调频合成

基于CORDIC算法的线性调频直接数字合成实现

A CORDIC-Based LFM Implementation in Direct Digital Synthesizing

本文介绍了一种应用CORDIC算法的线性调频直接数字合成（DDS）的实现方法。

A new method LFM in direct digital frequency synthesizing ( DDS ) based on CORDIC algorithm is introduced in this paper .

运动补偿问题是制约机载调频连续波合成孔径雷达（FMCWSAR）实现超高分辨率成像的瓶颈。

The combination of frequency modulated continuous wave ( FMCW ) technology and synthetic aperture radar ( SAR ) techniques is often used to obtain ultra-high resolution .

针对大面积分布目标的回波模拟需要大量运算，依据调频连续波合成孔径雷达回波结构的特点，提出了一种基于FFT的快速回波模拟算法，与直接点目标求和方法相比运算量大大缩减。

According to the echo structure of FM-CW SAR , a fast algorithm for echo simulation of distributed targets based on FFT is presented , reducing the computation significantly comparing with one by one point superposition .

因此调频信号的合成就成为了其中关键性的一项技术。

The synthesis of FM signals is reasonably regarded as one sort of key technique .

基于时域信号模型，本文对调频连续波合成孔径雷达的回波进行了模拟。

According to the signal model , this paper simulates the echo of FM-CW SAR .

调频连续波合成孔径雷达可以实现小型化，能非常好地满足轻型飞行平台对成像设备的要求。

Frequency modulated continuous wave synthetic aperture radar ( FM-CW SAR ) can be miniaturized , and it is fit for light-duty flight platform wonderfully .

为解决用于直接模拟式频率综合器、锁相式频率综合器跳频时间测试方法的不足，提出了一种用调频控制器、合成信号源混频器和示波器等进行测试的改进方法。

To improve the disadvantages in the hopping time measurement of digital analog frequency synthesizer and frequency-locked frequency synthesizer , a modified measurement method by using of frequency-modulated controller , synthetic signal source mixer and oscilloscope was put forward in this paper .

线性调频信号DDS频率合成源的设计与实现

Development of DDS Digital Synthetic Frequency for Chirp Signal Generation

理想情况下，SAR回波多普勒信号是线性调频信号，采用合成孔径原理提高方位向成像分辨率。

In ideal circumstances , the back scattered echo signal of SAR is chirp signal . With synthetic aperture theory , high azimuth resolution imaging to distant targets can be attained .

线性调频法是逆合成孔径雷达（ISAR）成像中一种常用的方法，在该方法中扫频非线性对成像质量有一定的影响。

LFM is one of widely used methods of ISAR . Nonlinearity in frequency sweep has some effects on the quality of imaging .

变线性调频斜率符号在合成孔径雷达中的应用

Application of Changing Chirp Rate Sign in Eliminating Range Blur of SAR

一种数字调频系统专用频率合成芯片的设计

Design of PLL Frequency Synthesizer for Digital Tuning System

复杂调频信号的数字合成及误差分析的研究

The research of digital synthesis and error analysis of a complex FM signal

调频信号的数字合成方法

The Method of Digital Synthesis of FM Signals

基于α稳定分布自共变的雷达回波频率谱估计变线性调频斜率符号在合成孔径雷达中的应用

Radar echo frequency spectrum estimation based on α stable distribution covariation Application of Changing Chirp Rate Sign in Eliminating Range Blur of SAR

应用该算法可以处理脉冲压缩后的回波信号，而且在进行距离单元迁移校正的过程中不依赖于线性调频特性，故可以应用于处理非线性调频合成孔径雷达信号。

This improved CZT imaging algorithm can process range compressed signals and the RCM compensation is independent of linear frequency modulation ( LFM ) characteristic of LFM signals .