In order to realize accurate bilinear transformation from s- to z-domain,a novelswitched-capacitor configuration is proposed in the light of principles of dual-rate sampling and chargeconservation,which has also been ...In order to realize accurate bilinear transformation from s- to z-domain,a novelswitched-capacitor configuration is proposed in the light of principles of dual-rate sampling and chargeconservation,which has also been used for building a 5th-order elliptic lowpass filter.The filter issimulated and measured in typical 0.34 μm/3.3 V Si CMOS process models,special full differentialoperational amplifiers and CMOS transfer gate switches,which achieves 80 MHz sampling rate,17.8MHz cutoff frequency,0.052 dB maximum passband ripple,42.1 dB minimum stopband attenuation and74 mW quiescent power dissipation.At the same time,the dual-rate sampling topology breaks thetraditional restrictions of filter introduced by unit-gain bandwidth and slew rate of operational amplifiersand also improves effectively their performances in high-frequency applications.It has been applied forthe design of an anti-alias filter in analog front-end of video decoder IC with 15 MHz signal frequencyyet.展开更多
The design approach and performance of a 22.5°/45°digital phase shifter based on a switched filter network for X-band phased arrays are described.Both the MMIC phase shifters are fabricated employing a 0.25 ...The design approach and performance of a 22.5°/45°digital phase shifter based on a switched filter network for X-band phased arrays are described.Both the MMIC phase shifters are fabricated employing a 0.25 m gate GaAs pHEMT process and share in the same chip size of 0.82 1.06 mm^2.The measurement results of the proposed phase shifters over the whole operating frequency range show that the phase shift error is less than 22.5°˙2.5°,45°˙3.5°,which shows an excellent agreement with the simulated performance,the insertion loss is within the range of 0.9–1.2 dB for the 22.5° phase shifter and 0.9–1.4 dB for the 45°phase shifter,and the input/output return loss is better than –12.5 and –11 dB respectively.They also achieve the similar P（1dB）continuous wave power handing capability of 24.8 dBm at 10 GHz.The phase shifters show a good phase shift error,insertion loss and return loss in the X-band（40%）,which can be employed into the wide bandwidth multi-bit digital phase shifter.展开更多
基金Supported by the National Nature Science Foundation(No. 60072004)and the University Postgraduate Station Foundation of China(No.2000061402)
文摘In order to realize accurate bilinear transformation from s- to z-domain,a novelswitched-capacitor configuration is proposed in the light of principles of dual-rate sampling and chargeconservation,which has also been used for building a 5th-order elliptic lowpass filter.The filter issimulated and measured in typical 0.34 μm/3.3 V Si CMOS process models,special full differentialoperational amplifiers and CMOS transfer gate switches,which achieves 80 MHz sampling rate,17.8MHz cutoff frequency,0.052 dB maximum passband ripple,42.1 dB minimum stopband attenuation and74 mW quiescent power dissipation.At the same time,the dual-rate sampling topology breaks thetraditional restrictions of filter introduced by unit-gain bandwidth and slew rate of operational amplifiersand also improves effectively their performances in high-frequency applications.It has been applied forthe design of an anti-alias filter in analog front-end of video decoder IC with 15 MHz signal frequencyyet.
文摘The design approach and performance of a 22.5°/45°digital phase shifter based on a switched filter network for X-band phased arrays are described.Both the MMIC phase shifters are fabricated employing a 0.25 m gate GaAs pHEMT process and share in the same chip size of 0.82 1.06 mm^2.The measurement results of the proposed phase shifters over the whole operating frequency range show that the phase shift error is less than 22.5°˙2.5°,45°˙3.5°,which shows an excellent agreement with the simulated performance,the insertion loss is within the range of 0.9–1.2 dB for the 22.5° phase shifter and 0.9–1.4 dB for the 45°phase shifter,and the input/output return loss is better than –12.5 and –11 dB respectively.They also achieve the similar P（1dB）continuous wave power handing capability of 24.8 dBm at 10 GHz.The phase shifters show a good phase shift error,insertion loss and return loss in the X-band（40%）,which can be employed into the wide bandwidth multi-bit digital phase shifter.
