Title :
A balanced reflection type HMIC vector modulator over 34–36GHz based on cold state pHEMTs
Author :
Dongquan Sun ; Yanyan Fan ; Jinping Xu ; Shu Jiang
Author_Institution :
State Key Lab. of Millimeter Waves, Southeast Univ., Nanjing, China
fDate :
March 30 2015-April 1 2015
Abstract :
A vector modulatorat Ka band consisting of two balanced I/Q bi-phase attenuatorsis presented in this paper. The bi-phase attenuators are of reflection type, in which cold state pHEMTs are employed as tunable impedance loads. Due to the balanced structure, parasitic effects of the pHEMTs are effectively cancelled. A prototype of the vector modulator is fabricated by HMIC technique. The measured dynamic range of amplitude is about 28dB with 360 degree tunable phase. The maximum transmission coefficient is about -8dB while the return loss is better than 15dB at the whole operation band of 34-36GHz.
Keywords :
modulators; transistors; HMIC vector modulator; I/Q bi-phase attenuatorsis; balanced reflection; balanced structure; cold state pHEMT; parasitic effects; pseudomorphic high electron mobility transistors; tunable impedance loads; vector modulator; Binary phase shift keying; Frequency modulation; Microwave communication; Optical modulation; Optical reflection; Phase measurement; Q measurement; I/Q; Ka band; balanced structure; pHEMT; reflection type; vector modulator;
Conference_Titel :
Wireless Symposium (IWS), 2015 IEEE International
Conference_Location :
Shenzhen
DOI :
10.1109/IEEE-IWS.2015.7164511
