• Title/Summary/Keyword: band

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A design of single side-band filter for millimeter wave using martin-puplett interferometer (Martin-puplett 간섭계를 이용한 밀리미터파 대역의 단측파대 여파기 설계)

  • 한석태;김효령;이창훈;박종애;정현수;김광동;김태성;박동철
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.33A no.4
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    • pp.98-105
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    • 1996
  • The design method of 85 GHz-115 GHz band single side-band filter using the principle of martin-puplett inteferometer is described. It has been designed by this method and also manufactured and tested. From the test results, not only the ratio of image singal rejection of 19 dB is obtained, but also the theoretical and experimental results of center frequency of pass-band and rejection-band show the validity of the theory. This manufactured filter was installed on 100GHz band SiS (superconductor insulator superconductor ) receiver for observing cosmic radio waves and tested. We found that this filter can be used a single side-band as well as double side-band mode. The design method which is presented in this paper can be used a single side-band filter for a heterodyne type sub-milimeter wave receiver.

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Compact Dual-Band Bandpass Filter Using U-Shaped Stepped-Impedance Resonators with Parallel Coupled Structures

  • Sung, Gyuje
    • Journal of electromagnetic engineering and science
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    • v.18 no.2
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    • pp.73-77
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    • 2018
  • This paper proposes a dual-band bandpass filter using stepped-impedance resonators (SIRs) with parallel coupled structures. The proposed filter adopts U-shaped SIRs with parallel coupled lines (PCLs) that have interdigital and comb-line shorted ends. The central PCLs build an upper passband and a transmission zero, and the two U-shaped SIRs build a lower passband. Four resonators and coupling structures are theoretically analyzed to derive its scattering parameters. A novel dual-band bandpass filter is designed and fabricated using the induced scattering characteristics. The measured results show that the fabricated dual-band bandpass filter has an insertion loss of less than 1.02 dB in the lower band of 2.45 GHz and of 3.01 dB in the upper band of 3.42 GHz, and a band-to-band isolation of more than 40 dB, from 3.14 to 3.2 GHz.

Dual-Band MIMO Antenna Using a Band Stop Matching Circuit for USB Dongle Applications (대역 저지 특성을 갖는 정합 회로를 이용한 USB Dongle용 이중 대역 MIMO 안테나)

  • Han, Min-Seok;Choi, Jae-Hoon
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.20 no.9
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    • pp.924-929
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    • 2009
  • In this paper, a dual-band MIMO antenna with a band stop matching circuit for next generation USB dongle application is proposed. The proposed multiband MIMO antenna consists of two dual-band PIFAs which provide wideband characteristics. In order to improve the isolation characteristic at the LTE(Long Term Evolution) band, a band stop matching circuit was inserted at the corner of each antenna element. The inserted band stop matching circuit is to suppress the surface current at the specific frequency band and to generate two additional resonances around 770 MHz for LTE band and near 830 MHz for digital communications network(DCN) service. The proposed MIMO antenna can cover LTE and DCN services, simultaneously.

Design of Dual-Band Bandpass Filters for Cognitive Radio Application of TVWS Band

  • Kwon, Kun-An;Kim, Hyun-Keun;Yun, Sang-Won
    • Journal of electromagnetic engineering and science
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    • v.16 no.1
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    • pp.19-23
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    • 2016
  • This paper presents a novel design for dual-band bandpass filters. The proposed filters are applicable to the carrier aggregation of the TV white space (TVWS) band and long-term evolution (LTE) band for cognitive radio applications. The lower passband is the TVWS band (470-698 MHz) whose fractional bandwidth is 40 %, while the higher passband is the LTE band (824-894 MHz) with 8 % fractional bandwidth. Since the two passbands are located very close to each other, a transmission zero is inserted to enhance the rejection level between the two passbands. The TVWS band filter is designed using magnetic coupling to obtain a wide bandwidth, and the LTE band filter is designed using dielectric resonators to achieve good insertion loss characteristics. In addition, in the proposed design, a transmission zero is placed with cross-coupling. The proposed dual-band bandpass filter is designed as a two-port filter (one input/one output) as well as a three-port filter (one common input/two outputs). The measured performances show good agreement with the simulated performances.

Comparison the Variability of Multi-channel Soil Moisture Data Using PSR C-band and ESTAR L-band Estimates (PSR C-band 및 ESTAR L-band 측정치를 사용한 다중 채널 원격측정 토양수분 자료의 변화도 비교)

  • Kim, Gwangseob
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.4B
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    • pp.329-334
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    • 2006
  • The spatial variability of the L- and C- band large scale remotely sensed soil moisture data, obtained during the Southern Great Plain 1999 Experiment (SGP'99), was characterized. The results demonstrate that soil moisture data using L-band show the break in statistical symmetry (multiscaling behavior) with the variation of scale of observation, which is similar to that of the soil property such as sand content. Also, soil moisture data using C-band show single scaling behavior with the variation of scale of observation, which is similar to that of the vegetation condition. The results should be considered during downscaling the Global soil moisture data using AMSR instrument.

A Design of CPW Band-Pass Filter with Rejection Band for Ultra-Wideband System (저지 대역을 갖는 UWB용 CPW 대역 통과 여파기의 설계)

  • No, Jin-Won;Hwang, Hee-Yong
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.18 no.7
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    • pp.704-709
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    • 2007
  • In this paper, a CPW band-pass filter with a rejection band is proposed for UWB(Ultra-Wideband) communication systems. The proposed filter has a band-pass characteristic of wide-band by inserting only a slot in $50{\Omega}$ transmission line. To obtain the band-rejection function at WLAN frequency band($5.15{\sim}5.725GHz$), the designed filter is combined with folded slot resonators on the ground plane of the CPW structure. The fabricated CPW band-pass filter shows a compact size of $15.35{\times}13.60mm$, a wide passband of 2.8 GHz to 9.8 GHz and the narrow stop-band of 5.15 GHz to 5.71 GHz for 3-dB bandwidth. Also, the measured group delay is less than 400 psec throughout the operation frequency band except the rejection band.

Estimation and Weighting of Sub-band Reliability for Multi-band Speech Recognition (다중대역 음성인식을 위한 부대역 신뢰도의 추정 및 가중)

  • 조훈영;지상문;오영환
    • The Journal of the Acoustical Society of Korea
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    • v.21 no.6
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    • pp.552-558
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    • 2002
  • Recently, based on the human speech recognition (HSR) model of Fletcher, the multi-band speech recognition has been intensively studied by many researchers. As a new automatic speech recognition (ASR) technique, the multi-band speech recognition splits the frequency domain into several sub-bands and recognizes each sub-band independently. The likelihood scores of sub-bands are weighted according to reliabilities of sub-bands and re-combined to make a final decision. This approach is known to be robust under noisy environments. When the noise is stationary a sub-band SNR can be estimated using the noise information in non-speech interval. However, if the noise is non-stationary it is not feasible to obtain the sub-band SNR. This paper proposes the inverse sub-band distance (ISD) weighting, where a distance of each sub-band is calculated by a stochastic matching of input feature vectors and hidden Markov models. The inverse distance is used as a sub-band weight. Experiments on 1500∼1800㎐ band-limited white noise and classical guitar sound revealed that the proposed method could represent the sub-band reliability effectively and improve the performance under both stationary and non-stationary band-limited noise environments.

Electrophoretic Variations in Protein and Some Enzymes during Stratification of Panax ginseng Seeds (인삼종자의 개갑처리과정에 있어서 단백질 및 몇가지 효소의 전기영동특성변이)

  • 최선영
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.35 no.4
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    • pp.334-341
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    • 1990
  • The electrophoretic variations in protein and some enzymes during stratification of Panax ginsseng seeds were checked in relation to the differentiation and development of immature embryo, Seed-protein on PAGE showed eight major bands during the period of investigation, Four bands of Rf : 0.12, 0.24, 0.66 and 0,72 remained in dark stained condition, whereas the remainders (Rf : 0.40, 0.48, 0.56 and 0,76) became lighter in the staining condition as the treatment period was prolonged, In embryo, which was separately sampled from 75 days after the treatement, the only band of Rf 0.76 was not observed, In peroxidase, the number of bands was gradually increased and came to four bands at 45 days after treatment, and their staining color became gradually darker until the time of final samling. Also, the embryo had the same patterns as those in the intact seed. Esterase showed four bands during the period of investigation. As the treatment period was prolonged, the degree of staining condition came to darker in the band of Rf 0.36, but lighter in the band of Rf 0.56. The band of Rf 0.20 was not detected in the intact seed at 90 days after the treatment, but clearly observed in embryo. Glutamate dehydrogenase had only two bands: one (Rf : 0.16) was detected only at 60 days after the treatment and the other (Rf: 0.14) was always observed throughout the period, and showing simple pattern in the electrophoretic variation. Glutamate-oxaloacetate transaminase showed the only band of Rf 0.36 during the period of investigation and even in embryo, and showing the simplest pattern, indeed.

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Purification of Band 3 from the Human Erythrocyte Membrane and its Incorporation into Liposome (사람 적혈구막 Band 3의 정제 및 Liposome으로의 도입)

  • Kim, Jae-Ryong;Kim, Jung-Hye;Lee, Ki-Yung
    • Journal of Yeungnam Medical Science
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    • v.3 no.1
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    • pp.41-48
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    • 1986
  • Band 3, the predominent 95,000 dalton anion transport protein, is the major intrinsic glycoprotein of the human erythrocyte membrane. This anion carrier exists as a dimer and binds the cytoskeletons such as spectrin, ankyrin and actin. And the liposomes are vesicular structures which form spontaneouly upon hydration of phospholipids. These artificial lipid vesicles have been investigated as model of the biological membranes and as a mean of improving the delivery of nucleic acids, drugs, proteins and biological substances to specific target tissues and cells. In this study, we were purified Band 3 from the human erythrocyte membrane(ghost) was prepared by hemolysis of intact human erythrocyte with weak alkali-hypotonic solution. Band 6 was removed from ghost by extracting with solution of an ionic strength of 0.15. Band 3 and Band 4 were solubilized selectively by extracting Band 6-depleted ghosts with Triton X-100 under nondenaturing conditions. Band 3 was then purified from Triton X-100 extract treated with p-chloromercuribenzoate by sucrose density gradient ultracentrifugation. This purified Band 3 was incorporated into liposomes prepared by reverse-phase evaporation. Phosphatidyl L-serine and cholesterol(1 : 1 molar ratio) were dissolved in chloroform and then chloroform was removed by rotatory evaporation under reduced pressure. Band 3 solution without Triton X-100 was introduced into a mixture of lipids and diethylether. Diethylether was subsequently removed by evaporation. This purified Band 3 and its incorporation into liposomes were confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis.

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Changes of Nitrogen Compounds and Nutritional Evaluation of Soybean Sprout -Part VI. Changes in electrophoretic pattern of protein- (콩나물 제조중(製造中) 질소화합물(窒素化合物)의 변화(變化)와 그 영양학적(營養學的) 연구(硏究) -제육보(第六報). 단백질(蛋白質)의 전기영동양상변화(電氣泳動樣相變化)-)

  • Yang, Cha-Bum;Park, Sang-Ki;Yoon, Suk-Kwon;Park, Hoon
    • Applied Biological Chemistry
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    • v.27 no.2
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    • pp.129-134
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    • 1984
  • Change of protein component in soybean sprout grown at four temperatures was investigated by polyacrylamide gel electrophoresis. Main bands were identified using purified seed globulins. Electrophoretogram showed 5 main bands (a. b, c, d, and p) and 10 minor bands in seed and maximum number (19) of bands (8 main band including 0 and 11 minor) at 4th day after germination in cotyledon. All bands appeared in axis protein but resolution was poor. In cotyledon, a component (most rapidly) and b+c+d component decreased while o+p component and other minor components were increased at 6th day and decreased thereafter. In axis all components increased rapidly, especially in minor components and b+c+d component. High growing temperature accelerated decrease in cotyledon and increase in axis of protein, especially for 11S. The a component was identified as 7S, b+c+d as 11S and o+p as 2S globulin.

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