【摘要】 基于直接数字频率合成(DDS)技术在带宽、频率转换速率、调频线性度、频率分辨率和稳定度等方面的优异性能,提出了采用直接数字频率合成芯片AD9854来设计雷达线性调频信号产生系统的一种方案,该方案用PC机控制雷达波形参数,频率转换时间最低可以达到10ns,输出频率范围4~10MHz,扫频带宽3~100kHz,扫描时间10~1000ms,输出线性调频信号无杂散动态范围(SFDR)优于70dB,经实验验证,该系统可以满足高频地波雷达发射和接收系统的要求.更多还原

【Abstract】 Based on the high performance of DDS in radar waveform synthesis,the DDS chip AD9854 is used in designing the radar waveform generator. This method has more advantages in the bandwidth,chirp rate,flexibility than that made up of traditional frequency synthesis based on VCO. The output frequency band is 4-10 MHz,and sweep band is 3-100 kHz,and sweep time is 10-1000 ms,and SNR exceeds 70 dB. This radar waveform generator satisfies the requirement of high frequency ground wave radar.更多还原