To cope with the problem of phase shifts caused by different propagation paths (especially in HF links), the modulation is done in differential phase shift keying (DPSK).

为了克服由多径传播造成的相移失真难题(特别是在HF链路里)，调制采用差分相移键控(DPSK)来完成。

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The first segment 310 of the TPS data block (bit so) is an initialization bit for a differential binary phase shift keying (2-PSK) modulation.

TPS数据块的第一段310（比特S0）为差分二进制相移键控调变的初始比特。

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