2005/11/07 | 天线功率波瓣[Antenna Power Pattern]
类别(Ω〖物理〗) | 评论(1) | 阅读(70) | 发表于 22:21
Also called the beam pattern, pattern function, or weighting function. It can be defined from the observed flux density equation
(1)

where is the antenna pattern normalized such that
(2)

The factor of is sometimes absorbed into the definition of , so that
(3)

More rigorously, the antenna pattern is defined by the antenna's response to a point source at . Let be the measured (complex) electric field,
(4)

Therefore, is also a function of polarization. The diffraction pattern for a circular aperture (or antenna) is
(5)

for small . Let
(6)

For small x, use
(7)

so


(8)

so


(9)

Now,


(10)

So, for small x,
(11)

The beam width is
(12)

so
(13)
0

评论Comments

日志分类
首页[1408]
∑〖数学〗[349]
Ω〖物理〗[357]
¤〖天文〗[343]
℃〖化学〗[359]