• Title/Summary/Keyword: Shifter

Search Result 389, Processing Time 0.026 seconds

Low-Complexity and High-Speed Multi-Size Circular Shifter With Benes Network Control Signal Optimization for WiMAX QC-LDPC Decoder (Benes 네트워크 제어 신호 최적화를 이용한 WiMAX QC-LDPC 복호기용 저면적/고속 Multi-Size Circular Shifter)

  • Kang, Hyeong-Ju
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.19 no.10
    • /
    • pp.2367-2372
    • /
    • 2015
  • One of various low-density parity-check(LDPC) codes that has been adopted in many communication standards due to its error correction ability is a quasi-cyclic LDPC(QC-LDPC) code, which leads to comparable decoder complexity. One of the main blocks in the QC-LCDC code decoder is a multi-size circular shifter(MSCS) that can perform various size rotation. The MSCS can be implemented with many structures, one of which is based on Banes network. The Benes network structure can perform the normal MSCS operation efficiently, but it cannot use the properties coming from specifications like rotation sizes. This paper proposesd a scheme where the Benes network structure can use the rotation size property with the modification of the control signal generation. The proposed scheme is applied to the MSCS of IEEE 802.16e WiMAX QC-LDPC decoder to reduce the number of MUXes and the critical path delay.

Multi-Size Circular Shifter Based on Benes Network with High-Speed 3×3 Switch (고속 3×3 스위치를 이용한 Benes 네트워크 기반 Multi-Size Circular Shifter)

  • Kang, Hyeong-Ju
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.19 no.11
    • /
    • pp.2637-2642
    • /
    • 2015
  • The low-density parity check(LDPC) code is being widely used due to its outperformed error-correction ability. The decoder of the quasi-cyclic LDPC(QC-LDPC) codes, a kind of LDPC codes, requires a multi-size cyclic shifter(MSCS) performing rotation of various sizes. The MSCS can be implemented with a Benes network, which requires a $3{\times}3$ switch if the number of data to be rotated is a multiple of 3. This paper proposes a control signal generation with lower complexity and a faster $3{\times}3$ switch. For the experiment, the proposed schemes are applied to the MSCS of an IEEE 802.16e WiMAX QC-LDPC code decoder. The result shows that the delay is reduced by about 8.7%.

Development of phase shifter for Ka-band Passive Phase Array Seeker and Seeker Performance Analysis due to the Phase Error of Phase Shifter (Ka-대역 수동위상배열탐색기용 위상 변위기 개발 및 변위기 위상 오차에 의한 탐색기 성능 분석)

  • Kim, Youngwan;Woo, Seon-keol;Kwon, Jun-beom;Kang, Yeon-duk;Park, Jongkuk
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.19 no.3
    • /
    • pp.149-155
    • /
    • 2019
  • In this paper, phase shifter has been designed and manufactured to apply to passive phase array seeker for Ka-band and its performance was confirmed. It was designed as a key element for conducting electric beam steering by adjusting the phase of the array element. Insertion loss of less than 1.5dB and phase accuracy of less than $10^{\circ}$(RMS) in operation bandwidth of 1GHz were checked. The performance identified by the actual fabrication was further analyzed by applying the beam pattern analysis based on the array synthesis theory. The effect of the final performamnce of the proven phase shifter on the performance and pointing error and angular accuracy of the passive phase array antenna beam pattern was analyzed. Then, the validation of the proposed phase shifter has been made.

A Study on a New Broadband 180° Phase Shifter using the Network with Great Phase Dispersive Characteristics (강한 위상 산란 특성을 갖는 회로망을 이용한 새로운 광대역 180°위상 천이기에 대한 연구)

  • 엄순영
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.14 no.4
    • /
    • pp.401-412
    • /
    • 2003
  • In this paper, a broadband phase shifter structure using a new switched network was proposed. A new reference network is composed of coupled lines and 45$^{\circ}$open and short stubs, which are shunted at the edge points of a main line, respectively, A delay network is composed of only a standard transmission line. It is possible to design a broadband 180$^{\circ}$phase shifter that phase dispersive characteristics by an impedance ratio R of coupled lines and greater phase dispersive characteristics by characteristic impedances Zm, Zs of a main line and stubs are used together. By considering a structure symmetry, the even and odd mode analysis was performed to obtain theoretical S-parameters of the proposed phase shifter. Also, through computer simulation on the basis of derived equations, design graphs were presented to optimally design a 180$^{\circ}$broadband phase shifter. Design graphs provide the values of characteristic impedances Zm, Zs, and I/O match and phase bandwidths. To verify electrical performances of the broadband phase shifter proposed in this paper, low different 180$^{\circ}$phase shifters, operated at the center frequency 3 GHz were designed and fabricated using design graphs, and were experimented. One of them was designed as a standard Schiffman structure to compare with electrical performances. Measured results of each phase shifter to satisfy simultaneously design conditions of I/O match (VSWR=1.15:1) and maximum phase deviation $({\varepsilon}_{{\Delta}{\phi}}={\pm}2^{\circ})$ were well in agreement with corresponding simulation results over impedance match and phase error bandwidths, and showed broadband characteristics.

A 2 GHz Compact Analog Phase Shifter with a Linear Phase-Tune Characteristic (2 GHz 선형 위상 천이 특성을 갖는 소형 아날로그 위상천이기)

  • Oh, Hyun-Seok;Choi, Jae-Hong;Jeong, Hae-Chang;Heo, Yun-Seong;Yeom, Kyung-Whan
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.22 no.1
    • /
    • pp.114-124
    • /
    • 2011
  • In this paper, we present a 2 GHz compact analog phase shifter with linear phase-tune characteristic. The compact phase shifter was designed base on a lumped all pass network and implemented using a ceramic substrate fabricated with thin-film technique. For a linear phase-tune characteristic, a capacitance of the varactor diode for a tuning voltage was linearized by connecting series capacitor and subsequently produced an almost linear capacitance change. The inductor and bias circuit in the all pass network was implemented using a spiral inductors for small size, which results in the size reduction to $4\;mm{\times}4\;mm$. In order to measure the phase shifter using the probe station, two CPW pads are included at the input and output. The fabricated phase shifter showed an insertion loss of about 4.2~4.7 dB at 2 GHz band and a total $79^{\circ}$ phase change for DC control voltage from 0 to 5 V, and showed linear phase-tune characteristic as expected in the design.

A Study on New Broadband Phase Shifter using λ/8 Parallel Stubs (λ/8 병렬 스터브들을 이용한 새로운 광대역 위상 천이기에 대한 연구)

  • 엄순영;정영배;전순익;육종관;박한규
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.13 no.7
    • /
    • pp.657-666
    • /
    • 2002
  • In this paper, a new broadband phase shifter to adjust the slope of dispersive phase characteristic for frequency of transmission network was proposed. The new fundamental network consists of a fixed main line with a length of λ/2 at the center frequency and two double stubs, each with a length of λ/8 at the center frequency, which are open and shorted, respectively, and which are shunted at the edge points of the main line. Characteristic impedances of the main line and two parallel double stubs are adjusted to produce a minimum phase error and to obtain an input and output match at the desired phase shift. Especially, the proposed structure is especially suitable for a broadband phase shifter with large phase shifts more than 90$^{\circ}$, and it is operated in the octave bandwidth. To verify the usefulness of a new broadband phase shifter, each 45$^{\circ}$-, 90$^{\circ}$-, 180$^{\circ}$-bit phase shifter and 3-bit phase shifter(45$^{\circ}$-phase step), which is cascaded in series, operated at the center frequency 3 GHz were designed, fabricated and experimented. The measured results were in very close agreement with the corresponding simulation results over the bandwidth of I/O impedance match and phase error for each phase shift.

Phase shitter design and implementation of DGS using ferroelectric materials (강유전체를 이용한 DGS 구조의 위상 변위기 설계 및 구현)

  • Kim, Young-Ju;Park, Jun-Seok;Kim, Young-Tae;Kim, Sun-Hyeong;Kim, Hyeong-Seok
    • Proceedings of the KIEE Conference
    • /
    • 2004.07c
    • /
    • pp.2014-2016
    • /
    • 2004
  • In order to obtain a low-loss ferroelectric phase shifter, the reflection-type phase shifter with ferroelectric defected ground structure (DGS) resonators has been designed in this paper. The proposed phase shifter is consist of a 3-dB $90^{\circ}$ branch-line hybrid coupler and terminated reflective circuit with tunable ferroelectric DGS resonator. The ferroelectric DGS unit structure can provide high Q resonator characteristic at high frequencies. The design parameters of equivalent circuit for the tunable DGS resonator are derived by using simple circuit analysis method and three-dimensional full wave finite element method. The fabricated phase shifter has an insertion loss of better than 3.4dB at 13.5GHz.

  • PDF

Design and Implementation of Flux-Driven Waveguide Ferrite Phase Shifters (자속밀도 제어형 페라이트 도파관 변위기 설계 및 제작)

  • 김동석;박동철;이용희;김윤명
    • The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.3 no.1
    • /
    • pp.3-10
    • /
    • 1992
  • Flux-drive waveguide phase shifter is designed by twin-slab model. Measured differential phase shifts are smaller than the theoretical values by 8-9 percents. Measured insertion loss and VSWR of the phase shifter using TT73-2200 ferite are less than 0.45dB and 1.25 respectively, within pass band. The phase shifter using double-setup transformer shows wider bandwidth characteristics. Finally the reduced-height waveguide phase shifter using TT3-2900 ferrite shows very efficient suppression of higher-oreder modes.

  • PDF

Three Phase Voltage Phase Shifter Using Three Phase PWM AC/AC Buck Converter (3상 PWM AC/AC Buck 컨버터를 사용한 3상 전압 위상천이기)

  • 최남섭
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.5 no.6
    • /
    • pp.1116-1121
    • /
    • 2001
  • Phase shifter has been used as a means of power-flow control and for transient stability improvement in AC transmission system. Until now, phase shifters have been based on an injection transformer. Conventional phase shifters with tap changers require regular maintenance and allow only step-like control of the phase angle. This paper propose a three-phase phase shifter using PWM AC/AC converter, which can improve system response and control stability in the applications. This paper deals with the circuit topology, operating principle so that the features of the phase shifter will be shown through computer simulation, especially using PSIM software.

  • PDF