将ECI转换成ECEF坐标

将ECI的位置、速度、加速度转换成ECEF的位置、速度、加速度。

 ECEF，earth centered eath fixed

   该坐标系以地球质心为原点，Z轴向北沿地球自转轴方向，X轴指向经纬度的（0，0）位置，右手系Y轴指向90度经线。该系与地球一同转动。

ECI，earth centered inertial

   坐标原点取在地心，X轴指向春分点，Z轴指向北极，Y轴与前者构成右手系。该系不与地球一同转动，因此可以应用牛顿定律。

Convert ECI to ECEF Coordinates

Convert ECI (CIS, Epoch J2000.0) Coordinates to WGS 84 (CTS, ECEF) Coordinates. This function has been vectorized for speed.

Example Function Call:

>> [r_ECEF v_ECEF a_ECEF] = ECItoECEF(JD,r_ECI,v_ECI,a_ECI);

Where:

JD is the Julian Date vector [1 x N] (units are in days)

r_ECI is the position vector [3 x N] (any units are permitted)

v_ECI is the velocity vector [3 x N] (any units are permitted)

a_ECI is the acceleration vector [3 x N] (any units are permitted)