WO2017206320A1 - 使用时频分析测量的单道天线远场天线因子估计方法 - Google Patents

使用时频分析测量的单道天线远场天线因子估计方法 Download PDF

Info

Publication number
WO2017206320A1
WO2017206320A1 PCT/CN2016/093510 CN2016093510W WO2017206320A1 WO 2017206320 A1 WO2017206320 A1 WO 2017206320A1 CN 2016093510 W CN2016093510 W CN 2016093510W WO 2017206320 A1 WO2017206320 A1 WO 2017206320A1
Authority
WO
WIPO (PCT)
Prior art keywords
antenna
distance
far
time
ground
Prior art date
Application number
PCT/CN2016/093510
Other languages
English (en)
French (fr)
Inventor
张丛
Original Assignee
深圳市樊溪电子有限公司
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 深圳市樊溪电子有限公司 filed Critical 深圳市樊溪电子有限公司
Publication of WO2017206320A1 publication Critical patent/WO2017206320A1/zh

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R29/00—Arrangements for measuring or indicating electric quantities not covered by groups G01R19/00 - G01R27/00
    • G01R29/08—Measuring electromagnetic field characteristics
    • G01R29/10—Radiation diagrams of antennas

Definitions

  • the present invention relates to a method of antenna factor estimation, and more particularly to a factor estimation method for a single-channel far-field antenna measured using a time-frequency method.
  • the current far-field antenna factor measurement method has the following drawbacks.
  • the time-domain subtraction method cannot be used to separate the ground reflected wave from the inherent self-reflected wave of the antenna to be tested.
  • the previously proposed measurement method uses a fixed antenna. Therefore, the main measurement uncertainty of the far-field antenna factor estimation is mostly related to the distance of the antenna, so the uncertainty of the measurement cannot be reduced.
  • the antenna distance at each frequency cannot be determined, so that it cannot be effectively
  • the estimation method is determined to estimate the far-field antenna factor.
  • the time domain analysis method and the time-frequency analysis method cannot be effectively utilized, and the short-time Fourier transform technique is used to determine the antenna factor, so that the estimation accuracy is not high.
  • a single-channel antenna far-field antenna parameter estimation method using time-frequency analysis measurement is proposed.
  • the method is applied to a log-periodic dipole array antenna with a spacing of 10 meters between the antennas.
  • This method uses a time-frequency analysis method. Effectively suppressing some of the undesired reflections occurring in the single antenna method, and estimating the far-field antenna factor using the antenna distance estimated by the time-frequency method.
  • using the antenna radiation center distance correction consensus to estimate the distance of the dipole array antenna for several weeks
  • the field antenna factor compared to the far-field antenna factor estimated by other methods, the estimated antenna factor has better far-field gain compatibility.
  • the antenna distance is 5 meters, and the frequency range is from 300 MHz to 1000.
  • the frequency difference in the range of megahertz is less than 0.3 dB.
  • s 11 (t) includes s 11intrinsic (t), s 11ground_ref (t) and other undesired waveforms
  • s 11intrinsic (t) is the intrinsic reflection of the internal structure of the antenna
  • s 11ground_ref (t) is the normal incidence reflection of the ground Reflected waves
  • other undesired reflected waveforms have undesired ambient reflected waves, such as radomes;
  • the direct reflection wave s 11ground_ref (t) can be obtained by subtracting s 11intrinsic (t) from the time domain s 11 (t) by the formula (2).
  • the formula (2) is as follows:
  • ⁇ 0 is the corresponding free-space wavelength
  • D( ⁇ ) is the two-way of the object to be measured from the radiation point to the ground.
  • Distance in the case where the logarithmic period dipole array antenna is the measurement object, the formula of the bidirectional distance is as shown in formula (4):
  • z is the bidirectional distance from the top of the object to be tested to the ground, and d 1-f is the distance from the top of the antenna to the radiation point of the dipole array antenna of the logarithmic period;
  • FIG. 1 is a schematic diagram of establishing an antenna factor measurement value using an antenna sub-calibration method according to an embodiment of the present invention
  • FIG. 2 is a schematic diagram showing calibration results of a logarithmic period dipole array antenna s 11 (t) according to an embodiment of the present invention
  • FIG. 3 is a schematic diagram of an estimated value of s 11_ground_ref (t) of a log periodic dipole array antenna according to an embodiment of the present invention
  • FIG. 4 is a diagram showing the difference values between the far-field antenna factor estimated by the method of the embodiment of the present invention and the antenna factor estimated using other methods.
  • a single-channel antenna far-field antenna factor estimation method using time-frequency analysis measurement firstly, the method is used for calibrating a log-period dipole array antenna, and an experimental establishment method thereof is schematically shown in FIG. 1 . All measurements are made on the ground in the anechoic chamber. The logarithmic period dipole antenna array is used as the object to be measured. The antenna is perpendicular to the ground and is located between the ground and the distance between 1 m and 5 m.
  • the reflection coefficient s 11 ( ⁇ ) of the frequency domain is measured by a vector network analyzer and converted into a corresponding time domain reflection coefficient s 11 (t); s 11 (t) is calculated by the formula (1), wherein the formula uses Fourier The inverse transform F -1 ( ⁇ ) and the Hanning frequency domain window W( ⁇ ), the formula (1) is as follows:
  • s 11 (t) includes s 11intrinsic (t), s 11ground_ref (t) and other undesired waveforms
  • s 11intrinsic (t) is the intrinsic reflection of the internal structure of the antenna
  • s 11ground_ref (t) is the normal incidence reflection of the ground Reflected waves
  • other undesired reflected waveforms have undesired ambient reflected waves, such as radomes, and the estimated time domain waveforms are shown in Figure 2.
  • we In order to estimate the free-space antenna factor, we must pick up the reflected waves incident on the vertical ground. First, we estimate s 11intrinsic (t) by averaging s 11 (t), because the phase of s 11intrinsic (t)) does not change.
  • the direct reflected wave s 11ground_ref (t) can be obtained by subtracting s 11intrinsic (t) from the time domain s 11 (t) by the formula (2).
  • the formula (2) is as follows:
  • the number of Fourier transforms is 8196; the antenna factor is estimated from the estimated antenna distance using equation (3), where equation (3) is as follows:
  • ⁇ 0 is the corresponding free-space wavelength
  • D( ⁇ ) is the two-way of the object to be measured from the radiation point to the ground.
  • Distance in the case where the logarithmic period dipole array antenna is the measurement object, the formula of the bidirectional distance is as shown in formula (4):
  • z is the bidirectional distance from the top of the object to be tested to the ground, and d 1-f is the distance from the top of the antenna to the radiation point of the dipole array antenna of the logarithmic period;
  • Figure 4 shows the difference between the far-field antenna factors estimated using the antenna factor estimated by the method of the present invention and the corresponding other methods.
  • the three measurement cases are fixed length, short time Fourier transform, and short time Fourier transform - unit length.
  • the frequency difference is less than 0.3 dB in the range of the frequency range from 300 megahertz to 1000 megahertz at an antenna distance of 5 m.

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • General Physics & Mathematics (AREA)
  • Radar Systems Or Details Thereof (AREA)
  • Geophysics And Detection Of Objects (AREA)
  • Variable-Direction Aerials And Aerial Arrays (AREA)

Abstract

本发明提出一种使用时频分析测量的单通道天线远场天线参数估计方法，该方法应用于对数周期偶极数组天线，天线之间的间距为10米，该方法应用时间频率分析方法从而有效抑制一些该单一天线方法中出现的非期望反射，并且利用由时间频率方法所估计的天线距离估计远场天线因子，另外，使用天线辐射中心距离修正共识来估计对数周其偶极数组天线的远场天线因子，与其他方法所估计的远场天线因子相比，所估计的天线因子具有更好的远场增益相容性，天线距离为5米的地方，在频率范围从300兆赫兹到1000兆赫兹的范围内频率差异低于0.3dB。

Description

使用时频分析测量的单道天线远场天线因子估计方法 技术领域
本发明涉及一种天线因子估计的方法，特别是采用时间-频率方法测量的针对单道远场天线的因子估计方法。
背景技术
目前的远场天线因子测量方法存在如下的缺陷，首先不能使用时间域的减法将地面反射波和待测天线的固有自反射波分开测量；另外，之前所提出的测量方法是用固定的天线具有，由此，远场天线因子估计的主要的测量不确定度大部分和天线的距离有关，因此不能降低测量的不确定度；第三，不能确定每个频率下的天线距离，从而不能有效地确定估计方法来估计远场天线因子；第四，不能有效利用时域分析方法和时频分析方法，并使用其中的短时傅立叶变换技术进行天线因子的确定，从而估计精度不高。
由此提出一种使用时频分析测量的单通道天线远场天线参数估计方法，该方法应用于对数周期偶极数组天线，天线之间的间距为10米，该方法应用时间频率分析方法从而有效抑制一些该单一天线方法中出现的非期望反射，并且利用由时间频率方法所估计的天线距离估计远场天线因子，另外，使用天线辐射中心距离修正共识来估计对数周其偶极数组天线的远场天线因子，与其他方法所估计的远场天线因子相比，所估计的天线因子具有更好的远场增益相容性，天线距离为5米的地方，在频率范围从300兆赫兹到1000兆赫兹的范围内频率差异低于0.3dB。
发明内容
本发明的目的通过如下方案实现：
一种使用时频分析测量的单通道天线远场天线因子估计方法，该方法用于标定对数周期偶极数组天线，包括如下步骤：
(1)在消声室内的地面上设置所有的测量对象，将对数周期偶极距天线阵列作为被测对象，天线垂直于地面并位于地面之上的间距为1米到5米之间的范围；
(2)通过矢量网络分析仪测量频域的反射系数s11(ω)，并且将其转换为相应的时域反射系数s11(t)；
(3)通过公式(1)计算s11(t)，其中公式使用傅立叶逆变换F-1(ω)以及汉宁频域窗 W(ω)，其中公式(1)为：
s11(t)＝F-1(W(ω)s11(ω))       (1)
其中s11(t)包括s11intrinsic(t),s11ground_ref(t)以及其他非期望的波形，其中s11intrinsic(t)为天线内部结构的固有反射，s11ground_ref(t)为地面的垂直入射反射反射波，其他非期望反射波形具有非期望的环境反射波，如天线罩等；
(4)拾取垂直地面入射的反射波从而估计自由空间天线因子，采用将s11(t)平均的方式估计s11intrinsic(t)，随着垂直对天线进行扫描将s11(t)平均，保留不变的部分s11intrinsic(t)，并将其从s11(t)提取出；
(5)通过公式(2)将s11intrinsic(t)从时域的s11(t)中减去可以得到直接反射波s11ground_ref(t)，公式(2)如下：
s11ground_ref(t)＝s11(t)-s11intrinsic(t)           (2)；
(6)使用短时傅立叶变换以及汉宁时间窗的方法计算s11ground_ref(t)的时间-频率响应，从而确定每个频率的天线距离D＝z(ω)，其中，汉宁窗时域宽度为20ns，傅立叶变换的次数为8196；
(7)使用公式(3)由估计的天线距离估计天线因子：
af2(ω,z)＝η0·[Z0·λ0·D(ω)·s11ground_ref(ω,z)]-1            (3)
其中，η0＝120πΩ为自由空间特征阻抗，Z0＝50Ω为同轴线缆的特征阻抗，并且λ0为相应的自由空间波长，D(ω)为待测对象幅射点到地面的双向距离，在对数周期偶极数组天线为测量对象的情况下，该双向距离的公式如公式(4)所示：
D(ω)＝z+2×d1-f-λ           (4)
其中，z为从待测对象的顶部到地面的双向距离，d1-f为天线顶部到对数周期偶极数组天线辐射点的距离；
(8)将天线的幅值中心位置应用于公式(4)获得远场天线因子估计值的公式(5)：
Figure PCTCN2016093510-appb-000001
其中，affar(ω)为远场天线因子。
附图说明
附图1为根据本发明实施例使用天线子标定方法建立天线因子测量值的示意图；
附图2为根据本发明实施例的对数周期偶极数组天线s11(t)的标定结果示意图；
附图3为根据本发明实施例的对数周期偶极数组天线的s11_ground_ref(t)估计值示意图；
附图4为采用本发明实施例方法估计的远场天线因子与使用其它方法估计的天线因子之间的差异值示意图。
附图标记：1-待测天线 2-地面 3-网络分析仪
具体实施方式
一种使用时频分析测量的单通道天线远场天线因子估计方法，首先该方法用于标定对数周期偶极数组天线，其实验建立方法示意性的如图1所示。所有的测量都是建立在消声室内的地面上，将对数周期偶极距天线阵列作为被测对象，天线垂直于地面并位于地面之上的间距为1米到5米之间的范围；通过矢量网络分析仪测量频域的反射系数s11(ω)，并且将其转换为相应的时域反射系数s11(t)；通过公式(1)计算s11(t)，其中公式使用傅立叶逆变换F-1(ω)以及汉宁频域窗W(ω)，公式(1)如下所示：
s11(t)＝F-1(W(ω)s11(ω))         (1)
其中s11(t)包括s11intrinsic(t),s11ground_ref(t)以及其他非期望的波形，其中s11intrinsic(t)为天线内部结构的固有反射，s11ground_ref(t)为地面的垂直入射反射反射波，其他非期望反射波形具有非期望的环境反射波，如天线罩等，所估计的时域波形如图2所示。为了估计自由空间天线因子，我们必须拾取垂直地面入射的反射波，首先采用将s11(t)平均的方式估计s11intrinsic(t)，这是因为s11intrinsic(t))的相位不会变化，即使距离地面的位置高度变化了，而相反的是，随着相对地面的双向传播，s11ground_ref(t)的相位会发生变化，随着垂直对天线进行扫描将s11(t)平均，保留不变的部分s11intrinsic(t)，并将其从s11(t)提取出，也就是说， 在时间轴上以固定的延迟时间出现不变的s11intrinsic(t)。
通过公式(2)将s11intrinsic(t)从时域的s11(t)中减去可以得到直接反射波s11ground_ref(t)，公式(2)如下所示：
s11ground_ref(t)＝s11(t)-s11intrinsic(t)          (2)；
所估计的s11ground_ref(t)如图3所示。
使用短时傅立叶变换以及汉宁时间窗的方法计算s11ground_ref(t)的时间-频率响应，从而确定每个频率的天线距离D＝z(ω)，其中，汉宁窗时域宽度为20ns，傅立叶变换的次数为8196；使用公式(3)由估计的天线距离估计天线因子，其中公式(3)如下所示：
af2(ω,z)＝η0·[Z0·λ0·D(ω)·s11ground_ref(ω,z)]-1           (3)
其中，η0＝120πΩ为自由空间特征阻抗，Z0＝50Ω为同轴线缆的特征阻抗，并且λ0为相应的自由空间波长，D(ω)为待测对象幅射点到地面的双向距离，在对数周期偶极数组天线为测量对象的情况下，该双向距离的公式如公式(4)所示：
D(ω)＝z+2×d1-f-λ          (4)
其中，z为从待测对象的顶部到地面的双向距离，d1-f为天线顶部到对数周期偶极数组天线辐射点的距离；
将天线的幅值中心位置应用于公式(4)获得远场天线因子估计值的计算公式(5)：
Figure PCTCN2016093510-appb-000002
其中，affar(ω)为远场天线因子。
附图4表示使用本发明所述方法所估计的天线因子和相应的其他方法估计的远场天线因子之间的差值。三种测量情况分别是固定长度，短时傅立叶变换，以及短时傅立叶变换-单元长度。结果发现，采用本发明的方法，天线距离为5米的地方，在频率范围从300兆赫兹到1000兆赫兹的范围内频率差异低于0.3dB。

Claims (1)

  1. 使用时频分析测量的单通道天线远场天线因子估计方法，该方法用于标定对数周期偶极数组天线，其特征在于包括如下步骤：
    (1)在消声室内的地面上设置所有的测量对象，将对数周期偶极距天线阵列作为被测对象，天线垂直于地面并位于地面之上的间距为1米到5米之间的范围；
    (2)通过矢量网络分析仪测量频域的反射系数s11(ω)，并且将其转换为相应的时域反射系数s11(t)；
    (3)通过公式(1)计算s11(t)，其中公式使用傅立叶逆变换F-1(ω)以及汉宁频域窗W(ω)，其中公式(1)为：
    s11(t)＝F-1(W(ω)s11(ω))   (1)
    其中s11(t)包括s11intrinsic(t),s11ground_ref(t)以及其他非期望的波形，其中s11intrinsic(t)为天线内部结构的固有反射，s11ground_ref(t)为地面的垂直入射反射反射波，其他非期望反射波形具有非期望的环境反射波，如天线罩等；
    (4)拾取垂直地面入射的反射波从而估计自由空间天线因子，采用将s11(t)平均的方式估计s11intrinsic(t)；(因为s11intrinsic(t))的相位不会变化，即使距离地面的位置高度变化了，而相反的是，随着相对地面的双向传播，s11ground_ref(t)的相位会发生变化)，随着垂直对天线进行扫描将s11(t)平均，保留不变的部分s11intrinsic(t)，并将其从s11(t)提取出；(也就是说，在时间轴上以固定的延迟时间出现不变的s11intrinsic(t))；
    (5)通过公式(2)将s11intrinsic(t)从时域的s11(t)中减去可以得到直接反射波s11ground_ref(t)，公式(2)如下：
    s11ground_ref(t)＝s11(t)-s11intrinsic(t)   (2)；
    (6)使用短时傅立叶变换以及汉宁时间窗的方法计算s11ground_ref(t)的时间-频率响应，从而确定每个频率的天线距离D＝z(ω)，其中，汉宁窗时域宽度为20ns，傅立叶变换的次数为8196；
    (7)使用公式(3)由估计的天线距离估计天线因子：
    af2(ω,z)＝η0·[Z0·λ0·D(ω)·s11ground_ref(ω,z)]-1   (3)
    其中，η0＝120πΩ为自由空间特征阻抗，Z0＝50Ω为同轴线缆的特征阻抗，并且λ0为相应的自由空间波长，D(ω)为待测对象幅射点到地面的双向距离，在对数周期偶极数组天线为测量对象的情况下，该双向距离的公式如公式(4)所示：
    D(ω)＝z+2×d1-f-λ   (4)
    其中，z为从待测对象的顶部到地面的双向距离，d1-f为天线顶部到对数周期偶极数组天线辐射点的距离；
    (8)将天线的幅值中心位置应用于公式(4)获得远场天线因子估计值的公式(5)：
    Figure PCTCN2016093510-appb-100001
    其中，affar(ω)为远场天线因子。
PCT/CN2016/093510 2016-06-03 2016-08-05 使用时频分析测量的单道天线远场天线因子估计方法 WO2017206320A1 (zh)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201610388610.2 2016-06-03
CN201610388610.2A CN106053968B (zh) 2016-06-03 2016-06-03 使用时频分析测量的单道天线远场天线因子估计方法

Publications (1)

Publication Number Publication Date
WO2017206320A1 true WO2017206320A1 (zh) 2017-12-07

Family

ID=57170269

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2016/093510 WO2017206320A1 (zh) 2016-06-03 2016-08-05 使用时频分析测量的单道天线远场天线因子估计方法

Country Status (2)

Country Link
CN (1) CN106053968B (zh)
WO (1) WO2017206320A1 (zh)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112595902B (zh) * 2020-12-24 2022-07-15 中国科学技术大学 一种阵列天线系统故障诊断方法及装置

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2003062840A1 (en) * 2002-01-18 2003-07-31 Her Majesty In Right Of Canada As Represented By The Minister Of Industry Antenna array for the measurement of complex electromagnetic fields
CN101308177A (zh) * 2008-07-11 2008-11-19 西安电子科技大学 主动反射面天线的电性能预测方法
CN102818942A (zh) * 2012-08-24 2012-12-12 湖北航天技术研究院计量测试技术研究所 天线远场参数校准装置及校准方法

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5204685A (en) * 1992-07-01 1993-04-20 The United States Of America As Represented By The Secretary Of The Air Force ARC range test facility
JP2004354362A (ja) * 2003-05-29 2004-12-16 Taiyo Musen Co Ltd アンテナの遠方界放射パターン測定法
CN1744379A (zh) * 2005-09-28 2006-03-08 中山大学 多端口控制频率固定波束可调的微带漏波天线
CN103245841B (zh) * 2013-04-28 2015-07-01 西北工业大学 一种基于球面近场扫描外推的天线方向图测试方法
CN104931799B (zh) * 2015-04-30 2018-02-06 中国电子科技集团公司第四十一研究所 一种在片天线的电性能测试系统及方法
CN105445566A (zh) * 2015-11-13 2016-03-30 西北工业大学 球面多探头天线测试数据处理方法

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2003062840A1 (en) * 2002-01-18 2003-07-31 Her Majesty In Right Of Canada As Represented By The Minister Of Industry Antenna array for the measurement of complex electromagnetic fields
CN101308177A (zh) * 2008-07-11 2008-11-19 西安电子科技大学 主动反射面天线的电性能预测方法
CN102818942A (zh) * 2012-08-24 2012-12-12 湖北航天技术研究院计量测试技术研究所 天线远场参数校准装置及校准方法

Also Published As

Publication number Publication date
CN106053968A (zh) 2016-10-26
CN106053968B (zh) 2019-09-10

Similar Documents

Publication Publication Date Title
Barowski et al. A compact measurement setup for in-situ material characterization in the lower THz range
Jarvis et al. Measurement and signal processing techniques for extracting highly accurate and wideband RCS
Barowski et al. Millimeter wave material characterization using FMCW-transceivers
WO2017206320A1 (zh) 使用时频分析测量的单道天线远场天线因子估计方法
Chen et al. Examination of Antenna Calibration Methodologies in an Extrapolation Range
Kurokawa et al. Antenna gain and phase center estimation for broadband antenna using metal ground plane
Foged et al. Facility comparison and evaluation using dual ridge horns
Anchidin et al. Near-field gain measurements: Single-probe distance averaging in a multipath site versus multi-probe field scanning inside an anechoic chamber
Sun et al. Time delay and interface roughness estimations by GPR for pavement survey
RU2572843C1 (ru) Способ улучшения характеристик измерения азимута наземных целей с учетом отражений от подстилающей поверхности
Anchidin et al. Near-field gain measurements using the distance averaging method: linear scanning versus matrix scanning
Zeitler et al. Amplitude and phase measurements of scattered fields for quantitative imaging in the W-band
Harima et al. Determination of gain for pyramidal-horn antenna on basis of phase center location
Ala-Laurinaho et al. Reflection coefficient method for antenna radiation pattern measurements
Tamas et al. An indoor measuring technique for antenna gain
Kurokawa et al. Far field antenna factor estimation for a single antenna measurement using time frequency analysis
Deacu et al. On the accuracy of the distance-averaging method for antenna gain measurements
Yoshihara et al. Free-space factor calibration of hybrid antenna
JP3451324B2 (ja) 平面走査近傍界アンテナ測定の適用範囲判定法
CN116559745B (zh) 一种平面近场法天线测量中的扫描探头修正方法
Wang et al. Comparison of EMC Chamber Debugging Techiniques above 1GHz
Roussafi et al. UWB antenna 3D characterization using matrix pencil method
Akhdar et al. A simple technique for angle of arrival measurement
Mertens et al. Determination of the stability of a pulse GPR system and quantification of the drift effect on soil material characterization by full-wave inversion
AMEYA et al. Antenna gain self-calibration method with moving flat reflector for millimeter-wave frequency band

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: 16903702

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: 16903702

Country of ref document: EP

Kind code of ref document: A1