According to the characteristics of the high precise gps deformation monitoring , basing on the first period observation results of the monitoring network , the similar single - difference model of solving gps monitor point deformation information at single epoch is built , and the receivers ' antenna phase center offsets are discussed 摘要根据高精度gps变形监测的特点，以监测网的首期观测成果为基础，建立了单历元解算监测点变形量的似单差模型，讨论了接收机天线相位中心偏差的改正方法。
In addition to the conventional techniques such as low sidelobe antennas and displaced phased center antenna ( dpca ) , there has been great interest in space - time adaptive processing ( stap ) because it can suppress clutter effectively and improve the detection performance of airborne phased array radar evidently 除了采用低副瓣天线、偏置天线相位中心( dpca )等传统杂波抑制技术，能够有效提高机载相控阵雷达地杂波抑制能力和动目标检测性能的空时二维自适应处理( stap )受到了广泛关注。
The paper overviews the history of moving targets detection and imaging based on sar , the methods based on doppler filtering , doppler rate filtering , parameter estimation and multichannel sar imaging are discussed in detail . the paper focuses on the two methods used in spaceborne sar which are displaced phase center antenna and along - track interferometric 论文回顾了合成孔径雷达检测与成像运动目标的发展历史，详细地论述了基于多普勒滤波、基于多普勒速率滤波、基于参数估计以及基于多通道sar的运动目标检测与成像方法。
As a result , the ultra - wideband antenna must be able to radiate and receive the short pulse signals without distortion , in other words , the ultra - wideband antenna has to own several octave impedance bandwidth or more , and stable phase center , which enables the ultra - wideband antenna to transmit and receive short pulse signals without distortion 这就要求超宽带天线具有辐射和接收时域短脉冲信号的能力,即拥有几个甚至十几个倍频程的阻抗带宽,同时天线应具有稳定的相位中心以保证不失真地收发短脉冲信号。
3 . after studying deeply the multi - antenna sar mtdi based on displaced phase center antenna ( dpca ) , a new double - antenna method is proposed which remedies the shortcomings of conventional ways . the method need n ' t meet the constraint condition that conventional ways must meet and can suppress ground clutter effectively and detect moving target 针对常规dpca方法的缺点创新性的提出了一种新的双天线动目标检测方法，建立了该方法的检测模型并对该方法进行了有效的验证，该方法不合成孔什雷达动口标检测和成像研必满足常规方法所必须满足的限制条件就能够进行动目标检测，提高了dpca的实用价值。
Firstly , the differences between the ultra - wideband antenna and conventional wideband antenna are introduced in this thesis , and the definitions of several performance parameters of the ultra - wideband antenna are presented , among which the phase center and the group delay time are primarily discussed in that they describe the time domain properties of the antenna 首先,简要介绍了超宽带天线与传统超宽带天线的区别,给出了超宽带天线的性能参数在时域的描述方法。着重介绍了描述超宽带天线时域特性的两个参数,即相位中心和群延时。
In field gps work , errors of receiver ' s antenna phase center and instrument height measurement are inevitable , so in this paper the influence of the error of instrument height measurement on planar coordinates is studied and it is proved theoretically that the influence of the error of instrument height measurement on planar coordinates can be neglected ; 3 在gps实际作业中，接收机天线相位中心偏差和仪器高的量测误差都是不可避免的。基于此原因，本文研究了仪器高量测误差对平面坐标的影响，并从理论上证明了仪器高量测误差对平面坐标的影响可忽略不计； 3
In this paper , the variable phase center is calculated in the full space for the first time . the condition under which a linear array has a variable phase center in the full space is derived in the paper . it is concluded that the non - similar array has not variable phase center in the full space , but it has variable phase center in the e - plane and h - plane independently 本文首次将相位中心扩展到全空间中进行计算,导出了直线阵列在全空间中存在可变相位中心的条件,得出了由非相似单元组成的线阵列在全空间并非处处存在可变相位中心,但在e面和h面独立存在各自的可变相位中心这一重要结论。
This dissertation mainly researches the displaced phase center antenna ( dpca ) technique in the new system , and the contributions are calculated as following : 1 . the doppler history is analyzed for the spaceborne bistatic sar , doppler center frequency and doppler fm rate computational methods are studied . summing up is done for the methods of moving target detection and imaging 本文完成的主要工作有: 1 .分析慢速运动目标信号特征以及运动目标对sar成像的影响(多普勒中心频率,多普勒斜率以及距离徙动误差) ,总结了目前sar运动目标检测与成像的主要方法。
The circular monopole ultra - wideband antenna has not only the extremely wide band in frequency domain , but also stable phase center , which makes the antenna radiate and receive the short pulse signals without any distortion , and suitable for various ultra - wideband communication systems or the single antenna of other multi - frequency operating communication systems 这种天线不仅具有极宽的阻抗带宽,还拥有稳定的相位中心。这使得圆盘单极超宽带天线可以不失真地收发时域短脉冲信号。所以该天线不仅适用于超宽带通信中,还能够作为复杂多频工作系统的单一收发天线。
