IEICE Electronics Express
Online ISSN : 1349-2543
ISSN-L : 1349-2543
Volume 17, Issue 16
Displaying 1-5 of 5 articles from this issue
LETTER
  • Yi Yang, Di Li, Chanrong Jiang, Yuqian Liu, Yintang Yang
    Article type: LETTER
    Subject area: Integrated circuits
    2020 Volume 17 Issue 16 Pages 20200193
    Published: August 25, 2020
    Released on J-STAGE: August 25, 2020
    Advance online publication: July 27, 2020
    JOURNAL FREE ACCESS

    This paper presents an optimized Fully-Passive Noise-Shaping Successive Approximation Register (FPNS-SAR) Analog-to-Digital Converter (ADC) with passive gain and integration capacitor reuse techniques. Instead of using multi-input-pair comparator with active gain in traditional Cascaded Integrator Feed-Forward (CIFF) structure, 1-input-pair comparator with passive gain is adopted in this paper to reduce power consumption and kick-back noise. The proposed FPNS-SAR ADC was implemented with standard 65-nm CMOS process. With the oversampling ratio (OSR) of 8, the simulation results realize 79.3dB peak SNDR and 94dB peak SFDR at 6.25MHz input signal bandwidth and 100MHz sampling frequency. The proposed ADC consumes 1.245mW at 1.2V supply voltage. The calculated FOMw and FOMs are 13.2fJ/conv.-step and 176.3dB, respectively.

    Download PDF (877K)
  • Jun Mochizuki, Keizo Inagaki, Guo-Wei Lu, Takahide Sakamoto, Yuki Yosh ...
    Article type: LETTER
    Subject area: Optical hardware
    2020 Volume 17 Issue 16 Pages 20200216
    Published: August 25, 2020
    Released on J-STAGE: August 25, 2020
    Advance online publication: July 28, 2020
    JOURNAL FREE ACCESS

    We proposed a variable linewidth light source using random walk phase noise. As a demonstration, the impact of the laser linewidth on the error-vector magnitude performance in the optical QPSK transmission was evaluated by using the proposed laser source experimentally, where the linewidth tunable range was from 40kHz to 5MHz.

    Download PDF (565K)
  • Guohua Liu, Guoxiang Zhou, Sudong Li, Zhiwei Zhang, Cantianci Guo, Zhi ...
    Article type: LETTER
    Subject area: Microwave and millimeter wave devices, circuits, and modules
    2020 Volume 17 Issue 16 Pages 20200226
    Published: August 25, 2020
    Released on J-STAGE: August 25, 2020
    Advance online publication: August 04, 2020
    JOURNAL FREE ACCESS

    This paper presents a multi-octave broadband continuous power amplifier based on the simplified real frequency method. By analyzing the load-pull impedance trajectory along with frequency increase at both ends of the transistor’s input and output, the input impedance value of the matching circuit can be more coincident with the pull data in the wide band range, which meets the requirement of expanding the bandwidth of the power amplifier. Meanwhile, combining with simplified real frequency method, it can greatly simplify the process of designing broadband matching network. In order to verify the validity of the theory, the power amplifier is designed and fabricated. The measured results show that the maximum output power reached 42.5dBm and the drain efficiency is from 63% to 71% in the 1-3.2 GHz frequency band.

    Download PDF (8954K)
  • Ranepura Hewage Neranjith, Yuya Shoji, Tetsuya Mizumoto
    Article type: LETTER
    Subject area: Integrated optoelectronics
    2020 Volume 17 Issue 16 Pages 20200227
    Published: August 25, 2020
    Released on J-STAGE: August 25, 2020
    Advance online publication: July 29, 2020
    JOURNAL FREE ACCESS

    We propose and demonstrate the fundamental operation of a novel on-chip microring resonator-type serial-to-parallel conversion scheme for all-optical label processing. We left out a delay between the simultaneously implemented pump pulses and probe bits to be extracted. This enabled us to utilize free-carrier dispersion effect to concurrently blue shift the resonance spectra of the microring resonators at low pump power, and avoid nonlinear loss due to two-photon absorption. We successfully extracted two consecutive bits of probe packets into separate waveguides and verified the potential of our scheme in the intended application.

    Download PDF (622K)
  • Deng-Hui Li, Fu-Shun Zhang, Guo-Jun Xie, Hongyin Zhang, Yi Zhao
    Article type: LETTER
    Subject area: Microwave and millimeter wave devices, circuits, and modules
    2020 Volume 17 Issue 16 Pages 20200233
    Published: August 25, 2020
    Released on J-STAGE: August 25, 2020
    Advance online publication: July 29, 2020
    JOURNAL FREE ACCESS

    A miniaturized ultra-wideband (UWB) multiple-input multiple-output (MIMO) Vivaldi antenna with dual band-rejected performance is introduced and fabricated in this letter. The method of loading absorption resistors on the ground is used to realize miniaturization. In order to improve the isolation between the two ports, a T-slot is etched between two Vivaldi elements. At last, by etching the split ring resonator (SRR) slits on the ground, and placing two split ring resonators (SRRs) near the feed balun structures, the dual band-rejected characteristics are achieved. Then the designed antenna prototype is fabricated and measured, and the measured results show that the operating frequency of the proposed antenna is 2.5-12.0 GHz, and the dual-rejected bands are 5.1-5.9 GHz and 6.6-7.1 GHz respectively, and the isolation between the two ports is more than 15 dB over the UWB range (3.1-10.6 GHz), the size of the designed antenna is only 26 × 24.5 × 0.6 mm3.

    Download PDF (1984K)
feedback
Top