论文标题
带有时间周期和空格均匀调制的电匹配天线
Electrically small matched antennas with time-periodic and space-uniform modulation
论文作者
论文摘要
一种概念性方法，可以使用仅在时间上调制的传输线来讨论阻抗匹配的电天线。 Varcapacitor的分布式分流阵列的时间周期性空间均匀调制激发了一种非常小的频率模式，但仍然是一个小（微波）波长：匹配线然后保留了实用的大小。调制传输线将阻抗匹配的问题带到频率$ f_0 $的频率比信号高得多的频率$ f_0 $，在同一$ q $ factor中，很容易用更高的带宽来补偿大型天线电抗：实际上，当$ΔF= f_0 / q $ f _0 $ f_0时，带宽$ΔF= f_0 / q $比信号频率大得多。说明了获取传输线的空间均匀调制的一种简单方法，使用了调制式静脉曲张的惠斯通桥的布置。信号和调节线在相同长度的一部分上并联运行，请参见两个非常不同的等效分流电容，因此调制电压几乎是均匀的，而信号电压可能会在整个传输线上发生显着变化。
A conceptual method to realize an impedance-matched electrically small antenna is discussed, using a transmission line modulated only in time. The time-periodic space-uniform modulation of a distributed shunt array of varcapacitors excites a mode with very small frequency but still a small (microwave) wavelength: the matching line then retains a practical size. The modulated transmission line brings the problem of impedance matching to a frequency $f_0$ much higher than the signal, where the large antenna reactance can be easily compensated with a much higher bandwidth for the same $Q$ factor: actually the bandwidth $Δf= f_0 / Q$ becomes large when $f_0$ is much larger than the signal frequency. A simple way to obtain the space uniform modulation of the transmission line is illustrated, making use of a Wheatstone-bridge arrangement of the modulated varicaps. The signal and modulating lines, running in parallel on a section of the same length, see two very different equivalent shunt capacitances, so that the modulating voltage is almost uniform while the signal voltage may change significantly across the transmission line.
