Circuit Design Of CMOS Terahertz Oscillation Source With Tuning Function

As the impact of wireless communication on people's lives is gradually increasing,the bandwidth requirements of communication systems are becoming more demanding.Due to the shortage of spectrum resources and the limited channel transmission rate,it is currently difficult for lower spectrum to meet the design requirements.The development of wireless communication for higher frequency bands has become an inevitable trend.Terahertz waves,as electromagnetic waves greater than 100 GHz,are still the focus of research mainly because of short wavelengths and wide frequency bands.Therefore,the performance of the terahertz oscillation source directly affects the quality of the communication system,which is an important content in the terahertz wave field.This article first describes the background and research significance of the terahertz wave,and investigates the current research progress and main difficulties of the terahertz oscillator circuits.Next,the basic knowledge of the terahertz oscillator is systematically introduced,including the circuit structure,performance parameters and related terahertz devices.In the circuit design,the overall circuit structure is selected according to the design indicators.Then the Colpitts oscillator and the Colpitts oscillator coupling circuit are researched and designed separately,and the second harmonic power of the oscillation is extracted by the second harmonic extraction technology to optimize the performance of the output signal performance.Finally,a260 GHz terahertz oscillation source circuit is composed of a loop including eight interconnected Colpitts units and the frequency tuning range is improved by using varactor and injection-locked tuning.The grounded coplanar waveguide(GCPW)transmission line is designed and optimized by EM simulation.The layout design and simulation are completed on 40 nm CMOS process platform.The post-simulation results show that when the supply voltage is 0.9V and the free oscillation frequency is261.6 GHz.With the control voltage changing from-1 to 1 V,the output signal frequency range is 257.1 ? 266 GHz,achieving 3.4% tuning range,the output power range is-3.3 d Bm ?-30 d Bm,the phase noise is-91 ?-79 d Bc / Hz @ 1MHz and the overall circuit power consumption is 127 mW.Finally,the test plan of the chip is given.