A sphere, in contrast, concentrates its beam to a line - which is why a "linefeed" antenna was originally used at Arecibo.
球形的则不同，它会把波束汇聚到一条线上——这就是为什么阿雷西博先前使用的是“线反馈”天线。
2
This means that the SETI receiver was perched permanently above the Arecibo dish at the base of the aging linefeedantenna.
也就是说SETI的接收器永久的占据着阿雷西博碟型天线上老化的线性馈源的底部。
3
The radiating element of array antenna is air dielectric microstrip patch antenna, which has high efficiency, and the feed network is low loss air strip, which can reduce the loss of the feed line.