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HongTeuk Kim

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Dr. Abdullah Alburaikan

The University of New South Wales

Evangelia Karagianni

HELLENIC NAVAL ACADEMY

Dr. Yazen Adnan Khaleel

Koya University

Syed Idris Syed Hassan

Wahab Mohyuddin

Manoj Singh Parihar

PDPM-Indian Institute of Information Technology,Design and Manufacturing,jabalpur

National Changhua University of Education

Jean-daniel Arnould

Institut polytechnique de Grenoble - Grenoble INP

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Papers by HongTeuk Kim

Compact low-loss monolithic CPW filters using air-gap overlay structures

IEEE Microwave and Wireless Components Letters, 2001

In this letter, two types of compact low-loss monolithic coplanar waveguide (CPW) filters using a... more In this letter, two types of compact low-loss monolithic coplanar waveguide (CPW) filters using air-gap overlay structures are presented. Vertical stacking in overlay structures offers size reduction. Furthermore, air-gap overlay structures do not require additional dielectric process and are free from dielectric losses. An X-band bandpass filter using air-gap overlaid artificial transmission lines showed 67% size reduction. A stepped-impedance low-pass filter using highly separated metal-air-metal (MAM) capacitors as low-impedance lines achieved not only siz, but also loss reduction. Small size, low loss, and simple process steps make the air-gap overlay structures very promising for monolithic CPW passive devices such as filters.

Low-loss micromachined inverted overlay CPW lines with wide impedance ranges and inherent airbridge connection capability

IEEE Microwave and Wireless Components Letters, 2001

A new type of overlay coplanar waveguide (CPW) structure, "inverted overlay CPW (IOCPW)" is devel... more A new type of overlay coplanar waveguide (CPW) structure, "inverted overlay CPW (IOCPW)" is developed using micromachining techniques to provide easy means of airbridge connection between the ground planes, as well as to achieve low losses over wide impedance ranges. Measured IOCPW showed less than 1 dB/cm loss at 50 GHz over a wide impedance range from 25 to 80. It also offered low effective dielectric constant, and insensitivity to the substrate losses. Wide impedance ranges and simple process steps make IOCPW a promising uniplanar transmission line medium for mm-wave monolithic applications.

A wideband MMIC-compatible balun using offset broadside air-gap coupling

IEEE Microwave and Wireless Components Letters, 2004

A compact ultra-broadband MMIC-compatible uniplanar balun has been developed using offset air-gap... more A compact ultra-broadband MMIC-compatible uniplanar balun has been developed using offset air-gap coupler. The offset air-gap coupler presents tight coupling and low conductor loss, and thus allows the balun to show low loss at mm-wave frequencies. The measured insertion loss was less than 2 dB from 26 to 55 GHz, and amplitude and phase imbalance was less than 1 dB and 5 , respectively over a wide frequency range from 27 to 69 GHz.

A compact V-band 2-bit reflection-type MEMS phase shifter

IEEE Microwave and Wireless Components Letters, 2002

Air-gap overlay CPW couplers and low-loss series metal-to-metal contact microelectromechanical sy... more Air-gap overlay CPW couplers and low-loss series metal-to-metal contact microelectromechanical system (MEMS) switches have been employed to reduce the loss of reflection-type MEMS phase shifters at V-band. Phase shift is obtained by changing the lengths of the open-ended stubs using series MEMS switches. A 2-bit (135) reflection-type MEMS phase shifter showed an average insertion loss of 4 dB with return loss better than 11.7 dB from 50 to 70 GHz. The chip is very compact with a chip size as small as 1.5 mm 2.1 mm.

A wideband CMOS variable-gain low noise amplifier with novel attenuator

2013 IEEE 10th International Conference on ASIC, 2013

This paper presents a wideband variable-gain low noise amplifier (VGLNA) which is used in mobile ... more This paper presents a wideband variable-gain low noise amplifier (VGLNA) which is used in mobile TV tuner covering VHF band (50 to 250 MHz) and UHF band (470 to 860MHz). The proposed VGLNA includes three gain paths for different input signal strengths: high gain path, attenuation path, medium gain path. The high gain path is realized by an active AC feedback LNA, whose DC current is set by a constant-G m biasing; the novel attenuator used in attenuation path has constant input impedance which guarantees a good S11 with the variety of gain; the medium gain path is the combination of one active AC feedback LNA and one attenuator. The chip is implemented in 0.18 m CMOS process and achieves a gain range over 42 dB (2dB/step), a minimum noise figure of 2 dB at maximum gain, an IIP3 of 27.9 dBm at minimum gain. The die consumes 8 mA from 1.8 V supply voltage at maximum gain.

Low-loss and compact V-band MEMS-based analog tunable bandpass filters

IEEE Microwave and Wireless Components Letters, 2002

This paper presents compact V-band MEMS-based analog tunable bandpass filters with improved tunin... more This paper presents compact V-band MEMS-based analog tunable bandpass filters with improved tuning ranges and low losses. For compact size and wide tuning range, the two-pole filters are designed using the lumped-elements topology with metal-air-metal (MAM) bridge-type capacitors as tuning elements. Capacitive inter-resonator coupling has been employed to minimize the radiation loss, which is the main loss contributor at high frequencies. Two filters have been demonstrated at 50 and 65 GHz. The 65-GHz analog tunable filter showed a frequency tuning bandwidth of 10% (6.5 GHz) with low and flat insertion losses of 3.3 0.2 dB over the entire tuning range.

Design methodology of baseband analog chain to maximize a spurious free dynamic range for ATSC terrestrial and cable digital TV tuner

IEEE Transactions on Consumer Electronics, 2008

This paper presents a fully integrated tunable CMOS baseband analog (BBA) chain optimized for adv... more This paper presents a fully integrated tunable CMOS baseband analog (BBA) chain optimized for advanced television systems committee (ATSC) terrestrial and cable digital TV tuner integrated circuits (ICs). To maximize the spurious free dynamic range (SFDR) of the BBA chain for both standards, the design guideline is introduced with respect to the optimized allocation of the gain of each block. The bandwidth is selectable from 3 MHz, 3.5 MHz, or 4 MHz. Fabricated in a 0.18-μm CMOS process, it provides a minimum input referred noise density of 15.5 nV/ Hz with 62 dB gain and out-of-channel output referred third-order intercept point (OIP3) of 33 dBm, while it drains an average current of 89 mA from 3.3 V. The total chip area is 1 mm × 1.2 mm . 1

A Highly Linear Wideband CMOS Low-Noise Amplifier Based on Current Amplification for Digital TV Tuner Applications

IEEE Microwave and Wireless Components Letters, 2008

A differential wideband low-noise amplifier (LNA) based on the current amplification scheme is pr... more A differential wideband low-noise amplifier (LNA) based on the current amplification scheme is presented for digital TV tuners. In order to highly improve the linearity and exploit the noise cancellation, a common-gate stage with positive current feedback is integrated in parallel with a common-source stage using the current mirror amplifier. The proposed 0.18-m CMOS LNA exhibits a power gain of 20.5 dB, an IIP3 of 2.7 dBm, an IIP2 of 43 dBm, and an average noise figure of 3.3 dB with 32.4 mW power consumption at a 1.8-V power supply and 0.12 mm 2 area.

A Wideband CMOS Low Noise Amplifier Employing Noise and IM2 Distortion Cancellation for a Digital TV Tuner

IEEE Journal of Solid-State Circuits, 2009

A wideband CMOS low noise amplifier (LNA) with single-ended input and output employing noise and ... more A wideband CMOS low noise amplifier (LNA) with single-ended input and output employing noise and IM2 distortion cancellation for a digital terrestrial and cable TV tuner is presented. By adopting a noise canceling structure combining a common source amplifier and a common gate amplifier by current amplification, the LNA obtains a low noise figure and high IIP3. IIP2 as well as IIP3 of the LNA is important in broadband systems, especially digital terrestrial and cable TV applications. Accordingly, in order to overcome the poor IIP2 performance of conventional LNAs with single-ended input and output and avoid the use of external and bulky passive transformers along with high sensitivity, an IM2 distortion cancellation technique exploiting the complementary RF performance of NMOS and PMOS while retaining thermal noise canceling is adopted in the LNA. The proposed LNA is implemented in a 0.18 m CMOS process and achieves a power gain of 14 dB, an average noise figure of 3 dB, an IIP3 of 3 dBm, an IIP2 of 44 dBm at maximum gain, and S11 of under 9 dB in a frequency range from 50 MHz to 880 MHz. The power consumption is 34.8 mW at 2.2 V and the chip area is 0.16 mm 2 .

Low-Loss Analog and Digital Reflection-Type MEMS Phase Shifters With 1 : 3 Bandwidth

IEEE Transactions on Microwave Theory and Techniques, 2004

Broad-band analog and digital reflection-type phase shifters (RTPSs), showing constant phase shif... more Broad-band analog and digital reflection-type phase shifters (RTPSs), showing constant phase shift over 1 : 3 bandwidth, have been developed using microelectromechanical systems (MEMS) technology. Two-unit RTPSs centered at two different frequencies have been cascaded to achieve flat phase responses over a wide frequency band. Each phase shifter uses air-gap overlay coplanar-waveguide couplers for low-loss 3-dB coupling and bridge-type MEMS capacitors for reflective terminations. The fabricated analog phase shifter shows the average insertion loss of 3.5 dB, and maximum phase error of 4.9 from 15 to 45 GHz. The 2-bit digital RTPS shows reduced maximum phase error of 2.8 together with a comparable insertion loss of 3.1 dB from 5 to 15 GHz. The details of the circuit design, analysis, and fabrication procedures are presented together with the measurement results. Compared with the similar constant phase shifters using semiconductor diodes and transistors, the micromachined RTPS of this study shows superior performance in terms of phase errors, insertion losses, and bandwidth. Index Terms-Broad-band, microelectromechanical systems (MEMS) variable capacitor, micromachining technology, phase shifter. I. INTRODUCTION R ADIO-FREQUENCY (RF) microelectromechanical systems (MEMS) technologies have been successfully applied to the development of low-loss RF switching devices and variable capacitors [1], [2]. RF MEMS capacitive switches and variable capacitors have demonstrated significant performance advantages over the conventional electrical p-in diodes and varactors in terms of lower loss, lower parasitics, and higher linearity. Due to these advantages, they have been enabling components for a low-loss phase shifter, which is a critical circuit for modern radar and communications systems. A number of micromachined phase shifters using MEMS technology have been developed for active phased-array antennas [3], [4]. These phase shifters are based on either distributed loaded lines or switched lines and, thus, exhibit linear relationship between the relative phase shift and frequency.

Antenna for enhancing bandwidth and electronic device having the same

Antenna and Electronic Equipment Having the Same

6-18 GHz MMIC Drive and Power Amplifiers

Journal of Semiconductor Technology and Science

ABSTRACT

Novel micromachined CPW transmission lines for application in millimeter-wave circuits

Digest of Papers Microprocesses and Nanotechnology 2000. 2000 International Microprocesses and Nanotechnology Conference (IEEE Cat. No.00EX387), 2000

V-band low-loss and low-voltage distributed MEMS digital phase shifter using metal-air-metal capacitors

2002 IEEE MTT-S International Microwave Symposium Digest (Cat. No.02CH37278), 2002

A low-loss digital distributed phase shifter has been developed using micromachined capacitive sh... more A low-loss digital distributed phase shifter has been developed using micromachined capacitive shunt switches for V-band communication system. Instead of conventional MIM (metal-insulator-metal) capacitors, high-Q MAM (metal-air-metal) capacitors were used in series with the MEMS shunt capacitive switches to minimize the dielectric loss. The operation voltage for the phase shifter was also reduced by applying the bias directly to the MEMS shunt switches through choke spiral inductors. The fabricated 2-bit (270°) distributed phase shifter showed low average insertion loss of 2.2 dB at 60 GHz. The return loss is better than 10 dB over a wide frequency range from 40 to 70 GHz. The circuit operates at 15-20 V bias voltages. This phase shifter is very promising for the integrated circuits at V-band requiring low loss and good return loss over a broad band.

A 15-to-45 GHz low-loss analog reflection-type MEMS phase shifter

IEEE MTT-S International Microwave Symposium Digest, 2003, 2003

A low-loss broadband reflection-type phase shifter (RTPS), showing constant phase shift from 15 t... more A low-loss broadband reflection-type phase shifter (RTPS), showing constant phase shift from 15 to 45 GHz, was developed using MEMS technology. The analog phase shifter consists of two cascaded reflection-type phase shifters for 1:3 bandwidth. Air-gap overlay CPW couplers were employed for low-loss 3 dB coupling, and bridge-type MEMS variable capacitors were used for low-loss reflective terminations. The fabricated phase

A V-band CPS distributed analog MEMS phase shifter

IEEE MTT-S International Microwave Symposium Digest, 2003, 2003

ABSTRACT

A Micromachined Millimeter Wave Phase Shifter Using Semi-Lumped Elements

Transducers ’01 Eurosensors XV, 2001

This paper demonstrates a surface micromachined millimeter wave phase shifter with small size and... more This paper demonstrates a surface micromachined millimeter wave phase shifter with small size and large phase shift per line loss using semi-lumped elements transmission structure. The multi-pole phase shifter can be easily fabricated by cascading the unit cell. The unit cell of the phase shifter is composed of the high impedance center signal line and bridge type variable capacitors. The variable capacitors are suspended 2 over the plate connected to the both sides of the signal line to reduce the unit cell length, resulting in high phase shift per line length. The measured pull-in voltage of the variable capacitor is 50 V. The fabricated phase shifter shows high phase shift per loss (76.2 ¶/dB) as well as the high phase shift per line length (25.3 ¶/mm) at 50 GHz with the applied DC bias of 45 V.

Millimeter-wave micromachined tunable filters

1999 IEEE MTT-S International Microwave Symposium Digest (Cat. No.99CH36282), 1999

Novel types of mm-wave tunable filters using micromachined variable capacitors are presented. In ... more Novel types of mm-wave tunable filters using micromachined variable capacitors are presented. In order to demonstrate this concept, two bandpass filters, one with 2-pole lumped elements and the other with 2- pole resonators are designed at Ka-band and fabricated using MEMS technology. With applied bias, the center frequency shift as much as 1.1 GHz (4.2 %) at 26.6 GHz, and 0.8 GHz (2.5 YO) at 32 GHz, was measured for lumped elements and resonators filter, respectively. These results show the potentials of micromachined tunable filters for low cost, highly integrated transmitter and receiver for mm-wave multi band communication systems.

Wide-band CMOS loop-through amplifier for Cable TV tuner

2008 IEEE Radio Frequency Integrated Circuits Symposium, 2008

A fully integrated loop-through amplifier (LTA) for cable TV tuner is presented in a 0.18 mum CMO... more A fully integrated loop-through amplifier (LTA) for cable TV tuner is presented in a 0.18 mum CMOS process. It covers the whole frequency band from 48 MHz to 860 MHz and allows a second TV and multiple tuners. This circuit employs a parallel connection of common-gate and common-source (CG-CS) amplifiers for broadband matching. The performances are enhanced by current amplification

Compact low-loss monolithic CPW filters using air-gap overlay structures

IEEE Microwave and Wireless Components Letters, 2001

In this letter, two types of compact low-loss monolithic coplanar waveguide (CPW) filters using a... more In this letter, two types of compact low-loss monolithic coplanar waveguide (CPW) filters using air-gap overlay structures are presented. Vertical stacking in overlay structures offers size reduction. Furthermore, air-gap overlay structures do not require additional dielectric process and are free from dielectric losses. An X-band bandpass filter using air-gap overlaid artificial transmission lines showed 67% size reduction. A stepped-impedance low-pass filter using highly separated metal-air-metal (MAM) capacitors as low-impedance lines achieved not only siz, but also loss reduction. Small size, low loss, and simple process steps make the air-gap overlay structures very promising for monolithic CPW passive devices such as filters.

Low-loss micromachined inverted overlay CPW lines with wide impedance ranges and inherent airbridge connection capability

IEEE Microwave and Wireless Components Letters, 2001

A new type of overlay coplanar waveguide (CPW) structure, "inverted overlay CPW (IOCPW)" is devel... more A new type of overlay coplanar waveguide (CPW) structure, "inverted overlay CPW (IOCPW)" is developed using micromachining techniques to provide easy means of airbridge connection between the ground planes, as well as to achieve low losses over wide impedance ranges. Measured IOCPW showed less than 1 dB/cm loss at 50 GHz over a wide impedance range from 25 to 80. It also offered low effective dielectric constant, and insensitivity to the substrate losses. Wide impedance ranges and simple process steps make IOCPW a promising uniplanar transmission line medium for mm-wave monolithic applications.

A wideband MMIC-compatible balun using offset broadside air-gap coupling

IEEE Microwave and Wireless Components Letters, 2004

A compact ultra-broadband MMIC-compatible uniplanar balun has been developed using offset air-gap... more A compact ultra-broadband MMIC-compatible uniplanar balun has been developed using offset air-gap coupler. The offset air-gap coupler presents tight coupling and low conductor loss, and thus allows the balun to show low loss at mm-wave frequencies. The measured insertion loss was less than 2 dB from 26 to 55 GHz, and amplitude and phase imbalance was less than 1 dB and 5 , respectively over a wide frequency range from 27 to 69 GHz.

A compact V-band 2-bit reflection-type MEMS phase shifter

IEEE Microwave and Wireless Components Letters, 2002

Air-gap overlay CPW couplers and low-loss series metal-to-metal contact microelectromechanical sy... more Air-gap overlay CPW couplers and low-loss series metal-to-metal contact microelectromechanical system (MEMS) switches have been employed to reduce the loss of reflection-type MEMS phase shifters at V-band. Phase shift is obtained by changing the lengths of the open-ended stubs using series MEMS switches. A 2-bit (135) reflection-type MEMS phase shifter showed an average insertion loss of 4 dB with return loss better than 11.7 dB from 50 to 70 GHz. The chip is very compact with a chip size as small as 1.5 mm 2.1 mm.

A wideband CMOS variable-gain low noise amplifier with novel attenuator

2013 IEEE 10th International Conference on ASIC, 2013

This paper presents a wideband variable-gain low noise amplifier (VGLNA) which is used in mobile ... more This paper presents a wideband variable-gain low noise amplifier (VGLNA) which is used in mobile TV tuner covering VHF band (50 to 250 MHz) and UHF band (470 to 860MHz). The proposed VGLNA includes three gain paths for different input signal strengths: high gain path, attenuation path, medium gain path. The high gain path is realized by an active AC feedback LNA, whose DC current is set by a constant-G m biasing; the novel attenuator used in attenuation path has constant input impedance which guarantees a good S11 with the variety of gain; the medium gain path is the combination of one active AC feedback LNA and one attenuator. The chip is implemented in 0.18 m CMOS process and achieves a gain range over 42 dB (2dB/step), a minimum noise figure of 2 dB at maximum gain, an IIP3 of 27.9 dBm at minimum gain. The die consumes 8 mA from 1.8 V supply voltage at maximum gain.

Low-loss and compact V-band MEMS-based analog tunable bandpass filters

IEEE Microwave and Wireless Components Letters, 2002

This paper presents compact V-band MEMS-based analog tunable bandpass filters with improved tunin... more This paper presents compact V-band MEMS-based analog tunable bandpass filters with improved tuning ranges and low losses. For compact size and wide tuning range, the two-pole filters are designed using the lumped-elements topology with metal-air-metal (MAM) bridge-type capacitors as tuning elements. Capacitive inter-resonator coupling has been employed to minimize the radiation loss, which is the main loss contributor at high frequencies. Two filters have been demonstrated at 50 and 65 GHz. The 65-GHz analog tunable filter showed a frequency tuning bandwidth of 10% (6.5 GHz) with low and flat insertion losses of 3.3 0.2 dB over the entire tuning range.

Design methodology of baseband analog chain to maximize a spurious free dynamic range for ATSC terrestrial and cable digital TV tuner

IEEE Transactions on Consumer Electronics, 2008

This paper presents a fully integrated tunable CMOS baseband analog (BBA) chain optimized for adv... more This paper presents a fully integrated tunable CMOS baseband analog (BBA) chain optimized for advanced television systems committee (ATSC) terrestrial and cable digital TV tuner integrated circuits (ICs). To maximize the spurious free dynamic range (SFDR) of the BBA chain for both standards, the design guideline is introduced with respect to the optimized allocation of the gain of each block. The bandwidth is selectable from 3 MHz, 3.5 MHz, or 4 MHz. Fabricated in a 0.18-μm CMOS process, it provides a minimum input referred noise density of 15.5 nV/ Hz with 62 dB gain and out-of-channel output referred third-order intercept point (OIP3) of 33 dBm, while it drains an average current of 89 mA from 3.3 V. The total chip area is 1 mm × 1.2 mm . 1

A Highly Linear Wideband CMOS Low-Noise Amplifier Based on Current Amplification for Digital TV Tuner Applications

IEEE Microwave and Wireless Components Letters, 2008

A differential wideband low-noise amplifier (LNA) based on the current amplification scheme is pr... more A differential wideband low-noise amplifier (LNA) based on the current amplification scheme is presented for digital TV tuners. In order to highly improve the linearity and exploit the noise cancellation, a common-gate stage with positive current feedback is integrated in parallel with a common-source stage using the current mirror amplifier. The proposed 0.18-m CMOS LNA exhibits a power gain of 20.5 dB, an IIP3 of 2.7 dBm, an IIP2 of 43 dBm, and an average noise figure of 3.3 dB with 32.4 mW power consumption at a 1.8-V power supply and 0.12 mm 2 area.

A Wideband CMOS Low Noise Amplifier Employing Noise and IM2 Distortion Cancellation for a Digital TV Tuner

IEEE Journal of Solid-State Circuits, 2009

A wideband CMOS low noise amplifier (LNA) with single-ended input and output employing noise and ... more A wideband CMOS low noise amplifier (LNA) with single-ended input and output employing noise and IM2 distortion cancellation for a digital terrestrial and cable TV tuner is presented. By adopting a noise canceling structure combining a common source amplifier and a common gate amplifier by current amplification, the LNA obtains a low noise figure and high IIP3. IIP2 as well as IIP3 of the LNA is important in broadband systems, especially digital terrestrial and cable TV applications. Accordingly, in order to overcome the poor IIP2 performance of conventional LNAs with single-ended input and output and avoid the use of external and bulky passive transformers along with high sensitivity, an IM2 distortion cancellation technique exploiting the complementary RF performance of NMOS and PMOS while retaining thermal noise canceling is adopted in the LNA. The proposed LNA is implemented in a 0.18 m CMOS process and achieves a power gain of 14 dB, an average noise figure of 3 dB, an IIP3 of 3 dBm, an IIP2 of 44 dBm at maximum gain, and S11 of under 9 dB in a frequency range from 50 MHz to 880 MHz. The power consumption is 34.8 mW at 2.2 V and the chip area is 0.16 mm 2 .

Low-Loss Analog and Digital Reflection-Type MEMS Phase Shifters With 1 : 3 Bandwidth

IEEE Transactions on Microwave Theory and Techniques, 2004

Broad-band analog and digital reflection-type phase shifters (RTPSs), showing constant phase shif... more Broad-band analog and digital reflection-type phase shifters (RTPSs), showing constant phase shift over 1 : 3 bandwidth, have been developed using microelectromechanical systems (MEMS) technology. Two-unit RTPSs centered at two different frequencies have been cascaded to achieve flat phase responses over a wide frequency band. Each phase shifter uses air-gap overlay coplanar-waveguide couplers for low-loss 3-dB coupling and bridge-type MEMS capacitors for reflective terminations. The fabricated analog phase shifter shows the average insertion loss of 3.5 dB, and maximum phase error of 4.9 from 15 to 45 GHz. The 2-bit digital RTPS shows reduced maximum phase error of 2.8 together with a comparable insertion loss of 3.1 dB from 5 to 15 GHz. The details of the circuit design, analysis, and fabrication procedures are presented together with the measurement results. Compared with the similar constant phase shifters using semiconductor diodes and transistors, the micromachined RTPS of this study shows superior performance in terms of phase errors, insertion losses, and bandwidth. Index Terms-Broad-band, microelectromechanical systems (MEMS) variable capacitor, micromachining technology, phase shifter. I. INTRODUCTION R ADIO-FREQUENCY (RF) microelectromechanical systems (MEMS) technologies have been successfully applied to the development of low-loss RF switching devices and variable capacitors [1], [2]. RF MEMS capacitive switches and variable capacitors have demonstrated significant performance advantages over the conventional electrical p-in diodes and varactors in terms of lower loss, lower parasitics, and higher linearity. Due to these advantages, they have been enabling components for a low-loss phase shifter, which is a critical circuit for modern radar and communications systems. A number of micromachined phase shifters using MEMS technology have been developed for active phased-array antennas [3], [4]. These phase shifters are based on either distributed loaded lines or switched lines and, thus, exhibit linear relationship between the relative phase shift and frequency.

Antenna for enhancing bandwidth and electronic device having the same

Antenna and Electronic Equipment Having the Same

6-18 GHz MMIC Drive and Power Amplifiers

Journal of Semiconductor Technology and Science

ABSTRACT

Novel micromachined CPW transmission lines for application in millimeter-wave circuits

Digest of Papers Microprocesses and Nanotechnology 2000. 2000 International Microprocesses and Nanotechnology Conference (IEEE Cat. No.00EX387), 2000

V-band low-loss and low-voltage distributed MEMS digital phase shifter using metal-air-metal capacitors

2002 IEEE MTT-S International Microwave Symposium Digest (Cat. No.02CH37278), 2002

A low-loss digital distributed phase shifter has been developed using micromachined capacitive sh... more A low-loss digital distributed phase shifter has been developed using micromachined capacitive shunt switches for V-band communication system. Instead of conventional MIM (metal-insulator-metal) capacitors, high-Q MAM (metal-air-metal) capacitors were used in series with the MEMS shunt capacitive switches to minimize the dielectric loss. The operation voltage for the phase shifter was also reduced by applying the bias directly to the MEMS shunt switches through choke spiral inductors. The fabricated 2-bit (270°) distributed phase shifter showed low average insertion loss of 2.2 dB at 60 GHz. The return loss is better than 10 dB over a wide frequency range from 40 to 70 GHz. The circuit operates at 15-20 V bias voltages. This phase shifter is very promising for the integrated circuits at V-band requiring low loss and good return loss over a broad band.

A 15-to-45 GHz low-loss analog reflection-type MEMS phase shifter

IEEE MTT-S International Microwave Symposium Digest, 2003, 2003

A low-loss broadband reflection-type phase shifter (RTPS), showing constant phase shift from 15 t... more A low-loss broadband reflection-type phase shifter (RTPS), showing constant phase shift from 15 to 45 GHz, was developed using MEMS technology. The analog phase shifter consists of two cascaded reflection-type phase shifters for 1:3 bandwidth. Air-gap overlay CPW couplers were employed for low-loss 3 dB coupling, and bridge-type MEMS variable capacitors were used for low-loss reflective terminations. The fabricated phase

A V-band CPS distributed analog MEMS phase shifter

IEEE MTT-S International Microwave Symposium Digest, 2003, 2003

ABSTRACT

A Micromachined Millimeter Wave Phase Shifter Using Semi-Lumped Elements

Transducers ’01 Eurosensors XV, 2001

This paper demonstrates a surface micromachined millimeter wave phase shifter with small size and... more This paper demonstrates a surface micromachined millimeter wave phase shifter with small size and large phase shift per line loss using semi-lumped elements transmission structure. The multi-pole phase shifter can be easily fabricated by cascading the unit cell. The unit cell of the phase shifter is composed of the high impedance center signal line and bridge type variable capacitors. The variable capacitors are suspended 2 over the plate connected to the both sides of the signal line to reduce the unit cell length, resulting in high phase shift per line length. The measured pull-in voltage of the variable capacitor is 50 V. The fabricated phase shifter shows high phase shift per loss (76.2 ¶/dB) as well as the high phase shift per line length (25.3 ¶/mm) at 50 GHz with the applied DC bias of 45 V.

Millimeter-wave micromachined tunable filters

1999 IEEE MTT-S International Microwave Symposium Digest (Cat. No.99CH36282), 1999

Novel types of mm-wave tunable filters using micromachined variable capacitors are presented. In ... more Novel types of mm-wave tunable filters using micromachined variable capacitors are presented. In order to demonstrate this concept, two bandpass filters, one with 2-pole lumped elements and the other with 2- pole resonators are designed at Ka-band and fabricated using MEMS technology. With applied bias, the center frequency shift as much as 1.1 GHz (4.2 %) at 26.6 GHz, and 0.8 GHz (2.5 YO) at 32 GHz, was measured for lumped elements and resonators filter, respectively. These results show the potentials of micromachined tunable filters for low cost, highly integrated transmitter and receiver for mm-wave multi band communication systems.

Wide-band CMOS loop-through amplifier for Cable TV tuner

2008 IEEE Radio Frequency Integrated Circuits Symposium, 2008

A fully integrated loop-through amplifier (LTA) for cable TV tuner is presented in a 0.18 mum CMO... more A fully integrated loop-through amplifier (LTA) for cable TV tuner is presented in a 0.18 mum CMOS process. It covers the whole frequency band from 48 MHz to 860 MHz and allows a second TV and multiple tuners. This circuit employs a parallel connection of common-gate and common-source (CG-CS) amplifiers for broadband matching. The performances are enhanced by current amplification