• Title/Summary/Keyword: triple-frequency

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The Benefit of Ambiguity Resolution Using Triple Frequency

  • Tominaga, Reiji;Gomi, Yasuto;Zhang, Yun;Kubo, Nobuaki;Yasuda, Akio
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.2
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    • pp.23-26
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    • 2006
  • Modernized GPS will have three frequencies modulated with three signals, which will be accessible to all users in the near future. This new frequency provides an opportunity to resolve the double differenced (DD) integer ambiguity very fast and with almost no baseline constraints. In order to study the performance of triple frequency system for Ambiguity Resolution (AR) over the medium baseline under different ionospheric levels, the Klobuchar Model was implemented and used in our triple simulation to generate the ionospheric delay. Furthermore, the White-Gaussian noise applying to distance-dependent parameters was added to the DD ionospheric delay. For medium baseline (defined as here 20 to 40kms), success rates of AR has been pretty improved. In this paper, the medium baseline AR strategies that take advantage of carrier phase measurement on the third frequency will be discussed.

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Applications of Triple Controlled Type DDFS-driven PLL Frequency Synthesizer to Broadband Wireless Systems (3중조절 DDFS 구동 PLL 주파수 합성기의 광대역 무선 통신시스템에 응용)

  • Heung-Gyoon Ryu;Byeong-Rok An
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.13 no.6
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    • pp.546-551
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    • 2002
  • In this paper, a triple controlled type DDFS-driven PLL frequency synthesizer with reduced complexity is used to show its applications for broadband wireless communication systems by frequency synthesis control. Since the proposed DDFS-driven PLL synthesizer is very simplified to use only phase accumulator in DDFS, it improves the switching speed and power consumption than the conventional DDFS-driven PLL frequency synthesizer. It is appropriate for applications with requirements of broadband, low-power consumption and high switching speed, since the proposed synthesizer can cover a wide range of frequency bands by the triple frequency control parameters. Method and results of frequency control parameters assignment are shown for the several frequency bands applications such as GSM, IMT-2000, Bluetooth and PCS system.

Design of Frequency-Tunable Microstrip Filter Using Triple-Mode Substrate Integrated Waveguide (SIW) Structure (3중모드 기판집적 도파관(SIW) 구조를 이용한 주파수 가변 마이크로스트립 필터 설계)

  • Kyeong-Min Na;Dong-Woo Kim;Soon-soo Oh
    • Journal of IKEEE
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    • v.28 no.1
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    • pp.72-77
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    • 2024
  • In this paper, a triple-mode frequency-tunable filter is proposed to meet the recent demands of various frequency bands of mobile communication services. This filter has a tunable structure that can adjust the resonance frequency using a variable capacitor. To improve the quality factor, a SIW(Substrate Integrated Waveguide) structure was introduced and a structure that induces three resonance modes was implemented through a circular hole located in the center. The change in electric field distribution and resonance frequency by the variable capacitor was simulated using HFSS, and the change in electric field distribution and resonance frequency of Triple Mode mode was confirmed.

Different Prognostic Factors Correlate with Bcl-2 Expression among Triple Negative and Non-Triple Negative Breast Cancers

  • El-Mageed, Amal Abd El-Hafez Abd;Shawky Mohamed, Abd El-Aty;Elesawy, Basem Hasan
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.2
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    • pp.1037-1041
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    • 2013
  • Background: Prognostication of breast cancer using clinico-pathologic variables, although useful, remains imperfect. Recent research has focused on finding new markers of prognosis using gene expression profiling. Panels of proteins assessed by immunohistochemistry might also be useful in this regard. This study focused on Bcl-2 protein expression in triple-negative (TNBC) and non- triple-negative breast cancer (non-TNBC) with correlation to clinico-pathologic variables. Materials and methods: We analyzed Bcl-2 expression in 77 women with primary breast carcinoma divided into two groups; triple-negative and non- triple-negative according to expression of estrogen (ER), progesterone (PR) and human epidermal growth factor receptors (Her2/neu). Bcl-2 expression was assessed in relation to age, histo-pathological subtype, grade, nodal status and tumor size. Results: Bcl-2 was expressed in 74% of triple-negative breast cancers and 70% of non- triple-negative cancers. In TNBC, expression was significantly correlated with invasive ductal subtype, while in non-TNBC it was significantly correlated with age and negative nodal status. In both groups higher Bcl-2 expression associated with favourable prognostic factors in breast cancer, but no significant statistical correlations were found. Conclusions: Frequency of Bcl-2 expression does not differ between TNBC and non-TNBC, but different prognostic factors correlate with Bcl-2 in the two cases.

Design of Triple-band Triple Dipole Quasi-Yagi Antenna for WLAN and WiMAX Applications (무선 랜과 WiMAX 응용을 위한 삼중 대역 삼중 다이폴 준-야기 안테나 설계)

  • Yeo, Junho;Lee, Jong-Ig
    • Journal of Advanced Navigation Technology
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    • v.26 no.1
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    • pp.29-34
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    • 2022
  • In this paper, the design of a triple dipole quasi-yagi antenna operating in the 2.45 GHz and 5 GHz wireless LAN frequency bands and the 3.5 GHz WiMAX frequency band was studied. The proposed quasi-Yagi antenna consists of three dipoles connected in series with a V-shaped ground plane. The longest half-bow-tie-shaped dipole resonates in the 2.45 GHz band, whereas the medium-length dipole resonates at 3.5 GHz. The shortest dipole resonates in the 5 GHz band. By adjusting the length and width of the dipoles and the spacings between the dipoles, a triple-band directional antenna operating in the 2.45 GHz, 3.5 GHz, and 5 GHz bands are designed, and fabricated on an FR4 substrate with a size of 45 mm × 55 mm. It was confirmed that the fabricated antenna operates in the designed triple bands of 2.32-2.57 GHz, 3.26-3.69 GHz, and 4.50-6.56 GHz for a voltage standing wave ratio less than 2. Gain is maintained above 3 dBi in the three bands.

Design of Ka/Ku Band Frequency Selective Surface with Triple Square Loop Slot Array (삼중 사각 루프 슬롯 배열 형태를 갖는 Ka/Ku 대역 주파수 선택 반사기 설계)

  • 고지환;조영기
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.14 no.10
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    • pp.1060-1070
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    • 2003
  • The frequency selective surface for use in Ka/Ku band parabolic antenna of domestic satellite communications is proposed. The frequency selective surface structure consists of the infinite periodic arrays of the triple square loop slot element with narrow width on the honeycomb structure of multi-layered dielectric. The frequency selective surface is fabricated and measured. The good agreement is obtained between theory and experiment. It is demonstrated that the frequency selective surface passes 14/12 GHz band wave while reflecting 30/20 GHz band wave as required.

The Optimal Design of a Triple-Band Antenna with Additional Arm Resonating Structure for LTE, ISM and WLAN Application (LTE, ISM, WLAN에 적용 가능한 Arm 구조 삼중대역 안테나 최적 설계)

  • Lee, Seung-Je;Oh, Seung-Hun;Lee, Jeong-Hyeok;Kim, Hyeong-Seok
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.63 no.12
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    • pp.1655-1660
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    • 2014
  • In this paper, we propose a design of a triple-band microstrip circular patch antenna. The proposed antenna generates the triple frequency resonance at 1.85GHz(LTE), 2.45GHz(ISM) and 5.5GHz(WLAN). Firstly, we design the dual-band antenna. The dual-band antenna consist of the circular patch, slits, and the slot. The circular patch and slot are designed for dual frequency of 2.45GHz and 5.5GHz, respectively. And then the dual-band antenna is combined with additional arm-shaped structure for the triple-band characteristic. The arm-shaped structure is operated as the dipole. It is designed for lowest frequency of 1.85GHz. Each part of the antenna unites to a new structure. In order to design the proposed antenna automatically and optimally, APSO algorithm is adopted. During APSO, the mismatch of the proposed antenna is resolved. The optimal designed antenna has an acceptable return loss(-10dB) at each bands(i.e, 1.85GHz, 2.45GHz and 5.5GHz).

An Enhanced Skirt Characteristics Triple-Mode Filter

  • Lee, Ja-Hyeon;Nam, Hun;Lim, Yeong-Seog
    • Journal of electromagnetic engineering and science
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    • v.12 no.3
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    • pp.210-215
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    • 2012
  • This paper presents a compact microstrip triple-mode filter with enhanced skirt characteristics. The presented triple-mode filter configuration supports three transmission poles and three transmission zeros within the nearby passband. Two of transmission zeros are generated by a triple-mode resonator itself, and the third one is generated by small cross-couplings between the I/O ports. Each resonance condition and the transmission zero generation conditions are analyzed using an equivalent circuit. The bandpass filter is designed for a 2.4 GHz WLAN. The filter was fabricated with a relative dielectic constant of 3.5 and a thickness of 0.76 mm. The fabricated filter has a small size ($7.9mm{\times}7.2mm$, i.e., $0.107{\lambda}_g{\times}0.098{\lambda}_g$, where ${\lambda}_g$ is guided wavelength at a center frequency) and shows high performing skirt characteristics.

A High-Efficiency, Robust Temperature/voltage Variation, Triple-mode DC-DC Converter (고효율, Temperature/voltage 변화에 둔감한 Triple-mode CMOS DC-DC Converter)

  • Lim, Ji-Hoon;Ha, Jong-Chan;Kim, Sang-Kook;Wee, Jae-Kyung
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.45 no.6
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    • pp.1-9
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    • 2008
  • This paper suggests the triple-mode CMOS DC-DC converter that has temperature/voltage variation compensation techniques. The proposed triple-mode CMOS DC-DC converter is used to generate constant or variable voltages of 0.6-2.2V within battery source range of 3.3-5.5V. Also, it supports triple modes, which include Pulse Width Modulator (PWM) mode, Pulse Frequency Modulator (PFM) mode and Low Drop-Out (LDO) mode. Moreover, it uses 1MHz low-power CMOS ring oscillator that will compensate malfunction of chip in temperature/voltage variation condition. The proposed triple-mode CMOS DC-DC converter, which generates output voltages of 0.6-2.2V with an input voltage sources of 3.3-5.5V, exhibits the maximum output ripple voltage of below 10mV at PWM mode, 15mV at PFM mode and 4mV at LDO mode. And the proposed converter has maximum efficiency of 93% at PWM mode. Even at $-25{\sim}80^{\circ}C$ temperature variations, it has kept the output voltage level within 0.8% at PWM/PFM/LDO modes. For the verification of proposed triple-mode CMOS DC-DC converter, the simulations are carried out with $0.35{\mu}m$ CMOS technology and chip test is carried out.

Triple-Mode Characteristics of Cylindrical Cavity Loading a Cylindrical Dielectric Resonator

  • Lee, Seung-Mo;Kim, Cha-Man;Park, Jong-Chul;Kim, In-Ryeol;Oh, Soon-Soo
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.9 no.6
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    • pp.630-636
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    • 2016
  • In this paper, a novel triple-mode cavity structure, designed for compactness and operating at 850 MHz, is analyzed. A cylindrical dielectric resonator is loaded into a metallic cylindrical cavity. Previous study has been focused on the analysis of the cylindrical dielectric resonator, but in this paper, the effect of the cylindrical metallic cavity has been analyzed. Enclosing the dielectric resonator inside the metallic cavity increases the resonant frequency of the dielectric resonator; however, this increases the quality factor and introduces the possibility of installing coupling screws. The principle of generation of triple-mode was investigated by parametric analysis. The generated triple-mode is TE011 mode and two orthogonally generated HEM121 modes. By adjusting the radius of the dielectric resonator, the height of the dielectric resonator, or the radius of the cylindrical metallic cavity, three modes could be coincided. However, the height of the metallic cavity keeps three modes separated. The mode characteristics of the proposed cavity are analyzed using a full-wave electromagnetic (EM) simulation. The proposed triple-mode cavity could be developed to triple-mode filter using a coupling screw, and the commercial application for the miniaturized filter below 1 GHz could be expected.