Jinho Jeong - Academia.edu (original) (raw)
Papers by Jinho Jeong
IEEE Access, 2020
In this paper, a W-band mixer integrated circuit (IC) with high image rejection ratio (IRR) is pr... more In this paper, a W-band mixer integrated circuit (IC) with high image rejection ratio (IRR) is presented, compensating for the amplitude and phase mismatches between the I and Q channels in the image rejection mixer (IRM) using RF buffer amplifiers. It is shown by analysis and simulation that the signal coupling between the I and Q channels in the IRM can generate mismatches which can severely degrade the IRR, even though other circuit components are symmetrically designed so as not to induce mismatches. The coupling between two channels can become serious, especially in millimeter-wave IRM ICs where the circuit components are laid out in close proximity to reduce the chip size. It is also shown that poor isolation of millimeter-wave couplers can seriously degrade IRR. In this work, we employ an RF buffer amplifier at the RF port of the resistive mixer to compensate for the amplitude and phase mismatches. The designed W-band IRM IC is fabricated in a 0.1-μm GaAs pHEMT process. Measurements show that the bias tuning of the RF buffer amplifiers can minimize the mismatches and improve the IRR by up to 35 dB at RF from 91 to 95 GHz at an IF of 50 MHz. The IRM exhibits an IRR of 19.2-47.9 dB with conversion loss of 7.9-9.2 dB, which belongs to the highest IRR among the reported IRMs in the W-band.
Electronics Letters, 2018
A frequency-selective limiter (FSL) using an injection locked oscillator (ILO) is proposed for a ... more A frequency-selective limiter (FSL) using an injection locked oscillator (ILO) is proposed for a blocker cancellation, which employs an ILO in the feedforward path as a high-Q notch filter to select and amplify the blocker from the input signal. The ILO also functions as a phase shifter providing a proper phase delay so that two blockers in the feedforward and thru paths cancel each other out in the combining node. The proposed FSL is fabricated in a commercial 0.15 μm GaAs pHEMT process with a maximum blocker suppression of 27 dB in the 50 MHz spacing two-tone measurement at the K-band. Thus, it provides a blocker suppression higher than 20 dB over the 250 MHz blocker bandwidth.
33rd European Microwave Conference, 2003, 2003
An injection-locked push-push oscillator at V-band is developed for high purity millimeter-wave s... more An injection-locked push-push oscillator at V-band is developed for high purity millimeter-wave signal source. Cross-coupled HEMTs are applied for the negative resistance generation across wide frequency range and virtually grounded short-ended lines are used for the resonant circuit instead of lumped inductors. Thanks to the differential operation of cross-coupled HEMTs, the pushpush oscillator was easily implemented by combing the 2 nd harmonics of oscillation signal at the drain terminals. Injection signal at the fundamental oscillation frequency is applied at the gate of current source FET of cross-coupled FETs for stabilizing the oscillation, which performs the amplification and harmonic generation. The designed oscillator was fabricated using 0.15µm GaAs pHEMT process. The measurement showed the free-running oscillation around 35.8 GHz and the maximum lock range of 1.48 GHz (2.1%) around 71.6 GHz with the average output power of-6 dBm.
IEEE Transactions on Terahertz Science and Technology, 2015
In this paper, H-band (220-325 GHz) power amplifier (PA) integrated circuits (ICs) are presented ... more In this paper, H-band (220-325 GHz) power amplifier (PA) integrated circuits (ICs) are presented using 250-nm InP HBT technology, where a cascode topology was adopted to achieve high gain and high output power. Three PAs were designed: PA1 was implemented with two-stage cascode HBTs, PA2 combined two PA1s, and PA3 combined four PA1s, by using Wilkinson couplers without isolation resistors. Electromagnetic simulations were carried out for the accurate design of passive circuits such as a microstrip line, a capacitor, and RF pads. The measured insertion loss of the RF pad and Wilkinson coupler was as low as 0.24 dB and 0.70 dB, respectively, at 300 GHz. The three PAs exhibited a measured gain higher than 15 dB with good return losses at 300 GHz. The output powers scaled well with total emitter area of the PAs. PA3 exhibited a maximum output power of 13.5 dBm at 301 GHz. To the best of the authors' knowledge, this corresponds to the highest output power among the previously reported solid-state PAs in this frequency range.
2000 IEEE MTT-S International Microwave Symposium Digest (Cat. No.00CH37017), 2000
Abstract A 1.6 W power amplifier module was developed at 24 GHz using a waveguide-based power com... more Abstract A 1.6 W power amplifier module was developed at 24 GHz using a waveguide-based power combiner. The combiner is based on a double antipodal finline-to-microstrip transition structure which also serves as a two-way power combiner. Back-to-back ...
Microwave and Optical Technology Letters, 2009
curves versus frequency with different truncated term of Floquet harmonics are given. It can be f... more curves versus frequency with different truncated term of Floquet harmonics are given. It can be found that our methods can converge with m ϭ n ϭ 30. When the incident angle is i ϭ 30°, i ϭ 0°, the double-screen octagon FSS is again analyzed. As shown in Figure 8, the transmission loss curves versus frequency are compared between in our method and commercial software designer. As shown in Figure 9, the transmission loss curves versus frequency with different truncated term of Floquet harmonics are given. It can be found that our methods can converge with m ϭ n ϭ 30. 4. CONCLUSIONS In this article, spectral domain MoM with RWG basis functions is presented for fast calculation of FSS in layered media with arbitrarily shaped metal geometry. Several examples are calculated and the numerical results demonstrate the efficiency of the presented method.
Microwave and Optical Technology Letters, 2007
Load impedance modulation and gate bias control were investigated to improve the performance of W... more Load impedance modulation and gate bias control were investigated to improve the performance of W‐CDMA base‐station envelope tracking amplifiers by means of simulations based on the measured data of a 10‐W GaAs FET power amplifier. It is shown that adapting the load impedance along with the drain bias voltage can effectively improve the average efficiency of envelope tracking amplifier. The improvement becomes more apparent in the operating regime of power back‐off. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 1954–1957, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22566
Microwave and Optical Technology Letters, 2012
A broadband watt‐level power amplifier in a metamorphic high electron mobility transistor (mHEMT)... more A broadband watt‐level power amplifier in a metamorphic high electron mobility transistor (mHEMT) technology is presented at K‐band. The quadruple‐stacked transistor is used to overcome the low breakdown voltage limit of mHEMTs and achieve watt‐level output powers. The fabricated power amplifier using 130‐nm mHEMTs shows an output power of 1.3 W at 18 GHz with a 3‐dB power bandwidth of 58%. To the best of our knowledge, this is the first report of watt‐level single‐chip power amplifiers in mHEMT technology. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2624–2626, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27140
IEICE Electronics Express, 2012
A new digital predistortion (DPD) technique is presented for the linearization of RF power amplif... more A new digital predistortion (DPD) technique is presented for the linearization of RF power amplifiers (PAs) for wideband orthogonal frequency division multiplexing (OFDM) signals. The proposed DPD technique employs the phase correction term to compensate for the frequency dependent AM-PM distortion of PAs, considering the wide bandwidth of OFDM signal. The simulation shows that the proposed DPD technique can significantly improve the error vector magnitude (EVM) performance of RF PAs.
IEICE Electronics Express, 2011
In this paper, we present two-way and four-way power dividers that operate in wideband over K-ban... more In this paper, we present two-way and four-way power dividers that operate in wideband over K-band. To maximize the integrability with other circuit blocks, the power dividers are designed in a purely digital CMOS technology without any RF back-end-of-line process. We discuss a design issue arising from the high loss of transmission lines in the digital process. A capacitor-loaded Wilkinson topology is adopted for a compact size. The proposed dividers are implemented in a 0.13-μm digital CMOS process with automatic dummy metal fills. We also analyze the effect of the dummy fills on the power divider performance, showing good agreement with measured results.
IEEE Transactions on Microwave Theory and Techniques, 2004
In this paper, active control schemes are presented to optimize the performance of the distribute... more In this paper, active control schemes are presented to optimize the performance of the distributed amplifier (DA) subject to the process variation. A detailed analysis of the DA with mismatched termination loads has been performed, which reveals that pronounced gain and group-delay ripple arises at the low-frequency end from the reflected waves in the artificial transmission line. To solve this problem, an active variable resistor is proposed as the gate-line termination load. The gain and stability of the cascode DA has also been analyzed, which identifies the most critical component determining the tradeoff between the gain-bandwidth product (GBP) and the stability to be the gate feedback resistor of common-gate field-effect transistor. It is also replaced with the active resistor to maximize GBP, while avoiding oscillations. A nine-section cascode DA with active control features is designed and fabricated using commercial GaAs pseudomorphic high electron-mobility transistor foundry. The measurement shows that the gain and group-delay ripple can be minimized, and GBP can be maximized without oscillations by the active bias controls. Active control schemes allow the monolithic DAs to be fine tuned after the fabrication and, thus, can be a robust DA design methodology against process variation and inaccurate device models. Index Terms-Cascode field-effect transistor (FET), distributed amplifier (DA), high electron-mobility transistor (HEMT), monolithic microwave integrated circuit (MMIC).
IEEE Transactions on Microwave Theory and Techniques, 2010
... [13] S. Pornpromlikit, J. Jeong, CD Presti, A. Scuderi, and PM As-beck, A 33-dBm 1.9-GHz sil... more ... [13] S. Pornpromlikit, J. Jeong, CD Presti, A. Scuderi, and PM As-beck, A 33-dBm 1.9-GHz silicon-on-insulator CMOS stacked-FET power amplifier, in IEEE MTT-S Int. Microw. Symp. ... 2007. [17] FH Raab, Maximum efficiency and output of class-F power amplifiers, IEEE Trans. ...
IEEE Transactions on Microwave Theory and Techniques, 2006
... Base-Station Amplifier Using GaN HFETs Donald F. Kimball, Member, IEEE, Jinho Jeong, Member, ... more ... Base-Station Amplifier Using GaN HFETs Donald F. Kimball, Member, IEEE, Jinho Jeong, Member, IEEE, Chin Hsia, Paul Draxler, Member, IEEE, Sandro Lanfranco, Walter Nagy, Kevin Linthicum, Lawrence E. Larson, Fellow, IEEE, and Peter M. Asbeck, Fellow, IEEE ...
IEEE Transactions on Microwave Theory and Techniques, 2005
In this paper,-band high-order frequency divider monolithic microwave integrated circuits (MMICs)... more In this paper,-band high-order frequency divider monolithic microwave integrated circuits (MMICs) showing wide bandwidth and low-power dissipation are presented. For high-order (divide-by-four) frequency division, a super-harmonic signal is injected into a self-oscillating subharmonic mixer loop consisting of cascode field-effect transistors (FETs). Cascode FET-based harmonic injection locking allows high-frequency operation, simple circuit configuration, reduced FET count, and thus, low dc power consumption. Bias circuits and quarter-wavelength stubs are used to effectively suppress unwanted harmonic and spurious signals in the oscillation loop. A simple analysis method employing two-tone harmonic-balance simulation and an ideal directional coupler is developed to optimize the performance of the high-order divider. The designed-band frequency dividers are fabricated with a commercial 0.15-m GaAs pseudomorphic high electron-mobility transistor foundry. The measurement of a divide-by-four MMIC shows a bandwidth of 2.81 GHz around 64.0 GHz under very small dc power consumption of 7.5 mW. The circuit concept has been extended to a divide-by-five MMIC by adding a frequency doubler in the feedback loop, which shows the bandwidth of 1.02 GHz at-band. To the best of our knowledge, the frequency dividers of this study show the best performance in terms of division order and dc power consumption among the reported millimeter-wave analog frequency dividers at-band and above. Index Terms-Cascode field-effect transistor (FET), frequency divider, injection-locking oscillator, millimeter wave, monolithic microwave integrated circuit (MMIC). I. INTRODUCTION A MICROWAVE and millimeter-wave frequency divider is a key component to implement phase-locked loops (PLLs) at high frequencies [1]. For low-cost and high-performance millimeter-wave applications, high division order and wide bandwidth are required together with low dc power consumption. Digital frequency divider is capable of providing high division orders across a wide bandwidth [2]-[4], but it requires high-speed devices for millimeter-wave operation since the maximum operating frequency is determined by the current gain cutoff frequency of the active devices.
Electronics Letters, 2003
A V-band high-efficiency power-combining module was developed using double antipodal finline stru... more A V-band high-efficiency power-combining module was developed using double antipodal finline structures. The combiner performs the dual functionality of power combining and mode transition from microstrip to waveguide. The measurement of the back-to-back connected combiner demonstrated an insertion loss of 1.2 dB and return loss better than 15 dB around 60 GHz with a 3 dB bandwidth of 18 GHz. The power-combining module incorporating two MMIC power amplifiers demonstrated a combining efficiency higher than 80%.
Microwave and Optical Technology Letters, 2007
2⌬ 2. (3) 2.3. Frequency Doubler The differential output of the VCO is directly connected to the ... more 2⌬ 2. (3) 2.3. Frequency Doubler The differential output of the VCO is directly connected to the frequency doubler input. The frequency doubler consists of clipping transistors and inductor loads, as shown in Figure 2 [1]. The input of the pinch-off clipping transistors need large swing signals with a lower d.c. level. However, the input of the clipper has high impedance since a common source stage has high input impedance and the low miller capacitance due to low load impedance of the clipper. 3. MEASUREMENT RESULTS frequency doubler in 0.18 m CMOS for 24 GHz applications, IEEE (2006). 7. C. Cao and K.O. Kenneth, Millimeter-wave voltage-controlled oscillators in 0.13-m CMOS technology, IEEE J Solid-State Circuits 41 (2006), 1297-1304.
IEEE Access, 2020
In this paper, a W-band mixer integrated circuit (IC) with high image rejection ratio (IRR) is pr... more In this paper, a W-band mixer integrated circuit (IC) with high image rejection ratio (IRR) is presented, compensating for the amplitude and phase mismatches between the I and Q channels in the image rejection mixer (IRM) using RF buffer amplifiers. It is shown by analysis and simulation that the signal coupling between the I and Q channels in the IRM can generate mismatches which can severely degrade the IRR, even though other circuit components are symmetrically designed so as not to induce mismatches. The coupling between two channels can become serious, especially in millimeter-wave IRM ICs where the circuit components are laid out in close proximity to reduce the chip size. It is also shown that poor isolation of millimeter-wave couplers can seriously degrade IRR. In this work, we employ an RF buffer amplifier at the RF port of the resistive mixer to compensate for the amplitude and phase mismatches. The designed W-band IRM IC is fabricated in a 0.1-μm GaAs pHEMT process. Measurements show that the bias tuning of the RF buffer amplifiers can minimize the mismatches and improve the IRR by up to 35 dB at RF from 91 to 95 GHz at an IF of 50 MHz. The IRM exhibits an IRR of 19.2-47.9 dB with conversion loss of 7.9-9.2 dB, which belongs to the highest IRR among the reported IRMs in the W-band.
Electronics Letters, 2018
A frequency-selective limiter (FSL) using an injection locked oscillator (ILO) is proposed for a ... more A frequency-selective limiter (FSL) using an injection locked oscillator (ILO) is proposed for a blocker cancellation, which employs an ILO in the feedforward path as a high-Q notch filter to select and amplify the blocker from the input signal. The ILO also functions as a phase shifter providing a proper phase delay so that two blockers in the feedforward and thru paths cancel each other out in the combining node. The proposed FSL is fabricated in a commercial 0.15 μm GaAs pHEMT process with a maximum blocker suppression of 27 dB in the 50 MHz spacing two-tone measurement at the K-band. Thus, it provides a blocker suppression higher than 20 dB over the 250 MHz blocker bandwidth.
33rd European Microwave Conference, 2003, 2003
An injection-locked push-push oscillator at V-band is developed for high purity millimeter-wave s... more An injection-locked push-push oscillator at V-band is developed for high purity millimeter-wave signal source. Cross-coupled HEMTs are applied for the negative resistance generation across wide frequency range and virtually grounded short-ended lines are used for the resonant circuit instead of lumped inductors. Thanks to the differential operation of cross-coupled HEMTs, the pushpush oscillator was easily implemented by combing the 2 nd harmonics of oscillation signal at the drain terminals. Injection signal at the fundamental oscillation frequency is applied at the gate of current source FET of cross-coupled FETs for stabilizing the oscillation, which performs the amplification and harmonic generation. The designed oscillator was fabricated using 0.15µm GaAs pHEMT process. The measurement showed the free-running oscillation around 35.8 GHz and the maximum lock range of 1.48 GHz (2.1%) around 71.6 GHz with the average output power of-6 dBm.
IEEE Transactions on Terahertz Science and Technology, 2015
In this paper, H-band (220-325 GHz) power amplifier (PA) integrated circuits (ICs) are presented ... more In this paper, H-band (220-325 GHz) power amplifier (PA) integrated circuits (ICs) are presented using 250-nm InP HBT technology, where a cascode topology was adopted to achieve high gain and high output power. Three PAs were designed: PA1 was implemented with two-stage cascode HBTs, PA2 combined two PA1s, and PA3 combined four PA1s, by using Wilkinson couplers without isolation resistors. Electromagnetic simulations were carried out for the accurate design of passive circuits such as a microstrip line, a capacitor, and RF pads. The measured insertion loss of the RF pad and Wilkinson coupler was as low as 0.24 dB and 0.70 dB, respectively, at 300 GHz. The three PAs exhibited a measured gain higher than 15 dB with good return losses at 300 GHz. The output powers scaled well with total emitter area of the PAs. PA3 exhibited a maximum output power of 13.5 dBm at 301 GHz. To the best of the authors' knowledge, this corresponds to the highest output power among the previously reported solid-state PAs in this frequency range.
2000 IEEE MTT-S International Microwave Symposium Digest (Cat. No.00CH37017), 2000
Abstract A 1.6 W power amplifier module was developed at 24 GHz using a waveguide-based power com... more Abstract A 1.6 W power amplifier module was developed at 24 GHz using a waveguide-based power combiner. The combiner is based on a double antipodal finline-to-microstrip transition structure which also serves as a two-way power combiner. Back-to-back ...
Microwave and Optical Technology Letters, 2009
curves versus frequency with different truncated term of Floquet harmonics are given. It can be f... more curves versus frequency with different truncated term of Floquet harmonics are given. It can be found that our methods can converge with m ϭ n ϭ 30. When the incident angle is i ϭ 30°, i ϭ 0°, the double-screen octagon FSS is again analyzed. As shown in Figure 8, the transmission loss curves versus frequency are compared between in our method and commercial software designer. As shown in Figure 9, the transmission loss curves versus frequency with different truncated term of Floquet harmonics are given. It can be found that our methods can converge with m ϭ n ϭ 30. 4. CONCLUSIONS In this article, spectral domain MoM with RWG basis functions is presented for fast calculation of FSS in layered media with arbitrarily shaped metal geometry. Several examples are calculated and the numerical results demonstrate the efficiency of the presented method.
Microwave and Optical Technology Letters, 2007
Load impedance modulation and gate bias control were investigated to improve the performance of W... more Load impedance modulation and gate bias control were investigated to improve the performance of W‐CDMA base‐station envelope tracking amplifiers by means of simulations based on the measured data of a 10‐W GaAs FET power amplifier. It is shown that adapting the load impedance along with the drain bias voltage can effectively improve the average efficiency of envelope tracking amplifier. The improvement becomes more apparent in the operating regime of power back‐off. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 1954–1957, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22566
Microwave and Optical Technology Letters, 2012
A broadband watt‐level power amplifier in a metamorphic high electron mobility transistor (mHEMT)... more A broadband watt‐level power amplifier in a metamorphic high electron mobility transistor (mHEMT) technology is presented at K‐band. The quadruple‐stacked transistor is used to overcome the low breakdown voltage limit of mHEMTs and achieve watt‐level output powers. The fabricated power amplifier using 130‐nm mHEMTs shows an output power of 1.3 W at 18 GHz with a 3‐dB power bandwidth of 58%. To the best of our knowledge, this is the first report of watt‐level single‐chip power amplifiers in mHEMT technology. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2624–2626, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27140
IEICE Electronics Express, 2012
A new digital predistortion (DPD) technique is presented for the linearization of RF power amplif... more A new digital predistortion (DPD) technique is presented for the linearization of RF power amplifiers (PAs) for wideband orthogonal frequency division multiplexing (OFDM) signals. The proposed DPD technique employs the phase correction term to compensate for the frequency dependent AM-PM distortion of PAs, considering the wide bandwidth of OFDM signal. The simulation shows that the proposed DPD technique can significantly improve the error vector magnitude (EVM) performance of RF PAs.
IEICE Electronics Express, 2011
In this paper, we present two-way and four-way power dividers that operate in wideband over K-ban... more In this paper, we present two-way and four-way power dividers that operate in wideband over K-band. To maximize the integrability with other circuit blocks, the power dividers are designed in a purely digital CMOS technology without any RF back-end-of-line process. We discuss a design issue arising from the high loss of transmission lines in the digital process. A capacitor-loaded Wilkinson topology is adopted for a compact size. The proposed dividers are implemented in a 0.13-μm digital CMOS process with automatic dummy metal fills. We also analyze the effect of the dummy fills on the power divider performance, showing good agreement with measured results.
IEEE Transactions on Microwave Theory and Techniques, 2004
In this paper, active control schemes are presented to optimize the performance of the distribute... more In this paper, active control schemes are presented to optimize the performance of the distributed amplifier (DA) subject to the process variation. A detailed analysis of the DA with mismatched termination loads has been performed, which reveals that pronounced gain and group-delay ripple arises at the low-frequency end from the reflected waves in the artificial transmission line. To solve this problem, an active variable resistor is proposed as the gate-line termination load. The gain and stability of the cascode DA has also been analyzed, which identifies the most critical component determining the tradeoff between the gain-bandwidth product (GBP) and the stability to be the gate feedback resistor of common-gate field-effect transistor. It is also replaced with the active resistor to maximize GBP, while avoiding oscillations. A nine-section cascode DA with active control features is designed and fabricated using commercial GaAs pseudomorphic high electron-mobility transistor foundry. The measurement shows that the gain and group-delay ripple can be minimized, and GBP can be maximized without oscillations by the active bias controls. Active control schemes allow the monolithic DAs to be fine tuned after the fabrication and, thus, can be a robust DA design methodology against process variation and inaccurate device models. Index Terms-Cascode field-effect transistor (FET), distributed amplifier (DA), high electron-mobility transistor (HEMT), monolithic microwave integrated circuit (MMIC).
IEEE Transactions on Microwave Theory and Techniques, 2010
... [13] S. Pornpromlikit, J. Jeong, CD Presti, A. Scuderi, and PM As-beck, A 33-dBm 1.9-GHz sil... more ... [13] S. Pornpromlikit, J. Jeong, CD Presti, A. Scuderi, and PM As-beck, A 33-dBm 1.9-GHz silicon-on-insulator CMOS stacked-FET power amplifier, in IEEE MTT-S Int. Microw. Symp. ... 2007. [17] FH Raab, Maximum efficiency and output of class-F power amplifiers, IEEE Trans. ...
IEEE Transactions on Microwave Theory and Techniques, 2006
... Base-Station Amplifier Using GaN HFETs Donald F. Kimball, Member, IEEE, Jinho Jeong, Member, ... more ... Base-Station Amplifier Using GaN HFETs Donald F. Kimball, Member, IEEE, Jinho Jeong, Member, IEEE, Chin Hsia, Paul Draxler, Member, IEEE, Sandro Lanfranco, Walter Nagy, Kevin Linthicum, Lawrence E. Larson, Fellow, IEEE, and Peter M. Asbeck, Fellow, IEEE ...
IEEE Transactions on Microwave Theory and Techniques, 2005
In this paper,-band high-order frequency divider monolithic microwave integrated circuits (MMICs)... more In this paper,-band high-order frequency divider monolithic microwave integrated circuits (MMICs) showing wide bandwidth and low-power dissipation are presented. For high-order (divide-by-four) frequency division, a super-harmonic signal is injected into a self-oscillating subharmonic mixer loop consisting of cascode field-effect transistors (FETs). Cascode FET-based harmonic injection locking allows high-frequency operation, simple circuit configuration, reduced FET count, and thus, low dc power consumption. Bias circuits and quarter-wavelength stubs are used to effectively suppress unwanted harmonic and spurious signals in the oscillation loop. A simple analysis method employing two-tone harmonic-balance simulation and an ideal directional coupler is developed to optimize the performance of the high-order divider. The designed-band frequency dividers are fabricated with a commercial 0.15-m GaAs pseudomorphic high electron-mobility transistor foundry. The measurement of a divide-by-four MMIC shows a bandwidth of 2.81 GHz around 64.0 GHz under very small dc power consumption of 7.5 mW. The circuit concept has been extended to a divide-by-five MMIC by adding a frequency doubler in the feedback loop, which shows the bandwidth of 1.02 GHz at-band. To the best of our knowledge, the frequency dividers of this study show the best performance in terms of division order and dc power consumption among the reported millimeter-wave analog frequency dividers at-band and above. Index Terms-Cascode field-effect transistor (FET), frequency divider, injection-locking oscillator, millimeter wave, monolithic microwave integrated circuit (MMIC). I. INTRODUCTION A MICROWAVE and millimeter-wave frequency divider is a key component to implement phase-locked loops (PLLs) at high frequencies [1]. For low-cost and high-performance millimeter-wave applications, high division order and wide bandwidth are required together with low dc power consumption. Digital frequency divider is capable of providing high division orders across a wide bandwidth [2]-[4], but it requires high-speed devices for millimeter-wave operation since the maximum operating frequency is determined by the current gain cutoff frequency of the active devices.
Electronics Letters, 2003
A V-band high-efficiency power-combining module was developed using double antipodal finline stru... more A V-band high-efficiency power-combining module was developed using double antipodal finline structures. The combiner performs the dual functionality of power combining and mode transition from microstrip to waveguide. The measurement of the back-to-back connected combiner demonstrated an insertion loss of 1.2 dB and return loss better than 15 dB around 60 GHz with a 3 dB bandwidth of 18 GHz. The power-combining module incorporating two MMIC power amplifiers demonstrated a combining efficiency higher than 80%.
Microwave and Optical Technology Letters, 2007
2⌬ 2. (3) 2.3. Frequency Doubler The differential output of the VCO is directly connected to the ... more 2⌬ 2. (3) 2.3. Frequency Doubler The differential output of the VCO is directly connected to the frequency doubler input. The frequency doubler consists of clipping transistors and inductor loads, as shown in Figure 2 [1]. The input of the pinch-off clipping transistors need large swing signals with a lower d.c. level. However, the input of the clipper has high impedance since a common source stage has high input impedance and the low miller capacitance due to low load impedance of the clipper. 3. MEASUREMENT RESULTS frequency doubler in 0.18 m CMOS for 24 GHz applications, IEEE (2006). 7. C. Cao and K.O. Kenneth, Millimeter-wave voltage-controlled oscillators in 0.13-m CMOS technology, IEEE J Solid-State Circuits 41 (2006), 1297-1304.