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961.
阵列天线互耦补偿技术研究 总被引:3,自引:0,他引:3
分析阵列天线的互耦机理,利用电磁散射理论研究阵列天线的散射特性,得到阵列天线的散射矩阵,并根据散射矩阵中的实际物理意义,将矩阵进行分解,推导出阵列天线的互耦补偿公式,避免了复杂的计算,并在实际测试数据的基础上,利用提出的算法进行互耦补偿,验证了该算法的有效性。 相似文献
962.
This paper analyzes the achievable sum‐rate of correlated two‐antenna multiple‐input multiple‐output (MIMO) uplink channels. Most of previous works have considered the case when a single user has multiple transmit antennas (i.e. multi‐antenna single‐user scenario). This paper considers the case when two‐antenna MIMO uplink channels comprise two users with a single transmit antenna (i.e. single‐antenna two‐user scenario). The analytic and simulation results show that the achievable sum‐rate of correlated single‐antenna two‐user MIMO uplink channels highly depends on the angle difference between the receive correlation coefficients of two users. It is also shown that the achievable sum‐rate of correlated single‐antenna two‐user MIMO uplink channels is larger than that of correlated two‐antenna single‐user MIMO uplink channels and can even be larger than that of independent and identically distributed Rayleigh two‐antenna MIMO uplink channels. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
963.
Moon-Sik Lee 《ETRI Journal》2009,31(3):321-323
A wideband beamforming algorithm for estimating the azimuth angle, elevation angle, velocity, and range using a planar phased radar array with antenna switching is proposed. It uses the time-variant steering vector model. Simulation results illustrating the performance of the proposed beamformer are presented. 相似文献
964.
A switchable Yagi-Uda antenna prototype with radiation pattern reconfiguration is presented in this letter. The proposed reconfigurable antenna is based on the concept of switching between the reflector and director of a Yagi-Uda antenna using a radio frequency PIN diode. As a result, the minimum/maximum radiation can be steered towards desired signals or away from interfering signals in opposite directions. The measured 10 dB impedance bandwidth and gain are 210 MHz (7%) and 8.02 dBi at 3 GHz, respectively. Details of the antenna design and its performance are described and empirically analyzed. 相似文献
965.
Youngje Sung 《ETRI Journal》2009,31(5):506-509
A novel design of a compact square‐ring slot microstrip antenna for achieving circular polarization (CP) operation is proposed and experimentally studied. By using an arrow‐shaped slot structure as a radiating element, the resonant frequency of the proposed antenna is significantly lowered, which can lead to a large size reduction for fixed frequency operation. The CP radiation characteristics are achieved by loading with proper asymmetry, which can be placed diagonally. A prototype of the proposed design is implemented and its performance is measured. Measured results show that radiation patterns with good CP characteristics are obtained at the resonant frequency. 相似文献
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969.
Ken Albrecht Yuto Kasai Kimihisa Yamamoto 《Journal of Inorganic and Organometallic Polymers and Materials》2009,19(1):118-123
The fluorescence properties of double layer-type dendrimers with carbazole as the outer layer and phenylazomethine as the
inner layer of the dendron with a zinc porphyrin core were studied. Based on the fluorescence quantum yield (solution), the
effect of the bulky dendron to inhibit the interaction of the chromophores was confirmed. Additionally, the efficient light-harvesting
property of the double layer-type dendron was revealed by the fluorescence measurement at several excitation wavelengths.
These dendrimers were used as an emitting-layer in an OLED device. The electroluminescence of the core porphyrin was observed
and it was shown that the double layer-type dendrimer with a luminescent core has the potential to be a hole-transporting/emitting
material. 相似文献
970.
分析了四大车走行定位控制的原理,阐述了编码电缆的原理结构,介绍了地址检测的方法,探讨了梅山1,2号焦炉无线位置检测系统的特点,以推广感应无线技术在焦炉四大车定位中的应用。 相似文献