In order to command the use of radio spectrum, the radio spectrum management department and the security department must keep communication signals under surveillance.

为了更好地掌握无线电频谱利用情况，无线电频谱管理部门和国家安全部门必须对通信信号进行监控。

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Officers had planned to keep McQuade under armed surveillance after the loan was given, but had lost him within days.

BBC: Cleveland chief constable Sean Price ordered the inquiry