英语语法分析

Radar altimeters are used in aircraft to indicate height above the ground of sea.

雷达高度表用以指示飞机相对于地面或海平面的高度。

This paper presents a system simulation method of pulse Doppler radar altimeters with frequency agility.

本文提出了雷达高度计的一种系统模拟方法。

Radio altimeters measure the distance of an aircraft above the ground rather than above sea level, they are used in automatic navigation and Blind-landing systems.

无线电高度表测量的是飞机离地面而不是离海平面的距离，用于自动导航及仪表着陆系统上。