Browsing by Author "Chou, Mei-Fen"

Now showing 1 - 5 of 5

A CMOS distributed amplifier with current reuse optimization
(2006)
Chou, Mei-Fen
;
Tsou, Wen-An
;
Dunn, Robert H.
;
Huang, Hsiang-Lin
;
Wen, Kuei-Ann
A CMOS distributed amplifier with current reuse optimization is presented. Using current reuse technique, the distributed amplifier achieves low power consumption while retaining the same gain-bandwidth product in comparison with standard common-source topology. The DA demonstrates low current consumption of only,12.9 mA with 4 dB gain from 3 to 8 GHz using a 0.18-mu m CMOS technology. An analog behavior model is also developed for system-level simulation to shorten the design time and increase design quality for future integrated wide.-band transceivers.
A Multi-band Frequency Synthesizer for GSM/DCS/WIMAX/WLAN Applications with Ripple-free Circuit
(2010)
Chen, Po-Heng
;
Chen, Che-Sheng
;
Chou, Mei-Fen
;
Wen, Kuei-Ann
;
電子工程學系及電子研究所
This paper presents a fully integrated multi- band frequency synthesizer implemented in CMOS 0.18 mu m process with ripple-free circuit in a single loop. The synthesizer is designed for GSM/ DCS/WIMAX/WLAN (802.11a/b/g) systems applying to IQ phase based transceivers. The proposed synthesizer with ripple-free circuit can reduce the amplitude of control voltage ripple. The synthesizer performs the suppression of 31.4dB in the spectrum of reference-spur and the peak-to-peak jitter with 74% improvement compared to the conventional single loop synthesizer design.
A Polar Modulated Tri-band Power Amplifier Using Flexible Substrate Based MEMS Switches
(2010-01-01)
Lai, Chung-Min
;
Chao, Tzu-Yuan
;
Tsou, Wen-An
;
Chou, Mei-Fen
;
Cheng, Yu-Ting
In this work, the phase compensation techniques by means of self-biasing control and an additional tuning capacitor for polar modulated tri-band Class-E power amplifier is proposed. The tri-band power amplifier operating at 2.3 similar to 2.7/3.3 similar to 3.8/5.1 similar to 5.8 GHz for WLAN and WiMAX applications adjusts low loss Micro-Electro-Mechanical-Systems (MEMS) switches to select the matching networks. The improvement of phase distortion and system relative constellation error (RCE) is 36.4 degrees and 8.9dB, respectively. Simulation results shows that the maximum power-added efficiency (PAE) of 34.9%, drain efficiency of 37.3%, and output power of 18.8dBm from 2.8V supply can be achieved in 0.18 mu m CMOS Technology.
A unified behavior model of low noise amplifier for system-level simulation
(2006)
Hung, Chih-De
;
Wuen, Wen-Shen
;
Chou, Mei-Fen
;
Wen, Kuei-Ann
;
電子工程學系及電子研究所
This paper presents a unified RF behavior model that simultaneously predicts the effects of noise, nonlinearity, impedance matching and frequency response and that enables efficient and accurate system simulation. The proposed modeling approach allows characterizing the RF effects incrementally to reduce iteration. A Verilog-A behavior model for an ultra-wideband CMOS low noise amplifier is developed for fast and accurate system simulation. The system simulation results show that the behavior model agrees well with the transistor-level circuit with RMS error less than 0.79%. Ultimately, 87% reduction of simulation time is achieved.
TRI-BAND CMOS CLASS-E POWER AMPLIFIER DESIGN WITH PHASE COMPENSATIONS FOR POLAR SYSTEMS
(2010)
Lai, Chung-Min
;
Tsou, Wen-An
;
Chou, Mei-Fen
;
Wen, Kuei-Ann
;
電子工程學系及電子研究所
A 0.18 mu m CMOS fully integrated cascode Class-E power amplifier operating in 2.5GHz/3.5GHz/5.2GHz frequency bands for polar transmitters has been proposed. The tri-band amplification is achieved by adaptation of the common-gate transistor size and the matching networks. The phase distortion from supply modulation of the Class-E is compensated by controlling the common-gate transistor gate voltage and a compensative capacitor. Simulation results show that the maximum power-added efficiency (PAE) of 30.4%, drain efficiency of 34% and output power of 18.8dBm from 2.8V supply can be achieved. The phase distortion can be compensated from 34.4 degrees to 3.1 degrees under supply voltage of 0.5V to 2.8V. A system co-simulation has been established for relative constellation error (RCE) evaluation and it reveals that the RCE can be improved from -23.3dB to -31.4dB in 3.5GHz frequency band.