Broadband and Low-loss Symmetric Offset Stack CMOS Balun for Passive Mixer Designs

• Main Authors: Jui-yi Lin, 林瑞益
• Other Authors: Hwann-kaeo Chiou
• Format: Others
• Language: en_US
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/56051525392028965662

博士 === 國立中央大學 === 電機工程研究所 === 99 === The purpose of this dissertation is to design, analyze and implement broadband and low-loss Marchand balun in 0.18 um CMOS process to verify the feasibility, and then the balun is used in five passive mixers in standard CMOS technology. The topology of this Marchand balun is utilized a symmetrical offset stack coupled line structure. To achieve a minimum insertion loss and a maximum bandwidth, the design formulas are derived by proper selected the width of coupled lines and the offset width between two coupled lines. The design procedure for the balun is verified by practical implementation. The measured results are agreed with the theoretical analysis. Compare with the literature survey of the recently reported Marchand baluns; the proposed Marchand balun shows the better bandwidth and insertion loss performance. Both single and dual baluns achieve the measured bandwidths of over 110% and 90%, and insertion losses of less than 4.4 dB and 7.4 dB at 38 GHz. These two baluns occupied chip sizes of 0.07 mm2. Three balanced resistive mixers and two balanced diode mixers are further proposed and implemented in tsmcTM 0.13-um and 0.18-um CMOS processes. These mixers utilized a stack balun feature a wide bandwidth performance with very compact size. The balanced resistive mixers exhibit wide bandwidths over 14-45 GHz (105%), 18-54 GHz (100%) and 28-50 GHz (56%). The 14-45 GHz SBRM achieves a conversion loss of better than 12 dB at 7 dBm of local oscillator (LO) power. The LO to RF and LO to IF isolations are better than 30 dB. The chip area is 0.53 mm2. The star mixer achieves a conversion loss of better than 12 dB from 18 to 54 GHz, and LO to RF, LO to IF and RF to IF isolations better than 35 dB at LO frequencies spanning 10 to 60 GHz. The chip area is 0.6 mm2. The SHPRM has a conversion loss of better than 11 dB from 28 to 50 GHz. The isolations are better than 31 dB and occupy a chip area of 0.61 mm2. Two balanced diode mixers exhibit bandwidths over 20-60 GHz (100%) and 14-52 GHz (115%). The single balanced diode mixer achieves conversion loss lower than 15 dB with compact chip size of 0.24 mm2. The star diode mixer has conversion loss of lower than 15 dB 14 to 52 GHz. The chip size is only 0.4 mm2.