调频技术在降低电磁发射中的应用

摘要

The frequency modulation techniques can,according to certain rule,spread energy of certain frequency to a cer⁃tain bandwidth,and accordingly reduce peak power. However,the bandwidth of measuring receiver is invariable,if the spread frequency bandwidth is bigger than the using bandwidth of measuring receiver,the measuring receiver can not receive all ener⁃gy,so the peak power of electromagnetic emission is reduced. By comparing the ideal reduced values and real measured values at different modulation frequency and modulation depth,the result show that the value of electromagnetic emission is affected by modulation frequency,modulation depth and measuring bandwidth.%　　调频技术可以将某个频率的能量按一定规律扩展到一定的带宽内，从而降低了峰值功率，而测试接收机的带宽是固定的，如果扩展频谱的带宽大于测试接收机所使用的带宽，测试接收机不能接收全部能量，降低了电磁辐射发射峰值功率。对比在不同调制频率和调制深度下的理论降低值和实测降低值，表明电磁发射降低的值受调制频率、调制深度和测量带宽的影响。