interference according to an embodiment of the present invention. Schematic diagram of an algorithm for estimating narrowband interference in an example;
  • FIG. 6 is a schematic structural diagram of an apparatus for estimating narrowband interference according to an embodiment of the present invention
  • FIG. 7 is a schematic structural diagram of another apparatus for estimating narrowband interference according to an embodiment of the present invention
  • FIG. 1 is a flowchart of a method for estimating narrowband interference according to an embodiment of the present invention. As shown in FIG. 1, the method in this embodiment includes the following steps:
  • Step 100 Perform sampling rate conversion processing on the ratio of the number of effective subcarriers to the total number of subcarriers, and obtain a nulled subcarrier signal.
  • the narrowband interference estimation method of the embodiment of the present invention is implemented based on the PEF narrowband interference cancellation method.
  • the OFDM receiving apparatus predicts the narrowband interference signal in the received signal by the error prediction filter, in order to remove the interference of the null subcarrier introduced in the received signal to the effective subcarrier, the background signal in the input error prediction filter is guaranteed to satisfy the approximate white
  • the requirements of the noise characteristics ensure the correctness of the prediction result of the narrowband interference signal, and the sampling rate conversion processing is performed on the received signal.
  • the total number of subcarriers in the OFDM system is N
  • the total number of effective subcarriers is V.
  • the OFDM receiving apparatus performs a sampling rate conversion process on the input received signal by using a sampling rate of V/N. The received signal is converted to a null subcarrier signal.
  • the OFDM system may include an OFDM transmitting apparatus and an OFDM receiving apparatus
  • the received signal may be a signal sent by the OFDM transmitting apparatus to the OFDM receiving apparatus, because the sampling rate of the V/N is adopted, after the sampling rate conversion processing
  • the spectrum segment of the received signal is concentrated in the effective low frequency portion of the effective subcarrier, which is equivalent to removing the null subcarrier portion of the received signal except the effective subcarrier portion.
  • the inventors of the present invention have found that in the PEF-based narrowband interference cancellation method, the reason why the background signal cannot satisfy the approximate white noise characteristic is that: the space subcarrier and the effective subcarrier are significantly different in signal characteristics, thus removing the null subcarrier portion.
  • the de-spaced subcarrier signal can provide an approximate error-free background signal to the error prediction filter, which effectively overcomes the problem of narrowband interference signal estimation error caused by the introduction of null subcarriers.
  • Step 101 Perform prediction processing on the nulled subcarrier signal by using an error prediction filter to obtain a narrowband interference prediction signal of the received signal.
  • the OFDM receiving apparatus may use an error prediction filter to perform prediction of the narrowband interference signal on the nulled subcarrier signal from which the null subcarrier portion is removed, to obtain a received signal.
  • the narrowband interference prediction signal in the middle.
  • the signal prediction process is performed based on the nulling subcarrier signal. Since the nulled subcarrier signal meets the characteristic requirements of approximate white noise, the narrowband interference prediction signal predicted by the error prediction filter does not have a large estimation error, and is based on The narrowband interference cancellation method performed by the narrowband interference prediction signal can also well eliminate the narrowband interference signal in the received signal.
  • the sampling rate conversion processing is performed on the received signal by predicting the narrowband interference signal in the received signal by the error prediction filter in the OFDM receiving apparatus, and the sampling rate is adopted.
  • the interference of the null subcarriers on the received signal makes the prediction result of the narrowband interference signal more accurate by the error prediction filter, which can effectively solve the narrowband interference signal estimation error caused by the introduction of the null subcarrier and improve the performance of the OFDM receiver.
  • FIG. 2 is a flowchart of another method for estimating narrowband interference according to an embodiment of the present invention. As shown in FIG. 2, the method in this embodiment includes the following steps:
  • Step 200 Perform sampling rate conversion processing on the ratio of the number of effective subcarriers to the total number of subcarriers, and generate a blanking subcarrier signal.
  • the received signal prior to narrowband interference received signal rcp n signal in a prediction for the spectrum of the received signal is concentrated in the active subcarriers portion of the received signal, in order to remove the received spectral characteristics of null subcarriers in the signal, for
  • the received signal is subjected to a sampling rate conversion process in which the sampling rate is a ratio of the effective subcarrier number V to the total number of subcarriers N, and the received signal, ⁇ , is converted into a nulling subcarrier signal r.
  • Step 201 Perform prediction processing on the nulled subcarrier signal by using an error prediction filter to obtain a narrowband interference prediction signal.
  • the method for predicting the narrowband interference signal in the nulled subcarrier signal by the error prediction filter in this embodiment may be as follows:
  • Step 2010 sampling a continuous signal of a preset length of the error prediction filter by sampling the depleted subcarrier signal to obtain sampling data;
  • the preset length of the error prediction filter for performing prediction of the narrowband interference signal in the present embodiment is L
  • the narrowband interference signal in the nulled subcarrier signal after the sample rate conversion processing is predicted by the error prediction filter
  • the continuous signal sampling can be performed on the null subcarrier signal, ⁇ first.
  • the shorted subcarrier signal ⁇ ⁇ is sampled by a continuous signal with a sampling length L to obtain sampling data 2 , .. rcp n , — ] ⁇ .
  • the value of the preset length L of the error prediction filter may be based on a compromise between the prediction performance of the narrowband interference signal and the complexity of the prediction process. Choose. A larger L means that the predicted performance is better, that is, the prediction of the narrowband interference signal is more accurate, but the complexity is also higher.
  • Step 2011, performing adaptive filtering processing on the sampled data, and extracting a narrowband interference prediction signal from the sampled data;
  • the OFDM receiving apparatus can predict the narrowband interference signal for the sampled data [, ⁇ , -2 ..1 ⁇ , - J T by an error prediction filter of length L.
  • the prediction of the narrowband interference signal by the OFDM receiving apparatus may be performed based on an adaptive filtering processing method.
  • the error prediction filter is for sampling data
  • the different de-empty subcarrier signals r OT ⁇ the adopted filter coefficients can be adaptively adjusted according to the characteristics of the corresponding de-vacuum subcarrier signals, ⁇ , and thus from the sampled data 2 , ... rcp , n , - ] ⁇ different depleted subcarrier signals, ⁇ , extract the common signal, which is the prediction signal for narrowband interference, ie narrowband interference prediction signal i PEF , n ,.
  • the adaptive filtering process is only one of the methods for predicting the narrowband interference signal, and other filtering processing modes other than the adaptive filtering process may also be applied to the embodiment of the present invention.
  • the embodiments of the present invention are not limited thereto.
  • FIG. 3 is a schematic diagram of an algorithm in a method for estimating narrowband interference according to an embodiment of the present invention.
  • is subjected to a sampling rate conversion of a sampling rate of V/N to obtain a sample data [, ⁇ , — ⁇ ⁇ , ⁇ of a length L after the nulled subcarrier signal rq) , n is obtained . , - 2 , .., , - ] ⁇ is input to the error prediction filter.
  • the adaptive filter performs adaptive filtering processing. For each nulling subcarrier signal r OT n , the corresponding adaptive filter coefficient is w*.
  • the adaptive filtering process is essentially a weighted combining process on the signal. After performing weighted combining processing on successive multiple de- vacuum subcarrier signals ⁇ , ⁇ , the commonality of the consecutive plurality of blanked subcarrier signals, ⁇ , The signal will be extracted and the narrowband interference prediction signal i PEF , n , will be extracted. Further, in the present embodiment, the adaptive filter to the sample data [, ⁇ , - ⁇ ⁇ , ⁇ , - 2, ... rcp, n, -] T adaptive filtering process performed in each The null subcarrier signal r OT n is used, and the adaptive filter coefficient can follow the coefficient update algorithm of the Least mean square (LMS) algorithm.
  • LMS Least mean square
  • i PEF , n , Rj P W* , where the sampled data 2 , . . . , ⁇ , — ] ⁇ , W* corresponds to the sampled data.
  • the adaptive filter coefficient, and W*, the adaptive filter coefficient W* can follow the following coefficient update formula defined by the LMS algorithm:
  • the W* on the right side of the formula is the upper set of the adaptive filter
  • the adaptive filter coefficient used in the sampled data; 7 is the adjustment step size, and the value of 7 is related to the characteristic change rate of the nulled subcarrier signal, ⁇ , in the sampled data, specifically, the value must be guaranteed to be blanked subcarrier signal.
  • the updated speed matches the speed at which the signal characteristics change.
  • the corresponding adaptive filter coefficient W* used by the adaptive filter may be based on the corresponding set
  • the filter coefficients and adjustment step sizes of the sampled data, and adaptive adjustments and changes as the set of sampled data Re P are varied to adapt to each of the depleted subcarrier signals, ⁇ , in the sampled data of the set.
  • the LMS algorithm-based adaptive filter coefficient update algorithm used in the adaptive filter is not a unique coefficient update algorithm that can predict narrowband interference, and may also be used in the embodiment of the present invention.
  • the adaptive filter coefficients are adjusted and updated by using other coefficient update algorithms, but the embodiment of the present invention does not limit this.
  • the narrowband interference prediction signal can be removed in the received signal by the following manner.
  • Step 202 Perform a sampling rate conversion process in which the narrowband interference prediction signal is sampled as a ratio of the total number of subcarriers to the number of effective subcarriers, to obtain a narrowband interference prediction recovery signal.
  • the OFDM receiving apparatus may first perform sampling rate recovery processing on the narrowband interference prediction signal iPEF , n according to a processing method opposite to the sampling rate conversion processing.
  • the narrowband interference prediction signal i PEF , n is restored to a sampling frequency equal to the original received signal r OT n , and then the narrowband interference signal is removed.
  • the sampling rate used in the sampling rate recovery process of this step should be the reciprocal of the sampling rate used in the sampling rate conversion processing step, specifically the ratio N/V of the total number of subcarriers N to the effective number of subcarriers V. .
  • a narrowband interference prediction recovery signal i PEF , n is obtained , and the narrowband interference prediction recovery signal i is obtained.
  • PEF , n is a narrowband interference signal in the predicted received signal.
  • Step 203 Subtracting the received signal from the narrowband interference prediction and recovery signal to obtain a narrowband interference signal that eliminates narrowband interference;
  • the OFDM receiving apparatus subtracts the received signal, ⁇ , from the predicted narrowband interference prediction recovery signal iPEF , n , which is equivalent to removing the narrowband interference signal from the received signal fcpn . Since the above prediction process for the narrowband interference signal is performed based on the sampled data composed of the nulled subcarrier signal, the nulled subcarrier signal ⁇ ⁇ satisfies the characteristics of the approximate white noise on the basis of eliminating the interference of the null subcarrier to the effective subcarrier. Therefore, the narrowband interference signal predicted by the adaptive filter is relatively accurate at this time, and a large estimation error does not occur, so that the narrowband interference cancellation method based on the narrowband interference prediction signal can also receive the signal. The narrowband interference signal in the middle is well eliminated, and the receiving performance of the OFDM receiving apparatus is greatly improved.
  • the comparison may correspond to the same Signal to Interference Ratio (SIR), in different receiving channels, for example, in an Additive White Gaussian Noise (AWGN) channel or a vehicle.
  • SIR Signal to Interference Ratio
  • AWGN Additive White Gaussian Noise
  • VA Vehicle A
  • the conventional PEF narrowband interference cancellation method and the narrowband interference cancellation method of the embodiment of the present invention are respectively used, the obtained narrowband interference resistance is obtained when the same received signal is received.
  • the conventional PEF narrowband interference cancellation method and the method for estimating the anti-interference ability of the method for estimating narrowband interference according to the embodiment of the present invention are compared.
  • the narrowband interference cancellation method according to the embodiment of the present invention is compared with the conventional one.
  • the received signal to interference plus noise ratio (Signal to Interference plus Noise Ratio, SINR) is significantly better than the traditional PEF narrowband interference cancellation method.
  • FIG. 5B corresponds to a VA channel and
  • the conventional PEF narrowband interference cancellation method and the method for estimating the narrowband interference of the embodiment of the present invention have a comparison result of the error rate simulation.
  • the narrowband interference cancellation method of the embodiment of the present invention is used.
  • the error rate of the received signal is also significantly better than the traditional PEF narrowband interference cancellation method.
  • Step 204 Perform de-circulation prefix, fast Fourier transform, equalization, and signal decision processing on the de-narrowband interference signal in sequence to obtain a transmission signal.
  • the OFDM receiving apparatus can sequentially perform cyclic prefix, FFT transform, equalization, and signal decision processing on the received signal after the narrowband interference, and finally obtain the predicted OFDM transmitting apparatus.
  • the transmitted signal sent.
  • the predicted transmission signal effectively eliminates the narrowband interference signal, and overcomes the influence of the narrowband interference caused by the null subcarrier on the performance of the OFDM system.
  • the method for estimating narrowband interference in this embodiment is adopted in an OFDM receiving apparatus Before the error prediction filter predicts the narrowband interference signal in the received signal, the sampled rate conversion process is performed on the received signal, and the sampling rate used is a ratio of the number of null subcarriers to the number of effective subcarriers, so that the received signal can be effectively received.
  • the spectrum is concentrated in the effective subcarriers, and the interference of the introduced null subcarriers on the received signals is removed, so that the prediction result of the error prediction filter for the narrowband interference signals is more accurate, and the narrowband interference signals brought by the introduction of the null subcarriers can be effectively solved.
  • the error problem is estimated to improve the performance of the OFDM receiving apparatus.
  • the adaptive filtering-based prediction method adaptively predicts the narrowband interference signal, and predicts the narrowband interference signal from the received signal.
  • the removal can overcome the influence of narrowband interference on the performance of the OFDM system, and further improve the signal receiving performance of the OFDM receiving apparatus.
  • FIG. 6 is a schematic structural diagram of an apparatus for estimating narrowband interference according to an embodiment of the present invention.
  • the apparatus for estimating narrowband interference in this embodiment includes a sampling rate conversion module 11 and a narrowband interference signal prediction module 12.
  • the sampling rate conversion module 11 is configured to perform sampling rate conversion processing on the ratio of the number of effective subcarriers to the total number of subcarriers, and generate a blanking subcarrier signal to concentrate the spectrum of the received signal on the effective subcarrier.
  • the received signal is specifically a signal sent by the received OFDM transmitting apparatus; the narrowband interference signal predicting module 12 is configured to perform narrowband interference signal prediction processing on the nulled subcarrier signal generated by the sampling rate conversion module 11 by using an error prediction filter, A narrowband interference prediction signal of the received signal is obtained.
  • the apparatus for estimating narrowband interference performs sampling rate conversion processing on the received signal by predicting a narrowband interference signal in the received signal based on the error prediction filter, and adopts a sampling rate of a null subcarrier number and an effective sub
  • the ratio of the number of carriers can effectively concentrate the spectrum of the received signal in the effective subcarrier, and remove the interference of the introduced null subcarrier to the received signal, so that the prediction result of the error prediction filter for the narrowband interference signal is more accurate, and thus Effectively solve the problem of narrowband interference signal estimation error caused by the introduction of null subcarriers, improve
  • FIG. 7 is a schematic structural diagram of another apparatus for estimating narrowband interference according to an embodiment of the present invention.
  • the apparatus for estimating narrowband interference in this embodiment further includes The sampling rate recovery module 13 and the narrowband interference removal module 14.
  • the sampling rate recovery module 13 is configured to: after the narrowband interference signal prediction module 12 predicts the narrowband interference prediction signal, the sampling rate conversion process of the ratio of the number of effective subcarriers to the number of null subcarriers is generated by the narrowband interference prediction signal, and generated.
  • the narrowband interference prediction recovery signal is used to subtract the narrowband interference prediction recovery signal generated by the sampling rate recovery module 13 in the received signal to obtain a narrowband interference signal with narrowband interference eliminated.
  • the narrowband interference signal prediction module 12 in this embodiment may further include a signal sampling submodule 121 and an adaptive filtering processing submodule 122.
  • the signal sampling sub-module 121 is configured to sample the continuous signal of the preset length of the error prediction filter by using the shortned subcarrier signal to obtain sampling data.
  • the adaptive filtering processing sub-module 122 is configured to the signal sampling sub-module 121. The sampled sampled data is subjected to adaptive filtering processing, and the narrowband interference prediction signal is extracted from the sampled data.
  • the adaptive filtering processing sub-module 122 is further configured to perform adaptive filtering processing on the sampling data sampled by the signal sampling sub-module 121 by using an error prediction filter whose adaptive filtering coefficient follows the LMS algorithm.
  • W* is an adaptive filter coefficient, which is an adjustment step size
  • is a blanking subcarrier.
  • Wave signal, i PEF , n narrowband interference prediction signal, Rc P is sampled data.
  • the apparatus for estimating narrowband interference in this embodiment may further include a processing module 15 for subtracting the received signal from the narrowband interference prediction and recovery signal by the narrowband interference removal module 14 to obtain a narrowband interference prediction signal, and then sequentially
  • the narrowband interference signal is subjected to de-cycle prefix, fast Fourier transform, equalization, and signal decision processing to obtain a transmitted signal transmitted by the predicted OFDM transmitting apparatus.
  • the apparatus for estimating narrowband interference in this embodiment performs sampling rate conversion processing on a received signal by predicting a narrowband interference signal in a received signal by an error prediction filter in an OFDM receiving apparatus, and adopts a sampling rate The ratio of the number of null subcarriers to the number of effective subcarriers, so that the spectrum of the received signal can be effectively concentrated in the effective subcarriers, and the interference of the introduced null subcarriers on the received signal is removed, so that the prediction result of the error prediction filter for the narrowband interference signal is obtained. More accurate, it can effectively solve the narrowband interference signal estimation error caused by the introduction of null subcarriers, and improve the performance of the OFDM receiving device.
  • the adaptive prediction method based on the adaptive filter is used to adaptively predict the narrowband interference signal, and the predicted narrowband interference signal is removed from the received signal, and the performance of the OFDM system can be overcome by narrowband interference. The effect of further improving the signal receiving performance of the OFDM receiving apparatus.
  • FIG. 8 is a schematic structural diagram of a receiving device according to an embodiment of the present invention.
  • the receiving device of this embodiment includes: a receiving module 1 and a device 2 for estimating narrowband interference, and the device 2 for estimating narrowband interference is connected to the receiving module 1 for performing receiving signals received by the receiving module 1. Predictive processing of narrowband interfering signals.
  • all the functional modules involved in the apparatus 2 for estimating the narrowband interference, and the specific working processes involved therein may refer to the method for estimating the narrowband interference and the related content disclosed in the embodiment related to the apparatus for estimating the narrowband interference, I will not comment here.
  • the receiving device in this embodiment may specifically be an OFDM receiving device in an OFDM system.
  • the receiving device of this embodiment is applied to an OFDM receiving apparatus, and performs sampling rate conversion processing on the received signal by predicting a narrowband interference signal in the received signal by an error prediction filter, and the sampling rate used is a null subcarrier.
  • the ratio of the number to the number of effective subcarriers thereby effectively concentrating the spectrum of the received signal in the effective subcarrier, removing the interference of the introduced null subcarrier on the received signal, so that the prediction result of the error prediction filter for the narrowband interference signal is more Accurately and effectively solve the narrowband interference signal estimation error caused by the introduction of null subcarriers, and improve the performance of the OFDM receiver.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Noise Elimination (AREA)

Abstract

本发明提供一种估计窄带干扰的方法、装置及接收设备。该方法包括:对接收信号进行采样率为有效子载波数与子载波总数的比值的采样率转换处理,得到去空子载波信号(100),该接收信号为接收的OFDM发送装置发送的信号;通过误差预测滤波器对去空子载波信号进行窄带干扰信号的预测处理,得到接收信号的窄带干扰预测信号(101)。本发明有效地去除了引入的空子载波对有效子载波信号的干扰,解决了空子载波的引入带来的窄带干扰信号估计误差问题,提高了OFDM接收装置的性能。

Description

估计窄带干扰的方法、 装置及接收设备 本申请要求于 2010 年 10 月 25 日提交中国专利局、 申请号为 201010526988.7、 发明名称为"估计窄带干扰的方法、 装置及接收设备"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 本发明涉及无线通讯技术领域, 具体涉及一种估计窄带干扰的方法、 装置及接收设备。
背景技术 正交频分复用 ( Orthogonal Frequency Division Multiplexing , 筒称
OFDM )是无线通信领域中获得广泛应用的一种宽带通信技术, 由于具有抗 多径、 资源配置灵活、 频谱利用率高等特点, 目前被广泛应用于无线通信 系统中。
OFDM系统通常包括 OFDM发射装置和 OFDM接收装置。 在 OFDM发射 装置中, 待发送数据均将利用快速傅里叶反变换 (Inverse Fast Fourier Transform, 筒称 IFFT )被调制在相互正交的子载波中, 并经信号加循环前 缀处理后, 被发送给 OFDM接收装置。 而在 OFDM接收装置中, 接收信号被 进行去循环前缀、 FFT变换、 均衡以及信号判决等处理后, 又将解调得到原 始的发送数据。 若存在窄带干扰, 将造成受干扰的子载波上数据无法正确 解调; 并且由于干扰值一般与数据子载波没有正交关系, 干扰能量将会扩 散到其它子载波上, 因此, 当窄带干扰的强度和带宽比较大时, OFDM接收 装置将无法正确地解调出发送数据, OFDM系统的性能也将被会大大降低。
现有技术中提供了一种基于误差预测滤波器( Prediction Error Filter, 筒 称 PEF )的 OFDM系统窄带干扰消除方法, 该方法的原理在于通过对窄带 干扰信号进行预测, 以在接收信号中将预测到的窄带干扰信号消除。 为了 能够准确地预测出接收信号中的窄带干扰信号大小, PEF 窄带干扰消除方 法要求预测滤波器的背景信号具有近似白噪的特征, 否则预测出的窄带干 扰信号将出现估计误差。 但是在大多数 OFDM系统中, 为了对有效子载波 进行保护, 通常会在有效子载波中间隔采用一部分空子载波作为保护频带。 引入的空子载波与实际的有效子载波在信号特性上存在明显区别, 使得预 测滤波器在对窄带干扰信号进行估计预测时, 背景信号无法满足近似白噪 的要求, 从而导致误差预测滤波器无法准确地预测出接收信号中的窄带干 扰信号, 由空子载波带来的这部分保护频带给预测滤波器带来了较大的估 计误差。
发明内容 本发明实施例提供了一种估计窄带干扰的方法、 装置及接收设备, 用 以解决现有的基于 PEF的窄带干扰消除方法中, 由于作为保护频带的空子 载波的引入而带来的对窄带干扰的预测出现估计误差的问题。
本发明实施例具体可以通过如下技术方案实现:
一方面, 提供了一种估计窄带干扰的方法, 该方法包括:
对接收信号进行采样率为有效子载波数与子载波总数的比值的采样率 转换处理, 生成去空子载波信号, 所述接收信号为接收的正交频分复用发 送装置发送的信号;
通过误差预测滤波器对所述去空子载波信号进行窄带干扰信号的预测 处理, 得到窄带干扰预测信号。
还提供了一种估计窄带干扰的装置, 该装置包括:
采样率转换模块, 用于对接收信号进行采样率为有效子载波数与子载 波总数的比值的采样率转换处理, 生成去空子载波信号, 所述接收信号为 接收的正交频分复用发送装置发送的信号;
窄带干扰信号预测模块, 用于通过误差预测滤波器对所述去空子载波 信号进行窄带干扰信号的预测处理, 得到所述接收信号的窄带干扰预测信 另一方面, 还提供了一种接收设备, 包括接收模块, 还包括: 上述的估计窄带干扰的装置, 所述估计窄带干扰的装置与所述接收模 块连接, 用于对所述接收模块接收到的接收信号进行窄带干扰信号的预测 处理。
本发明实施例提供的估计窄带干扰的方法、 装置及接收设备, 通过在
OFDM接收装置中, 在通过误差预测滤波器对接收信号中的窄带干扰信号 进行预测之前, 对接收信号进行采样率转换处理, 且采用的采样率为空子 载波数和有效子载波数的比值, 从而可以有效地将接收信号的频谱集中在 有效子载波中, 去除引入的空子载波对有效子载波信号的干扰, 使得误差 预测滤波器对窄带干扰信号的预测结果更加准确, 也就可以有效地解决空 子载波的引入带来的窄带干扰信号估计误差问题, 提高 OFDM接收装置的 性能。 附图说明 图 1为本发明实施例提供的一种估计窄带干扰的方法的流程图; 图 2为本发明实施例提供的另一种估计窄带干扰的方法的流程图; 图 3为本发明实施例的估计窄带干扰的方法中的算法示意图; 图 4A为对应于 AGWN信道及 SIR=0dB的情况下,传统的 PEF窄带干 扰消除方法和本发明实施例的估计窄带干扰的方法的抗干扰能力仿真对比 结果示意图;
图 4B为对应于 AGWN信道及 SIR=5dB的情况下,传统的 PEF窄带干 扰消除方法和本发明实施例的估计窄带干扰的方法的抗干扰能力仿真对比 结果示意图;
图 5A为对应于 VA信道及 SIR=0dB的情况下, 传统的 PEF窄带干扰 消除方法和本发明实施例的估计窄带干扰的方法的误码率仿真对比结果示 意图;
图 5B为对应于 VA信道及 SIR=5dB的情况下, 传统的 PEF窄带干扰 消除方法和本发明实施例的估计窄带干扰的方法的误码率仿真对比结果示 意图;
图 6为本发明实施例提供的一种估计窄带干扰的装置的结构示意图; 图 7为本发明实施例提供的另一种估计窄带干扰的装置的结构示意图; 图 8为本发明实施例提供的一种接收设备的结构示意图。 具体实施方式 为使本发明实施例的目的、 技术方案和优点更加清楚, 下面将结合本 发明实施例中的附图, 对本发明实施例中的技术方案进行清楚、 完整地描 述, 显然, 所描述的实施例是本发明一部分实施例, 而不是全部的实施例。 基于本发明中的实施例, 本领域普通技术人员在没有做出创造性劳动前提 下所获得的所有其他实施例, 都属于本发明保护的范围。
图 1为本发明实施例提供的一种估计窄带干扰的方法的流程图,如图 1 所示, 本实施例的方法包括如下步骤:
步骤 100,对接收信号进行采样率为有效子载波数与子载波总数的比值 的采样率转换处理, 得到去空子载波信号;
本发明实施例的窄带干扰估计方法基于 PEF 窄带干扰消除方法而实 现。 在 OFDM接收装置通过误差预测滤波器对接收信号中的窄带干扰信号 进行预测之前, 为了去除接收信号中引入的空子载波对有效子载波的干扰, 保证输入误差预测滤波器中的背景信号满足近似白噪特征的要求, 从而保 证窄带干扰信号预测结果的正确性, 对接收信号进行了采样率转换处理。 具体地, 假设 OFDM系统中的子载波总数为 N, 有效子载波总数为 V, 在 本步骤中, OFDM接收装置采用 V/N的采样率, 对输入的接收信号进行采 样率转换处理, 以将接收信号转换为去空子载波信号。
其中,在 OFDM系统中可以包括 OFDM发送装置和 OFDM接收装置, 而上述的接收信号可以是由 OFDM发送装置发送给 OFDM接收装置的信 由于采用了 V/N的采样率, 经过采样率转换处理后的接收信号的频谱 段被集中在了有效子载波的有效低频部分, 相当于去除了接收信号中除有 效子载波部分的空子载波部分。 本发明的发明人发现, 在基于 PEF的窄带 干扰消除方法中, 导致背景信号无法满足近似白噪特征的原因在于: 空子 载波与有效子载波在信号特性上的明显区别, 因而去除了空子载波部分的 去空子载波信号能够给误差预测滤波器提供近似无特征偏差的背景信号, 有效地克服解决了空子载波的引入带来的窄带干扰信号估计误差问题。
步骤 101 ,通过误差预测滤波器对去空子载波信号进行窄带干扰信号的 预测处理, 得到接收信号的窄带干扰预测信号。
在通过采样率转换处理, 对接收信号进行空子载波部分的去除后, OFDM接收装置可以采用误差预测滤波器, 对去除了空子载波部分的去空 子载波信号进行窄带干扰信号的预测, 以得到接收信号中的窄带干扰预测 信号。 该信号预测过程基于去空子载波信号而进行, 由于去空子载波信号 符合近似白噪的特征要求, 因而此时采用误差预测滤波器预测的窄带干扰 预测信号不会出现较大的估计误差, 进而基于该窄带干扰预测信号进行的 窄带干扰消除方法也能对接收信号中的窄带干扰信号进行很好的消除。
本实施例的估计窄带干扰的方法, 通过在 OFDM接收装置中, 在通过 误差预测滤波器对接收信号中的窄带干扰信号进行预测之前, 对接收信号 进行采样率转换处理, 且采用的采样率为空子载波数和有效子载波数的比 值, 从而可以有效地将接收信号的频谱集中在有效子载波中, 去除引入的 空子载波对接收信号的干扰, 使得误差预测滤波器对窄带干扰信号的预测 结果更加准确, 也就可以有效地解决空子载波的引入带来的窄带干扰信号 估计误差问题, 提高 OFDM接收装置的性能。
图 2为本发明实施例提供的另一种估计窄带干扰的方法的流程图, 如 图 2所示, 本实施例的方法包括如下步骤:
步骤 200,对接收信号进行采样率为有效子载波数与子载波总数的比值 的采样率转换处理, 生成去空子载波信号;
本实施例中, 在对接收信号 rcp n中的窄带干扰信号进行预测之前, 为了 将接收信号的频谱集中在接收信号的有效子载波部分, 以去除掉接收信号 中的空子载波的频谱特性, 对接收信号进行了采样率为有效子载波数 V与 子载波总数 N的比值观的采样率转换处理,将接收信号 ,η转换为去空子 载波信号 r 。
步骤 201 ,通过误差预测滤波器对去空子载波信号进行窄带干扰信号的 预测处理, 得到窄带干扰预测信号;
在得到去空子载波信号后, 本实施例中通过误差预测滤波器对去空子 载波信号中的窄带干扰信号进行预测的方式可以如下:
步骤 2010, 对去空子载波信号进行采样长度为误差预测滤波器的预设 长度的连续信号采样, 得到采样数据;
假定本实施例中用于进行窄带干扰信号的预测的误差预测滤波器的预 设长度为 L,在通过误差预测滤波器对采样率转换处理后的去空子载波信号 中的窄带干扰信号进行预测时, 可以首先对去空子载波信号 ,η,进行连续的 信号采样。具体指根据误差预测滤波器的预设长度 L,对去空子载波信号 Γερ η, 进行采样长度为 L的连续信号的采样, 以得到采样数据 2,..rcp n,— ]τ
具体地, 实际应用中, 对于误差预测滤波器的预设长度 L的取值大小, 可以基于对窄带干扰信号的预测性能和预测过程的复杂度进行折衷的取值 选择。 L越大代表预测的性能越好, 即对窄带干扰信号的预测也越准确, 但 是复杂度也随之越高。
步骤 2011 , 对采样数据进行自适应滤波处理, 从采样数据中提取出窄 带干扰预测信号;
在对去空子载波信号 进行采样得到采样数据 i 2,... ]τ后,
OFDM 接收装置可以通过长度为 L 的误差预测滤波器, 对采样数据 [ ,η,— 2 ..1^,— JT进行窄带干扰信号的预测。 具体地, 本实施例中, OFDM 接收装置对窄带干扰信号的预测可以基于自适应的滤波处理方法而进行。 自适应滤波处理方法中,误差预测滤波器针对采样数据
Figure imgf000009_0001
中 的不同的去空子载波信号 rOT η ,所采用的滤波系数可以随着对应的去空子载 波信号 ,η,的特性而进行自适应的调整, 从而从采样数据 2,...rcp,n,— ]τ 的不同去空子载波信号 ,η,中提取出共性的信号, 该信号即为对窄带干扰的 预测信号, 即窄带干扰预测信号 iPEF,n,。
而需要说明的是, 本发明实施例中, 自适应滤波处理只是对窄带干扰 信号进行预测的其中一种方式, 除自适应滤波处理之外的其他滤波处理方 式也可以应用在本发明实施例, 本发明实施例并不对此进行限制。
具体地, 图 3为本发明实施例的估计窄带干扰的方法中的算法示意图。 如图 3所示, 在接收信号 ,η经过采样率为 V/N的采样率转换, 得到去空子 载波信号 rq),n,后, 长度为 L的采样数据 [ ,η,— ι ρ,η,— 2,.., ,— ]τ被输入至误差预测 滤波器, 在本实施例中具体指自适应滤波器中, 进行自适应滤波处理。 每 个去空子载波信号 rOT n,对应的自适应滤波系数为 w*。 自适应滤波处理实质上 为对信号的加权合并处理, 在对连续的多个去空子载波信号 Γερ,η,进行了加权 合并处理后, 该连续的多个去空子载波信号 ,η,中的共性信号将被提取出, 而提取得到窄带干扰预测信号 iPEF,n,。 进一步地, 在本实施例中, 自适应滤波器对采样数据 [ ,η,— ι Γερ,η,— 2,...rcp,n,— ]T 进行的自适应滤波处理过程中,对各个去空子载波信号 rOT n,采用的自适应滤 波系数可以遵循最小均方( Least mean square, 筒称 LMS )算法的系数更新 算法。 即若将自适应滤波器进行的自适应滤波处理表示为 iPEF,n, = RjPW* , 其 中 为 采样数据 2,..., ,η,— ]τ , W* 为对应 于采样数据
Figure imgf000010_0001
的自适应滤波系数, 且 W* , 该自适应滤波 系 数 W* 可以遵循 LMS 算法定义的 下述系 数更新公式: 上述系数更新公式中, 公式右侧的 W*为自适应滤波器的上一组采样数 据中所采用的自适应滤波系数; 7为调整步长, 7的取值与采样数据中的去 空子载波信号 ,η,的特性变化速率有关, 具体指该取值大小必须保证去空子 载波信号 。,更新的速度与信号特性变化的速度相匹配。 基于上述公式, 自 适应滤波器中, 对于每一组的采样数据 [ , i, ,— 2 JT , 自适应滤波器所 采用的对应的该自适应滤波系数 W*可以基于对应于上一组采样数据的滤波 系数和调整步长 , 以及随着本组采样数据 ReP的变化而进行自适应的调整 和变化, 以适配于本组的采样数据中的各去空子载波信号 ,η,。
需要说明的是, 本发明实施例中, 自适应滤波器中采用的基于 LMS算 法的自适应滤波系数更新算法并非为可以对窄带干扰进行预测的唯一的系 数更新算法, 本发明实施例中还可以采用其他的系数更新算法对自适应滤 波系数进行调整更新, 而本发明实施例并不对此进行限制。
进一步地, 在通过以上步骤预测得到对窄带干扰的信号, 即窄带干扰 预测信号 iPEF,n,后, 可以通过以下的方式在接收信号 中将该窄带干扰预测 信号进行去除。
步骤 202,将窄带干扰预测信号进行采样率为子载波总数与有效子载波 数的比值的采样率转换处理, 得到窄带干扰预测恢复信号; 为了在接收信号 rcp n中将该窄带干扰预测信号进行去除, OFDM接收装 置可以首先按照与采样率转换处理相反的处理方法, 对该窄带干扰预测信 号 iPEF,n,进行采样率恢复处理, 以将窄带干扰预测信号 iPEF,n,恢复到与原始接 收信号 rOT n相等的采样频率, 再进行窄带干扰信号的去除操作。 具体地, 本 步骤的采样率恢复处理中所采用的采样率应当为上述采样率转换处理步骤 中所采用的采样率的倒数, 具体为子载波总数 N与有效子载波数 V的比值 N/V。 如图 3所示, 在对窄带干扰预测信号 iPEF,n,进行采样率为 N/V的采样 率转换处理后, 将得到窄带干扰预测恢复信号 iPEF,n , 该窄带干扰预测恢复 信号 iPEF,n为经预测得到的接收信号中的窄带干扰信号。
步骤 203, 将接收信号与窄带干扰预测恢复信号相减,得到消除了窄带 干扰的去窄带干扰信号;
OFDM接收装置将接收信号 ,η与预测出的窄带干扰预测恢复信号 iPEF ,n 相减, 相当于在接收信号 fcp n中去除了窄带干扰信号。 由于上述对窄带干扰 信号的预测过程基于去空子载波信号 组成的采样数据而进行, 该去空子 载波信号 Γερ η,在消除了空子载波对有效子载波的干扰的基础上, 满足近似白 噪的特征要求, 因而此时采用自适应滤波器预测出的窄带干扰信号相对而 言较为准确, 也不会出现较大的估计误差, 从而基于该窄带干扰预测信号 进行的窄带干扰消除方法也能对接收信号中的窄带干扰信号进行很好的消 除, 极大地提高了 OFDM接收装置的接收性能。
具体地, 可以对比对应于同样的信号干扰比 (Signal to Interference Ratio, 筒称 SIR ) ,在不同的接收信道中,例如在加性高斯白噪声 (Additive White Gaussion Noise, 筒称 AWGN)信道或车载 A型 (Vehicular A, 筒称 VA )信道中, 当分别采用传统的 PEF窄带干扰消除方法以及本发明实施例 的窄带干扰消除方法, 对同样的接收信号进行接收时, 所得到的窄带干扰 抵抗能力的比较仿真图。 图 4A为对应于 AGWN信道及 SIR=0dB的情况下,传统的 PEF窄带干 扰消除方法和本发明实施例的估计窄带干扰的方法的抗干扰能力仿真对比 结果示意图;图 4B为对应于 AGWN信道及 SIR=5dB的情况下,传统的 PEF 窄带干扰消除方法和本发明实施例的估计窄带干扰的方法的抗干扰能力仿 真对比结果示意图。如图 4A和图 4B所示, 当在 AWSN信道中对接收信号 进行接收时, 无论是对应于 SIR=0dB或 SIR=5dB的情况, 采用本发明实施 例的窄带干扰消除方法相比采用传统的 PEF窄带干扰消除方法, 所取得的 接收信号的干扰加噪声比 (Signal to Interference plus Noise Ratio , 筒称 SINR ) 均要明显的优于传统的 PEF窄带干扰消除方法。
图 5A为对应于 VA信道及 SIR=0dB的情况下, 传统的 PEF窄带干扰 消除方法和本发明实施例的估计窄带干扰的方法的误码率仿真对比结果示 意图; 图 5B为对应于 VA信道及 SIR=5dB的情况下, 传统的 PEF窄带干 扰消除方法和本发明实施例的估计窄带干扰的方法的误码率仿真对比结果 示意图。 同样地, 如图 5A和图 5B所示, 当在 VA信道中对接收信号进行 接收时, 无论是对应于 SIR=0dB或 SIR=5dB的情况, 采用本发明实施例的 窄带干扰消除方法相比采用传统的 PEF窄带干扰消除方法, 所取得的接收 信号的误码率也要明显的优于传统的 PEF窄带干扰消除方法。
步骤 204, 依次对去窄带干扰信号进行去循环前缀、 快速傅里叶变换、 均衡以及信号判决处理, 得到发送信号。
在对接收信号中的窄带干扰信号进行消除之后, OFDM接收装置可以 依序对去窄带干扰后的接收信号依序进行循环前缀、 FFT 变换、 均衡以及 信号判决处理, 最后得到预测的、 OFDM发送装置发送的发送信号。 预测 得到的该发送信号有效地消除了窄带干扰信号, 克服了空子载波所带来的 窄带干扰对 OFDM 系统性能的影响。 需要说明的是, 以上循环前缀、 FFT 变换、 均衡以及信号判决处理的方式可以参考现有技术, 此处不再赘述。
本实施例的估计窄带干扰的方法, 通过在 OFDM接收装置中, 在通过 误差预测滤波器对接收信号中的窄带干扰信号进行预测之前, 对接收信号 进行采样率转换处理, 且采用的采样率为空子载波数和有效子载波数的比 值, 从而可以有效地将接收信号的频谱集中在有效子载波中, 去除引入的 空子载波对接收信号的干扰, 使得误差预测滤波器对窄带干扰信号的预测 结果更加准确, 也就可以有效地解决空子载波的引入带来的窄带干扰信号 估计误差问题, 提高 OFDM接收装置的性能。
进一步地, 本实施例中通过在 OFDM接收装置中增加了去窄带干扰模 块, 基于自适应滤波器的预测方法, 对窄带干扰信号进行自适应的预测, 并将预测出的窄带干扰信号从接收信号中去除, 可以克服窄带干扰对 OFDM系统性能的影响,进一步可以提高 OFDM接收装置的信号接收性能。
本领域普通技术人员可以理解: 实现上述方法实施例的全部或部分步骤 可以通过程序指令相关的硬件来完成, 前述的程序可以存储于一计算机可读 取存储介质中, 该程序在执行时, 执行包括上述方法实施例的步骤; 而前述 的存储介质包括: ROM、 RAM, 磁碟或者光盘等各种可以存储程序代码的 介质。
图 6为本发明实施例提供的一种估计窄带干扰的装置的结构示意图, 如图 6所示, 本实施例的估计窄带干扰的装置包括采样率转换模块 11和窄 带干扰信号预测模块 12。 其中, 采样率转换模块 11用于对接收信号进行采 样率为有效子载波数与子载波总数的比值的采样率转换处理, 生成去空子 载波信号, 以将该接收信号的频谱集中在有效子载波中, 该接收信号具体 为接收到的 OFDM发送装置发送的信号;窄带干扰信号预测模块 12用于通 过误差预测滤波器对采样率转换模块 11生成的去空子载波信号进行窄带干 扰信号预测处理, 以得到接收信号的窄带干扰预测信号。
其中, 本实施例所涉及的所有功能模块、 以及其所涉及的具体工作过 在此不再赘述。 本实施例的估计窄带干扰的装置, 通过在基于误差预测滤波器对接收 信号中的窄带干扰信号进行预测之前, 对接收信号进行采样率转换处理, 且采用的采样率为空子载波数和有效子载波数的比值, 从而可以有效地将 接收信号的频谱集中在有效子载波中, 去除引入的空子载波对接收信号的 干扰, 使得误差预测滤波器对窄带干扰信号的预测结果更加准确, 也就可 以有效地解决空子载波的引入带来的窄带干扰信号估计误差问题, 提高
OFDM接收装置的性能。
图 7为本发明实施例提供的另一种估计窄带干扰的装置的结构示意图, 如图 7所示, 在上一实施例的技术方案的基础上, 本实施例的估计窄带干 扰的装置还包括采样率恢复模块 13和窄带干扰去除模块 14。 其中, 采样率 恢复模块 13用于在窄带干扰信号预测模块 12预测出窄带干扰预测信号后, 将窄带干扰预测信号进行采样率为有效子载波数和空子载波数的比值的采 样率转换处理, 生成窄带干扰预测恢复信号; 而窄带干扰去除模块 14则用 于在接收信号中减去采样率恢复模块 13生成的窄带干扰预测恢复信号, 得 到消除了窄带干扰的去窄带干扰信号。
进一步地, 本实施例中的窄带干扰信号预测模块 12还可以具体包括信 号采样子模块 121 和自适应滤波处理子模块 122。 其中, 信号采样子模块 121 用于对去空子载波信号进行采样长度为误差预测滤波器的预设长度的 连续信号采样, 得到采样数据; 自适应滤波处理子模块 122用于对信号采 样子模块 121 采样到的采样数据进行自适应滤波处理, 从采样数据中提取 出所述窄带干扰预测信号。 具体地, 该自适应滤波处理子模块 122还具体 可以用于采用自适应滤波系数遵循 LMS算法的误差预测滤波器, 对信号采 样子模块 121 采样到的采样数据进行自适应滤波处理。 即: 采用自适应滤 波系数满足更新公式为 =W* + i[ n, -iPEF,n,]RcP的误差预测滤波器, 对采样 数据进行自适应滤波处理, 以得到上述窄带干扰预测信号; 该自适应滤波 系数的更新公式中, W*为自适应滤波系数, 为调整步长, ,η,为去空子载 波信号, iPEF,n 窄带干扰预测信号, RcP为采样数据。
更进一步地,本实施例的估计窄带干扰的装置还可以包括处理模块 15, 用于在窄带干扰去除模块 14将接收信号与窄带干扰预测恢复信号相减, 得 到窄带干扰预测信号之后, 依次对该去窄带干扰信号进行去循环前缀、 快 速傅里叶变换、 均衡以及信号判决处理, 从而得到预测的 OFDM发送装置 发送的发送信号。
其中, 本实施例所涉及的所有功能模块、 以及其所涉及的具体工作过 容, 在此不再赘述。
本实施例的估计窄带干扰的装置, 通过在 OFDM接收装置中, 在通过 误差预测滤波器对接收信号中的窄带干扰信号进行预测之前, 对接收信号 进行采样率转换处理, 且采用的采样率为空子载波数和有效子载波数的比 值, 从而可以有效地将接收信号的频谱集中在有效子载波中, 去除引入的 空子载波对接收信号的干扰, 使得误差预测滤波器对窄带干扰信号的预测 结果更加准确, 也就可以有效地解决空子载波的引入带来的窄带干扰信号 估计误差问题, 提高 OFDM接收装置的性能。
进一步地, 本实施例中通过基于自适应滤波器的预测方法, 对窄带干 扰信号进行自适应的预测, 并将预测出的窄带干扰信号从接收信号中去除, 还可以克服窄带干扰对 OFDM系统性能的影响,进一步提高 OFDM接收装 置的信号接收性能。
图 8为本发明实施例提供的一种接收设备的结构示意图。 如图 8所示, 本实施例的接收设备包括: 接收模块 1以及估计窄带干扰的装置 2,估计窄 带干扰的装置 2与接收模块 1相连接, 用于对接收模块 1接收到的接收信 号进行窄带干扰信号的预测处理。 其中, 估计窄带干扰的装置 2 中所涉及 的所有功能模块、 以及其所涉及的具体工作过程, 均可以参考上述估计窄 带干扰的方法以及估计窄带干扰的装置所涉及的实施例揭露的相关内容, 在此不再赞述。 而本实施例的接收设备具体可以为 OFDM系统中的 OFDM 接收装置。
本实施例的接收设备, 应用在 OFDM接收装置中, 通过在通过误差预 测滤波器对接收信号中的窄带干扰信号进行预测之前, 对接收信号进行采 样率转换处理, 且采用的采样率为空子载波数和有效子载波数的比值, 从 而有效地将接收信号的频谱集中在了有效子载波中, 去除了引入的空子载 波对接收信号的干扰, 使得误差预测滤波器对窄带干扰信号的预测结果更 加准确, 有效地解决了空子载波的引入带来的窄带干扰信号估计误差问题, 提高了 OFDM接收装置的性能。
最后应说明的是: 以上实施例仅用以说明本发明的技术方案, 而非对 其限制; 尽管参照前述实施例对本发明进行了详细的说明, 本领域的普通 技术人员应当理解: 其依然可以对前述各实施例所记载的技术方案进行修 改, 或者对其中部分技术特征进行等同替换; 而这些修改或者替换, 并不 使相应技术方案的本质脱离本发明各实施例技术方案的精神和范围。

Claims

权利要求
1、 一种估计窄带干扰的方法, 其特征在于, 包括:
对接收信号进行采样率为有效子载波数与子载波总数的比值的采样率 转换处理, 得到去空子载波信号, 所述接收信号为接收的正交频分复用发 送装置发送的信号;
通过误差预测滤波器对所述去空子载波信号进行窄带干扰信号的预测 处理, 得到所述接收信号的窄带干扰预测信号。
2、 根据权利要求 1所述的估计窄带干扰的方法, 其特征在于, 所述得 到所述接收信号的窄带干扰预测信号之后, 所述方法还包括:
将所述窄带干扰预测信号进行采样率为所述子载波总数与所述有效子 载波数的比值的采样率转换处理, 得到窄带干扰预测恢复信号;
将所述接收信号与所述窄带干扰预测恢复信号相减, 得到消除了窄带 干扰的去窄带干扰信号。
3、 根据权利要求 1或 2所述的估计窄带干扰的方法, 其特征在于, 所 述通过误差预测滤波器对所述去空子载波信号进行窄带干扰信号的预测处 理具体包括:
对所述去空子载波信号进行连续信号采样, 得到采样数据, 其中, 所 述连续信号采样的采样长度与所述误差预测滤波器的预设长度相等;
对所述采样数据进行自适应滤波处理, 从所述采样数据中提取出所述 窄带干扰预测信号。
4、 根据权利要求 3所述的估计窄带干扰的方法, 其特征在于, 所述对 所述采样数据进行自适应滤波处理, 从所述采样数据中提取出所述窄带干 扰预测信号具体包括:
采用自适应滤波系数满足更新公式为 =W* + rcp n, -iPEF,n,]RcP的所述 误差预测滤波器, 对所述采样数据进行自适应滤波处理, 得到所述窄带干 扰预测信号; 其中, w*为自适应滤波系数, 为调整步长, ,η,为所述去空子载波信 号, iPEF,n.为所述窄带干扰预测信号, RcP为所述采样数据。
5、 根据权利要求 2所述的估计窄带干扰的方法, 其特征在于, 所述得 到消除了窄带干扰的去窄带干扰信号之后, 所述方法还包括:
依次对所述去窄带干扰信号进行去循环前缀、 快速傅里叶变换、 均衡 以及信号判决处理, 得到预测的所述正交频分复用发送装置发送的发送信
6、 一种估计窄带干扰的装置, 其特征在于, 包括:
采样率转换模块, 用于对接收信号进行采样率为有效子载波数与子载 波总数的比值的采样率转换处理, 生成去空子载波信号, 所述接收信号为 接收的正交频分复用发送装置发送的信号;
窄带干扰信号预测模块, 用于通过误差预测滤波器对所述去空子载波 信号进行窄带干扰信号的预测处理, 得到所述接收信号的窄带干扰预测信
7、 根据权利要求 6所述的估计窄带干扰的装置, 其特征在于, 所述装 置还包括:
采样率恢复模块, 用于在所述窄带干扰信号预测模块预测出所述窄带 干扰预测信号后, 将所述窄带干扰预测信号进行采样率为所述有效子载波 数和所述空子载波数的比值的采样率转换处理, 生成窄带干扰预测恢复信 窄带干扰去除模块, 用于在所述接收信号中减去所述窄带干扰预测恢 复信号, 得到消除了窄带干扰的去窄带干扰信号。
8、 根据权利要求 6或 7所述的估计窄带干扰的装置, 其特征在于, 所 述窄带干扰信号预测模块具体包括:
信号采样子模块, 用于对所述去空子载波信号进行连续信号采样, 得 到采样数据, 其中, 所述连续信号采样的采样长度与所述误差预测滤波器 的预设长度相等;
自适应滤波处理子模块, 用于对所述信号采样子模块采样到的所述采 样数据进行自适应滤波处理, 从所述采样数据中提取出所述窄带干扰预测 信号。
9、 根据权利要求 8所述的估计窄带干扰的装置, 其特征在于, 所述自 适应滤波处理子模块具体用于:
采用自适应滤波系数满足更新公式为 =W* + i[rcp n, -iPEF,n,]RcP的所述 误差预测滤波器, 对所述采样数据进行自适应滤波处理, 得到所述窄带干 扰预测信号;
其中, W*为自适应滤波系数, 为调整步长, ,η,为所述去空子载波信 号, iPEF,n.为所述窄带干扰预测信号, RcP为所述采样数据。
10、 根据权利要求 7所述的估计窄带干扰的装置, 其特征在于, 所述 装置还包括:
处理模块, 用于在所述窄带干扰去除模块将所述接收信号与所述窄带 干扰预测恢复信号相减, 得到所述窄带干扰预测信号之后, 依次对所述去 窄带干扰信号进行去循环前缀、 快速傅里叶变换、 均衡以及信号判决处理, 得到预测的所述正交频分复用发送装置发送的发送信号。
11、 一种接收设备, 包括接收模块, 其特征在于, 还包括:
如权利要求 6 ~ 10任一所述的估计窄带干扰的装置, 所述估计窄带干 扰的装置与所述接收模块连接, 用于对所述接收模块接收到的接收信号进 行窄带干扰信号的预测处理。
PCT/CN2011/081227 2010-10-25 2011-10-25 估计窄带干扰的方法、装置及接收设备 WO2012055344A1 (zh)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201010526988.7 2010-10-25
CN201010526988.7A CN101986629B (zh) 2010-10-25 2010-10-25 估计窄带干扰的方法、装置及接收设备

Publications (1)

Publication Number Publication Date
WO2012055344A1 true WO2012055344A1 (zh) 2012-05-03

Family

ID=43710933

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2011/081227 WO2012055344A1 (zh) 2010-10-25 2011-10-25 估计窄带干扰的方法、装置及接收设备

Country Status (2)

Country Link
CN (1) CN101986629B (zh)
WO (1) WO2012055344A1 (zh)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111262754A (zh) * 2020-01-16 2020-06-09 磐基技术有限公司 一种基于畸变功率去除的窄带干扰检测方法及其通信装置
CN114401526A (zh) * 2021-12-16 2022-04-26 天津七一二通信广播股份有限公司 基于双门限判决的窄带干扰位置检测方法及系统

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101986629B (zh) * 2010-10-25 2013-06-05 华为技术有限公司 估计窄带干扰的方法、装置及接收设备
CN103888158B (zh) * 2014-03-12 2016-08-24 深圳市道通科技股份有限公司 带滤波的低频载波接收装置及方法
CN104502925A (zh) * 2015-01-22 2015-04-08 西安航天华迅科技有限公司 一种基于自适应信号处理的抗窄带干扰系统及方法
FR3034274B1 (fr) * 2015-03-27 2017-03-24 Stmicroelectronics Rousset Procede de traitement d'un signal analogique issu d'un canal de transmission, en particulier un signal vehicule par courant porteur en ligne
CN111552019B (zh) * 2020-05-29 2022-07-19 无锡奥夫特光学技术有限公司 一种具有高质量面形偏差的窄带滤波片

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1578292A (zh) * 2003-07-08 2005-02-09 三星电子株式会社 正交频分复用系统中的发送和接收设备及方法
CN101652946A (zh) * 2007-03-29 2010-02-17 松下电器产业株式会社 正交频分复用接收装置及正交频分复用接收方法
CN101986629A (zh) * 2010-10-25 2011-03-16 华为技术有限公司 估计窄带干扰的方法、装置及接收设备

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3905695A1 (de) * 1989-02-24 1990-08-30 Siemens Ag Digitaluebertragungssystem
CN1820306B (zh) * 2003-05-01 2010-05-05 诺基亚有限公司 可变比特率宽带语音编码中增益量化的方法和装置

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1578292A (zh) * 2003-07-08 2005-02-09 三星电子株式会社 正交频分复用系统中的发送和接收设备及方法
CN101652946A (zh) * 2007-03-29 2010-02-17 松下电器产业株式会社 正交频分复用接收装置及正交频分复用接收方法
CN101986629A (zh) * 2010-10-25 2011-03-16 华为技术有限公司 估计窄带干扰的方法、装置及接收设备

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
YANG ZAN ET AL.: "Narrowband Interference Suppression for OFDM Systems with Guard Band.", IEEE VEHICULAR TECHNOLOGY CONFERENCE FALL, 4 October 2010 (2010-10-04), pages 1 - 5 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111262754A (zh) * 2020-01-16 2020-06-09 磐基技术有限公司 一种基于畸变功率去除的窄带干扰检测方法及其通信装置
CN114401526A (zh) * 2021-12-16 2022-04-26 天津七一二通信广播股份有限公司 基于双门限判决的窄带干扰位置检测方法及系统

Also Published As

Publication number Publication date
CN101986629B (zh) 2013-06-05
CN101986629A (zh) 2011-03-16

Similar Documents

Publication Publication Date Title
Zhang et al. Mixed numerologies interference analysis and inter-numerology interference cancellation for windowed OFDM systems
WO2012055344A1 (zh) 估计窄带干扰的方法、装置及接收设备
EP2404385B1 (en) Dsl noise cancellation
JP5302887B2 (ja) キャリア間干渉を相殺する伝送方法及び伝送装置
Al‐Jawhar et al. Improving PAPR performance of filtered OFDM for 5G communications using PTS
Yucek et al. Carrier frequency offset compensation with successive cancellation in uplink OFDMA systems
US8428163B2 (en) Method and system for Doppler spread and delay spread matching with channel estimation by circular convolution in OFDM communication networks
EP2928140B1 (en) Method and a device for cancelling a narrow band interference in a single carrier signal
JP2007195218A (ja) デジタル無線周波数干渉打消器
WO2009089753A1 (fr) Procédé et dispositif pour l'élimination du rapport valeur de crête sur valeur moyenne dans un système de multiplexage par répartition orthogonale de la fréquence multiporteuses
KR101313862B1 (ko) Mimo 수신기에 사용되는 간섭 제거기, mimo 수신기에서 간섭을 제거하는 방법 및 mimo 수신기
US20150229358A1 (en) Power line communication transceiver and power line communication method
US11070415B2 (en) Overlap-save FBMC receiver
US20110026618A1 (en) Method and system for low complexity channel estimation in ofdm communication networks using circular convolution
Zhang et al. OFDM scheme based on complex orthogonal wavelet packet
US7236534B1 (en) Method and apparatus for noise reduction by spectral and subcarrier averaging
US9106497B2 (en) Apparatus and method for improving OFDM receiver performance in the presence of narrowband interferers
US20170155498A1 (en) Apparatuses and methodologies for blind equalization in a communication system
Yu et al. Reducing out-of-band radiation of OFDM-based cognitive radios
Rugini et al. Block DFE and windowing for Doppler-affected OFDM systems
JP4675790B2 (ja) 通信装置および通信システム
JP2012175283A (ja) Ofdm信号受信装置および中継装置
Pande et al. A method for narrowband interference mitigation in OFDM by minimizing spectral leakage
JP5143533B2 (ja) 受信装置、及び信号処理方法
Seifert et al. Soft-PIC frequency-domain equalization in iterative MIMO receivers for the LTE-A uplink

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 11835617

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 11835617

Country of ref document: EP

Kind code of ref document: A1