通信系统

Discrete Walsh functions is an kind of orthogonal functions with +1 and –1 only.

因此实现CDMA通信系统的关键技术之一就是要找到一组正交性能优良的地址码。

In the new system, the orthogonal functions replace the trigonometric functions in the coherent modulation-demodulation of traditional communication system.

正是这种正交函数使得通信系统的传输的性能大大提高，保密性加强，而且正交函数的产生很方便。

The paper presents a new orthogonal sequence modulation sceheme using FHT which is easier to implement than FFT.

在宽带移动通信系统中，经常考虑采用通过FFT实现的多载波调制，如OFDM。

Multipath is the main character of the mobile communication system. Multipath signal of the target user turn out to be the ISI of the main path signal, multipath signal of the other users cause severe MAI since the orthonormality among the spreading codes is destroyed.

多径干扰是移动通信系统中的常见干扰，目标用户的多径信号对主路径信号引入了码间干扰，其它用户的非同步路径信号由于破坏了扩频序列的正交特性而导致了强的多址干扰。

A new parallel high level data link controller was designed using the hardware description language on the FPGA device. The HDLC protocol controller can construct or deconstruct the multi-channel HDLC protocol frames in parallel way. As a result, it improved the robust and reliability of the whole system.

在FPGA内部采用硬件描述语言并行设计多通道的高级数据链路控制协议控制器，该协议控制器有效利用FPGA的片内硬件资源，实现了并行解析和生成多通道的HDLC协议报文，提高了数据通信系统中的多通道扩展性、实时性和稳定性。

Noise is measured at one or more base stations in a mobile communication system during periodic silence periods.

在周期性无声期期间在移动通信系统中的一个或更多基站上测量噪声。

The microwave power amplifier is the key component in communication system.

微波功率放大器是通信系统中的关键器件。

This paper mainly deal with the sink of the spread spectrum communication on power line.

本文主要负责电力线扩频通信系统的接收部分。

This invention discloses a user data process method, which contains 1, judging each data package in IP data steam sent form high layer of empty command protocol stack, if the received IP data package is TCP ACK data package, then executing step 2, if the received data package is not TCP ACK, then executing step 3, 2, making PDCP layer function process to IP data package and ending current process, 3, making flow control to IP data package and then executing 2,, said invention can precedential send TCP ACK data package to opposite part in preserving original TCP/IP and universal mobile telecommunication system data transmission system base, to reduce data package reversion time delay and keep stable data transmission rate.

本发明公开了一种用户面数据处理方法，其主要处理步骤如下：a。对从空口协议栈中高层下发的IP数据流中的每一个数据包进行判断：当前接收到的IP数据包是否为TCP的ACK数据包，对所有是TCP的ACK数据包的IP数据包执行步骤b；对所有不是TCP的ACK数据包的IP数据包执行步骤c；b。对IP数据包进行PDCP层的功能处理，结束当前处理流程；c。对IP数据包进行流控，再转入步骤b。采用本发明方法能够在保持原有TCP/IP和全球移动通信系统数据传输机制的基础上，优先将TCP的ACK数据包发送到对方，从而减少TCP的ACK数据包的回复时延，保证稳定的用户面数据传输速率。

In this thesis, we are working on some main techniques used in OCDMA system based on some of the precedents\' research works.

本论文试图在前人工作的基础上，对OCDMA通信系统中的一些关键技术问题进行探讨。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。