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英文report怎么写 Phased Array Antennas For Mobile Earth






A phased array antenna is a multi-element structure, where the radiation beam width and direction can be controlled electronically; this report will discuss how the technology operates and cover some background theory.

The performance capacity of phased array antenna will be analyzed and applied to a mobile earth station scenario; its ability to combat the effects of multi-path fading in a mobile satellite communications link will be discussed.

The performance of the phased array antenna will be compared to an omni-directional antenna also in the same mobile earth station scenario.

Finally the report will look at some of the main applications of phased array antennas, in satellite and radar systems.

2 Phased array antenna technology

“一个无线电天线可以被定义为与导波和自由空间波之间的过渡区域相关联的结构,或反之亦然。天线转换电子photons1,反之亦然[ 1 ]。”

相控阵天线是由多个天线单元;他们驱使和每个元素具有可控的阶段,为了扫描光束在空间中给定的角度。在每个元素的振幅也可以被控制,以提供图案形成。阵列可以允许更精确的控制的辐射图案,因此导致在较低的旁瓣或图案整形。然而,使用阵列的主要原因是有一个指令束,可以电子定位[ 2 ]。

“A radio antenna may be defined as the structure associated with the region of transition between a guided wave and a free-space wave, or vice versa. Antennas convert electrons to photons1, or vice versa [1].”

A phased array antenna is comprised of multiple antenna elements; they are driven coherently and have controllable phase at each of the elements, in order to scan a beam to given angles in space. The amplitude at each element can also be controlled to provide pattern shaping. Arrays can allow more precise control of the radiation pattern, therefore resulting in lower side lobes or pattern shaping. However, the main reason for using arrays is to have a directive beam that can be positioned electronically [2].