Question

帮翻译个电子类专业英语 论文摘要 很重要 不要在线翻译

When the call is completed, the telephones at each end are returned to their cradles,
breaking the circuit of each subscriber loop. This, of course, is analogous to turning off
a light; the current stops flowing. Phase 3 of the telephone call begins. It terminates the
call, and the connecting circuit in the switch is taken down and freed-up for another
user. Both subscriber loops are now idle. If a third user tries to call either subscriber
during stages 2 and 3, she/ he is returned a busy-back by the exchange (serving switch).
This is the familiar “busy signal,” a tone with a particular cadence. The return of the
busy-back is a form of signaling called call-progress signaling.
Suppose now that a subscriber wishes to call another telephone subscriber outside the
local serving area of her/ his switch. The call setup will be similar as before, except that
at the calling subscriber serving switch the call will be connected to an outgoing trunk.
As shown in Figure 1.4, trunks are transmission pathways that interconnect switches. To
repeat: subscriber loops connect end-users (subscriber) to a local serving switch; trunks
interconnect exchanges or switches.
The IEEE (Ref. 2) defines a trunk as “a transmission path between exchanges or
central offices.” The word transmission in the IEEE definition refers to one (or several)
transmission media. The medium might be wire-pair cable, fiber optic cable, microwave
radio and, stretching the imagination, satellite communications. In the conventional
telephone plant, coaxial cable has fallen out of favor as a transmission medium
for this application. Of course, in the long-distance plant, satellite communication isfairly widely employed, particularly for international service. Our preceding reference
was for local service.

Answer 1

当电话完成时,电话,在每个年底被归还到各自的销,

打破了电路的每一个用户环路上。当然,这好比关掉

一盏灯,电流就停止流动。第三阶段的电话开始。它终止

打电话给你,连接电路开关是取下来freed-up于另一个

用户。两个用户环路现在闲着。如果第三个用户试图再也呼叫用户

(二)、(三)在阶段,她/他是返回了一个由交易所(服务busy-back开关)。

这是常见的“繁忙讯号,”一个音调是与一个特定的基调。回归的

busy-back是一种信号称为call-progress信号传导。

假如现在一个用户想打电话给另外一个电话用户在

当地的服务面积她/他的开关。调用启动相似,除了像以前那样

在通话用户服务开关电话将会被连接到一个好交际的箱子。

如图14、中继线是传输路径的连接开关。到

再说一遍:用户环连接用户(订户)当地的服务开关;的树干

连接交流或者开关。

Answer 2

translate the underlined sentence into chinese

Answer 3

When the call is completed, the telephones at each end are returned to their cradles当通话结束以后，每一个终端的电话机都回复到他们的初始状态。,
breaking the circuit of each subscriber loop.切断各自的用户线路 This, of course, is analogous to turning off a light;就好像关断一盏电灯 the current stops flowing电流停止流动.