变频模块

基于PCI总线的数字下变频模块设计

Design of Digital Down Converter Module Based on PCI Bus

此硬件平台由天线阵列、射频前端接收模块、FPGA中频数字下变频模块、PC机四部分组成。

The hardware platform consists of antenna arrays , RF front-end receiver module , FPGA IF-digital down converter modules , and PC machine .

介绍了一种应用于GHz级高速频率合成器的数模混合下变频模块。

An optimized method is presented to design the down scalers in a GHz frequency synthesizer .

为了达到高集成度，减少芯片资源占有率，本文采用了CORDIC算法实现可编程下变频模块，减少了乘法器和查找表的使用。

In order to achieve high integration and reduce chip resources share , the CORDIC algorithm was used to implement programmable digital down converter module which reduced the use of multiplier and look-up table .

设计并用芯片实现了一个QAM的解调系统，该系统涉及下变频模块、A／D模块、码元时钟恢复模块、载波恢复模块和自适应均衡模块、前端纠错模块等。

In this paper , a QAM demodulation system is discussed and an IC implementation is presented . The system includes down-convert module , A / D module , timing and carrier recovery module , equalizer and FEC module , etc.

实际制作的下变频模块变频增益为30dB±1dB，噪声系数小于7.5dB，镜像抑制大于110dB。

A conversion gain of 30 dB ± 1 dB , a noise figure of less than 7.5 dB and an image rejection of more than 110 dB have been achieved over the RF frequency range .

空时抗干扰系统中A/D采样和数字下变频模块的设计与实现

ADC Application & DDC Design in Spatial-temporal Anti-jamming System

该系统涉及下变频模块，A/D模块，码元时钟恢复模块，载波恢复模块和自适应均衡模块，前端纠错模块等。

The system includes down-convert module , A / D module , timing and carrier recovery module , equalizer and FEC module .

下变频模块的功能是将接收到的3.4~4.2GHz射频信号下变频到0.95~1.75GHz的中频信号。

The down-conversion module receives RF signals between 3.4 GHz and 4.2 GHz and converts them down to IF frequency between 0.95 GHz and 1.75 GHz .

第三章探讨虚拟无线电试验系统底层硬件的结构设计，包括数字上变频模块和数字下变频模块。

In the third chapter the structure design of the bottom hardware layer of virtual radio experiment system was discussed , including digital up-converter and down-converter module .

最后，对所设计的扫描变频模块和信号采集处理模块进行了测试，并且对测试的结果做了讨论。

Finally , the design of the scanning frequency of the signal acquisition and processing module and the module was tested and the results of the test were discussed .

多联空调机组控制系统是将变频模块、变频压缩机和制冷系统有机集成一体的控制单元，其技术核心是变频控制模块。

The control system of multi-connected air-condition unit is the control unit which combines a variable frequency module , a variable frequency motor of compressor and a system of refrigeration .

芯片主要由发射机和接收机两大部分组成，发射机主要包括编码模块、数字调制器模块，以及数字滤波模块等；接收机主要包括数字下变频模块、数字解调器模块、解码模块等。

The transmitter includes coding module , digital modulation module , and digital filtering module and so on ; the receiver includes digital down-conversion module , digital demodulation module , decoding module .

实验结果表明，扫描变频模块和信号采集处理模块均能够正常工作，从而可以满足强背景噪声下未知的多频点的微弱信号检测的要求。

The results showing that scan conversion module and the signal acquisition and processing module are able to meet the extraction of the the unknown multi-frequency weak signal from strong background noise .

其特征是：所述壳体（3）中还设有变频模块（6）和三相变频电机（7）；

The utility model has the characteristics that : the shell ( 3 ) is also provided with a frequency conversion module ( 6 ) and a three-phase frequency conversion motor ( 7 );

硬件的设计以符合现场的功能和性能要求为原则，采用模块化设计，主要包括主控器模块、温度检测模块、A/D转换模块和变频模块。

The hardware design to meet the functional requirements and performance of the site for the principle , modular design , including the control device module , temperature detection module , A / D conversion module and frequency conversion module .

运用自顶向下和自底向上的思想完成了数据读取控制、PI调节、串行通讯、变频等模块的设计，并给出了软件实现图及仿真时序图。

The data reading control module , PI control module , serial communication module , variable-frequency control module , and so on , have been realized by using top-down design and down-top idea . The software implement and timing simulation figures are shown in this paper .

软件无线电数字下变频组成模块的研究与分析

Research and Analysis on the Digital Down Down Converter Modules of the Software Radio

结合本次系统的指标要求，给出了上变频发射模块的设计与具体的硬件实现。

Based on system specification , the design and hardware realization is given for transmitter up-converter .

硬件模块包括：信号采集模块、数据采集卡、信号调理模块、变频控制模块以及PC机等。

Hardware module include signal acquisition module , data acquisition card , signal conditioning module , frequency conversion control module and PC machine .

外接信号调理板、步进电机驱动模块、主轴变频调速模块、I／O模块等构成硬件总体结构。

Circumscribing the signal adjustment plate , stepping motor drive mold piece , spindle inverter mold piece and I / O mold piece constitute the total hardware construction .

变频空调PFC模块的研究

Research on the Variable Frequency Air - conditioner PFC Module

介绍了数字电视地面广播（DVB-T）发射端的原理，给出了基于FPGA的实现方案，重点阐述了信道编码、OFDM调制、数字上变频三个模块的设计。

In this article , the principle of transmitter of DVB-T system is introduced first , and the implementation scheme based on FPGA platform is given . Finally , we emphasize the design of three key units such as channel coding , OFDM modulation and digital upconverter .

在实时软件编制方面，利用汇编语言和16位定点C语言混合编程的方法，编写了变频调速系统的模块化程序，以便于修改和移植。

On the side of real time software , the module software is written by assembly language functions that interface with 16 bits fixed-point C code so that it can be amended and replanted easily .

在变频产品开发中，通过变频模块产生的PWM信号，在控制直流无刷电机中，会产生严重的电磁噪声，将影响电磁兼容测试中的指标。

In inverter product system , electromagnetic noise produced by PWM amplifier signal from the inverter module in control system of DC motor with non-brush can effect the levels of voltage conducting and power radiation .

变频减速一体机是将变频模块、变频电机和减速机有机集成一体的重要传动控制单元。

An integrating device of variable frequency and speed-down is an important driving and control unit which combines a variable frequency module , a variable frequency motor and a retarder .

该电路采用二次变频低中频结构，集成了低噪声放大器、上变频混频器、下变频混频器等模块。

An RF front-end circuit for a fully integrated CMOS DTV tuner is presented in this paper , where double-conversion low IF architecture is employed .