通信系统

The paper expands some important links of the communications system which include channel, noise, digital transmission of analog signal, channel encode and signal modulation.

本文在深刻理解通信系统理论的基础上利用MATLAB强大的仿真功能，设计了许多具体的通信系统仿真模型。

The performance of bit error rate, asymptotic multiuser efficiency, near-far resistance, local near-far resistance, complexity, and processing delay of decorrelating multiuser detector alleviating edge effect is quantitatively analyzed.

多用户检测与空时处理技术是第三代移动通信系统以及未来第四代移动通信系统中的两项关键技术，在性能上表现出的潜力对未来的无线高速Internet以及多媒体业务具有极大的诱惑力。

With uMobility, Strata CIX users turn their smartphones into their office telephones both in and out of the office, while continuing to use the same smartphones for their private calls. And, they can do it without having to provide their private mobile numbers to their callers.

东芝美国资讯系统公司通信系统事业部主管统一通信解决方案的产品总监David Fridley 说：有了uMobility，无论在办公室还是在户外，Strata CIX用户们的智能手机能接听办公室固定电话，与私人电话使用不冲突，并且确保私人电话号码不被透漏给他人。

A mobile node in a packet commination system including a node, a link and a base station that complies with an Edge Mobility scheme is disclosed.

公开了一种分组通信系统中的移动节点，该分组通信系统包括符合边缘移动性方案的节点、链路和基站。

In order to improve the transmission quality and reliability of the digital communication system, channel coding is proposed.

详细说明：为了改善数字通信系统的传输质量，提高数字通信系统传输的可靠性引入信道编码。

For wireless communication, channel diversity is an effective method to achieve reliable communication and improve the system performance.

对于无线通信系统来说，信道分集是实现可靠通信、提高通信性能的有效方法。

Satellite mobile communication system has become one of the hot communication research fields and a useful tool for modern communication.

摘要卫星移动通信系统已经成为当前通信领域中发展非常迅速的研究方向和现代通信强有力的手段之一。

Convolutional Encoding is one of encoding methods commonly used in the deep space communication systems and the wireless communication systems.

卷积编码是深空通信系统和无线通信系统中常用的一种编码方式。

Especially in military affairs, it is the vital part in military operations. Short-wave communication is attractive because only little power and proper expenditure is needed when it is used for long distance communication. For this valuable trait, many country have expanded the area of short-wave communication's research, thus there has become more and more new-model communication system.

短波通信之所以能吸引用户用它传递信息，最基本的原因是由于进行远距离通信时，仅需要不大的发射功率和适中的设备费用，这一宝贵的优点，使得世界各国近年来加紧了短波通信的研究，出现了各种新型的短波通信系统。

The results of the simulation analysis and experiments indicate that the loss of ultraviolet scattering transmission in atmosphere is high because of the particle scattering and absorbing in solar-blind zone; that is, the received power can descend 20 dB with the distance increasing 10 times. Therefore, the ultraviolet scattering is fit for short range communication. In short range, the pulse extension due to scattering is at microsecond order and its influence for low and moderate bit rate communication systems is weak. Since the light output power of a single ultraviolet LED is low, a multi-LED array can be used to increase the transmit power and extend the communication range.

仿真分析与实验结果显示：日盲区紫外光在大气中散射传输时由于大气粒子的强烈散射与吸收，传输损耗较大，距离每增加10倍，接收功率下降20dB，因此日盲区紫外光大气散射通信适用于近距离通信场合；近距离传输时散射造成的光脉冲多径展宽为微秒量级，对中低速通信系统影响较小；单个紫外LED发光功率较低，可通过多个LED阵列来提高发射功率，增大通信距离。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。