The vital problem of the mobile communication is how to using the limited spectrum resource to match the distribution of user demand in the space and time.

其中移动通信技术最主要关注的一个问题就是如何利用有限的频谱资源，满足用户需求在空间和时间上的分布。

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The utilization rate of licensed spectrum is very low in the time domain, frequency domain and space domain, while the unlicensed band is overcrowded seriously.

大部分授权频段在时域、频域和空间域的利用率很低，而公共频段出现了严重的频谱拥挤。

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RS-images record geophysical changing information in space area?time area and spectrum area.

遥感图像记录了地物在空间域、时间域、光谱域的变化信息。

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