IRS-Assisted UAV Communications with Imperfect Phase Compensation

<div>This work presents a performance analysis on unmanned aerial vehicles (UAVs) assisted wireless</div><div>communications systems, where one of the UAVs supports intelligent reflecting surfaces (IRS). As the</div><div>estimation and compensation of the end-to-end phase for each propagation path is prone to errors, imperfect</div><div>phase compensation at the IRS is taken into consideration. The performance is derived in terms of symbol</div><div>error rate (SER) and outage probability, where the phase error is modeled using the von Mises distribution.</div><div>The air-to-air (A2A) channel for</div><div>each propagation path is modeled as a single dominant line-of-sight (LoS) component, and the results are</div><div>compared to the Rician channel model. The obtained results reveal that the considered A2A model can be</div><div>used to accurately represent the A2A channel with Rician fading.</div>

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Capacity Analysis of IRS-Based UAV Communications with Imperfect Phase Compensation

10.36227/techrxiv.14000510.v1 ◽

2021 ◽

Author(s):

MOHAMMAD AHMAD Al-Jarrah ◽

Emad Alsusa ◽

Arafat Al-Dweik ◽

Daniel K. C. So

Keyword(s):

Signal To Noise Ratio ◽

Phase Error ◽

Random Variable ◽

System Capacity ◽

High Signal ◽

Capacity Analysis ◽

Capacity Loss ◽

Von Mises ◽

Reflecting Surfaces ◽

Incident Waves

<div>This paper presents the capacity analysis of unmanned aerial vehicles (UAVs) communications supported by flying intelligent reflecting surfaces (IRSs). In the considered system, some of the UAVs are equipped with an IRS panel that applies certain phase-shifts to the incident waves before being reflected to the receiving UAV. In contrast to existing work, this letter considers the effect of imperfect phase knowledge on the system capacity, where the phase error is modeled as a von Mises random variable with parameter k. Analytical results, corroborated by Monte Carlo simulations, show that the achievable capacity is dependent on the phase error, however, the capacity loss becomes negligible at high signal-to-noise ratio (SNR) and when k>6.</div>

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Millimetre wave 3-D channel modelling for next generation 5G networks

AIMS Electronics and Electrical Engineering ◽

10.3934/electreng.2022003 ◽

2022 ◽

Vol 6 (1) ◽

pp. 29-42

Author(s):

Latih Saba'neh ◽

◽

Obada Al-Khatib ◽

Keyword(s):

Channel Model ◽

Mimo System ◽

Wave Spectrum ◽

Mimo Channel ◽

Propagation Path ◽

Line Of Sight ◽

Atmospheric Effects ◽

New York University ◽

Millimetre Wave ◽

Wave Channel

<abstract><p>Millimetre wave (mm-wave) spectrum (30-300GHz) is a key enabling technology in the advent of 5G. However, an accurate model for the mm-wave channel is yet to be developed as the existing 4G-LTE channel models (frequency below 6 GHz) exhibit different propagation attributes. In this paper, a spatial statistical channel model (SSCM) is considered that estimates the characteristics of the channel in the 28, 60, and 73 GHz bands. The SSCM is used to mathematically approximate the propagation path loss in different environments, namely, Urban-Macro, Urban-Micro, and Rural-Macro, under Line-of-Sight (LOS) and Non-Line-of-Sight (NLOS) conditions. The New York University (NYU) channel simulator is utilised to evaluate the channel model under various conditions including atmospheric effects, distance, and frequency. Moreover, a MIMO system has been evaluated under mm-wave propagation. The main results show that the 60 GHz band has the highest attenuation compared to the 28 and 73 GHz bands. The results also show that increasing the number of antennas is proportional to the condition number and the rank of the MIMO channel matrix.</p></abstract>

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Capacity Analysis of IRS-Based UAV Communications with Imperfect Phase Compensation

10.36227/techrxiv.14000510 ◽

2021 ◽

Author(s):

MOHAMMAD AHMAD Al-Jarrah ◽

Emad Alsusa ◽

Arafat Al-Dweik ◽

Daniel K. C. So

Keyword(s):

Signal To Noise Ratio ◽

Phase Error ◽

Random Variable ◽

System Capacity ◽

High Signal ◽

Capacity Analysis ◽

Capacity Loss ◽

Von Mises ◽

Reflecting Surfaces ◽

Incident Waves

<div>This paper presents the capacity analysis of unmanned aerial vehicles (UAVs) communications supported by flying intelligent reflecting surfaces (IRSs). In the considered system, some of the UAVs are equipped with an IRS panel that applies certain phase-shifts to the incident waves before being reflected to the receiving UAV. In contrast to existing work, this letter considers the effect of imperfect phase knowledge on the system capacity, where the phase error is modeled as a von Mises random variable with parameter k. Analytical results, corroborated by Monte Carlo simulations, show that the achievable capacity is dependent on the phase error, however, the capacity loss becomes negligible at high signal-to-noise ratio (SNR) and when k>6.</div>

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Interference Mitigation for Visible Light Communications in Underground Mines Using Angle Diversity Receivers

Sensors ◽

10.3390/s20020367 ◽

2020 ◽

Vol 20 (2) ◽

pp. 367 ◽

Cited By ~ 6

Author(s):

Pablo Palacios Játiva ◽

Milton Román Cañizares ◽

Cesar A. Azurdia-Meza ◽

David Zabala-Blanco ◽

Ali Dehghan Firoozabadi ◽

...

Keyword(s):

Visible Light ◽

Mine Working ◽

Channel Model ◽

Underground Mining ◽

Cumulative Distribution ◽

Line Of Sight ◽

Delay Spread ◽

Noise Power ◽

Working Face ◽

Angle Diversity

This paper proposes two solutions based on angle diversity receivers (ADRs) to mitigate inter-cell interference (ICI) in underground mining visible light communication (VLC) systems, one of them is a novel approach. A realistic VLC system based on two underground mining scenarios, termed as mining roadway and mine working face, is developed and modeled. A channel model based on the direct component in line-of-sight (LoS) and reflections of non-line-of-sight (NLoS) links is considered, as well as thermal and shot noises. The design and mathematical models of a pyramid distribution and a new hemi-dodecahedral distribution are addressed in detail. The performances of these approaches, accompanied by signal combining schemes, are evaluated with the baseline of a single photo-diode in reception. Results show that the minimum lighting standards established in both scenarios are met. As expected, the root-mean-square delay spread decreases as the distance between the transmitters and receivers increases. Furthermore, the hemi-dodecahedron ADR in conjunction with the maximum ratio combining (MRC) scheme, presents the best performance in the evaluated VLC system, with a maximum user data rate of 250 Mbps in mining roadway and 120 Mbps in mine working face, received energy per bit/noise power of 32 dB and 23 dB, respectively, when the bit error rate corresponds to 10 − 4 , and finally, values of 120 dB in mining roadway and 118 dB in mine working face for signal-to-interference-plus-noise ratio are observed in a cumulative distribution function.

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Joint UAV channel modeling and power control for 5G IoT networks

EURASIP Journal on Wireless Communications and Networking ◽

10.1186/s13638-021-01988-2 ◽

2021 ◽

Vol 2021 (1) ◽

Author(s):

Xiuhua Fu ◽

Tian Ding ◽

Rongqun Peng ◽

Cong Liu ◽

Mohamed Cheriet

Keyword(s):

Energy Efficiency ◽

Power Control ◽

Channel Model ◽

Path Loss ◽

Channel Modeling ◽

Signal Propagation ◽

Spectrum Efficiency ◽

Propagation Path ◽

Control Factor ◽

The Impact

AbstractThis paper studies the communication problem between UAVs and cellular base stations in a 5G IoT scenario where multiple UAVs work together. We are dedicated to the uplink channel modeling and the performance analysis of the uplink transmission. In the channel model, we consider the impact of 3D distance and multi-UAVs reflection on wireless signal propagation. The 3D distance is used to calculate the path loss, which can better reflect the actual path loss. The power control factor is used to adjust the UAV's uplink transmit power to compensate for different propagation path losses, so as to achieve precise power control. This paper proposes a binary exponential power control algorithm suitable for 5G networked UAV transmitters and presents the entire power control process including the open-loop phase and the closed-loop phase. The effects of power control factors on coverage probability, spectrum efficiency and energy efficiency under different 3D distances are simulated and analyzed. The results show that the optimal power control factor can be found from the point of view of energy efficiency.

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A line-of-sight channel model for the 100–450 gigahertz frequency band

EURASIP Journal on Wireless Communications and Networking ◽

10.1186/s13638-021-01974-8 ◽

2021 ◽

Vol 2021 (1) ◽

Author(s):

Joonas Kokkoniemi ◽

Janne Lehtomäki ◽

Markku Juntti

Keyword(s):

Channel Model ◽

Full Range ◽

Line Of Sight ◽

Absorption Loss ◽

Radio Communication ◽

International Telecommunication Union ◽

International Telecommunication ◽

Fifth Generation ◽

Proposed Model ◽

Actual Response

AbstractThis paper documents a simple parametric polynomial line-of-sight channel model for 100–450 GHz band. The band comprises two popular beyond fifth generation (B5G) frequency bands, namely, the D band (110–170 GHz) and the low-THz band (around 275–325 GHz). The main focus herein is to derive a simple, compact, and accurate molecular absorption loss model for the 100–450 GHz band. The derived model relies on simple absorption line shape functions that are fitted to the actual response given by complex but exact database approach. The model is also reducible for particular sub-bands within the full range of 100–450 GHz, further simplifying the absorption loss estimate. The proposed model is shown to be very accurate by benchmarking it against the exact response and the similar models given by International Telecommunication Union Radio Communication Sector. The loss is shown to be within ±2 dBs from the exact response for one kilometer link in highly humid environment. Therefore, its accuracy is even much better in the case of usually considered shorter range future B5G wireless systems.

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A Phase Compensation Technique of Sampling Moiré Method for Accurate Single-Shot Phase Analysis

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.70.243 ◽

2011 ◽

Vol 70 ◽

pp. 243-248

Author(s):

Shien Ri ◽

Takashi Muramatsu ◽

Masumi Saka

Keyword(s):

Computer Simulation ◽

Phase Analysis ◽

Phase Error ◽

Linear Interpolation ◽

Small Displacement ◽

Single Shot ◽

Phase Compensation ◽

Compensation Technique ◽

Moire Method ◽

Effective Phase

Recently, a technique for fast and accurate phase analysis called sampling moiré method has been developed for measurement of small-displacement distribution. In this study, a distribution of phase error caused by linear interpolation in case with mismatch between the sampling pitch and the grating pitch is theoretically analyzed. Moreover, a technique for effective phase compensation is proposed to reduce the periodic phase error. The performance of our compensation method is validated by a computer simulation. Phase analysis can be performed more accurately even in the case that the sampling pitch does not match to the grating pitch strictly.

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