There are numerous applications, such as Radar, that leverage wideband technology. However, the presence of noise introduces certain limitations and challenges. It is crucial to harness wideband technology for applica...There are numerous applications, such as Radar, that leverage wideband technology. However, the presence of noise introduces certain limitations and challenges. It is crucial to harness wideband technology for applications demanding the rapid and precise transmission of diverse information from one point to another within a short timeframe. The ability to report a signal without tuning within the input bandwidth stands out as one of the advantages of employing a digital wideband receiver. As indicated, a digital wideband receiver plays a pivotal role in achieving high precision and accuracy. The primary distinction between Analog and Digital Instantaneous Frequency Measurement lies in the fact that analog Instantaneous Frequency Measurement (IFM) receivers have traditionally covered extensive input bandwidths, reporting one accurate frequency per short pulse. In the contemporary landscape, digital IFM systems utilize high-sampling-rate Analog-to-Digital Converters (ADC) along with Hilbert transforms to generate two output channels featuring a 90-degree phase shift. This paper explores the improvement of sensitivity in current digital IFM receivers. The optimization efforts target the Hilbert transform and autocorrelations architectures, aiming to refine the system’s ability to report fine frequencies within a noisy wide bandwidth environment, thereby elevating its overall sensitivity.展开更多
瞬时测频(instantaneous frequency measurement,IFM)接收机是电子侦察中非常重要的测频资源,其结构简单、灵敏度高、侦察频带宽、分辨率高,可以快速测定被测信号的频率,在现代电子战中得到广泛应用。基于IFM微波鉴相器在某一瞬间只能...瞬时测频(instantaneous frequency measurement,IFM)接收机是电子侦察中非常重要的测频资源,其结构简单、灵敏度高、侦察频带宽、分辨率高,可以快速测定被测信号的频率,在现代电子战中得到广泛应用。基于IFM微波鉴相器在某一瞬间只能响应一个信号的特性,结合IFM工作原理,研究了一种新的(超过2个信号)对IFM干扰策略,并分析了干扰机理,通过模拟仿真对IFM的干扰效果进行了评估。仿真结果表明:多信号交叠可以对IFM系统产生明显的干扰效果,可以使得其无法测得正确频率,并错误地输出同时到达信号指示。展开更多
RWR/ESM系统多采用传统的瞬时测频(instantaneous frequency measure,IFM)技术实时检测信号频率,但这种测频技术对交叠信号只能估计一个信号的频率,且容易产生测频错误。现代战场中电磁环境异常复杂,脉冲交叠概率越来越高,因此研究交叠...RWR/ESM系统多采用传统的瞬时测频(instantaneous frequency measure,IFM)技术实时检测信号频率,但这种测频技术对交叠信号只能估计一个信号的频率,且容易产生测频错误。现代战场中电磁环境异常复杂,脉冲交叠概率越来越高,因此研究交叠信号对IFM系统的影响尤显重要。为此根据IFM原理,分析了双交叠信号情况下IFM微波鉴相器的各节点响应,并建立了输出UI,UQ的数学模型,提出一种估计双交叠信号频率的算法—UI,UQ推算法。仿真结果表明:该算法能够在保持原有IFM优点的情况下,估计2个交叠信号的频率。展开更多
文摘There are numerous applications, such as Radar, that leverage wideband technology. However, the presence of noise introduces certain limitations and challenges. It is crucial to harness wideband technology for applications demanding the rapid and precise transmission of diverse information from one point to another within a short timeframe. The ability to report a signal without tuning within the input bandwidth stands out as one of the advantages of employing a digital wideband receiver. As indicated, a digital wideband receiver plays a pivotal role in achieving high precision and accuracy. The primary distinction between Analog and Digital Instantaneous Frequency Measurement lies in the fact that analog Instantaneous Frequency Measurement (IFM) receivers have traditionally covered extensive input bandwidths, reporting one accurate frequency per short pulse. In the contemporary landscape, digital IFM systems utilize high-sampling-rate Analog-to-Digital Converters (ADC) along with Hilbert transforms to generate two output channels featuring a 90-degree phase shift. This paper explores the improvement of sensitivity in current digital IFM receivers. The optimization efforts target the Hilbert transform and autocorrelations architectures, aiming to refine the system’s ability to report fine frequencies within a noisy wide bandwidth environment, thereby elevating its overall sensitivity.
文摘瞬时测频(instantaneous frequency measurement,IFM)接收机是电子侦察中非常重要的测频资源,其结构简单、灵敏度高、侦察频带宽、分辨率高,可以快速测定被测信号的频率,在现代电子战中得到广泛应用。基于IFM微波鉴相器在某一瞬间只能响应一个信号的特性,结合IFM工作原理,研究了一种新的(超过2个信号)对IFM干扰策略,并分析了干扰机理,通过模拟仿真对IFM的干扰效果进行了评估。仿真结果表明:多信号交叠可以对IFM系统产生明显的干扰效果,可以使得其无法测得正确频率,并错误地输出同时到达信号指示。
文摘RWR/ESM系统多采用传统的瞬时测频(instantaneous frequency measure,IFM)技术实时检测信号频率,但这种测频技术对交叠信号只能估计一个信号的频率,且容易产生测频错误。现代战场中电磁环境异常复杂,脉冲交叠概率越来越高,因此研究交叠信号对IFM系统的影响尤显重要。为此根据IFM原理,分析了双交叠信号情况下IFM微波鉴相器的各节点响应,并建立了输出UI,UQ的数学模型,提出一种估计双交叠信号频率的算法—UI,UQ推算法。仿真结果表明:该算法能够在保持原有IFM优点的情况下,估计2个交叠信号的频率。
文摘提出了一种基于时间戳计数的IFM算法.对基准时钟进行频率倍频和等时延多路移相处理,在测量周期内对被测信号fx以及多路基准时钟并行的连续计数,采用回归分析统计方法对这2组计数值进行计算得到fx频率值.对测量误差进行了分析,实验及对比测试数据表明,该方法在同样的测量条件下能够有效地减小由传统计数测频法中±1量化误差引入的测量误差.能够提高测量分辨率约2～3个数量级,测量误差减少30％以上,测量处理时间优于200 ns.
