two-wire carrier system

This paper introduces the architecture of DVB_C system and basic theory of QAM modulation and demodulation at first, analyzing and discussing two ways to implement the initial demodulator: simple sequencer and generating native carrier to demodulate.

本文介绍了DVB-C系统的结构和QAM调制解调的基本原理及其系统结构；分析比较了初始解调电路的两种实现方式：产生本地载波进行解调和简单序列解调。

Based on the three-dimensional servo tracking system of carrier-based satellite antenna, the azimuth angle, elevation angle, and polarization angle of antenna were controlled through two-dimensional motor driver mechanism.

基于舰载卫星天线三维伺服跟踪系统，通过二维电机驱动机制控制天线方位角、俯仰角和极化角。

Based on the rate equations of two-level system, the solutions of spin-up and spin-down carrier populations are obtained under the condition of incompletely initial spin polarization photoinduced by elliptically polarized pump light.

基于二能级体系的速率方程，获得了椭圆偏振光泵浦注入非完全自旋极化初始条件下的自旋向上和向下载流子布居的解析解。

Custom communications system, through an agreement with the carrier detect achieve the two-way synchronous communication.

系统通过自定义通信协议,实现带有载波侦测的 双向 同步通信.

According to the sample information security requirements of material intelligent system, analysis of the commonly used two-dimensional bar code character, determined the design plan which using QR two-dimension bar code as a power plant sensitive information carrier.

论文所做的主要工作有：1.根据物料智能采制系统中样品信息安全性需求，分析了常用的二维条码的特性，确定了选择QR二维条码作为电厂敏感信息的载体的设计方案。