共查询到20条相似文献,搜索用时 156 毫秒
1.
2.
3.
4.
窄波束全向接收的自适应天线阵研究 总被引:4,自引:0,他引:4
为了实现对短波频段全空域低信噪比信号的良好接收,本文提出了一种窄波束全向接收的知适应天线阵。文中首先简要回顾了自适应天线阵的基本理论,并针地短波波段频程较宽的特点,提出了一种接收信号频率决定阵元间距的阵元间距动态可变组阵方案,文末通过计算机仿真比较了该方案实现的窄波束全向接收自适应天线阵和常规短波天线阵的性能。 相似文献
5.
对功率反演自适应阵进行了分析研究。结果表明,这种天线阵能用来改善通信系统的信号干扰比,其性能是目标信号功率、干扰信号功率、热噪声功率、反馈环增益、信号到达角和信号带宽的函数。功率反演自适应阵与LMS自适应阵不同,它不需要参考信号,因而没有LMS自适应阵的局限性。 相似文献
6.
7.
GPS抗干扰自适应圆阵性能的研究 总被引:3,自引:1,他引:2
简述自适应天线阵的工作原理,并根据GPS接收机应用的高灵敏度,动态范围大以及接收天线阵元数目 不宜过多的特点,研究了在功率阻塞式干扰的情况下,功率倒置圆阵的性能,计算模拟结果表明 相似文献
8.
自适应天线阵抗干扰原理及对其干扰措施研究 总被引:4,自引:0,他引:4
从天线阵的方向图和阵输出的信/干噪比等方面对自适应天缄阵的抗干扰原理进行了理论和仿真分析,并对其的干扰方法进行了分析、研究和仿真,并依此提出性价比较好的干扰措施。 相似文献
9.
《电子科技文摘》2000,(2)
Y99-61821-1089 2002543出现衰落时 CDMA 的多信道干扰消除=Multichanndinterference cancellation for CDMA in the presence offading[会,英]/Ghazi-Moghadam,V.& Kaveh,M.//1998 32nd Asilomar Conference.Vol.2.—1089~1093(PC)提出了把干扰消除接收机作为 CDMA 系统用低复杂性接收机的建议。介绍了采用自适应天线阵的连续干扰消除接收机。提出两种方案,以使天线阵在各级适应用户之一和消除来自正进入下一级信号的用户。比较了两种方案在多径衰落环境中的性能,并说明了比单码元干扰消除接收机的改进。参7Y99-61821-1199 2002544卷积编码自适应 CDMA 接收机结构=A convolutional-ly-codeA adaptive CDMA receiver architecture[会,英]/ 相似文献
10.
针对基于功率倒置算法的空时自适应抗干扰技术中天线阵元间互耦误差严重恶化算法性能这一问题,分析比较了目前常见的应对解决方案,并提出一种新的可用于抗干扰卫星导航终端的天线阵列降耦方法。该方法通过在卫星导航抗干扰天线阵列中加载电磁谐振吸波器,降低天线阵元间互耦。实验数据表明,利用该方法可以使阵元间互耦降低10 dB,使抗干扰接收机最大抑制干信比提升5 dB。 相似文献
11.
12.
Jianfeng Liu 《International Journal of Electronics》2013,100(10):1749-1762
Conventional antenna array synthesis methods can give good performance for uniform spaced antenna arrays within desired performance bounds. However, due to the restriction of uniform antenna element spacing, a lot of elements are required. Because of the above-mentioned drawback, in this paper, a new approach is presented to synthesise uniform spaced antenna array using the minimum number of elements. This approach introduces the state-space model to represent the desired discrete array pattern that is sampled uniformly from ?1 to 1 corresponding to 0–180°, then uses the desired sampled array pattern directly to construct the forward–backward data matrix that is introduced to estimate the model parameters, from which the locations and excitations of the new antenna elements can be extracted. The appropriate roots that are located on the unit circle are selected to obtain new radiation pattern. Simulation results show the viability for both shaped-beam and pencil-beam designs. 相似文献
13.
Performance of adaptive array antenna with arbitrary geometry in the presence of mutual coupling 总被引:2,自引:0,他引:2
Qiaowei Yuan Qiang Chen Sawaya K. 《Antennas and Propagation, IEEE Transactions on》2006,54(7):1991-1996
The effect of the mutual coupling between the array elements on the performance of the adaptive array antennas (AAA) is investigated when the actual received voltages which include the mutual coupling are directly used to estimate the weight vector based on the adaptive algorithm. The output signal-to-interference-noise ratio (SINR), the convergence of the adaptive algorithm and the synthesized pattern are evaluated to study the effect due to the existence of the mutual coupling. It is found that the mutual coupling affects the antenna adaptive gain, but does not affect the adaptive processing. It is also found that the mutual coupling does not always degrade the iterative convergence of the adaptive algorithm. It is proved that any invertible matrix for compensating the mutual coupling cannot improve the output SINR. It is also indicated that the radiation pattern can be correctly synthesized in the presence of the mutual coupling by introducing the universal steering vector (USV) whose element corresponds to the array element pattern. 相似文献
14.
15.
16.
17.
提出了一种可重构的临近耦合印刷偶极子天线阵。其通过控制每个振子的间距和振子偏移中心馈线的距离实现方向图的改变,提出的可重构天线阵,将形成不同方向图的偶极子天线阵嵌套排布,并通过pin管开关切换不同的偶极子辐射单元组,从而实现天线方向图的重构,改变天线的最大辐射方向。仿真结果表明在9.8 GHz的中心频点上,该天线可实现最大辐射方向在0°和40°上切换:波束指向为0°方向时,最大增益为12 dBi;为40°时,最大增益为8.7 dBi,两种工作状态下天线输入端s11均优于-30 dB,匹配良好。 相似文献
18.
The performance of an adaptive array with two inverted-F elements is analyzed by using the method of moments. A random signal model for mobile communication in a typical urban area is used. Three-dimensional analysis is applied to give a clear expression of the array output signal-to-interference plus noise ratio (SINR) performance. Also, a factor called SINR pattern angle ratio (PAR) is introduced with which a quantitative evaluation of the SINR patterns becomes possible. By using the PAR, the array performance for different array parameters such as inverted-F antenna (IFA) element orientations, interelement spacings and incident signal directions are computed. As a result, the IFA element is found preferable to a quarterwave monopole array in the assumed signal environment 相似文献
19.
The radiation pattern of a small-size concentric ring array antenna does not remain φ-symmetric, if the array is made with an appreciably lesser number of antenna elements. The sidelobe level, first null beamwidth (FNBW), half-power beamwidth (HPBW), and the null depths of the radiation pattern change significantly in different φ planes. An efficient pattern synthesis method has been developed in this work to reduce the variation of sidelobe level, FNBW, and HPBW of a small-size concentric ring array of isotropic antennas, for different φ cuts. It is done by finding out an optimum set of amplitude distribution of the array elements using firefly algorithm. The sidelobe level and the first null depth of the array are kept below a desired value for all the defined φ cuts. The directivity of the optimized array and the uniform array has been computed. The variation of all these parameters for different φ cuts has been compared to the same array with uniform excitation among the elements. 相似文献
20.
The X -band microstrip slot antenna array is described as an attempt to achieve moderate bandwidth and overcome the problems of radiation from microstrip feed lines and surface waves in the dielectric. The discussion covers development of a mathematical simulation that computes the radiation pattern of a single microstrip slot and the feeding microstripline; construction of a uniform broadband microstrip slot antenna array; development of a mathematical simulation that computes the radiation pattern in the H - and E -planes; and investigation of the mutual coupling between the slots. A comparison is made between computed and measured results at X -band frequencies 相似文献