智能天线中一种新的三维波束形成方法

doi:1000-436X(2005)01-0027-07

摘要/Abstract

摘要：

提出了用分布于x?y?z三轴上的三个阵元估计扩频信号各条多径的来波方向（DOA）的方法，以及用由x?y均匀平面圆阵和z轴直线阵组成的阵列天线形成3维波束的方法。根据CDMA信号模型和多径信道模型，用最大似然（ML）法分别估计出信号到达 3 个阵元的复信道响应，并利用复信道响应的幅角来估计各条多径信号的 DOA；然后在已有最小均方误差（MMSE）法和最小二乘（LS）法的基础上生成带限制条件的扩展 MMSE （EMMSE）法形成3维波束。模拟表明，给出的DOA估计方法具有很高的精度，而EMMSE方法形成的波束主瓣窄，旁瓣被抑制，有很高的输出信干噪比。

关键词: 扩展最小均方误差法, 最小二乘法, 最大似然法, 到达时延, 来波方向

Abstract:

An effective method of estimating the directions of arrival(DOA) of multipath of spread-spectrum signals using three sensors on x?y?z axis and forming 3-dimension beam using array antenna consisted of x?y uniform plane circular array and z axis linear array is proposed. Based upon the signal model and the multipath channel model of CDMA, the complex channel responses of arriving at three sensors is estimated by using maximum-likelihood estimation method. Then by using the complex angles of these responses, DOAs of multipath of signals can be estimated. Based on existing minimum mean square error(MMSE) method and least square(LS) method, an extended minimum mean square error(EMMSE) method with constrained conditions is also proposed to form 3-dimension beam. Simulation results show this DOA estimating method has high accuracy and EMMSE method has high output SINR with narrow beamwidth of the main lobe and small side lobes.

Key words: extended minimum mean square error method, least square method, maximum-likelihood method, time of arrival, direction of arrival

沈建锋,王宗欣. 智能天线中一种新的三维波束形成方法[J]. 通信学报, 2005, 26(1): 27-33.

Jian-feng SHEN,Zong-xin WANG. A new 3-dimension beamforming method in smart antenna[J]. Journal on Communications, 2005, 26(1): 27-33.

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参考文献 8

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用户	路径	真实方位角	估计方位角	估计误差	真实仰角	估计仰角	估计误差
	1	0.1927	0.1486	?0.0441	0.0024	0.0064	0.0040
1
	2	?2.8868	?2.9015	?0.0147	?0.4342	?0.4884	?0.0542
	1	1.5477	1.5468	?0.0009	?1.3058	?1.3078	?0.0020
2
	2	0.8024	0.8031	0.0007	?0.7972	?0.7965	0.0007
	1	?3.0705	?3.1416	?0.0711	1.5182	1.4443	?0.0739
3
	2	?2.5701	?2.6155	?0.0454	0.2108	0.2052	?0.0056
	1	1.5817	1.5807	?0.0010	?0.4440	?0.4522	?0.0082
4
	2	1.1236	1.1187	?0.0049	?0.0554	?0.0556	?0.0002
	1	2.9704	2.9900	0.0196	1.1930	1.1939	0.0009
5
	2	?0.6499	?0.6561	?0.0062	0.1328	0.0977	?0.0351

用户	路径	衰减系数	MMSE		LS		EMMSE
用户	路径	衰减系数	加权输出信号模	天线增益	加权输出信号模	天线增益	加权输出信号模	天线增益
	1	0.8971	0.8687	0.9683	0.8847	0.9861	0.8971	1.0000
1
	2	0.6133	0.0695	0.1134	0.0942	0.1536	0.0016	0.0026
	1	0.7550	0.0085	0.0112	0.0063	0.0083	0.0033	0.0043
2
	2	0.5081	0.0409	0.0805	0.0684	0.1347	0.0004	0.0008
	1	0.8428	0.0452	0.0536	0.0466	0.0553	0.0032	0.0038
3
	2	0.7055	0.0096	0.0137	0.0184	0.0261	0.0014	0.0020
	1	0.8205	0.1789	0.2180	0.2289	0.2790	0.0020	0.0024
4
	2	0.7107	0.0731	0.1029	0.1068	0.1503	0.0018	0.0025
	1	0.7965	0.0009	0.0011	0.0004	0.0005	0.0021	0.0027
5
	2	0.6023	0.0272	0.0451	0.0267	0.0443	0.0013	0.0022
SINR		0.1751 (输入)	17.182 (输出)		9.5694 (输出)		625.00 (输出)