正弦脉冲与等腰梯形脉冲传播特性的比较

The Comparison of Axial Energy?s Decaying Property Between Sine and Isosceles Trapezium Electromagnetic Wave Pulse

研究了正弦脉冲中正弦波的周期T1与等腰梯形脉冲中等腰梯形波的中心频率相等,且具有相同的总脉冲周期T时,对相同圆形单元辐射器的轴线能量传播特性,解析与计算机数字模拟结果表明:当等腰梯形脉冲的上升时间小于中心频率的1/20时,在等腰梯形脉冲传播的慢衰减区,其传播特性优于对应的正弦脉冲的传播特性;当一次正弦脉冲中包含的正弦波数数目k远大于1时,不同k值的正弦脉冲具有相同的慢衰减特性。

Assuming the cycle T1 of sine wave of the sine electromagnetic wave pulse is equal to the central frequency of the isosceles wave of the isosceles trapezium electromagnetic wave pulse and both have same general pulse cycle T. Studying the axial energy抯 decaying property of the two waveforms on the same circular radiation antenna through the analytical and computer digital simulation, the results indicate: (1) In the slow decaying area of the isosceles trapezium electromagnetic wave pulse抯 propagation, when the rising time of isosceles trapezium waveform is less than one twentieth of the sine waveform抯 period, the axial energy抯 decaying property of isosceles trapezium electromagnetic wave pulse is better than that of sine electromagnetic wave pulse; (2) If k, the number of sine waveforms contained in one sine electromagnetic wave pulse, is far larger than 1, the sine electromagnetic wave pulse, no matter what different value of k, will have same decaying property.