An active-RC low-pass filter of 5MHz cutoff frequency with a tuning architecture is proposed. It is implemented in 0. 18μm standard CMOS technology. The accuracy of the tuning system is improved to be within ( - 1.2...An active-RC low-pass filter of 5MHz cutoff frequency with a tuning architecture is proposed. It is implemented in 0. 18μm standard CMOS technology. The accuracy of the tuning system is improved to be within ( - 1.24%, + 2.16%) in measurement. The chip area of the tuning system is only a quarter of that of the main-filter. After tuning is completed, the tuning system will be turned off automatically to save power and to avoid interference. The in-band 3rd order harmonic input intercept point (IIP3) is larger than 16. ldBm, with 50Ω as the source impedance. The input referred noise is about 36μVrms The measured group delay variation of the filter between 3 and 5MHz is only 24ns,and the filter power consump- tion is 3.6roW. This filter with the tuning system is realized easily and can be used in many wireless low-IF receiver applications, such as global position systems (GPS), global system for mobile communications (GSM) and code division multiple access (CDMA) chips.展开更多
A tunable microwave photonic bandpass filter with high mainlobe-to-sidelobe ratio (MSR) based on a phase modulator and a dispersive device is proposed. The multi-tap characteristics of the filter are realized by slici...A tunable microwave photonic bandpass filter with high mainlobe-to-sidelobe ratio (MSR) based on a phase modulator and a dispersive device is proposed. The multi-tap characteristics of the filter are realized by slicing a broadband source using a Mach-Zehnder interferometer (MZI) which results in a high MSR of 25 dB. The tunability of the filter is realized by an optical variable delay line (OVDL) in one arm of the MZI, which changes the wavelength spacing of the sliced broadband source and results in a tunable free spectrum range (FSR) of the filter. The central frequency of the bandpass filter is tunable from 10.7 GHz to 27 GHz by changing the wavelength spacing from 0.145 nm to 0.054 nm.展开更多
文摘An active-RC low-pass filter of 5MHz cutoff frequency with a tuning architecture is proposed. It is implemented in 0. 18μm standard CMOS technology. The accuracy of the tuning system is improved to be within ( - 1.24%, + 2.16%) in measurement. The chip area of the tuning system is only a quarter of that of the main-filter. After tuning is completed, the tuning system will be turned off automatically to save power and to avoid interference. The in-band 3rd order harmonic input intercept point (IIP3) is larger than 16. ldBm, with 50Ω as the source impedance. The input referred noise is about 36μVrms The measured group delay variation of the filter between 3 and 5MHz is only 24ns,and the filter power consump- tion is 3.6roW. This filter with the tuning system is realized easily and can be used in many wireless low-IF receiver applications, such as global position systems (GPS), global system for mobile communications (GSM) and code division multiple access (CDMA) chips.
基金supported by the National Natural Science Foundation of China (No.60808004)the New Century Excellent Talents in University (No.NCET-07-0611)the Tianjin Natural Science Foundation (No.08JCYBJC14500)
文摘A tunable microwave photonic bandpass filter with high mainlobe-to-sidelobe ratio (MSR) based on a phase modulator and a dispersive device is proposed. The multi-tap characteristics of the filter are realized by slicing a broadband source using a Mach-Zehnder interferometer (MZI) which results in a high MSR of 25 dB. The tunability of the filter is realized by an optical variable delay line (OVDL) in one arm of the MZI, which changes the wavelength spacing of the sliced broadband source and results in a tunable free spectrum range (FSR) of the filter. The central frequency of the bandpass filter is tunable from 10.7 GHz to 27 GHz by changing the wavelength spacing from 0.145 nm to 0.054 nm.