The Experts below are selected from a list of 7992 Experts worldwide ranked by ideXlab platform

H H Xia - One of the best experts on this subject based on the ideXlab platform.

  • an analytical model for predicting path loss in urban and suburban environments
    Personal Indoor and Mobile Radio Communications, 1996
    Co-Authors: H H Xia
    Abstract:

    An analytical propagation model has previously been developed to predict radio signal attenuation in urban and suburban environments. Most of the traditional models commonly used for macrocellular system design are empirical, which account for radio signal attenuation between base and mobile stations using a simple slope-intercept approach. Unlike the empirical models, the analytical model explicates the path loss in urban and suburban environments as a result of signal reduction due to free space wave front spreading, multiple diffraction past rows of buildings, as well as building shadowing. Since the dependence on frequency, base station Antenna Height, mobile station Antenna Height, building Height and street width are analytically explicit, this model is applicable for cellular as well as PCS applications in both macro and micro cellular environments. Good accuracy was found for this analytical model by comparing the predictions with numerous measurements made in various propagation environments. However, since the analytical model involves multiple dimension integration to calculate the signal attenuation due to multiple diffraction past rows of buildings, the model in its original format does not lend itself to be easily implemented into a radio system planning tool. To meet the needs of fast assessment of cell coverage, co-channel/adjacent channel interference, and system capacity, a simplified version of the analytical model is developed in this paper, which can be used for three different propagation scenarios with base station Antenna above, below and near the average rooftop level.

  • path loss delay spread and outage models as functions of Antenna Height for microcellular system design
    IEEE Transactions on Vehicular Technology, 1994
    Co-Authors: M J Feuerstein, Theodore S Rappaport, K L Blackard, S Y Seidel, H H Xia
    Abstract:

    This paper presents results of wide-band path loss and delay spread measurements for five representative microcellular environments in the San Francisco Bay area at 1900 MHz. Measurements were made with a wide-band channel sounder using a 100-ns probing pulse. Base station Antenna Heights of 3.7 m, 8.5 m, and 13.3 m were tested with a mobile receiver Antenna Height of 1.7 m to emulate a typical microcellular scenario. The results presented in this paper provide insight into the statistical distributions of measured path loss by showing the validity of a double regression model with a break point at a distance that has first Fresnel zone clearance for line-of-sight topographies. The variation of delay spread as a function of path loss is also investigated, and a simple exponential overbound model is developed. The path loss and delay spread models are then applied to communication system design allowing outage probabilities, based on path loss or delay spread, to be estimated for a given microcell size. >

  • path loss and delay spread models as functions of Antenna Height for microcellular system design
    Vehicular Technology Conference, 1992
    Co-Authors: K L Blackard, Theodore S Rappaport, M J Feuerstein, S Y Seidel, H H Xia
    Abstract:

    Results of wideband path loss and delay spread measurements for two representative microcellular environments in the San Francisco Bay area in the 1900 MHz band are presented. The results provide insight into the statistical distributions of measured path loss by showing the validity of a double regression model with a break point at a distance that has first Fresnel zone clearance for line-of-sight topographies. The variation of delay spread as a function of path loss is investigated, and a simple exponential overbound model is developed. The path loss and delay spread models are then applied to communication system design allowing outage probabilities, based on path loss or delay spread, to be estimated for a given microcell radius. >

Tao Jiang - One of the best experts on this subject based on the ideXlab platform.

  • The Impact of Antenna Height on the Channel Model in Indoor Industrial Scenario
    2020 IEEE CIC International Conference on Communications in China (ICCC Workshops), 2020
    Co-Authors: Tao Jiang, Jianhua Zhang, Lei Tian, Yi Zheng, Qixing Wang, Jianwu Dou
    Abstract:

    As the Industrial Internet of Things (IIoT) becomes one of the most important application scenarios in the fifth generation (5G) wireless communication system, the study for indoor industrial scenario is attracting more and more attention from the researchers. In the industrial scenario, the ceiling is much higher than the indoor scenario, thus the Antenna can be deployed in a large Height range. In 3GPP TR 38.901 standard, the path loss of NLOS case is also modeled according to the Antenna Height. In this paper, we conducted four channel measurements in a machine shop, and the Antenna Height is set as clutter-elevated and clutter-embedded in these four measured cases. It can be seen from the result that the Antenna Height has a significant impact on the path loss and the root mean square (RMS) delay spread.

  • path loss models for ieee 802 15 4 vehicle to infrastructure communications in rural areas
    IEEE Internet of Things Journal, 2018
    Co-Authors: Tao Jiang
    Abstract:

    As a promising standard to realize low data-rate, low-power, and short-range communications among wireless devices, IEEE 802.15.4 has been widely applied in wireless sensor networks, and also been intensively investigated in vehicle-to-infrastructure (V2I) communications. In this paper, we analyze the effects of Antenna Height on IEEE 802.15.4 V2I communications in rural areas. In particular, we first propose a geometry-based piecewise model to quantify the variable foliage effects. Furthermore, we show the feasibility of extending foliage loss predictions from static to mobile cases with classical empirical methods. Simulation results verify the precision of our proposed channel model in rural areas by comparing it with other channel models and realistic measurements.

  • 3GPP Standardized 5G Channel Model for IIoT Scenarios: A Survey
    IEEE Internet of Things Journal, 2026
    Co-Authors: Tao Jiang, Jianhua Zhang, Lei Tian, Yi Zheng, Jianwu Dou, Pan Tang, Henrik Asplund, Leszek Raschkowski, Raffaele D’errico, Tommi Jämsä
    Abstract:

    Industrial internet of things (IIoT) is an emerging area that fifth-generation (5G) mobile communication system penetrates industrial manufacturing applications. The indoor factory has larger space and there are a lot of metal machine tools distributed in it, which makes its radio propagation characteristics and corresponding channel models significantly different from those of the indoor office and indoor hotspot. To support the design and the evaluation of the IIoT techniques, the 3rd Generation Partnership Project (3GPP) released the first 5G IIoT standard model in October 2019. In this paper, we give a detailed explanation of this IIoT model and compare it with other indoor models. Firstly, we introduce the standardization of 3GPP IIoT channel model and its motivation. Secondly, four IIoT sub-scenarios, which are classified according to the clutter density and Antenna Height, are described. Thirdly, the potential frequency bands of 5G IIoT are summarized. Fourthly, the models of channel parameters, including the path loss and the line-of-sight (LOS) probability, the Root Mean Square (RMS) delay spread, and the angular spread, are given. Among them, the models of path loss and LOS probability take the Antenna Height and clutter density into consideration. The model of RMS delay spread changes from frequency-dependent to volume-dependent in order to catch the size variation of factories. Finally, two newly added key channel characteristics, dual mobility and absolute time of arrival, which help to describe the robot movement and positioning, are also presented.

K L Blackard - One of the best experts on this subject based on the ideXlab platform.

  • path loss delay spread and outage models as functions of Antenna Height for microcellular system design
    IEEE Transactions on Vehicular Technology, 1994
    Co-Authors: M J Feuerstein, Theodore S Rappaport, K L Blackard, S Y Seidel, H H Xia
    Abstract:

    This paper presents results of wide-band path loss and delay spread measurements for five representative microcellular environments in the San Francisco Bay area at 1900 MHz. Measurements were made with a wide-band channel sounder using a 100-ns probing pulse. Base station Antenna Heights of 3.7 m, 8.5 m, and 13.3 m were tested with a mobile receiver Antenna Height of 1.7 m to emulate a typical microcellular scenario. The results presented in this paper provide insight into the statistical distributions of measured path loss by showing the validity of a double regression model with a break point at a distance that has first Fresnel zone clearance for line-of-sight topographies. The variation of delay spread as a function of path loss is also investigated, and a simple exponential overbound model is developed. The path loss and delay spread models are then applied to communication system design allowing outage probabilities, based on path loss or delay spread, to be estimated for a given microcell size. >

  • path loss and delay spread models as functions of Antenna Height for microcellular system design
    Vehicular Technology Conference, 1992
    Co-Authors: K L Blackard, Theodore S Rappaport, M J Feuerstein, S Y Seidel, H H Xia
    Abstract:

    Results of wideband path loss and delay spread measurements for two representative microcellular environments in the San Francisco Bay area in the 1900 MHz band are presented. The results provide insight into the statistical distributions of measured path loss by showing the validity of a double regression model with a break point at a distance that has first Fresnel zone clearance for line-of-sight topographies. The variation of delay spread as a function of path loss is investigated, and a simple exponential overbound model is developed. The path loss and delay spread models are then applied to communication system design allowing outage probabilities, based on path loss or delay spread, to be estimated for a given microcell radius. >

M J Feuerstein - One of the best experts on this subject based on the ideXlab platform.

  • path loss delay spread and outage models as functions of Antenna Height for microcellular system design
    IEEE Transactions on Vehicular Technology, 1994
    Co-Authors: M J Feuerstein, Theodore S Rappaport, K L Blackard, S Y Seidel, H H Xia
    Abstract:

    This paper presents results of wide-band path loss and delay spread measurements for five representative microcellular environments in the San Francisco Bay area at 1900 MHz. Measurements were made with a wide-band channel sounder using a 100-ns probing pulse. Base station Antenna Heights of 3.7 m, 8.5 m, and 13.3 m were tested with a mobile receiver Antenna Height of 1.7 m to emulate a typical microcellular scenario. The results presented in this paper provide insight into the statistical distributions of measured path loss by showing the validity of a double regression model with a break point at a distance that has first Fresnel zone clearance for line-of-sight topographies. The variation of delay spread as a function of path loss is also investigated, and a simple exponential overbound model is developed. The path loss and delay spread models are then applied to communication system design allowing outage probabilities, based on path loss or delay spread, to be estimated for a given microcell size. >

  • path loss and delay spread models as functions of Antenna Height for microcellular system design
    Vehicular Technology Conference, 1992
    Co-Authors: K L Blackard, Theodore S Rappaport, M J Feuerstein, S Y Seidel, H H Xia
    Abstract:

    Results of wideband path loss and delay spread measurements for two representative microcellular environments in the San Francisco Bay area in the 1900 MHz band are presented. The results provide insight into the statistical distributions of measured path loss by showing the validity of a double regression model with a break point at a distance that has first Fresnel zone clearance for line-of-sight topographies. The variation of delay spread as a function of path loss is investigated, and a simple exponential overbound model is developed. The path loss and delay spread models are then applied to communication system design allowing outage probabilities, based on path loss or delay spread, to be estimated for a given microcell radius. >

Hongbo Zhu - One of the best experts on this subject based on the ideXlab platform.

  • Antenna Height dependent delay spread model under indoor stair environment for small cell deployment in future mobile communications
    Ieej Transactions on Electrical and Electronic Engineering, 2015
    Co-Authors: Yang Liu, Hongbo Zhu
    Abstract:

    A novel measurement-based Antenna-Height-dependent statistical root-mean-square (RMS) delay spread model under indoor stair environment is proposed. In this model, the RMS delay spread is described as a log-normal random variable with Antenna-Height-dependent parameters in both line-of-sight (LOS) and the non-LOS (NLOS) areas. The environmental independence of the RMS delay spread distribution is shown first. Then, the parameters of the proposed model are extracted using least-squares and maximum likelihood estimation. The accuracy of the proposed model is verified by the extensive measured data, and the mean values of the RMS delay spread are compared with those in other related works. Finally, the interdependence of RMS delay spread and the coherence bandwidth is investigated. The proposed model can be applied to the physical layer designs of small cells in future 5G and ubiquitous mobile communication systems. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.

  • Antenna Height dependent path loss model and shadowing characteristics under indoor stair environment at 2 6 ghz
    Ieej Transactions on Electrical and Electronic Engineering, 2015
    Co-Authors: Yang Liu, Hongbo Zhu
    Abstract:

    A novel path loss model under an indoor stair environment with Antenna-Height dependency at the 2.6-GHz band is proposed in this paper. In order to describe the attenuation caused by the variation of Antenna Height, a new Height attenuation factor (HAF) is added to the usual local path loss model. The path loss exponent and the Antenna-Height-dependent factor are obtained by using the least squares method. Besides, the influence of Antenna Height variation on the shadowing effects is studied, and an empirical expression of the standard deviation about Antenna Height is obtained. The proposed model is verified by several measurement results. The results show that the proposed model is effective and can be employed for the future fifth-generation (5G) ubiquitous wireless communication system design. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.

  • path loss model with Antenna Height dependency under indoor stair environment
    International Journal of Antennas and Propagation, 2014
    Co-Authors: Yang Liu, Hongbo Zhu
    Abstract:

    A novel, receiving Antenna-Height-dependent path loss model under indoor stair environment is presented. The effect of a cross-beam in the stairs is also considered. The proposed model can be applied to describe both of the line-of-sight (LOS) and the non-LOS (NLOS) cases. By using least square criterion, the parameters of proposed model are extracted. Finally, using the maximum likelihood estimation, the precision of the proposed model is evaluated by the standard deviation of shadowing.