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Jong-Eun Jang,
Hoon Lee,
Seung-Wan Choi,
Karam Ahn,
Myoung-Sub Jung,
Eui-Seok Song, Juno Kim,
Hyoung-Hwan Ron,
Gi-Beom Kim,
Sung-Woo Bae,
Ha-Ryoung Oh,
Yeong-Rak Seong,
Jun-Seok Park
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ABSTRACT: A fully integrated 900-MHz direct-conversion transceiver for mobile RFID system is presented. The transceiver consists of a low noise amplifier, a down-conversion mixer, a band pass filter, and programmable gain amplifier (PGA) for RX path; and a power amplifier, an up-conversion mixer, a low-pass filter, and a PGA for TX path. In addition, the fractional N PLL is integrated to cover different frequency standards for different nations. The transceiver meets the dense reader environment specifications.
Radio Frequency Integrated Circuits (RFIC) Symposium, 2007 IEEE; 07/2007
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ABSTRACT: In this paper, the novel design formula is proposed for the design
of a hairpin type coupled-line bandpass filter, which has arbitrary
coupled-line lengths and image impedance. Employing the derived design
formula promotes convenience in designing and implementing the hairpin
type coupled-line bandpass filter. Measured results on fabricated
hairpin type coupled-line bandpass filters including a duplexer show
good agreements with theoretical results
Microwave Symposium Digest, 2001 IEEE MTT-S International; 02/2001
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ABSTRACT: This paper reports our latest progress in developing low-loss and
low-crosstalk silicon MMIC interconnects for millimeter-wave
applications. The proposed silicon/metal/polyimide (SIMPOL) structure
based on multilayer polyimide technology is extremely effective in
reducing noise crosstalk, and also provides very low line loss, even at
the millimeter-wave regime. The measurement results of the developed
SIMPOL structures demonstrate extremely low noise crosstalk (<-40 dB)
in the entire frequency range (up to 50 GHz), which is limited by the
dynamic range of the measurement equipment, and excellent insertion loss
(<-0,25 dB/mm) up to 45 GHz. In addition, the SIMPOL concept is
applied for the first time successfully in the design and fabrication of
branch-line hybrids at millimeter-wave frequencies, 30 and 37 GHz
IEEE Transactions on Microwave Theory and Techniques 10/2000; · 1.85 Impact Factor
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ABSTRACT: A new photonic bandgap unit structure for microstrip line is
proposed. The equivalent circuit for the proposed photonic bandgap unit
structure is derived by means of three dimensional field analysis
methods. The equivalent circuit parameters are extracted by using the
circuit analysis method. By employing the extracted parameters, the
wide-band harmonic rejection low-pass filter is designed. The
experimental results show the excellent agreements with theoretical
results
Microwave Conference, 1999 Asia Pacific; 12/1999
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ABSTRACT: A novel RF interconnect configuration for high-density broad-band
mixed-signal silicon monolithic microwave integrated circuits (MMICs) is
presented. The proposed silicon-metal-polyimide (SIMPOL) structure is
based on multilayer polyimide technology with self-packaging features,
and is extremely effective in reducing the noise crosstalk as well as
overall size of MMIC chips. Moreover, since the SIMPOL interconnect can
be built on low-cost silicon substrates using standard CMOS processing
techniques, it is very cost-effective and applicable to current products
without major cost addition. Measured results of a prototype test wafer
demonstrate that the SIMPOL interconnect has reasonably low insertion
loss (0.62 dB/mm at 30 GHz), which agrees well with theoretical
prediction (0.5 dB/mm). The line loss can be reduced significantly
(<0.1 dB/mm) by a using thicker dielectric layer. The measured
crosstalk is at the same level as the background noise floor up to 30
GHz (<-60 dB), and limited primarily by imperfect termination of
idling ports in the test structure. Full-wave finite-difference
time-domain simulations indicate that SIRPOL could achieve an extremely
high level of signal isolation, above 100 dB, at frequencies up to 50
GHz or beyond
IEEE Transactions on Microwave Theory and Techniques 10/1999; · 1.85 Impact Factor
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ABSTRACT: A novel method for suppressing leakage due to parallel-plate mode
in stripline circuits using a uni-planar compact 2-D PBG lattice is
proposed and demonstrated. The leakage is suppressed by the stopband of
the PBG lattice, which is easily etched in the ground planes with
standard planar process. Good agreements between simulation and
measurement results verify the effectiveness of this novel concept which
suppresses leakage coupling by over 30 dB in the PBG stopband
Microwave Symposium Digest, 1999 IEEE MTT-S International; 02/1999
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ABSTRACT: This paper presents the authors' latest efforts to develop high
performance interconnects for mixed signal silicon MMICs in the
millimeter wave regime. The proposed silicon/metal/polyimide (SIMPOL)
interconnect is extremely effective in reducing the crosstalk noise with
low insertion loss. Measured results of a prototype test wafer
demonstrate 0.33 dB/mm insertion loss at 30 GHz, and excellent noise
isolation comparable to background noise over the entire frequency range
up to 50 GHz
Electrical Performance of Electronic Packaging, 1999; 02/1999
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ABSTRACT: A novel compact microstrip to coplanar waveguide (CPW) transition is proposed for flip-chip interconnection. Broadband performance of the transition is simulated and agrees well with measured results. A good interconnection between microstrip line on a motherboard to CPW on a flip-chip is accomplished without any vias. For 10dB return loss, the microstrip-to-CPW transition and the microstrip-to-flip-chip interconnection present 170% and 140% bandwidth, respectively.
Microwave Conference, 1998. 28th European; 11/1998
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ABSTRACT: The new coplanar waveguide (CPW) bandpass filter with an
asymmetric structure is proposed. The proposed filter is designed based
on TEM analysis technique. It has quarter wavelength CPW couplers so
that the physical dimension and radiation loss can be improved. A
compact three-pole bandpass filter is designed and fabricated to prove
the validity of the design method. The measured results show good
agreement with the simulated characteristics
Microwave Symposium Digest, 1998 IEEE MTT-S International; 07/1998
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ABSTRACT: A modified genetic algorithm, which we call the genetic algorithm
coupled with sensitivity analysis (GACS), is proposed in comparison with
the genetic algorithm (GA) and the optimization process using the design
sensitivity analysis (DSA). The GACS reduces computing time by appending
the DSA optimization process to the genetic algorithm. As an example, a
waveguide T-junction is designed for the purpose of minimizing the
reflected power. As an analysis tool the two dimensional vector finite
element method (VFEM), which does not generate spurious solutions having
a fatal effect on the optimization process, is used. The reflected power
of the T-junction designed by the GACS shows a characteristic of less
than -20 dB near 2.2 GHz and the T-junction designed by GA also shows
similar characteristics. However the one designed by DSA optimization
shows a considerably worse performance than those of the T-junction
designed by the GACS or the GA process. The validity of the proposed
algorithm is verified through experiment
IEEE Transactions on Magnetics 06/1996; · 1.36 Impact Factor
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ABSTRACT: A microwave device is usually designed by repeated trial and error
until its performance satisfies its design goal. Numerical analysis has
been applied to predict the performance of the microwave device.
Numerical analysis gives the accurate performance of the device even
though the shape of the device is complicated. However, the numerical
analysis gives merely the performance not the designed shape of the
device. Thus, designing using numerical analysis is usually performed as
follows: many models are analyzed by changing the shapes. Among them,
the best one is adopted. This method is not efficient when the design
variables are multiple. Therefore, it is desirable to develop a more
systematic design algorithm. The optimization algorithm proposed in the
paper is the genetic algorithm (GA) coupled with the design sensitivity
analysis, which the authors call GACS. The proposed algorithm can
overcome the demerits of GA and design sensitivity analysis. The
drawback is that it needs a huge computing time, especially when it is
applied with finite element analysis. The demerit of sensitivity
analysis is that it is not suitable when the problem has multiple local
minima. The usefulness of the proposed optimization algorithm, GACS, is
verified through the simulations and experiments
Antennas and Propagation Society International Symposium, 1995. AP-S. Digest; 07/1995
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ABSTRACT: A novel compact microstrip to coplanar waveguide (CPW) transition is proposed for flip-chip interconnection. Broadband performance of the transition is simulated and agrees well with measured results. A good interconnection between microstrip line on a motherboard to CPW on a flip-chip is accomplished without any vias. For 10dB return loss, the microstrip-to-CPW transition and the microstrip-to-flip-chip interconnection present 170% and 140% bandwidth, respectively.
