Research And Design Of Key Technologies Of Millimeter-wave And Submillimeter-wave Radar Receiver Front-end

With the development of the fourth industrial revolution,advanced radar systems have become a more and more important part of the Internet of Things,which have very broad application prospects,especially in the field of outdoor autonomous driving,indoor intelligent medical care,and industrial quality control.Radars are playing an increasingly indispensable role.Among them,millimeter wave automotive radar and submillimeter wave imaging radar have become an indispensable part due to their strong anti-interference,low cost and high accuracy.Therefore,this article completes a77 GHz robust phased array radar receiving front-end design for long-distance vehicle detection,and also finishes one single channel of a 250-400 GHz pipelined,frequencyinterleaved radar transceiver front end for high-precision imaging.The main tasks are as follows:For the 77 GHz phased array automotive radar receiving front-end: we firstly conducted pilot research on the key modules,the low-noise amplifier(LNA)and phase shifter(PS).Based on the 55 nm CMOS process,the design and testing of three chips,the high linearity LNA 1,the large bandwidth LNA 2,and the 5-bit phase shifter,have been completed.For the low-noise amplifier(LNA),the out-of-phase dual-coupling gm-boosting technique is implied to achieve high gain and low noise figure.In order to further improve the performance of the proposed LNA,the inductive feedback common-gate-shorting technique with capacitance elimination are introduced.What's more,the active resonance peaking control technique is proposed to achieve a flat gain to extend the bandwidth.The measurement results indicate that the LNA1 achieves a small signal gain of 17.1 d B,a BW-3d B of 74.8?88.8 GHz,a NF of 6.3 d B as well as an input-referred 1d B compression point of-10.2 d Bm.The LNA2 achieves a peak gain of 11 d B with a gain variation of less than 0.5 d B,a BW-3d B of 62.7?85.9 GHz,a NF of 7.7 d B as well as an IP1 d B of-5.4 d Bm.The measurement results indicate that the phase shifter achieves a rms phase error between 3.5° and 7.3°.Based on the LNA and PS design strategies and measurement results above,we further completed the design of the entire 77 GHz high robust phased array automotive radar receiving front-end.For the purpose of PCB testing and good yield,the influence of bonding wires and process corner deviations are considered.First,the S2 P results of bonding wires are bring in low-noise amplifiers for joint design of noise matching and impedance matching.Then we use resonance peak control technology to realize a broadband amplifier for eliminating the effect of the process corner deviations.In the phase shifter,the tail tuning network is used to resist the effect of the process corner deviations.The post simulation results show that the overall power consumption of the entire eight-channel receiver is 420 m W.For the TT40°C process corner,the peak gain of one single channel can achieve 18.6 d B,the 3 d B bandwidth covers the range of 76-81 GHz,and the IP1 d B is better than-19.4 d Bm,The minimal noise figure is 7.7 d B.The pattern shows that the receiver can achieve a peak-to-null greater than 20 d B,a peak-to-peak greater than 10 d B,and a 3 d B beamwidth of 8°.For the 250-400 GHz time-domain pipeline and frequency interleaved imaging radar transceiver front-end: We completed the layout and post-simulation of the channel switch module and one single channel of this transceiver(287.5-306.25 GHz).Aiming at the two design difficulties of how to smoothly switch between channels and how to share antennas for transmitter and receiver.We realize a reconfigurable Wilkinson power divider with a gain flatness of 1.5 d B for channel switching.The front end of the transceiver includes a six-folder chain,a doubler,a mixer and baseband amplifier.This article focuses on how to use load-pull and input network of mixer for joint design of doubler and mixer to achieve a trade-off between noise figure and output power.In the end,the single channel achieved an optimal NF of 19 d B at a power consumption of109.8 m W,an IP1 d B of-1.5 d Bm,and an output power of-3.2 to-0.7 d Bm.