This is found by observing the doppler shift in the frequency of the radio signals broadcast from the satellite. 这是通过观测卫星所发射的无线电信号频率中多普勒偏移来确定的。
By sheer coincidence, a trio of earth-monitoring satellites gave modelers the pristine, undistorted wave heights they needed for the Indian Ocean tsunami. 十分巧合的是,有一组地球观测卫星提供了最原始且如实的海啸波高值,这是模型设计师模拟印度洋海啸时不可或缺的。