• Title/Summary/Keyword: U-band

Search Result 531, Processing Time 0.025 seconds

Cell Biological Characteristics of Trimorphomyces papilionaceus diploid (담자성 효모 Trimorphomyces papilionaceus 이배체균의 세포학적 특성)

  • 정해숙;최형태;윤권상
    • Korean Journal of Microbiology
    • /
    • v.31 no.1
    • /
    • pp.22-26
    • /
    • 1993
  • Trimorphomyces papilionaceus dikaryon 으로부터 자영적인 돌연변이에 의해 분리한 이배체를 대상으로 생장속도, U. V. 광 조사 후의 생존율, U. V. 분광광도계와 Hoechst 33258 핵염색에 의한 DNA 함량등을 monokaryon 및 dikaryon 과 비교하여 결정하였다. 이배체는 dikaryon 핵의 DNA 양과 비슷하였고 monokaryon 핵의 DNA 양의 2배 정도가 되었다. Glyoxalase II 의 band 양상에서 monokayon은 한 개의 isozyme band 만을 보인 반면, 이배체와 dikaryon은 같은 위치에서 두개의 isozyme band 가 관찰되었다. 이원전개한 전기영동실험에서 dikaryon 특이 단백질은 분자량이 66.000 보다 컸으며 분자량 24,000-29,000 사이에서 이배체 특이 단백질이 존재한다.

  • PDF

Design of Wide Band U-slot Patch Antennas for Mobile Communications (이동통신용 광대역 U-슬롯 패치 안테나 설계)

  • 전주성
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.12 no.6
    • /
    • pp.882-889
    • /
    • 2001
  • In this paper, the characteristics of u-slot antennas are computed by changing the feed structure, and compared with the measured results. The impedance bandwidths of 13 %(255.1 MHz) and 30.7 %(602.1 MHz) are obtained for probe feed and L-strip feed, respectively. It is known that the designed L-strip feed can be used for increasing the bandwidth of u-slot antennas. In addition, it is shown that the designed L-strip feed u-slot antenna can be used for domestic PCS and IMT-2000 dual band applications.

  • PDF

A Study on an Optimal Design of a Triple-band PIFA using the Evolution Strategy (진화 알고리즘을 이용한 삼중대역 PIFA 최적 설계에 관한 연구)

  • Ko, Jae-Hyeong;Kim, Koon-Tae;Kim, Kyong-Ah;Kim, Hyeong-Seok
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.59 no.4
    • /
    • pp.768-773
    • /
    • 2010
  • In this paper, we study on an optimal design of a triple-band PIFA (Planar Inverted-F Antenna) of 433 MHz, 912 MHz and 2.45 GHz by using evolution strategy. Generally, the resonant frequency of the PIFA is determined by the width and length of a U-type slot used. However the resonant frequencies of the multiple U slots are varied by the mutual effect of the slots. Thus the optimal width and length of U-type slots are determined by using an optimal design program based on the evolution strategy. To achieve this, an interface program between a commercial EM analysis tool and the optimal design program is constructed for implementing the evolution strategy technique that seeks a global optimum of the objective function through the iterative design process consisting of variation and reproduction. The resonant frequencies of initial model are 439.5 MHz, 981.5 MHz and 2.563 GHz. However, the resonant frequencies of the triple-band PIFA yielded by the optimal design program are 430.5 MHz, 907 MHz and 2.4515 GHz. Measured resonant frequencies are 433.5 MHz, 905.5 MHz and 2.454GHz, which show a good agreement with the simulation results.

Design of a Pot-Shaped Monopole Antenna with Dual Band Notched Characteristics for UWB Application

  • Mok, Kwang Yun;Rhee, Young Chul;Yoon, Joong Han
    • Journal of electromagnetic engineering and science
    • /
    • v.17 no.1
    • /
    • pp.44-49
    • /
    • 2017
  • A compact planar microstrip-fed ultra-wideband (UWB) antenna with a dual band-notched for UWB application is presented and analyzed. By inserting a U-shaped slot and inverted U-shaped slot into the pot-shaped radiator, two notched bands are achieved. By optimizing the width and length of the U-shaped slots and inverted U-shaped slot, a desired bandwidth of voltage standing wave ratio (VSWR) less than 2.0 can be achieved, ranging from UWB bands with notched dual bands. The proposed antenna is fabricated on an inexpensive FR-4 substrate with overall dimensions of $28.0mm{\times}39.5mm$. The measured results confirm that the proposed antenna covers from 1.775 to over 13.075 GHz with two rejection bands of around 3.325-3.925 GHz and 5.3125-6.025 GHz. In addition, the proposed antenna showed good radiation characteristics and gains in the UWB bands.

A study of U-slot Microstrip Antenna (U-slot 마이크로 스트립 안테나 연구)

  • Park, Yong-Wook
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.13 no.8
    • /
    • pp.3623-3627
    • /
    • 2012
  • The modern society has become full-fledged entry into the information age since spread of Internet. In the information age, internet was developed from the wired access to the wireless Internet access. When a surge in demand for wireless Internet access, efficiency and performance of 2.4GHz band which leads to saturation of the communication was significantly fall. Accordingly, the communication of the 5GHz band came to be interested. In this paper, we studied the design and fabrication of u-slot microstrip patch antenna to be used in wireless communication systems operating at around 5GHz band. To obtain antenna parameters such as patch size, inter patch space, antenna was simulated by HFSS(High Frequency Structure Simulator). From these parameters, u-slot microstrip patch antenna is fabricated using FR-4 substrate of dielectric constant 4.4. The characteristics of fabricated antenna were analyzed by network analyzer.

Unlicensed Band Traffic and Fairness Maximization Approach Based on Rate-Splitting Multiple Access (전송률 분할 다중 접속 기술을 활용한 비면허 대역의 트래픽과 공정성 최대화 기법)

  • Jeon Zang Woo;Kim Sung Wook
    • KIPS Transactions on Computer and Communication Systems
    • /
    • v.12 no.10
    • /
    • pp.299-308
    • /
    • 2023
  • As the spectrum shortage problem has accelerated by the emergence of various services, New Radio-Unlicensed (NR-U) has appeared, allowing users who communicated in licensed bands to communicate in unlicensed bands. However, NR-U network users reduce the performance of Wi-Fi network users who communicate in the same unlicensed band. In this paper, we aim to simultaneously maximize the fairness and throughput of the unlicensed band, where the NR-U network users and the WiFi network users coexist. First, we propose an optimal power allocation scheme based on Monte Carlo Policy Gradient of reinforcement learning to maximize the sum of rates of NR-U networks utilizing rate-splitting multiple access in unlicensed bands. Then, we propose a channel occupancy time division algorithm based on sequential Raiffa bargaining solution of game theory that can simultaneously maximize system throughput and fairness for the coexistence of NR-U and WiFi networks in the same unlicensed band. Simulation results show that the rate splitting multiple access shows better performance than the conventional multiple access technology by comparing the sum-rate when the result value is finally converged under the same transmission power. In addition, we compare the data transfer amount and fairness of NR-U network users, WiFi network users, and total system, and prove that the channel occupancy time division algorithm based on sequential Raiffa bargaining solution of this paper satisfies throughput and fairness at the same time than other algorithms.

The Design of U-Slot Stack Structure Antenna for 800MHz Band Coastal Sea Base Station Applications (800MHz 대역 연안해역기지국용 U-Slot 적층구조 안테나 설계)

  • Kim, Kab-Ki
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.12 no.6
    • /
    • pp.984-989
    • /
    • 2008
  • In this paper, we will design a 800MHz broadband antenna after a problem of the narrow bandwidth is improved. This multiple band antenna unifies the CDMA(Code Division Multiple Access), GSM(Global System for Mobile Telecommunication) and TRS(Trunked Radio System) band in the UHF band, and then it is possible at the shore base station or repeater as the commercial use. It used the duplex resonance effect it had the L-shared feeding structure which adds the U-slot. And it improved profit using stack structure. It was measured that the frequency bandwidth of the designed antenna which is planed $792{\sim}1040MHz$ with 248MHz(33%). And the antenna gain is 9.4dBi, 3dB beam width $60^{\circ}$ in radiation pattern.

Analysis and Design of Nth-band FIR Filters with Equi-Ripple Passband Response (Nth 밴드 FIR 필터의 균일 리플 통과 대역 응답을 위한 해석과 설계)

  • Moon, Dong-Wook;Kim, Lark-Kyo
    • The Transactions of the Korean Institute of Electrical Engineers D
    • /
    • v.54 no.10
    • /
    • pp.630-638
    • /
    • 2005
  • In FIR (Finite Impulse Response) filter applications, Nth-band F]U digital filters are known to be important due to their reduced computational requirements. The conventional methods for designing F]U filters use iterative approaches such as the well-known Parks-Mcclellan algorithm. The Parks-Mcclellan algorithm is also used to design Nth-band FIR digital filters. But a disadvantage of the Parks-Mcclellan algorithm is that it needs a good amount of design time. This paper describes a direct design method for Nth-band FIR Filters using Chebyshev polynomials, which provides a reduced design time over indirect methods such as the Parks-Mcclellan algorithm. The response of the resulting filter is equiripple in passband. Our proposed method produces a passband response that is equripple to within a minuscule error, comparable to that of the Parks-Mcclellan algorithm.

Design and Fabrication of Mulitiple U-shaped slot Microstrip Antenna on 5㎓ Application (5㎓ 대역에서 동작하는 다중 U-슬롯 모양의 마이크로스트립 안테나의 설계 및 제작)

  • 윤중한;정계택;이상목;안규철;곽경섭
    • Journal of the Institute of Electronics Engineers of Korea TC
    • /
    • v.40 no.11
    • /
    • pp.85-92
    • /
    • 2003
  • In this paper, a multiple U-shaped slot antenna on 5㎓ band is designed, fabricated, and measured. The prototype consists of a U-shaped slot and two Invert U-shaped slot. To obtain wide bandwidth, the foam layer is inserted between ground plane and substrate. After various parameters, length, width, position of U-shaped slot horizontal, interval length between two invert U-shaped slot, feeding position and airgap width, optimized, a multiple U-shaped slot antenna is fabricated and measured. The measured results of the antenna are compared with its simulated results. A 2:1 VSWR impedance bandwidth of 20.4% is achiedved by employing this technique. The gain is about 5.5㏈i. The experimental far-field patterns are stable across the pass band.

Design of Antenna for UWB Application notched WLAN-Band (무선랜 대역 저지특성을 갖는 UWB 안테나 설계)

  • Kim, Kab-Ki
    • Journal of Advanced Navigation Technology
    • /
    • v.13 no.5
    • /
    • pp.714-719
    • /
    • 2009
  • In this paper, a compact antenna with band-rejected characteristic for Ultra-Wideband(UWB) applications is proposed. The designed antenna not only shows sufficient impedance bandwidth but has band-rejected characteristic for the frequency band of 5.15~5.825GHz limited by IEEE 802.11a and HIPERLAN/2. To obtain both properties of wideband band rejection, the techniques of a partial ground plane and embedded thin U-slot into planar radiator are used respectively. A designed antenna satisfied a VSWR less than 2:1 for the frequency band of 3.1~10.3GHz with band rejection of 4.90~5.92GHz.

  • PDF