253 research outputs found
Study on 3GPP Rural Macrocell Path Loss Models for Millimeter Wave Wireless Communications
Little research has been done to reliably model millimeter wave (mmWave) path
loss in rural macrocell settings, yet, models have been hastily adopted without
substantial empirical evidence. This paper studies past rural macrocell (RMa)
path loss models and exposes concerns with the current 3rd Generation
Partnership Project (3GPP) TR 38.900 (Release 14) RMa path loss models adopted
from the International Telecommunications Union - Radiocommunications (ITU-R)
Sector. This paper shows how the 3GPP RMa large-scale path loss models were
derived for frequencies below 6 GHz, yet they are being asserted for use up to
30 GHz, even though there has not been sufficient work or published data to
support their validity at frequencies above 6 GHz or in the mmWave bands. We
present the background of the 3GPP RMa path loss models and their use of odd
correction factors not suitable for rural scenarios, and show that the
multi-frequency close-in free space reference distance (CI) path loss model is
more accurate and reliable than current 3GPP and ITU-R RMa models. Using field
data and simulations, we introduce a new close-in free space reference distance
with height dependent path loss exponent model (CIH), that predicts rural
macrocell path loss using an effective path loss exponent that is a function of
base station antenna height. This work shows the CI and CIH models can be used
from 500 MHz to 100 GHz for rural mmWave coverage and interference analysis,
without any discontinuity at 6 GHz as exists in today's 3GPP and ITU-R RMa
models.Comment: To be published in 2017 IEEE International Conference on
Communications (ICC), Paris, France, May 201
A Novel Millimeter-Wave Channel Simulator and Applications for 5G Wireless Communications
This paper presents details and applications of a novel channel simulation
software named NYUSIM, which can be used to generate realistic temporal and
spatial channel responses to support realistic physical- and link-layer
simulations and design for fifth-generation (5G) cellular communications.
NYUSIM is built upon the statistical spatial channel model for broadband
millimeter-wave (mmWave) wireless communication systems developed by
researchers at New York University (NYU). The simulator is applicable for a
wide range of carrier frequencies (500 MHz to 100 GHz), radio frequency (RF)
bandwidths (0 to 800 MHz), antenna beamwidths (7 to 360 degrees for azimuth and
7 to 45 degrees for elevation), and operating scenarios (urban microcell, urban
macrocell, and rural macrocell), and also incorporates multiple-input
multiple-output (MIMO) antenna arrays at the transmitter and receiver. This
paper also provides examples to demonstrate how to use NYUSIM for analyzing
MIMO channel conditions and spectral efficiencies, which show that NYUSIM is an
alternative and more realistic channel model compared to the 3rd Generation
Partnership Project (3GPP) and other channel models for mmWave bands.Comment: 7 pages, 8 figures, in 2017 IEEE International Conference on
Communications (ICC), Paris, May 201
Measurement-based Close-in Path Loss Modeling with Diffraction for Rural Long-distance Communications
In this letter, we investigate rural large-scale path loss models based on
the measurements in a central area of South Korea (rural area) in spring. In
particular, we develop new close-in (CI) path loss models incorporating a
diffraction component. The transmitter used in the measurement system is
located on a hill and utilizes omnidirectional antennas operating at 1400 and
2250 MHz frequencies. The receiver is also equipped with omnidirectional
antennas and measures at positions totaling 3,858 (1,262 positions for LOS and
2,596 positions for NLOS) and 4,957 (1,427 positions for LOS and 3,530
positions for NLOS) for 1400 and 2250 MHz, respectively. This research
demonstrates that the newly developed CI path loss models incorporating a
diffraction component significantly reduce standard deviations (STD) and are
independent of frequency, especially for LOS beyond the first meter of
propagation, making them suitable for use with frequencies up to a
millimeter-wave.Comment: 5 pages, 5 figure
Receiver diversity with selection combining for drone communication around buildings at frequency 10 GHz
The communication network for cellular network keep development. This research analyzed about cellular network was used drone network. The mobile drone used frequency at 10 GHz for communication. The mobile drone moved around buildings. Buildings were used high variation. Base Station placed around building. This research was using macro diversity Base Station, variation building, variation modulation, and variation height of drone trajectory. Macro diversity mechanism used for that two Base Station. Selection Combining (SC) method was used for that macro diversity mechanism. The modulation communication based from Adaptive Modulation and Coding (AMC). Adaptive Modulation and Coding (AMC) was used Modulation and coding scheme (MCS). Modulation was used QPSK, 16 QAM, and 64 QAM. As the result described signal to noise ratio (SNR) at every node communication, probability MCS, and percentage coverage of drone trajectory. MCS probability for 64 QAM become increased with selection combining method. The percentages coverage of drone trajectory was obtained 77.2% of the first BS, 66.8% of the second BS, and 87.2% with SC method.The communication network for cellular network keep development. This research analyzed about cellular network was used drone network. The mobile drone used frequency at 10 GHz for communication. The mobile drone moved around buildings. Buildings were used high variation. Base Station placed around building. This research was using macro diversity Base Station, variation building, variation modulation, and variation height of drone trajectory. Macro diversity mechanism used for that two Base Station. Selection Combining (SC) method was used for that macro diversity mechanism. The modulation communication based from Adaptive Modulation and Coding (AMC). Adaptive Modulation and Coding (AMC) was used Modulation and coding scheme (MCS). Modulation was used QPSK, 16 QAM, and 64 QAM. As the result described signal to noise ratio (SNR) at every node communication, probability MCS, and percentage coverage of drone trajectory. MCS probability for 64 QAM become increased with selection combining method. The percentages coverage of drone trajectory was obtained 77.2% of the first BS, 66.8% of the second BS, and 87.2% with SC method
Millimeter Wave MIMO Channel Estimation Based on Adaptive Compressed Sensing
Multiple-input multiple-output (MIMO) systems are well suited for
millimeter-wave (mmWave) wireless communications where large antenna arrays can
be integrated in small form factors due to tiny wavelengths, thereby providing
high array gains while supporting spatial multiplexing, beamforming, or antenna
diversity. It has been shown that mmWave channels exhibit sparsity due to the
limited number of dominant propagation paths, thus compressed sensing
techniques can be leveraged to conduct channel estimation at mmWave
frequencies. This paper presents a novel approach of constructing beamforming
dictionary matrices for sparse channel estimation using the continuous basis
pursuit (CBP) concept, and proposes two novel low-complexity algorithms to
exploit channel sparsity for adaptively estimating multipath channel parameters
in mmWave channels. We verify the performance of the proposed CBP-based
beamforming dictionary and the two algorithms using a simulator built upon a
three-dimensional mmWave statistical spatial channel model, NYUSIM, that is
based on real-world propagation measurements. Simulation results show that the
CBP-based dictionary offers substantially higher estimation accuracy and
greater spectral efficiency than the grid-based counterpart introduced by
previous researchers, and the algorithms proposed here render better
performance but require less computational effort compared with existing
algorithms.Comment: 7 pages, 5 figures, in 2017 IEEE International Conference on
Communications Workshop (ICCW), Paris, May 201
Feasibility, Architecture and Cost Considerations of Using TVWS for Rural Internet Access in 5G
The cellular technology is mostly an urban technology that has been unable to serve rural areas well. This is because the traditional cellular models are not economical for areas with low user density and lesser revenues. In 5G cellular networks, the coverage dilemma is likely to remain the same, thus widening the rural-urban digital divide further. It is about time to identify the root cause that has hindered the rural technology growth and analyse the possible options in 5G architecture to address this issue. We advocate that it can only be accomplished in two phases by sequentially addressing economic viability followed by performance progression. We deliberate how various works in literature focus on the later stage of this ‘two-phase’ problem and are not feasible to implement in the first place. We propose the concept of TV band white space (TVWS) dovetailed with 5G infrastructure for rural coverage and show that it can yield cost-effectiveness from a service provider’s perspective
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