| Terahertz wave has good application prospects in many fields such as imaging,communication and security due to its rich spectrum resources.It has become a research hotspot in academic and industry in recent years,thus the research on terahertz technology and related circuit technology has great significance.This thesis studies and designs super regenerative receivers for terahertz imaging applications.First,the thesis introduces the terahertz frequency spectrum,the basic characteristics of the terahertz wave,and its related applications.The research status of domestic and foreign terahertz transceivers in recent years is summarized,and theoretical analysis of terahertz super regenerative receivers and related modules are performed.Based on this,design of three circuits such as the 297.4 GHz voltage-controlled oscillator,280 GHz super regenerative receiver,280 GHz fully integrated charge-accumulation super regenerative receiver are completed.The main research contents and contributions of the thesis are as follows:(1)In order to improve the sensitivity of super regenerative receivers,considering the relevant loss mechanisms of silicon-based CMOS,a differential parallel inductor is proposed,which can improve the quality factor and further improve the sensitivity of super regenerative receivers.The differential parallel inductor was used to complete the design of an oscillator.As one of the core circuit units of a super regenerative receiver,the oscillator operates at a frequency of 295.6~299.7 GHz,a frequency tuning range of 4.1 GHz,and a phase noise of-106.7d Bc/Hz at 10 MHz frequency offset.When the 1.2V power supply is used,the power consumption is 20.8mW.(2)On the former research basis,a super regenerative receiver with a center operating frequency of 280 GHz and a sensitivity of-90 d Bm has been studied and designed based on 65 nm CMOS process(has been successfully taped out and is currently under test).The post simulation results show that at 281.5 GHz,when the input signal is-20 d Bm,the receiver has a maximum gain of 16.5 d B,an operating bandwidth of 2.3 GHz,and a power consumption of 10.8mW at a 1.2 V supply voltage.(3)In order to reduce the problems of complex interconnect processing between the off-chip antenna and circuit in the terahertz band,the impedance matching between the antenna and the circuit,and the large loss introduced by the impedance matching of the signal input port in the circuit,the thesis designed an antenna-integrated charge accumulation super regenerative.By using the impedance of the receiver signal input point as the load impedance to complete the design of an on-chip antenna,while increasing the flexibility of the circuit design,it effectively improves the process and loss problem caused by the off-chip antenna and circuit interconnection.The center frequency of antenna designed in this thesis is 280 GHz,the gain is-1.9d B,the directivity coefficient is 7.2d B,and the radiation efficiency is 12.2%.The maximum gain of the fully integrated super regenerative receiver integrated with on-chip antenna is 36.1 d B at 280 GHz.The gain over 35 d B in the 278 GHz ~ 282 GHz range,with good gain flatness.The sensitivity is-88 d Bm,operating bandwidth is 6.1GHz and power consumption is 17.7mW at 1.2V supply voltage. |
