1.what systems are included in modern dldctronic communication systems?
Modern electronic communication systems include metallic cable systems,microwave and satellite radio systems,and optical fiber systems.
2.what the difference between analog signal,discrete signal and digital signal?
Analog signal:The signal which time and amplitude are continuous distribution .
Discrete signal:The signal which time is discrete distribution.
Digital signal:The signal which time and amplitude are discrete distribution.
3.what is TD-SCDMA?
TD-SCDMA is one of the five IMT-2000 standards accepted by the ITU.
4.what are the main benefits?
The main benefits of TD-SCDMA are that it an be implemented less expensively than comparable 3G systems since it is much more spectrum efficient and is compatible with GSM network elements,allowing 3G services without installation of completely new infrastructure.
5.what is the data rates TD-SCDMA can provide?
From 1.2 k/bps to 2 M/bps
6.what is asymmetric?
For nom rel-time applications like e-maill Internet access ,timing constraints are less strict and the generated traffic.
7.what is cell breathing effect?
Due to intra-cell interference cell area reduced when data rates or numbers of grow.
1.电子束以均匀的速率扫描每一行，然后飞速返回去扫描下一行，直到被扫描的图像按所希望的顺序分割成行。
This electron beam sweeps across each line at a uniform rate,then files back to scan another line directly below the previous one and so on until the horizontal lines into which it is desired to break or split the picture have been scanned in the desired sequence.
2.因此在技术上完全可以可能实现全国性的集成发送网络。这种网络容量大由计算机控制，并通过卫星和海底电缆实现全球互联。提供世界范围高速，可靠的通信。
The technical possibilities could well exist ,there for of nation-wide integrated transmission network of high capacity ,controlled by computer,interconnect globally by satellite and submarine cable ,providing speedy and reliable communications throughout the world.
3.电子通信系统的基本作用是把信息从此地传送到彼地。
The fundamental purpose of an electronic communication system is to transfer information from one place to another.
4.发射机中的信号处理单元对信源进行调理，以便更有效的传递。
The signal-processing block at the transmitter conditions the source for more efficient transmission.
5.此外信号处理器还可以给数码子加入奇偶校验位，即提供信道编码 ，使的接收机的信号处理器可以进行误码检测和纠错，以减少或消除由信道噪声所引起的误码。
In addition ,the signal processor may also add parity bits to the digital word to provide channel coding so that error detection and correction can be used by the signal processor in the receiver to reduce or eliminate bit errors that caused by
noise in the channel.
6.作为一种以同步模式运行的结合CDMA自适应技术的高级TDMA、TDD系统，TD-SCDMA具有对称电路交换服务业务（如语音和视频）和非对称分组交换服务业务（如手机上网）。
Designed as an advanced TDMA,TDD system with an adaptive CDMA component operating in synchronous mode,TD-SCDMA masters both symmetric circuits switched services (such as speech or video)as well as asymmetric packet switched services(such mobile internet access).
7.TD-SCDMA的主要优势在于他的运营费用比其他3G系统低，因为他的频谱利用率较高而且与GSM网络组件兼容，使的3G业务在GSM系统中实现而不需要安装新的基础设施。
The main benefits of TD-SCDMA are that it can be implemented less expensively than comparable 3G systems since it is much more spectrum efficient and is compatible with GSM network element, allowing 3G services without installation of completely new infrastructure.
8.智能天线的高方向性和灵敏度连同终端只有在激活的时间内才发射功率这一事实有助于保持终端的低功耗，这带来更多具有成本效益的手持设备。
The high directivity and sensibility of smart antenna together with the fact that terminals transmit power only during active timeslots contributes to keep the terminal’s power consumption low ,which leads to more cost effective handsets.
9.TD-SCDMA的主要优势在于它的运营费比其他3G系统低，因为它的频率利用率较高，而且与GSM网络组件兼容，使得3G业务在GSM系统中能够实现而不需要安装新的基础设施。
The main benefits of TD-SCDMA are that it can be implemented less expensively than comparable 3G systems since it is much more spectrum efficient and is compatible with GSM network elements,allowing 3G services without installation of completely new infrastructure.
10.相反，TD-SCDMA根据数据负荷在单一而非对的载频内调整上下行的（时隙）比率，因此能够有效的利用频谱，并提供1.2kbps-2Mbps数据传输频率。
On the contrary,TS-SCDMA adapts the uplink/downlink radio according ro the data load within a single unpaired frequency thus utilizing the spectrum more efficiently,and provides dara rates ranging form 12kbps to 2Mbps.
discrete 离散的，分离的，不连续 ionospheric reflection 电离层反射
oscilloscope 示波器 multiplexed system多路通信系统 3GPP第三代伙伴计划
bandwidth 带宽 frequency assignment频率配置 CATT中国电信科学技术研究院
Interference 干扰 spread spectrum system 扩频系统UMTS通用移动通信系统
binary-coded number 二进制编码数band pass signal带通信号
Hi-Fi 高保真度 ITU(International telecommunication union国际电信联盟
electromagnetic induction..电磁感应 amateur radio业余无线电
ADC模数变换器 parity bit奇偶校验位 ATM异步传输模式
VLSI 超大规模
集成 the over frequency plan频率整体规划
block diagram 方框图 HDTV(high definition Television)高清电视
PSK 相移键控 single sideband(SSB)单边带 LIE 局部热动平衡
discrete signal 时间离散分布信号 signal--to--noise信噪比 oscillator
PTN 公用电信网络 Ministry of Industry and Information Technology工业和信息化部
.a full array 全方位，全面的 FAX 电传真 transistor晶体管
.amplitude modulation (AM) 幅度调制 public telecommunications network(PTN)公网电信网络 IEEE电气与电子工程师协会
.negative-feedback amplifier 负反馈放大器 linear integrated circuit线性集成电路
PCM(pulse-code Modulation) 脉冲编码调制 stereo FM立体声调频
.time-division multiplexing(TDM) 时分多路 cellular telephone蜂窝电话
.adaptive equalization 自适应均衡 CDMA码多分址
.random access memory(RAM) 随机存取存储器 SDMA空多分址TDMA时多分址
ISDN(Integrated Services Digital Network)综合业务数字网 GSM 通用移动通信系统
Los propagation 视线传播 k/bps千比特每秒 TDD时分多址
.triode vacuum tube 真空三极管 TD-SCDMA时分同步码分多址
.error --correction code纠错编码 W-CDMA宽带CDMA