K波段汽车防撞雷达信号源的设计与实现

Abstract硕士论文AbstractAs the tremendous progress in human industrial civilization and the rapidgrowth of the economy,car has become a kind of necessary vehicle in daily life.Butthe car has also caused many traffic accidents,which have become a very seriousproblem in our society.Automotive collision avoidance radar allows car drivers knowthe distance and speed of surrounding vehicles and it also can alert the driver at thecrucial moment,and then avoid the occurrence of the accident.Meanwhile,thisradar can also bring huge economic value.Therefore developing automotive collisionavoidance radar has very important significance and widely applications.Now inChina the automotive collision avoidance radar research is lack of the corecomponents -the signal source,this paper is written for this situation and it thenimprove the traditional anti-collision radar transmitted waveform,complete thedesign of key components of the signal source PLL and DDS.The main work can becarried out as follows:First,I discuss traditional transmitted waveform and insert period pointfrequency in triangle-wave modulation for matching a plurality of target detection.Improved transmitted waveform has less difficulty in hardware and more simpledigital signal processing.Then,this paper raises several engineering means.After comparing eachtechnique's phase noise,spurious,FM linearity we find that the means of DDSmixer on K-band carrier frequency is the best one.In order to meet the needs of thecollision avoidance radar ranging and its using environment,we carefully calculateand decide PLL and DDS Design specifications.Finally,the paper analyzes the general principle of the PLL and DDS.Afterchoosing appropriate components and software simulation,we successfully designed24GHz PLL and triangle-wave modulation DDS.The test indicates that the 24GHzPLL output power is 10dBm,and its phase noise is better than-75dBc@1KHz,-73dBc10KHz,that the DDS sweep output for 150MHz-250MHz with insert pointfrequency of 125MHz.The DDS's output power flatness is less than 0.5dB,and theproximal and distal spurious second harmonic suppression is greater than 65dB,itsphase noise is better than -96dBc 10KHz.Keywords:anti-collision radar signal source PLL DDS