PoliSave: Efficient Power Management of Campus PCs

In this paper we study the power consumption of networked devices in a large Campus network, focusing mainly on PC usage. We first define a methodology to monitor host power state, which we then apply to our Campus network. Results show that typically people refrain from turning off their PC during non-working hours so that more than 1500 PCs are always powered on, causing a large energy waste. We then design PoliSave, a simple web-based architecture which allows users to schedule power state of their PCs, avoiding the frustration of wasting long power-down and bootstrap times of today PCs. By exploiting already available technologies like Wake-On-Lan, Hibernation and Web services, PoliSave reduces the average PC uptime from 15.9h to 9.7h during working days, generating an energy saving of 0.6kW/h per PC per day, or a saving of more than 250,000 Euros per year considering our Campus Universit

Measuring the impact of ICNIRP vs. stricter-than-ICNIRP exposure limits on QoS and EMF from cellular networks

The installation of new equipment (Base Stations, BSs) during the planning phase of a cellular network (including 5G BSs) is governed by exposure limits in terms of allowable ElectroMagnetic Field (EMF) levels. The exposure limits can be either defined by (i) international bodies (e.g., ICNIRP) or (ii) national regulations imposing limits stricter than (i). In this work, we compare the impact of ICNIRP vs. stricter-than-ICNIRP exposure regulations on the Quality of Service (QoS) and EMF. To this aim, we perform a large-scale measurement campaign in one scenario in Spain subject to ICNIRP regulations and another one in Italy subject to EMF limits stricter than ICNIRP ones. Both the scenarios are characterized by similar exposure conditions, comparable user density, and common 4G performance targets by the operators. Results, obtained by measuring QoS and EMF at selected locations, reveal that the QoS in the scenario subject to strict EMF limits is heavily worsened compared to the one in which ICNIRP-based limits are enforced. Clearly, the scenario with strict EMF limits presents a lower level exposure over the territory compared to the one imposing ICNIRP limits

An Economic Feasibility Model for Sustainable 5G Networks in Rural Dwellings of South Africa

Numerous factors have shown Internet-based technology to be a key enabler in achieving the sustainable development goals (SDG), as well as narrowing the divide between the global north and south. For instance, smart farming, remote/online learning, and smart grids can be used to, respectively, address SDGs 1 and 2 (ending poverty and hunger), 3 (quality education), and 7 and 9 (energy and infrastructure development). Though such Internet-based solutions are commonplace in the global north, they are missing or sparsely available in global south countries. This is due to several factors including underdevelopment, which dissuades service providers from investing heavily in infrastructure for providing capable Internet solutions such as 5G networks in these regions. This paper presents a study conducted to evaluate the feasibility of deploying 5G networks in the rural dwellings of South Africa at affordable rates, which would then serve as a pre-cursor for deploying solutions to improve lives and achieve the SDGs. The study evaluates the economic viability of a hybrid network model which combines terrestrial and aerial networks to provide 5G coverage in rural areas. The feasibility study reveals that such a network can be engineered at low monthly subscription fees to the end users and yield good returns to the service providers in rural areas; however, for large but sparsely populated suburban locations, the traditional terrestrial network with base stations is more suitable

Energy-Aware Base Stations: The Effect of Planning, Management, and Femto Layers

We compare the performance of three base station management schemes on three different network topologies. In addition, we explore the effect of offloading traffic to heterogeneous femtocell layer upon energy savings taking into account the increase of base station switch-off time intervals. Fairness between mobile operator and femtocell owners is maintained since current femtocell technologies present flat power consumption curves with respect to served traffic. We model two different user-to-femtocell association rules in order to capture realistic and maximum gains from the heterogeneous network. To provide accurate findings and a holistic overview of the techniques, we explore a real urban district where channel estimations and power control are modeled using deterministic algorithms. Finally, we explore energy efficiency metrics that capture savings in the mobile network operator, the required watts per user and watts per bitrate. It is found that the newly established pseudo distributed management scheme is the most preferable solution for practical implementations and together with the femotcell layer the network can handle dynamic load control that is regarded as the basic element of future demand response programs

Will the Proliferation of 5G Base Stations Increase the Radio-Frequency 'Pollution'?

A common concern among the population is that installing new 5G Base Stations (BSs) over a given geographic region may result in an uncontrollable increase of Radio-Frequency 'Pollution' (RFP). To face this dispute in a way that can be understood by the layman, we develop a very simple model, which evaluates the RFP at selected distances between the user and the 5G BS locations. We then obtain closed-form expressions to quantify the RFP increase/decrease when comparing a pair of alternative 5G deployments. Results show that a dense 5G deployment is beneficial to the users living in proximity to the 5G BSs, with an abrupt decrease of RFP (up to three orders of magnitude) compared to a sparse deployment. We also analyze scenarios where the user equipment minimum detectable signal threshold is increased, showing that in such cases a (slight) increase of RFP may be experienced

Is It Safe Living in the Vicinity of Cellular Towers? Analysis of Long-Term Human EMF Exposure at Population Scale

We focus on the ElectroMagnetic Field (EMF) exposure safety for people living in the vicinity of cellular towers. To this aim, we analyze a large dataset of long-term EMF measurements collected over almost 20 years in more than 2000 measurement points spread over an Italian region. We evaluate the relationship between EMF exposure and the following factors: (i) distance from the closest installation(s), (ii) type of EMF sources in the vicinity, (iii) Base Station (BS) technology, and (iv) EMF regulation updates. Overall, the exposure levels from BSs in the vicinity are below the Italian EMF limits, thus ensuring safety for the population. Moreover, BSs represent the lowest exposure compared to Radio/TV repeaters and other EMF sources. However, the BS EMF exposure in proximity to users exhibits an increasing trend over the last years, which is likely due to the pervasive deployment of multiple technologies and to the EMF regulation updates. As a side consideration, if the EMF levels continue to increase with the current trends, the EMF exposure in proximity to BSs will saturate to the maximum EMF limit by the next 20 years at a distance of 30 meters from the closest BS

'Pencil Beamforming Increases Human Exposure to ElectroMagnetic Fields': True or False?

According to a very popular belief-very widespread among non-scientific communities-the exploitation of narrow beams, a.k.a. 'pencil beamforming', results in a prompt increase of exposure levels radiated by 5G Base Stations (BSs). To face such concern with a scientific approach, in this work we propose a novel localization-enhanced pencil beamforming technique, in which the traffic beams are tuned in accordance with the uncertainty localization levels of User Equipment (UE). Compared to currently deployed beamforming techniques, which generally employ beams of fixed width, we exploit the localization functionality made available by the 5G architecture to synthesize the direction and the width of each pencil beam towards each served UE. We then evaluate the effectiveness of pencil beamforming in terms of ElectroMagnetic Field (EMF) exposure and UE throughput levels over different realistic case-studies. Results, obtained from a publicly released open-source simulator, dispel the myth: the adoption of localization-enhanced pencil beamforming triggers a prompt reduction of exposure w.r.t. other alternative techniques, which include e.g., beams of fixed width and cellular coverage not exploiting beamforming. The EMF reduction is achieved not only for the UE that are served by the pencil beams, but also over the whole territory (including the locations in proximity to the 5G BS). In addition, large throughput levels-adequate for most of 5G services-can be guaranteed when each UE is individually served by one dedicated beam

Massive measurements of 5G exposure in a town: methodology and results

We target the problem of performing a large set of measurements over the territory to characterize the exposure from a 5G deployment. Since using a single Spectrum Analyzer (SA) is not practically feasible (due to the limited battery duration), in this work we adopt an integrated approach, based on the massive measurement of 5G metrics with a 5G smartphone, followed by a detailed analysis done with the SA and an ElectroMagnetic Field (EMF) meter in selected locations. Results, obtained over a real territory covered by 5G signal, reveal that 5G exposure is overall very limited for most of measurement locations, both in terms of field strength (up to 0.7 [V/m]) and as share w.r.t. other wireless technologies (typically lower than 15%). Moreover, our approach allows easily spotting measurement outliers, e.g., due to the exploitation of Dynamic Spectrum Sharing (DSS) techniques between 4G and 5G. In addition, the exposure metrics collected with the smartphone are overall a good proxy of the total exposure measured over the whole 5G channel. Moreover, the sight conditions and the distance from 5G base station play a great role in determining the level of exposure. Finally, a maximum of 130 [W] of power radiated by a 5G base station is estimated in the scenario under consideration

Measuring EMF and Throughput Before and After 5G Service Activation in a Residential Area

The deployment of 5G networks is approaching a mature phase in many countries across the world. However, little efforts have been done so far to scientifically compare ElectroMagnetic Field (EMF) exposure and traffic levels before and after the activation of 5G service over the territory. The goal of this work is to provide a sound comparative assessment of exposure and traffic, by performing repeated measurements before and after 5G provisioning service. Our solution is based on an EMF meter and a spectrum analyzer that is remotely controlled by a measurement algorithm. In this way, we dissect the contribution of each pre-5G and 5G band radiating over the territory. In addition, we employ a traffic chain to precisely characterize the achieved throughput levels. Results, derived from a set of measurements performed on a commercial deployment, reveal that the provisioning of 5G service over mid-band frequencies has a limited impact on the exposure. In parallel, the measured traffic is more than doubled when 5G is activated over mid-bands, reaching levels above 200 [Mbps]. On the other hand, the provisioning of 5G over sub-GHz bands does not introduce a substantial increase in the traffic levels. Eventually, we demonstrate that EMF exposure is impacted by the raw-land reconfiguration to host the 5G panels, which introduces changes in the sight conditions and in the power received from the main lobes