Measuring the Impact of Beamwidth on the Correlation Distance of 60 GHz Indoor and Outdoor Channels

The changing climate has introduced new and unique challenges and threats to humans and their environment. Urban dwellers in particular have suffered from increased levels of heat stress, and the situation is predicted to continue to worsen in the future. Attention toward urban climate change adaptation has increased more than ever before, but previous studies have focused on indoor and outdoor temperature patterns separately. The objective of this research is to assess the indoor and outdoor temperature patterns of different urban settlements. Remote sensing data, together with air temperature data collected with temperature data loggers, were used to analyze land surface temperature (outdoor temperature) and air temperature (indoor temperature). A hot and cold spot analysis was performed to identify the statistically significant clusters of high and low temperature data. The results showed a distinct temperature pattern across different residential units. Districts with dense urban settlements show a warmer outdoor temperature than do more sparsely developed districts. Dense urban settlements show cooler indoor temperatures during the day and night, while newly built districts show cooler outdoor temperatures during the warm season. Understanding indoor and outdoor temperature patterns simultaneously could help to better identify districts that are vulnerable to heat stress in each city. Recognizing vulnerable districts could minimize the impact of heat stress on inhabitants.

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A study about signal variation with minor receiver displacement in a meeting room at 60 GHz: measurements and simulations

EURASIP Journal on Wireless Communications and Networking ◽

10.1186/s13638-021-01965-9 ◽

2021 ◽

Vol 2021 (1) ◽

Author(s):

Muhammad Usman Sheikh ◽

Kalle Ruttik ◽

Riku Jäntti ◽

Jyri Hämäläinen

Keyword(s):

Power Level ◽

Three Dimensional ◽

60 Ghz ◽

System Configuration ◽

Conference Room ◽

Channel Characteristics ◽

Received Power ◽

Simulation Results ◽

Small Change ◽

The Impact

AbstractThe aim of this work is to study the impact of small receiver displacement on a signal propagation in a typical conference room environment at a millimeter wave frequency of 60 GHz. While channel measurements provide insights on the propagation phenomena, their use for the wireless system performance evaluation is challenging. Whereas, carefully executed three-dimensional ray tracing (RT) simulations represent a more flexible option. Nevertheless, a careful validation of simulation methodology is needed. The first target of this article is to highlight the benefits of an in-house built three-dimensional RT tool at 60 GHz and shows the effectiveness of simulations in predicting different characteristics of the channel. To validate the simulation results against the measurements, two different transmitter (Tx) positions and antenna types along with ten receiver (Rx) positions are considered in a typical conference room. In first system configuration, an omnidirectional antenna is placed in the middle of the table, while in the second system configuration a directed horn antenna is located in the corner of the meeting room. After validating the simulation results with the measurement data, in the second part of this work, the impact of a small change, i.e., 20 cm in the receiver position, is studied. To characterize the impact, we apply as performance indicators the received power level, root mean square delay spread (RMS-DS) and RMS angular spread (RMS-AS) in azimuth plane. The channel characteristics are considered with respect to the direct orientation (DO), i.e., the Rx antenna is directed toward the strongest incoming path. Different antenna configurations at the Tx and Rx side are applied to highlight the role of antenna properties on the considered channel characteristics. Especially, in the second system configuration the impact of different antenna half power beamwidth on different considered channel characteristics is highlighted through acquired simulation results. The validation of results shows the RMS error of only 2–3 dB between the measured and simulated received power levels for different Tx configurations in the direction of DO. Results indicate that only a small change of the Rx position may result a large difference in the received power level even in the presence of line-of-sight between the Tx and Rx. It is found that the STD of received power level across the room increases with the decrease in HPBW of the antenna. As can be expected, directed antennas offer lower value of RMS-DS and RMS-AS compared with isotropic antenna.

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Personal Exposure to BC, PM and NO2 in the Paris Region Measured by Portable Sensors Worn by Volunteers

Toxics ◽

10.3390/toxics10010033 ◽

2022 ◽

Vol 10 (1) ◽

pp. 33

Author(s):

Baptiste Languille ◽

Valérie Gros ◽

Bonnaire Nicolas ◽

Cécile Honoré ◽

Anne Kaufmann ◽

...

Keyword(s):

Large Scale ◽

Road Traffic ◽

Personal Exposure ◽

Portable Sensors ◽

Promising Solution ◽

Field Campaigns ◽

Paris Region ◽

The Impact ◽

First Time ◽

Indoor And Outdoor

Portable sensors have emerged as a promising solution for personal exposure (PE) measurement. For the first time in Île-de-France, PE to black carbon (BC), particulate matter (PM), and nitrogen dioxide (NO2) was quantified based on three field campaigns involving 37 volunteers from the general public wearing the sensors all day long for a week. This successful deployment demonstrated its ability to quantify PE on a large scale, in various environments (from dense urban to suburban, indoor and outdoor) and in all seasons. The impact of the visited environments was investigated. The proximity to road traffic (for BC and NO2), as well as cooking activities and tobacco smoke (for PM), made significant contributions to total exposure (up to 34%, 26%, and 44%, respectively), even though the time spent in these environments was short. Finally, even if ambient outdoor levels played a role in PE, the prominent impact of the different environments suggests that traditional ambient monitoring stations is not a proper surrogate for PE quantification.

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Impact of Process Tolerances on the Performance of Bond Wire Antennas at RF/Microwave Frequencies

International Symposium on Microelectronics ◽

10.4071/isom-2011-tha1-paper7 ◽

2011 ◽

Vol 2011 (1) ◽

pp. 000914-000920

Author(s):

Ivan Ndip ◽

Abdurrahman Öz ◽

Christian Tschoban ◽

Stefan Schmitz ◽

Martin Schneider-Ramelow ◽

...

Keyword(s):

Resonance Frequency ◽

Wire Antenna ◽

60 Ghz ◽

Planar Antennas ◽

Microwave Frequencies ◽

Bond Wires ◽

Bond Wire ◽

Wire Antennas ◽

The Impact ◽

Rf Microwave

Due to the multitude of advantages bond wire antennas have over conventional planar antennas (especially on-chip planar antennas), they have received much research attention within the last four years. The focus of the contributions made so far has been on exploiting different configurations of single-element and array bond wire antennas for short-range applications at RF/microwave frequencies. However, the effects of process tolerances of bond wires on the radiation characteristics of bond wire antennas have not been studied in published literature. Therefore in this paper, we investigate the impact of up to 20% fluctuations in the parameters of bond wires on the performance of 42 GHz and 60 GHz bond wire antennas. Our results reveal that the length and radius of bond wires are the most and least sensitive parameters, respectively. Furthermore, the severity of the impact of process tolerances depends on the impedance bandwidth of the original antenna, before considering the tolerances. For example, a 10% change in the length of a bond wire causes the resonance frequency of a 42 GHz antenna to be shifted out of the specified 3GHz bandwidth (40.5 GHz–43.5 GHz) required for point-to-point communication. However, although a 10% change in length of a bond wire yields a 2.5 GHz shift in the resonance frequency of a 60 GHz bond wire antenna, it doesn’t completely detune the antenna because of the original 6 GHz bandwidth available, prior to the fluctuation. Therefore, to prevent the impact of process tolerances from severely degrading the performance bond wire antennas, these antennas should be designed to have larger bandwidths than specified. For experimental verification, a bond wire antenna was designed, fabricated and measured. Very good correlation was obtained between measurement and simulation.

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Performance Evaluation and Interference Characterization of Wireless Sensor Networks for Complex High-Node Density Scenarios

Proceedings ◽

10.3390/ecsa-5-05729 ◽

2018 ◽

Vol 4 (1) ◽

pp. 28

Author(s):

Mikel Celaya-Echarri ◽

Leyre Azpilicueta ◽

Peio Lopez-Iturri ◽

Erik Aguirre ◽

Francisco Falcone

Keyword(s):

Wireless Sensor Networks ◽

Wave Propagation ◽

Sensor Networks ◽

Radio Wave ◽

Radio Wave Propagation ◽

Outdoor Environment ◽

Wireless Sensor ◽

5 Ghz ◽

The Impact ◽

Indoor And Outdoor

The uncontainable future development of smart regions, as a set of smart cities’ assembled networks, is directly associated with a growing demand of full interactive and connected ubiquitous smart environments. To achieve this goal of global connection, a large number of transceivers and multiple wireless systems will be involved to provide user services and applications (i.e., Ambient Assisted Living, emergency situations, e-health monitoring, or Intelligent Transportation Systems) anytime and anyplace, regardless of the devices, networks, or systems used. Adequate, efficient, and effective radio wave propagation tools, methodologies, and analyses in complex environments (indoor and outdoor) are crucial to prevent communication limitations such as coverage, capacity, speed, or channel interferences due to nodes’ density or channel restrictions. In this work, radio wave propagation characterization in an urban indoor and outdoor environment, at ISM 2.4 GHZ and 5 GHz Wireless Sensor Networks (WSNs), has been assessed. The selected scenario is an auditorium placed in a free open area surrounded by inhomogeneous vegetation. User density within the scenario, in terms of inherent transceivers density, poses challenges to the overall system operation, given by multiple node operation which increases overall interference levels. By means of an in-house developed 3D ray launching algorithm, the impact of variable density wireless sensor network operation within this complex scenario is presented. This analysis and the proposed simulation methodology can lead in an adequate interference characterization, considering conventional transceivers as well as wearables, which provide suitable information for the overall network performance in complex crowded indoor and outdoor scenarios.

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The impact of household air cleaners on the oxidative potential of PM2.5 and the role of metals and sources associated with indoor and outdoor exposure

Environmental Research ◽

10.1016/j.envres.2019.108919 ◽

2020 ◽

Vol 181 ◽

pp. 108919 ◽

Cited By ~ 6

Author(s):

Collin Brehmer ◽

Christina Norris ◽

Karoline K. Barkjohn ◽

Mike H. Bergin ◽

Junfeng Zhang ◽

...

Keyword(s):

Outdoor Exposure ◽

Oxidative Potential ◽

Air Cleaners ◽

The Impact ◽

Indoor And Outdoor

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Indoor and outdoor frequency measurements for MM-waves in the range of 60 GHz

VTC '98. 48th IEEE Vehicular Technology Conference. Pathway to Global Wireless Revolution (Cat. No.98CH36151) ◽

10.1109/vetec.1998.686638 ◽

2002 ◽

Cited By ~ 13

Author(s):

D.M. Matic ◽

H. Harada ◽

R. Prasad

Keyword(s):

60 Ghz ◽

Frequency Measurements ◽

Mm Waves ◽

Indoor And Outdoor

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New Design of 60 GHz MIMO 2x4 Patch Rectangular Antenna Array for Wireless Gigabit (Wi-Gig) Application

International Journal of Electrical, Energy and Power System Engineering ◽

10.31258/ijeepse.2.1.6-9 ◽

2019 ◽

Vol 2 (1) ◽

pp. 6-9

Author(s):

Yusnita Rahayu

Keyword(s):

Return Loss ◽

Simulation Software ◽

Propagation Loss ◽

60 Ghz ◽

Broad Bandwidth ◽

High Data ◽

Rectangular Patch ◽

Fifth Generation ◽

The World ◽

Indoor And Outdoor

Nowadays, most antenna researchers over the world are focusing on the design of the antenna for the fifth generation (5G) application (indoor and outdoor). High intensive research on 60 GHz antenna for high data rate indoor communication is becoming a trending topic. The high propagation loss at this band is the most challenging. The antenna needs to have higher gain to overcome the loss. Such antenna designs have been proposed recently. This paper, a new MIMO 2x4 patch rectangular antenna operating at 60 GHz is designed for Wi-Gig application. The rectangular patch antenna has 1.75 mm x 1.54 mm of size, printed on Rogers Duroid RT 5880 substrate, the dielectric constant of 2.20 and loss tangent of 0,0009. The antenna was designed and simulated using CST simulation software. The simulated return loss showed a very consistent characteristic. The return loss reached −30 dB at 60 GHz. The broad bandwidth obtained is 4.3 GHz concerning -10 dB. The omnidirectional radiation pattern with 13.4 dBi of gain is obtained. This antenna meets the Wi-Gig requirement.

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Wearable Inertial Gait Algorithms: Impact of Wear Location and Environment in Healthy and Parkinson’s Populations

Sensors ◽

10.3390/s21196476 ◽

2021 ◽

Vol 21 (19) ◽

pp. 6476

Author(s):

Yunus Celik ◽

Sam Stuart ◽

Wai Lok Woo ◽

Alan Godfrey

Keyword(s):

Gait Analysis ◽

Inertial Sensors ◽

Lower Back ◽

Outdoor Environments ◽

Outdoor Walking ◽

Absolute Agreement ◽

Walking Environment ◽

Indoor And Outdoor Environments ◽

The Impact ◽

Indoor And Outdoor

Wearable inertial measurement units (IMUs) are used in gait analysis due to their discrete wearable attachment and long data recording possibilities within indoor and outdoor environments. Previously, lower back and shin/shank-based IMU algorithms detecting initial and final contact events (ICs-FCs) were developed and validated on a limited number of healthy young adults (YA), reporting that both IMU wear locations are suitable to use during indoor and outdoor gait analysis. However, the impact of age (e.g., older adults, OA), pathology (e.g., Parkinson′s Disease, PD) and/or environment (e.g., indoor vs. outdoor) on algorithm accuracy have not been fully investigated. Here, we examined IMU gait data from 128 participants (72-YA, 20-OA, and 36-PD) to thoroughly investigate the suitability of ICs-FCs detection algorithms (1 × lower back and 1 × shin/shank-based) for quantifying temporal gait characteristics depending on IMU wear location and walking environment. The level of agreement between algorithms was investigated for different cohorts and walking environments. Although mean temporal characteristics from both algorithms were significantly correlated for all groups and environments, subtle but characteristically nuanced differences were observed between cohorts and environments. The lowest absolute agreement level was observed in PD (ICC2,1 = 0.979, 0.806, 0.730, 0.980) whereas highest in YA (ICC2,1 = 0.987, 0.936, 0.909, 0.989) for mean stride, stance, swing, and step times, respectively. Absolute agreement during treadmill walking (ICC2,1 = 0.975, 0.914, 0.684, 0.945), indoor walking (ICC2,1 = 0.987, 0.936, 0.909, 0.989) and outdoor walking (ICC2,1 = 0.998, 0.940, 0.856, 0.998) was found for mean stride, stance, swing, and step times, respectively. Findings of this study suggest that agreements between algorithms are sensitive to the target cohort and environment. Therefore, researchers/clinicians should be cautious while interpreting temporal parameters that are extracted from inertial sensors-based algorithms especially for those with a neurological condition.

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Penetration Loss at 60 GHz for Indoor-to-Indoor and Outdoor-to-Indoor Mobile Scenarios*

2020 14th European Conference on Antennas and Propagation (EuCAP) ◽

10.23919/eucap48036.2020.9135581 ◽

2020 ◽

Author(s):

Sung Yun Jun ◽

Derek Caudill ◽

Jack Chuang ◽

Peter B. Papazian ◽

Anuraag Bodi ◽

...

Keyword(s):

60 Ghz ◽

Penetration Loss ◽

Indoor And Outdoor

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