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美空军已获准对GPS卫星的三项研制工作：改进现役GPS的ⅡR和ⅡF型两种型别卫星，开始内部研究下一代GPS—Ⅲ卫星的体系结构。 美空军同洛克希德·马丁公司签订一项价值5300万美元的合同，以改进该公司正在制造的12颗GPS—ⅡR型卫星，加载第二个民用信号和新的军用M码信号。
The U.S. Air Force has been approved to develop three GPS satellites: two types of satellites, Type IIR and Type IIF, for active GPS, and begin an internal study of the architecture of the next generation of GPS-III satellites. The U.S. Air Force signed a $ 53 million contract with Lockheed Martin to improve the 12 GPS-IIR satellites the company is building, loading a second civil signal and a new military M-code signal.