Based on the fabricated 12-element cavity-backed microstrip sector cylinder array,a novel hybrid alternate projection algorithm（HAPA）,which combines analytical method with numerical techniques effectively,is propose...Based on the fabricated 12-element cavity-backed microstrip sector cylinder array,a novel hybrid alternate projection algorithm（HAPA）,which combines analytical method with numerical techniques effectively,is proposed for synthesizing the pattern of practical conformal array.The algorithm applies the variable direction aperture projection method with mutual coupling correction techniques to provide the good initial excitations of elements to the enhanced alternate projection algorithm（EAPA）.In order to do further optimization,which improves the convergent speed of the algorithm significantly.Finally,the HAPA has been applied to the fabricated sector cylinder array with mutual coupling considered.The results of synthesized patterns,such as low sidelobe with null points formed pattern,beam scanning with low sidelobe pattern and the shaped beam pattern are presented.It demonstrates the validity of HAPA in practical conformal array synthesis.展开更多
MUSIC(Multiple Signal Classification)算法是波达角(the Direction of Arrival,DOA)估计的经典算法之一,但其在二维DOA估计中因需进行二维谱峰搜索而计算量十分巨大.为降低MUSIC算法的计算量,本文在引入变换域DOA概念的基础上提出了...MUSIC(Multiple Signal Classification)算法是波达角(the Direction of Arrival,DOA)估计的经典算法之一,但其在二维DOA估计中因需进行二维谱峰搜索而计算量十分巨大.为降低MUSIC算法的计算量,本文在引入变换域DOA概念的基础上提出了一种能够适用于任意阵列结构的二维DOA快速估计算法,即变换域MUSIC(transformed do-main-MUSIC,TD-MUSIC)算法.理论分析和仿真实验表明:该算法不但将空间谱峰搜索的范围减小一半而且具有更低维度的噪声子空间,因而其计算量远小于MUSIC算法.同时,新算法具有比MUSIC更高的空间分辨率.展开更多
Finding the intersection of two subspaces is of great interest in many fields of signal processing. Over several decades,there have been numerous formulas discovered to solve this problem, among which the alternate pr...Finding the intersection of two subspaces is of great interest in many fields of signal processing. Over several decades,there have been numerous formulas discovered to solve this problem, among which the alternate projection method(APM) is the most popular one. However, APM suffers from high computational complexity, especially for real-time applications. Moreover, APM only gives the projection instead of the orthogonal basis of two given subspaces. This paper presents two alternate algorithms which have a closed form and reduced complexity as compared to the APM technique. Numerical simulations are conducted to verify the correctness and the effectiveness of the proposed methods.展开更多
基于交替方向乘子法(alternating direction method of multipliers,ADMM)的线性规划(liner programming,LP)译码模型因其不会出现错误平台和具有最大似然认证的优点,广受译码研究者的关注。目前大多数ADMM算法采用的是泛洪调度策略(flo...基于交替方向乘子法(alternating direction method of multipliers,ADMM)的线性规划(liner programming,LP)译码模型因其不会出现错误平台和具有最大似然认证的优点,广受译码研究者的关注。目前大多数ADMM算法采用的是泛洪调度策略(flooding,FL),该算法存在译码收敛速度过慢的问题。基于水平分层调度的交替方向乘子法的低密度奇偶校验(low density parity check,LDPC)码译码算法能够加速译码收敛速度,然而目前水平分层调度算法中的投影算法采用的为精确投影算法,复杂度较高。针对该问题,将近似投影算法和水平分层调度算法结合,提出基于近似投影的ADMM水平分层调度译码算法以提高译码的性能。仿真实验表明,相比其他算法,本文提出的算法的译码性能可提升0.1~0.3 dB,迭代次数可降低19%~40%,平均译码时间可减少21%~65%。展开更多
文摘Based on the fabricated 12-element cavity-backed microstrip sector cylinder array,a novel hybrid alternate projection algorithm（HAPA）,which combines analytical method with numerical techniques effectively,is proposed for synthesizing the pattern of practical conformal array.The algorithm applies the variable direction aperture projection method with mutual coupling correction techniques to provide the good initial excitations of elements to the enhanced alternate projection algorithm（EAPA）.In order to do further optimization,which improves the convergent speed of the algorithm significantly.Finally,the HAPA has been applied to the fabricated sector cylinder array with mutual coupling considered.The results of synthesized patterns,such as low sidelobe with null points formed pattern,beam scanning with low sidelobe pattern and the shaped beam pattern are presented.It demonstrates the validity of HAPA in practical conformal array synthesis.
文摘MUSIC(Multiple Signal Classification)算法是波达角(the Direction of Arrival,DOA)估计的经典算法之一,但其在二维DOA估计中因需进行二维谱峰搜索而计算量十分巨大.为降低MUSIC算法的计算量,本文在引入变换域DOA概念的基础上提出了一种能够适用于任意阵列结构的二维DOA快速估计算法,即变换域MUSIC(transformed do-main-MUSIC,TD-MUSIC)算法.理论分析和仿真实验表明:该算法不但将空间谱峰搜索的范围减小一半而且具有更低维度的噪声子空间,因而其计算量远小于MUSIC算法.同时,新算法具有比MUSIC更高的空间分辨率.
基金supported by the National Natural Science Foundation of China(61501142 61871149)the project supported by Discipline Construction Guiding Foundation in Harbin Institute of Technology(Weihai)(WH2-0160107)
文摘Finding the intersection of two subspaces is of great interest in many fields of signal processing. Over several decades,there have been numerous formulas discovered to solve this problem, among which the alternate projection method(APM) is the most popular one. However, APM suffers from high computational complexity, especially for real-time applications. Moreover, APM only gives the projection instead of the orthogonal basis of two given subspaces. This paper presents two alternate algorithms which have a closed form and reduced complexity as compared to the APM technique. Numerical simulations are conducted to verify the correctness and the effectiveness of the proposed methods.
文摘基于交替方向乘子法(alternating direction method of multipliers,ADMM)的线性规划(liner programming,LP)译码模型因其不会出现错误平台和具有最大似然认证的优点,广受译码研究者的关注。目前大多数ADMM算法采用的是泛洪调度策略(flooding,FL),该算法存在译码收敛速度过慢的问题。基于水平分层调度的交替方向乘子法的低密度奇偶校验(low density parity check,LDPC)码译码算法能够加速译码收敛速度,然而目前水平分层调度算法中的投影算法采用的为精确投影算法,复杂度较高。针对该问题,将近似投影算法和水平分层调度算法结合,提出基于近似投影的ADMM水平分层调度译码算法以提高译码的性能。仿真实验表明,相比其他算法,本文提出的算法的译码性能可提升0.1~0.3 dB,迭代次数可降低19%~40%,平均译码时间可减少21%~65%。
