电子信息工程专业英语考试要点总结(2)

description into a list of logic gates and their interconnections,called the

"netlis". Every logic synthesis program understands some subset of

Verilog and VHDL.

4."复杂可编程逻辑器件"是一种在逻辑模块之间具有可编程互连的可

编程逻辑器件。多数复杂可编程逻辑器件是基于电可擦写可编程只读

存储器和闪存的。

CPLD(Complex PLD)is a programmable logic device that includes a

reprogrammable interconnect between the logic blocks.CPLDs are mostly

EEPROM and flash based.

5.数字信号处理器(DSP)是无数家用和商用系统的关键部分，其应用

领域与日俱增。因此，DSP 正在成为技术专家和工程师专业知识的重

要组成部分之一。

Digital signal processing is an essential element of countless home and

business systems. Its domain can only increase as time proceeds.Thus,

DSP is becoming an essential area of expertise for technologists and

engineers.

6.信号(如声音，光和电压)是携带信息的变化。模拟信号是现实世界

中的信号。模拟信号在每个时间点上都有定义，其幅度的取值是无限

的。

Signals ,like sound,light,or voltage,are information-bearing variations.

Analog signals are real-world signals.They are defined at every point in

time and may take an infinite number of possible amplitudes.

英译汉句子

ing better compression algorithms, it is possible to get the speech

down to 4kbps , in which case six users can be stuffed into a frame, as

illustrated in Figure 11.(b).From the operator's perspective , being able to

squeeze three to six times as many D-AMPS user is a huge win and

explains much of the popularity of PCS.

如果使用更好的压缩算法，还可以把语音数据率降至4kbps；这

样的话，一帧就可以容纳6 位用户了。在运营商看来，“3—6 位D—

AMPS 用户只需占用相当于1 位AMPS 用户所需的带宽”是巨大的

成功，而且在很大程度上解释了“个人通信业务”（PCS,Personal

Communication Service）普及的原因。

2.CDMA is completely different from AMPS ,D-AMPS, and GSM.

Instead of dividing the allowed frequency range into a few hundred

narrow channels, CDMA allows each station to transmit over the entire

frequency spectrum all the time .Multiple simultaneous transmissions are

separated using coding theory. CDMA also relaxes the assumption that

colliding frames are totally garbled . Instead , it assumes that multiple

signals add linearly.

CDMA 和AMPS、D—AMPS 及GSM 完全不同。CDMA 没有将

可用频带分割为几百个窄带信道，而是允许信号在整个频谱范围内传

送。利用编码原理，CDMA 可以将多个同时传送的信号分离开来。

在CDMA 中，“相遇数据帧会造成数据混淆”的想法不存在了——