Design Of Ultra-wideband CMOS Multi-way Power Combiner/Divider

Power divider is an indispensable part of microwave receiving,transmitting and frequency synthesizing system,which is widely used in phased array radar,multi-channel relay communication machine and other microwave equipment.Traditional passive power divider based on transmission lines often unable to meet the requirements of size and performance.With the development of CMOS technology,the development bottleneck of the system-on-chip has been broken.The power divider realized by CMOS technology can greatly reduce the size and meet the design requirements of low loss and high integration.Based on the technology of SMIC 40 nm CMOS,the ultra-wideband CMOS multi-way power divider is studied and designed innovatively in this thesis,and the complete design process is proposed.The main contents of this thesis are as follows:Firstly,the ultra-wideband CMOS passive power divider is designed.By the analysis of lumped parameter transmission line theory,two port network,ABCD matrix and impedance matching network,LC matching network is used to replace the traditional one quarter wave transmission line,and finally the structures of the two-way,the four-way and the eight-way power dividers circuits are designed.In addition,the simulation test of S-parameters is carried out,and the results show that the bandwidth,isolation and insertion loss meet the design requirements.Among them,the operating frequency ranges of both the two-way and the four-way power dividers are 10GHz-32 GHz,and the operating frequency range of the eight-way power divider is about 10.4GHz-30.4GHz.In addition,the layout of the eight-way CMOS passive power divider is designed,and the post-simulation results of the S-parameters are given.The post simulation results of S-parameters show that the circuit still has good performance.Secondly,in order to compensate for the losses introduced by passive devices such as inductors and capacitors in the circuit,the ultra-wideband CMOS active power divider is designed.By adding active bidirectional amplifiers to the circuit,the lumped inductors and the parasitic capacitance in the bidirectional amplifiers constitute the artificial transmission lines.The structures of the two-way and the eight-way power dividers circuits are proposed,and the pre-simulation of S-parameters is carried out.Among them,the operating frequency ranges of both the two-way and the eight-way power dividers are 10.2GHz-32 GHz.The maximum gain of the two-way power divider circuit is 8.0d B,and the highest isolation can reach-70 d B.The maximum gain of the eight-way power divider circuit is 20.0d B,and the highest isolation can reach more than-100 d B.Finally,the layouts of the two-way and the eight-way CMOS active power dividers circuits are designed,and the pre-simulation results and the post-simulation results of the S-parameters are given.After extracting the parasitic parameters,the post-simulation results of the S-parameters show that the operating bandwidth of the circuits are almost unchanged,and the circuits achieve good matching and still meet the design requirements of ultra-wideband,low loss,and high isolation.