Search

The world’s first single-chip RF transceiver to support 5G sub-6-GHz new radio (NR) and long-term evolution (LTE) E-UTRA New Radio-Dual Connectivity (EN-DC) in 14-nm FinFET CMOS technology is presented. The single-chip transceiver integrates identical primary and diversity receivers (RXs) with seven pipelines for supporting four inter-band carrier aggregation (CA) with three 4 $\times $ 4 MIMO, two independent transmitter (TX) chains, eight frequency synthesizers for RX and TX, and on-chip digitally controlled crystal oscillator (DCXO) to reduce the phase noise and bill of material (BOM) cost. The receiver features 12 single-ended low-noise amplifiers (LNAs) with wideband characteristics. With the help of the proposed pipeline structure and frequency-band switchable transformer, the die size can be reduced despite covering the whole frequency range from 2G to sub-6-GHz 5G NR. It achieves the noise figure (NF) from 6.5 to 9.3 dB, +3-dBm out-of-band (OOB) IIP3, more than +70-dBm OOB IIP2 after calibration. For the transmitter, low RX-band noise and harmonic suppression technique are applied to support surface acoustic wave (SAW)-less architecture, and the bandwidth control of the baseband filter is implemented for the digital pre-distortion (DPD) operation of 100-MHz BW in NR transmit data. The measured error vector magnitudes (EVMs) in 4G and 5G bands of n79 are −39.5 dB at +4-dBm output power and −33.9 dB at +3.06-dBm output power, respectively, and the measured RX-band noise of 2G is −163 dBc at 20-MHz offset. The RX consumes 18 mW at LTE 1-CA mode and the TX consumes 350 mW at n79.

Signage systems are visual information systems that indicate the direction, allow for identification, and show safety information and regulations to occupants via graphics or text during emergencies. Wayfinding is difficult in large and complex buildings, such as large shopping malls. Occupants can be disoriented while searching for their way in such buildings. This problem can be more serious in emergency situations, such as fires, than in normal situations. Signage systems can be helpful in solving this problem. Domestic and overseas standards on emergency signage systems specify that the signage should be noticeable, easy to read, and easy to understand. However, most regulations do not quantify the effectiveness of such signage systems under emergency situations. To address these issues, in this study, several experiments were conducted considering the viewing distance and angle using a backlit signage system, and changes in cognition under smoke conditions were analyzed. First, the concept of effective cognition area (ECA) was introduced to analyze the relationship between the viewing distance and angle. Experiments were conducted using a backlit emergency exit sign, and the changes in the ECA in a smoke situation were analyzed. Finally, the results of this study were compared with those of previous studies. Furthermore, the extent to which occupants can recognize the signage system was quantified. If the concept of ECA developed in this study is applied to the development of emergency signage design, more diverse evacuation scenarios could be designed.

This paper presents a wide dynamic range (DR) CMOS root-mean-square power detector with a temperature variation compensation technique in a 28-nm CMOS process. The cascaded gain amplifiers and squaring circuits in the proposed power detector can achieve wide DR with the power level segmented detection method using a switch driver with the help of a modem. A 12-bit current digital-to-analog converter is used to calibrate dc offset in the power detector with 25- $\mu{\hbox{V}}$ steps to improve the accuracy. Measured DR is more than 40 dB from 700 MHz to 4 GHz. A temperature compensation bias circuit improves the performance of the detector with maximum 0.8-dB error over the temperature range $-{\hbox{30 }}^{\circ}{\hbox{C}}\sim {\hbox{90 }}^{\circ}{\hbox{C}}$ . The chip area is 333 $ \mu{\hbox{m}}\times$ 450 $\mu{\hbox{m}}$ and the power consumption is from 5.8 to 11.8 mW depending on the input power using a 1.8-V power supply.

As LTE offers the best wireless experience as never before, people spend much more time on smartphones to enjoy internet surfing and social networking, etc. To further improve the LTE network efficiency, recently, the Power-Class 2 (PC2) High Power User Equipment (HPUE) applied to B41 is deployed. To support HPUE, RF transmitters (TXs) need to deliver higher output power while maintaining stringent linearity requirements of emission mask, especially for third-order Counter Intermodulation (CIM3) in one Resource Block (1RB) case. CIM3 can be improved by several techniques such as power mixers [1,2], Harmonic-Reject Mixers (HRM) [3], notch-filter mixers [4, 5] and digital TXs [6]. Power-mixer, HRM and digital TX solutions may not be suitable for HPUE due to power-efficiency limitations. The notch-filter mixer is based on a voltage-mode passive mixer with 25%-duty-cycle LO, and it reduces 3flo, which exactly corresponds to the component at 3flo-fbb, by employing an LC trap. However, the conventional series [4] or parallel [5] 3flo trap causes a significant insertion loss at flo, which exactly corresponds to the component at flo+fbb, due to the trade-off between its efficiency, 3flo suppression and tuning range. This work presents a new transformer-based notch filter mixer. In this structure, the 3flo suppression can automatically track the channel frequency resulting in a wide operation frequency range of 1.4GHz to 2.7GHz while both the power efficiency and 3flo suppression are improved compared with the conventional notch-filter mixer [4,5].

Objectives : The purpose of this study is to explore the trends of acupoints used for lumbar HIVD(Herniated Intervertebral Disc) and treatment and anatomical location of Hwatahyeopcheock. Methods : We searched the latest clinical studies on acupuncture treatment for lumbar HIVD(Herniated Intervertebral Disc) through domestic studies search. To analyze the data, we categorized them by year and article types of literatures and investigated often-used acupoints and acupuncture types for treatment by reading treatment part of every paper searched. Domestic and Chinese literatures related to Hwatahyeopcheock were also studied for its anatomical location. Results : Total 50 articles are searched and local points are more used than distant points for lumbar HIVD(Herniated Intervertebral Disc) and most of them showed curative effects. Back-su points were used the most and Hwatahyeopcheock use accounted for one-third of the articles. In the articles of Hwatahyeopcheock use, except for one, patients complained of both low back pain and radiating pain, and all of them showed positive results after treatment. Conclusions : Back su point is considered to have its meaning as physical region where patients feel pain including herniated disc level rather than the effect meridian system makes. Through document research and meridian muscle theory, we found that Hwatahyeopcheock means vertebral facet joint, intervertebral foramen and surrounding muscle, nerve, blood vessel and related spinal nerves.

This paper presents a wideband transformer-coupled CMOS power amplifier (PA). On-chip transmission-line transformers are used as key components of matching networks at output, input, and interstage. The wideband on-chip transformer is harnessed without any additional inductive devices so that a wideband power characteristic can be achieved. The PA is fabricated using a 0.18-μm CMOS process. It provides a saturated output power of 21.5 dBm with the power-added efficiency (PAE) of 20.3%, and the output 1-dB gain-compressed power (P1 dB) is 20.2 dBm with the PAE of 14.8% at 9.5 GHz, respectively. The small-signal gain is 25.3 dB and the 3-dB bandwidth is 6.5 GHz (6.5-13 GHz). The die area is 1.34 mm × 0.47 mm. Among the reported X/Ku-band CMOS PAs, this amplifier achieves the highest figure of merit, and also shows suitable performances for phased-array systems.

We present a novel dielectrophoretic technique that can be used to characterize molecular interactions inside a microfluidic device. Our approach allows functionalized beads which are initially at rest on a functionalized surface to be pulled away from the surface by the dielectrophoretic force acting on the beads. As a result, the interaction between the molecules on the surface and the beads can be quantitatively examined. We report detailed experimental results and validate the results with a model to show that the technique can be used to measure forces of interaction between molecules under various experimental conditions.

The Notch signaling pathway appears to perform an important function in inflammation. Here, we present evidence to suggest that lipopolysaccharide (LPS) suppresses Notch signaling via the direct modification of Notch by the nitration of tyrosine residues in macrophages. In the RAW264.7 macrophage cell line and in rat primary alveolar macrophages, LPS was found to inhibit Notch1 intracellular domain (Notch1-IC) transcription activity, which could then be rescued by treatment with N(G)-nitro-l-arginine, a nitric oxide synthase (NOS) inhibitor. Nitric oxide (NO), which was produced in cells that stably express endothelial NOS (eNOS) and brain NOS (bNOS), also induced the inhibition of Notch1 signaling. The NO-induced inhibition of Notch1 signaling remained unchanged after treatment with 1H-[1,2,4]oxadiazolo[4,3-alpha]quinoxalin-1-one (ODQ), a guanylyl-cyclase inhibitor, and was not found to be mimicked by 8-bromo-cyclic GMP in the primary alveolar macrophages. With regards to the control of Notch signaling, NO appears to have a significant negative influence, via the nitration of Notch1-IC, on the binding that occurs between Notch1-IC and RBP-Jk, both in vitro and in vivo. By intrinsic fluorescence, we also determined that nitration could mediate conformational changes of Notch1-IC. The substitution of phenylalanine for tyrosine at residue 1905 in Notch1-IC abolished the nitration of Notch1-IC by LPS. Overall, our data suggest that an important relationship exists between LPS-mediated inflammation and the Notch1 signaling pathway, and that this relationship intimately involves the nitration of Notch1-IC tyrosine residues.

The Notch signaling pathway appears to perform an important function in the determination of cell fate and in differentiation, in a wide variety of organisms and cell types. In this study, we provide evidence that the inactivation of Notch signaling by zinc is achieved via a PI3K-Akt-dependent, cytoplasmic retention of Notch1-IC and RBP-Jk. Extracellular zinc has been determined to inhibit constitutive active mutants of both Notch1 (DeltaEN1) and Notch1-IC-mediated transcription. However, in such cases, neither the cleavage pattern of Notch nor the protein stability of Notch1-IC and RBP-Jk was found to have significantly changed. With regard to the modulation of Notch signaling, zinc appears to exert a significant negative influence on the binding occurring between Notch1 and RBP-Jk, both in vivo and in vitro. The zinc-induced inhibition of Notch signaling can be rescued via pretreatment with wortmannin or LY294002, both of which are specific PI3K signaling pathway inhibitors. Furthermore, we ascertained that zinc triggers the cytoplasmic retention of Notch1-IC and RBP-Jk, and that cytoplasmic retention could be rescued via treatment with wortmannin. Overall, we have determined that an important relationship exists between zinc and the Notch1 signaling pathway, and that this relationship is intimately involved with the cytoplasmic retention of Notch and RBP-Jk.

A fully integrated 5-㎓ CMOS power amplifier for IEEE 802.11a WLAN applications is implemented using 0.18-㎛ CMOS technology. An on-chip transmission-line transformer is used for output matching network and voltage combining. Input balun, inter-stage matching components, output transmission line transformer and RF chokes are fully integrated in the designed amplifier so that no external components are required. The power amplifier occupies a total area of 1.7㎜ × 1.2㎜. At a 3.3-V supply voltage, the amplifier exhibits a 22.6-㏈m output 1-㏈ compression point, 23.8-㏈m saturated output power, 25-㏈ power gain. The measured power added efficiency (PAE) is 20.1% at max. peak, 18.8% at P1㏈. When 54 Mbps/64 QAM OFDM signal is applied, the PA delivers 12㏈m of average power at the EVM of -25㏈.

A 1.9-GHz CMOS differential power amplifier for polar transmitter applications is designed using a 0.25-μm RF CMOS process. The input transformer and output transformer are fully integrated on the chip. The transmission line transformer is used as an output power combiner and an output matching component. To increase the coupling factor of the transformer, an interdigitated transmission line transformer is used and it achieves a drain efficiency of 28% at the maximum output power. The maximum output power is 28.2 dBm with a 1.8-V supply voltage. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 3162–3166, 2007; Published online in Wiley InterScience (www.interscience.wiley.com).DOI 10.1002/mop.22957

This paper reports new RF microelectromechanical systems (MEMS) switches actuated by the combination of electromagnetic and electrostatic forces for low-voltage and low-power operation. The proposed RF MEMS switches have utilized the proper combination of two actuation mechanisms: taking advantage of the large actuation force from electromagnetic actuation for initial movement and the low-power feature from electrostatic actuation for holding the actuator position. Both series- and shunt-type switches have been implemented using the proposed actuation mechanism. From the fabricated switches, feasibility of operation has been successfully demonstrated. The fabricated switches can be operated within several hundred microseconds. In the series-type switch, the isolation has been measured as -34dB and insertion loss as -0.37dB at 20 GHz. In the shunt type switch, the isolation is -20.7dB and insertion loss is -0.85dB at 19.5 GHz. The proposed RF MEMS switches are mechanically robust and the combination of electromagnetic and electrostatic actuations makes it possible to achieve excellent switching characteristics at low power and low voltage below 5 V.

In situ compatibilized melt blends of polyamide 6 (PA-6) with polyester elastomer (PEL) were prepared in a corotating twin-screw extruder using two types of coupling agent (CA): diglycidyl ether of bisphenol A (DGEBA) and 1,4-phenylene bis(2-oxazoline) (PBO). The notched impact strength of PA-6 and PA-6/PEL blends increased with the addition of coupling agent, especially DGEBA, and the maximum impact toughening of the blend was obtained with 0.6 mol % DGEBA, the composition of minimum domain size observed from SEM. Viscosities of the untreated blends increased over those of the base resins at low frequencies. Viscosities of both the base resins and the blends increased with the addition of CA, and the effect was much more pronounced with DGEBA, especially for PA-6 and PA-6–rich blends. The crystallization temperature (Tc) of PEL increased over 10°C, whereas the Tc of PA-6 decreased by 2–3°C in the blends. With the addition of coupling agents, the crystallization melting temperature (Tm) and Tc of PA-6 decreased by up to 5°C with DGEBA, implying that the crystallization of PA-6 is disturbed by the in situ formed PA-6–CA–PEL or PA-6–CA–PA-6 type copolymer. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91: 3966–3973, 2004

A fully integrated CMOS power amplifier for 5 GHz WLAN applications is implemented using 0.18 μm CMOS technology. An on-chip transmission-line transformer is used for output matching and voltage combining. An input balun, interstage matching components, an output transmission-line transformer, and RF chokes are fully integrated in the amplifier, and thus no external components are required. The power amplifier occupies a total area of 1.7 mm × 1.2 mm. At a 3.3 V supply voltage, the amplifier exhibits a 22.6 dBm output 1 dB compression point, 23.8 dBm saturated output power, and 25 dB power gain. The power added efficiency (PAE) is 21% at maximum, 19% at P1dB. When a 54 Mbps/64 QAM OFDM signal is applied, the PA delivers an average power of 12 dBm at an EVM of −25 dB. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2551–2553, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24683

Polyurethane (PU) ionomers and non-ionomers with various soft segment contents (SSC) and lengths have been synthesized from polycaprolactone diols (PCL), 4,4′-diphenylmethane diisocyanate (MDI), 1,4-butanediol (BD) and dimethylolpropionic acid (DMPA), and tested for shape memory behaviour as well as for mechanical and dynamic mechanical properties. It was found that ionomers gave higher hardness, modulus and strength as compared with non-ionomers, and the effects were more pronounced with increasing hard segment contents (HSC) and at room temperature, since the increased HSC makes use of more Coulombic forces which are stronger at room temperature than at high temperature. Regarding the tensile cyclic behaviour, ionomers gave higher recovery strain and lower residual strain, and these were interpreted in terms of dynamic mechanical properties, i.e. the higher the rubbery modulus, the higher the recovery strain results.

This paper describes a novel microchip filter device incorporating slit arrays and 3-dimensional flow that can separate rare cells with high efficiency and throughput. The proposed device has several tens of times increased throughput, and has a unique pressure distribution along the filter pore, inducing target cells to be captured and gently lined up at the end of the slit in relatively low shear stress condition. With the enhanced capture yield and throughput, the proposed device can be used as an efficient rare-cell-analyzing tool for blood-based diagnostics.

We present a novel method for separating circulating tumor cells (CTCs) with high recovery and purity at the same time using a micro-slit filter chip and a fully automated fluidic system. Considering white blood cells (WBCs) as big as CTCs are also captured with CTCs during filtration, we amplified the size of CTCs specifically using microbeads (3 μm) coated with anti-Epithelial Cell Adhesion Molecule (anti-EpCAM) to increase the size difference between WBCs and CTCs. The average diameter of MCF-7 cells was increased from 16.5 μm to 23.1 μm. A micro filter chip having an extremely high aspect ratio (AR=3488) rectangular slit was designed to prevent clogging which induces unwanted aggregation, capturing of other small blood cells and consequently decreasing purity. A fully automated fluid control system was implemented for the better reproducibility and the minimization of handling errors. The procedures from blood loading to staining, prior to analysis, were performed automatically. With the optimized condition, separation experiments using 5ml of normal whole blood spiked with 100 MCF-7 cells have demonstrated the reduction of clogging, high recovery (91.1 %) and high purity (52.0 %) at the same time.

Parenchymal pulmonary endometriosis is the likely cause in patients with hemoptysis, dyspnea, or chest pain during menstruation. Embolization of endometrial tissue from the uterus to the lungs via the pulmonary arteries has been proposed for the mechanism of the development of parenchymal pulmonary endometriosis. This is a report of a woman with catamenial hemoptysis which was responded successfully to danazol therapy; however, hemoptysis resumed after cessation of therapy. The patient was subsequently treated with danazol again because she refused surgical treatments.

A X-band CMOS power amplifier (PA) has been fabricated using a 0.18-mum CMOS technology. On-chip transmission line transformers are used as matching elements for output, input, and inter-stage matching. The power amplifier provides the saturated output power of 23.5 dBm and 1-dB gain-compressed output power (P1dB) is 21 dBm at 8.5 GHz with 3.3 V supply. The gain is 29 dB and power-added-efficiency (PAE) is 19 % at 8.5 GHz. Among the reported X/Ku band CMOS power amplifiers, this amplifier has the largest output power.

A 1.8 GHz power amplifier for a polar transmitter application is implemented with 0.18 mum RF CMOS technology, and a differential line inductor is proposed for the differential circuit. The differential line inductor is used as a low power matching network in the stage-convertible power amplifier in order to increase the efficiency of a low output power region. The power amplifier achieved a power-added efficiency of 41% at a maximum output power of 31.5 dBm. The low power efficiency improvement for the power amplifier is 81% at an output power of 20 dBm.

In this paper we report a 2.4 GHz low-power receiver front-end using current-reused folded-cascode scheme. Two fully integrated receiver front-ends are presented as a proof of concept. A conventional merged LNA and single-balanced (SB) mixer shows a conversion gain of 20.4 dB and a noise figure of 19 dB at 10 MHz intermediate frequency (IF), taking 500 /spl mu/A bias current from 1.0 V power supply. The proposed front-end achieves a conversion gain of 30.5 dB and a noise figure of 10.2 dB at 10MHz IF with the same power consumption of 500 /spl mu/W. The front-ends performances are compared with the previously reported low-power front-ends operating at similar frequency.

In most short-range wireless sensor network applications, the maximum transmit-power is typically about 10 dBm at 2.4 GHz ISM band. In such a low transmit-power level, the driving power and DC power consumption in the previous stage are no more negligible compared to the transmitted signal power. So, to increase the overall transmitter efficiency, not only the output power stage, but also the driver stage needs to be co-optimized for low power operation. In this paper, we present an injection-locked Class-E power amplifier (Class-E ILPA) suitable for the low transmit-power sensor network applications. The proposed power amplifier, which is fully integrated in 0.18 /spl mu/m CMOS technology, achieves a power added efficiency (PAE) of 43% while delivering an output power of 9.5 dBm with a drain efficiency (DE) of 48.5% at 1 V supply voltage.

Hypertriglyceridemia (HTG) is a rare but well known cause of acute pancreatitis (AP), which can be a life- threatening complication if the degree of HTG is severe enough. It might be primary in origin or secondary to alcohol abuse, diabetes mellitus, pregnancy, or drugs. A serum triglyceride (TG) level of more than 1,000 to 2,000 mg/dL in patients with type I, IV, or V hyperlipidemia (Fredrickson's classification) is the identifiable risk factor. HTG-induced AP typically presents as an episode of AP or recurrent AP. The clinical course of HTG-induced AP is not different from other causes. Routine management of HTG-induced AP should be similar to other causes. A thorough family history of lipid abnormalities should be obtained, and an attempt to identify secondary causes should be made. The mainstay of treatment includes dietary restriction of fatty meal and lipid-lowering medications (mainly fibric acid derivatives). Although there are limited experiences with plasmapheresis, lipid apheresis, heparinization and insulin application, these can support the treatment of HTG- induced AP. We report two cases of HTG-induced AP which were successfully treated by plasmapheresis.

In this paper, we have proposed and fabricated a new shunt-type RF MEMS switch actuated by a combination of Lorentz force and electrostatic hold for low power consumption and low voltage operation. There is no static power consumption because it only consumes power when changing state. The proposed switch can be operated with large actuation force and it can enhance power handling capability and mechanical stability. The fabricated switch is actuated with an applied current of 49 mA and the actuation voltage is 3.3 V. Also, the power consumption is 87.9 /spl mu/J per switching.

In this paper, we have proposed and fabricated a new push-pull type SPDT switch implemented in a single structure with torsion bars actuated by the combination of electromagnetic and electrostatic forces for low power and low voltage operation. The proposed switch is actuated by using large electromagnetic force at low voltage to change its state and is held to maintain its state by electrostatic force to reduce static power consumption. From the prototype, actuation voltage is measured as 4.3V and required energy is below 15.4/spl mu/J per each switching. Also, we have successfully carried out a lifetime test over more than 166 million cycles without significant degradation of switch characteristics.

For the first time, low noise distributed oscillators for millimeter wave signal generation have been realized by using fully IC compatible, monolithically-integrable 3-D RF MEMS transmission lines. The active core circuits of the distributed oscillators have been fabricated using 0.18 /spl mu/m CMOS processes. On the top of this CMOS circuits, low-loss MEMS transmission lines have been monolithically integrated suspending by 25 /spl mu/m. Phase noise of the fabricated MEMS distributed oscillators has been measured as -125.7 dBc/Hz at 1 MHz offset frequency from oscillation frequency of 13 GHz. This is the lowest phase noise ever reported on distributed oscillators implemented in CMOS technology.

In this paper, we report the performance comparison of 5 GHz CMOS VCOs fabricated by 0.18 /spl mu/m six-metal mixed-mode RF CMOS processes with respect to the same VCOs integrated with high Q MEMS inductors. The CMOS inductors implemented by a top-level 2 /spl mu/m-thick Al/Cu metal layer typically show Q factors of about 10, while the MEMS inductors can give much higher Q factors over 25. Differential CMOS VCO circuits have been optimally designed for the respective Q factors of both CMOS and MEMS inductors. Phase noise has been measured and compared for the fabricated VCOs, demonstrating that the VCOs with MEMS inductors can give better phase noise by more than 7 dB in the offset frequency range from 30 kHz to 3 MHz.

Optical tweezers were used for quantitative measurement of the absolute dielectrophoresis (DEP) forces acting on polystyrene microparticles. The electrodes and tweezers were configured to create one-dimensional DEP forces acting perpendicular to the tweezers' beam. The influences of various external factors, such as applied voltage frequency, conductivity of the medium, and particle size on the measurement were estimated. By accounting for these factors, actual measurements were in close agreement with theoretical predictions. Our results show that the optical tweezers may serve as a unique tool for the measurement of DEP forces in various applications.