IEICE Communications Express
Online ISSN : 2187-0136
ISSN-L : 2187-0136
Volume 3, Issue 1
Displaying 1-6 of 6 articles from this issue
  • Ruchaneeya Leepila, Eiji Oki, Naoto Kishi
    Article type: LETTER
    2014 Volume 3 Issue 1 Pages 1-6
    Published: January 09, 2014
    Released on J-STAGE: January 09, 2014
    This letter proposes a design scheme for the power-efficient network with partial bandwidth path protection. The network with the proposed scheme utilizes resources efficiently, which leads to less power consumption. This scheme employs a Linear Programming (LP) approach to minimize power consumption by considering the number of active devices and capacity consumption. Simulations show that, with the partial bandwidth path protection, the proposed scheme saves more power than the conventional scheme, which minimizes the power consumption relying on capacity consumption.
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  • Cheng-Chang Chen, Chia-Mei Peng, I-Fong Chen, Ching-Wen Hsue
    Article type: LETTER
    2014 Volume 3 Issue 1 Pages 7-12
    Published: January 10, 2014
    Released on J-STAGE: January 10, 2014
    In this letter, it is shown that the one fifth wavelength radiator combines with a printed ground-line which protrudes from ground-plane jointly with parasitic metal-loading, which can be used to control the near-fields of a mobile phone antenna. The human’s hand and head effect on impedance bandwidth and radiation characteristics of the proposed antenna is studied. The input power of 24dBm in CDMA, GSM and WCDMA bands, and the input power of 21dBm in DCS and PCS bands all meet the specific absorption rate (SAR) limit of 1.6mW/g and hearing aid compatibility (HAC) of M3 and M4 level.
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  • Liang Han, Ying Liu, Shihai Shao, Youxi Tang
    Article type: LETTER
    2014 Volume 3 Issue 1 Pages 13-19
    Published: January 15, 2014
    Released on J-STAGE: January 15, 2014
    In this letter, we investigate the effect of correlated lognormal shadowing on the outage probability of decode-and-forward (DF) cooperative diversity systems. Since there is no closed-form expression for the outage probability, we present a numerical approach to evaluate the outage probability by using a decorrelating transformation and Gaussian-Hermite integration technique. The numerical results verify that our proposed approach is accurate, and show that the correlation coefficients and standard deviations of shadowing have a significant impact on the outage performance.
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  • XianMing Xie
    Article type: LETTER
    2014 Volume 3 Issue 1 Pages 20-26
    Published: January 21, 2014
    Released on J-STAGE: January 21, 2014
    This paper presents an improved phase unwrapping algorithm by combining an unscented KALMAN filter (UKF) and a joint phase slope estimator and a conventional path-following strategy. This algorithm is able to accurately unwrap seriously noisy wrapped phase images by applying the UKF to perform phase noise suppression and phase unwrapping at the same time. Results obtained from synthetic data validate the effectiveness of the proposed method.
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  • Irma Zakia, Suhartono Tjondronegoro, Iskandar, Adit Kurniawan
    Article type: LETTER
    2014 Volume 3 Issue 1 Pages 27-32
    Published: January 24, 2014
    Released on J-STAGE: January 24, 2014
    The tracking Mean Square Error (MSE) of the least squares (LS) Multiple Input Multiple Output (MIMO) channel estimation in rician flat fading channel is derived in closed-form, which is then verified by Monte Carlo simulation. The channel accomodates applications where the elevation angle between the transmitter and the receiver dictates the doppler shift of the Line of Sight (LOS) component, as encountered in communications from satellite or High Altitude Platform (HAP) to a moving mobile. A higher tracking loss is revealed as the mobile travels to a lower elevation angle.
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  • Yu Nakayama
    Article type: LETTER
    2014 Volume 3 Issue 1 Pages 33-38
    Published: January 27, 2014
    Released on J-STAGE: January 27, 2014
    With Shortest Path Bridging MAC (SPBM), access networks can be flexibly constructed on demand. The shortest path transmission is realized without any blocking port in any network topology. However, the paths of many flows can overlap on specific links and this results in congestion. It is important to avoid congestion by selecting the optimal path for each flow. This paper proposes a path selection algorithm for SPBM. The proposed algorithm adjusts the path selection probabilities of equal cost trees (ECTs) based on the amount of traffic expected on each link. It efficiently utilizes links and improves throughput fairness.
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