Radiating beyond the bandwidth using direct antenna modulation

A broadband transmitter design concept is proposed based on an antenna's nonlinear transient responses when integrated with switching devices. The switches are placed on special locations on the anttenna so that they are able to shut off and turn on the antenna's radiation slots in real time to produce the radiation of narrow pulses. The resonant antenna's bandpass phenomenon, which limits the antenna's bandwidth and further the system bandwidth, can be overcome. Experimental results show that a patch antenna with a resonant frequency of 2.4 GHz and a 30 MHz bandwidth can transmit a digital modulated signal with more than 400 MHz bandwidth.