McCaw is still eyeing Iridium's billing system.

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Last fall he was ready to unveil it as a 288-satellite system very much like Iridium.

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Its Iridium satellite-based global phone system switches all calls in the sky without using any ground stations, an impossibly difficult task.

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McCaw also has intellectual property rights to a system that connects low-orbit satellite systems like Iridium with midaltitude projects like ICO.

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Each of Iridium's 66 satellites has its own phone-switching system, boosting coverage and performance at a cost of complexity and weight.

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Iridium had spectrum and rights to operate in 150 countries, as well as a global billing system.

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