电信专业英英词典C-2

　　Cassegrain Antenna¹ - An antenna that places a subreflector at the focal point to reflect energy to or from a feed located at the apex² of the main reflector.

　　CB - This stands for Citizen's Band and is low-power (up to 4 Watts), public radio that does not require FCC approval.

　　CD - See Carrier Detect.

　　CDMA - This stands for Code Division Multiple Access and refers to a multiple-access scheme where stations use wide-spectrum modulations and orthogonal codes to reduce the chance of interfering³ with each other.

　　Central Office (CO) - This is a place where lines are joined to switching equipment (which control connections).

　　Channel - A frequency band, 6 MHz wide in the US, in which a specific broadcast signal is transmitted. Channel frequencies are determined⁴ in the US by the Federal Communications Commission (FCC).

　　Character - This is a letter, numeral, or symbol.

　　Characters per Second (CPS) - This is the number of characters that can be sent over the phone lines in 1 second.

　　Chat - A mode that allows two or more people to communicate with each other in real time over a network using modems⁵.

　　Checksum - This is the sum of a group of data items that is used for error checking. Received information packets must have the same number of bits present during the initial transmission.

　　Chip - This is the physical structure of an integrated circuit.

　　Circuit - This is an electrical device that provides a path for electrical current to flow, or more generally, it is a journey or route all the way around a particular place or area.

　　Circular Polarization - Some satellites transmit both right-hand rotating and left-hand rotating signals simultaneously⁶ on the same frequency. This technique effectively doubles the channel carrying capacity of the satellite.

1 antenna   

n.触角，触须；天线

参考例句：

• The workman fixed the antenna to the roof of the house.工人把天线固定在房顶上。
• In our village, there is an antenna on every roof for receiving TV signals.在我们村里，每家房顶上都有天线接收电视信号。

2 apex   

n.顶点，最高点

参考例句：

• He reached the apex of power in the early 1930s.他在三十年代初达到了权力的顶峰。
• His election to the presidency was the apex of his career.当选总统是他一生事业的顶峰。

3 interfering   

adj. 妨碍的 动词interfere的现在分词

参考例句：

• He's an interfering old busybody! 他老爱管闲事！
• I wish my mother would stop interfering and let me make my own decisions. 我希望我母亲不再干预，让我自己拿主意。

4 determined   

adj.坚定的；有决心的

参考例句：

• I have determined on going to Tibet after graduation.我已决定毕业后去西藏。
• He determined to view the rooms behind the office.他决定查看一下办公室后面的房间。

5 modems   

n.调制解调器( modem的名词复数 )

参考例句：

• Yes, floppy day, as did 9600 baud dial up modems. 是的，当时软件是最主要的工具，还有9600波特拨号调制解调器。 来自互联网
• Extra settings for configuring BAD modems that cannot identify proper disconnect tone. 额外的设置，配置不好的调制解调器不能确定适当的断开的语调。 来自互联网

6 simultaneously   

adv.同时发生地，同时进行地

参考例句：

• The radar beam can track a number of targets almost simultaneously.雷达波几乎可以同时追着多个目标。
• The Windows allow a computer user to execute multiple programs simultaneously.Windows允许计算机用户同时运行多个程序。