The X(-Band) Files: An X-Band Microstrip Voltage-Controlled Oscillator with Wideband Tuning Range

Signal sources are essential devices for radar and communication systems. The demand for oscillators has existed for very long time. In 1888, Heinrich Hertz introduced the first known oscillator to prove Maxwell's equations experimentally [1]. He used a dipole as the frequency determining structure and a spark-gap generator as the signal source. His invention signaled the birth of wireless communications because Hertz confirmed the existence of electromagnetic radiation which was postulated by Michael Faraday and James Clerk Maxwell.