It’s when you are out of cellphone range and farthest from help when you’re

游客2024-05-16  14

问题     It’s when you are out of cellphone range and farthest from help when you’re going to need urgent assistance. Think of being aboard a boat sinking at sea, or crashing a motorcycle in the desert while on a camping trip.
    That’s what satellite phones are for—they send a signal directly to a satellite from anywhere with a clear view of the sky without need of a cell tower. But with per-minute fees of $ 1 or more, you’ll still need a regular mobile phone for everyday use. That means you need two phones. Just what you want when hiking—two weighty pieces of hardware to tote (随身携带). But now there is a hybrid (合成的) mobile-satellite phone, a single device that can connect to either network. Called the TerreStar Genus, this phone is available through AT&T for $ 1 070. As with any hybrid, compromises are made. For one, the mobile phone portion runs on the clunky Windows Mobile 6.5.3 operating system, so there isn’t the intuitive ease of the newer Windows Phone 7 system.
    Using the satellite side of the phone also requires some adjustments. Because the phone has no external antenna (天线), you have to hold the phone just so, or your palm will block the signal. You also have to make sure the phone is oriented toward the TerreStar-1 satellite at 111 degrees west. Also make sure to listen to the phone using the ear nearest the satellite, as your head can block the signal, along with mountains, trees or buildings.
    Some of those issues can be addressed with a $ 300 optional external antenna, but that adds more bulk. Even with the antenna the Genus is limited to North America and up to 200 miles offshore. Service excludes Mexico and Canada, but Canada is within range, and will be offered later, said TerreStar.
    Another thing to get used to is the time lag. It can take up to two minutes for the phone to initialize (初始化), acquire and connect to the satellite. You do get audible alerts to let you know the phone is working on it. When you get the connection, there are pauses between the time you speak and the listener hears what you say, much like first generation VoIP calls. The reason is that the satellite bouncing your call is 22 000 miles or more away. All of that sophisticated hardware takes a toll on the batteries. In satellite mode expect 4 hours of standby time and 1.3 hours talk time.
    TerreStar said the phone is made with first responders in mind—firefighters and the police who need communications in an emergency when cell towers might be out. But it is also an option for anyone who wants the security of a communications backup system—and is willing to pay for it. [br] Why does the satellite phone need adjustments?

选项 A、Because the satellite bouncing one’s call is 22 000 miles or more away.
B、Because one’s head may block the signal along with trees and buildings.
C、Because the external antenna is not installed in the satellite phone.
D、Because it needs time to initialize, acquire and connect to the satellite.

答案 C

解析 细节辨认题。定位句指出,卫星电话需要一些调整,因为它没有外置天线。因此,正确答案为C)“因为卫星电话没有安装外置天线”。
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