And even if these problems are overcome,using existing satellite technology it may not be possible to place enough of these devices in space to achieve full coverage because of the billions of dollars it takes to build and launch them.

• 即使这些问题得到解决，现有的卫星技术也可能无法在太空安置足够多的装置以实现全球覆盖，因为制造和发射这些设备需要数十亿美元。