Power Saving Mechanism Research Articles

Secure Triggering Frame-Based Dynamic Power Saving Mechanism against Battery Draining Attack in Wi-Fi-Enabled Sensor Networks.

Wireless local area networks (WLANs) have recently evolved into technologies featuring extremely high throughput and ultra-high reliability. As WLANs are predominantly utilized in Internet of Things (IoT) and Wi-Fi-enabled sensor applications powered by coin cell batteries, these high-efficiency, high-performance technologies often cause significant battery depletion. The introduction of the trigger frame-based uplink transmission method, designed to enhance network throughput, lacks adequate security measures, enabling attackers to manipulate trigger frames. Devices receiving such frames must respond immediately; however, if a device receives a fake trigger frame, it fails to enter sleep mode, continuously sending response signals and thereby increasing power consumption. This problem is specifically acute in next-generation devices that support multi-link operation (MLO), capable of simultaneous transmission and reception across multiple links, rendering them more susceptible to battery draining attacks than conventional single-link devices. To address this, this paper introduces a Secure Triggering Frame-Based Dynamic Power Saving Mechanism (STF-DPSM) specifically designed for multi-link environments. Experimental results indicate that even in a multi-link environment with only two links, the STF-DPSM improves energy efficiency by an average of approximately 55.69% over conventional methods and reduces delay times by an average of approximately 44.7% compared with methods that consistently utilize encryption/decryption and integrity checks.

Integrated Power-Efficient Time-Frequency Operations With DRX and BWP Switching

Bandwidth part (BWP) and discontinuous reception (DRX) are critical designs to help devices save power. Unlike DRX, a time-domain power-saving mechanism, the BWP is a frequency-domain mechanism newly proposed in the 3GPP NR system. The interaction between the two mechanisms needs investigation for performance optimization. Therefore, this work proposed a joint design for the BWP switching algorithm and analytical models. The simulation results showed that when the DRX cycle is 320 ms, and the packet arrival rate is 0.01/ms, our method improves 31.4% of packet delay or 19.5% of power consumption compared to the baselines. We also showed the range of the traffic arrival rate that a UE with both mechanisms configured is sensitive to the BWP switch strategy.

NR DCP: An Enhanced Power Saving Mechanism With Wake-Up Signal Enabled DRX

NR DCP: An Enhanced Power Saving Mechanism With Wake-Up Signal Enabled DRX

Power Saving Mechanism for Streetlight by using IoT

Abstract: There have been a predetermined number of brilliant roads in save social orders, and throughout the course of recent many years, streetlights and the executive’s guideline have been moderately basic. In any case, as the world has turned into a more prosperous local area and as urbanization has expanded, the quantity of savvy social orders in present day urban communities has expanded quickly. Consequently, it became difficult to regulate and maintain street lights in smart cities and societies. In addition, it is thought to be the first generation of the original street light control, which was inefficient and a waste of personnel. Right now, streetlights control a large part of the metropolitan climate just through manual control, by means of a control switch introduced inevery streetlight. A lot of electrical energy is lost.

High-Performance and Power-Saving Mechanism for Page Activations Based on Full Independent DRAM Sub-Arrays in Multi-Core Systems

High-Performance and Power-Saving Mechanism for Page Activations Based on Full Independent DRAM Sub-Arrays in Multi-Core Systems

An Enhancement for IEEE 802.11 STA Power Saving and Access Point Memory Management Mechanism

Wi-Fi researchers are trying hard to extend battery life by optimizing 802.11 power save. The rising number of Wi-Fi devices and IoT devices and daily demands have reduced Station (STA) device power consumption. Better memory management at the Access Point (AP) side is also needed, so that AP can store maximum data to deliver sleepy STA devices. There are three main contributions of this study. The first one focuses on a power-saving mechanism scheme with an adaptive change to Listen Interval (LI) based on the battery status of station devices. The second contribution aims to examine better memory management for the AP buffer to store packets that will in the future deliver power-saving STA when awake. The third contribution, under the implementation of the proposed method, includes Wi-Fi corner cases covered as Beacon frames missed via STA, the keep-alive factor, and the upper-layer time taken to care for and ensure the delivery of unicast/multicast/broadcast data. The proposed approach introduced 802.11 protocols to share battery status, a protocol to announce proposed features via AP, and a protocol to change LI at runtime. Simulation results show that the proposed scheme performs better than 802.11 power saving in terms of power usage at the STA and access point memory management.

Analysis of Non-Steady Queue-Length Distribution in a Finite-Buffer Model with Group Arrivals and Power Saving Mechanism with Setups

In the manuscript, a probability distribution of the queue length is studied in a model with group Markov arrivals, arbitrarily distributed service times and finite waiting room. After the period of suspension of service due to lack of packets, each new busy period is preceded by a random setup time. Integral equations for time-dependent queue-length distribution are derived by identifying renewal moments in the operation of the system and by applying total probability law. The representation for the solution of the system is found in terms of Laplace transforms. Computational examples illustrating the impact of system parameters on the queue-length distribution are included.

Queue-Size Distribution in a Discrete-Time Finite-Capacity Model with a Single Vacation Mechanism

In the paper a finite-capacity discrete-time queueing system with geometric interarrival times and generally distributed processing times is studied. Every time when the service station becomes idle it goes for a vacation of random duration that can be treated as a power-saving mechanism. Application of a single vacation policy is one way for the system to achieve symmetry in terms of system operating costs. A system of differential equations for the transient conditional queue-size distribution is established. The solution of the corresponding system written for double probability generating functions is found using the analytical method based on a linear algebraic approach. Moreover, the representation for the probability-generating function of the stationary queue-size distribution is obtained. Numerical study illustrating theoretical results is attached as well.

A Segmented Adaptive Router for Near Energy-Proportional Networks-on-Chip

A Network-on-Chip (NoC) is an essential component of a chip multiprocessor (CMP) which however contributes to a large fraction of system energy. The unpredictability of traffic across a NoC frequently involves an expensive over-sizing of NoC resources which in turn leads to a significant contribution to the CMP power consumption. There exists a body of work addressing this issue, however so far solutions fall short when aiming for power reduction whilst maintaining high NoC performance. This paper proposes to combine router architecture optimizations with smart resource management to overcome this limitation. Based on a fully segmented architecture, we present an online adaptive router adjusting its active routing resources to meet the current traffic demand. This enhanced power-gating strategy significantly decreases both static and dynamic power consumption of the NoC, up to 70% for synthetic traffic patterns and up to 58% for real traffic workloads, while preserving NoC latency and throughput. Thanks to these adaptive power-saving mechanisms the proposed segmented NoC router provides near energy-proportional operation across the range of used benchmarks.

Persistent Periodic Uplink Scheduling Algorithm for Massive NB-IoT Devices.

Narrowband Internet of Things (NB-IoT) is one of the low-power wide-area network (LPWAN) technologies that aim to support enormous connections, featuring wide-area coverage, low power consumption, and low costs. NB-IoT could serve a massive number of IoT devices, but with very limited radio resources. Therefore, how to enable a massive number of IoT devices to transmit messages periodically, and with low latency, according to transmission requirements, has become the most crucial issue of NB-IoT. Moreover, IoT devices are designed to minimize power consumption so that the device battery can last for a long time. Similarly, the NB-IoT system must configure different power-saving mechanisms for different types of devices to prolong their battery lives. In this study, we propose a persistent periodic uplink scheduling algorithm (PPUSA) to assist a plethora of Internet of Things (IoT) devices in reporting their sensing data based on their sensing characteristics. PPUSA explicitly considers the power-saving mode and connection suspend/resume procedures to reduce the IoT device’s power consumption and processing overhead. PPUSA allocates uplink resource units to IoT devices systematically so that it can support the periodic–uplink transmission of a plethora of IoT devices while maintaining low transmission latency for bursty data. The simulation results show that PPUSA can support up to 600,000 IoT devices when the NB-IoT uplink utilization is 80%. In addition, it takes only one millisecond for the transmission of the bursty messages.

AM Mini-LED Backlight Driving Circuit Using PWM Method With Power-Saving Mechanism

This paper proposes a mini-light-emitting diode (mini-LED) driving circuit that is driven by pulse width modulation (PWM) for the backlights of active-matrix (AM) liquid crystal displays (LCDs). The proposed circuit compensates for threshold voltage (V_TH) variations of low-temperature poly-crystalline silicon thin-film transistors (LTPS TFTs) and the current-resistance (I-R) rise in VSS lines to supply a stable driving current. Operating the mini-LED at the high luminous efficacy by the PWM driving method and setting only the driving TFT on the path of the driving current reduce the power consumption of the backlight. Based on a 2.89-inch LCD panel with an AMLED <inline-formula> <tex-math notation="LaTeX">$48\times48$ </tex-math></inline-formula> backlit module, the TFTs are fabricated, measured, and fitted. Simulation results show that the relative current error rates are all below 4.67&#x0025; when the V_TH of the driving TFT varies by &#x00B1;0.3 V and the VSS rises by 0.5 V. The voltage across VDD and VSS of the proposed circuit is 4.5 V lower than that of the 6T1C compensating driving circuit, so the power consumption of the circuit is at least 27.05&#x0025; lower. Therefore, the proposed driving circuit is well suitable to use in mini-LED backlit LCDs.

On the Time to Buffer Overflow in a Queueing Model with a General Independent Input Stream and Power-Saving Mechanism Based on Working Vacations.

A single server queue with a limited buffer and an energy-saving mechanism based on a single working vacation policy is analyzed. The general independent input stream and exponential service times are considered. When the queue is empty after a service completion epoch, the server lowers the service speed for a random amount of time following an exponential distribution. Packets that arrive while the buffer is saturated are rejected. The analysis is focused on the duration of the time period with no packet losses. A system of equations for the transient time to the first buffer overflow cumulative distribution functions conditioned by the initial state and working mode of the service unit is stated using the idea of an embedded Markov chain and the continuous version of the law of total probability. The explicit representation for the Laplace transform of considered characteristics is found using a linear algebra-based approach. The results are illustrated using numerical examples, and the impact of the key parameters of the model is investigated.

LED Lighting Circuit Design with Automatic Light Supplement

This article mainly develops white LED lighting with automatic light supplement. It is hoped that the circuit can judge the strength of the external light source to automatically control whether the lamp is on or not, so as to reduce the consumption of excess energy and save considerable energy over time. We use a photo resistor element to sense the change in the intensity of the external light source, and then use an operational amplifier as a comparator to compare the voltage rise and fall of the photo resistor due to light, so that the circuit can distinguish when to use the brighter mechanism, a more power-saving mechanism and when to use it. Finally, a white LED lighting system with automatic fill light was built to verify the theory and method of this article.

How Much Benefit Can Dynamic Frequency Scaling Bring to WiFi?

Dynamic frequency scaling (DFS) is a state-of-the-art power-saving technique. Various DFS-based WiFi schemes have been proposed for power saving. These schemes demonstrated the power-saving feasibility of DFS via hardware implementation or simulation. This paper is the first that proposes a general theoretical framework to evaluate the performance of these schemes, where we use Queuing theory to analyze the system throughput and use Semi-Markov theory to quantify the power consumption. In addition, we adopt the energy efficiency (i.e., the throughput per energy cost) to compare the gains of these schemes. This efficiency measure can be used to make a trade-off between system throughput and power consumption and therefore help us choose appropriate parameter settings. Extensive simulations verify that our theoretical model is very accurate and our theoretical results well match with universal software radio peripheral (USRP) experiment results. Our study shows that DFS can greatly improve the energy efficiency of WiFi networks even under low SNR conditions; for example, when SNR = 9.7 dB (i.e., the basic requirement for decoding packets in WiFi), the improvement is around 25 percent for 802.11b at rate 11 Mb/s and 16 percent for 802.11 ac at rate 1300 Mb/s. Our study also shows that DFS can be well integrated with other commonly used power-saving mechanisms to improve energy efficiency further.

An Adaptive CPU-GPU Governing Framework for Mobile Games on big.LITTLE Architectures

Games have been one of the most popular applications on smartphones. In order to meet the increasing computational complexity of mobile games, smartphones are now equipped with heterogeneous CPU multi-core architectures like big.LITTLE as well as high-performance GPUs. However, the integrated CPUs and GPUs drain the battery quickly, which has become a bottleneck for improving user experience. In addition to traditional Dynamic Voltage and Frequency Scaling (DVFS) technique for CPUs and GPUs power reduction, heterogeneous multi-core processors, such as the big.LITTLE architecture, have been designed to offer more opportunity for performance-energy tradeoffs. But current processor governors in smartphones can not exploit these power-saving mechanisms wisely, causing considerable energy waste. In this article, we propose a CPU-GPU governing framework that recognizes the performance demand for different game scenes, and select the most energy-efficient hardware configuration for the corresponding scenes. We implement our framework on an ODROID-XU4 mobile platform, and the experiments show that our framework can achieve 26.7, 16.6, and 10.5 percent power saving on average without compromising user experience when compared to the default governor used in our platform and two governors proposed by other researchers, respectively.

Wake-up Radio-Based 5G Mobile Access: Methods, Benefits, and Challenges

Future mobile networks will enable new use cases, requiring further enhanced data rates, latency, coverage, capacity, and reliability. In this article, to emphasize sustainable energy consumption and improved device battery lifetime, the concept, benefits, and challenges of utilizing wake-up radio-based access in 5G networks are reviewed and discussed. To this end, the operating principle and associated wake-up signal structures are first reviewed, together with the corresponding power consumption and buffering delay trade-offs. Then the applicability of wake-up methods at mmWave bands and beamforming systems is addressed and highlighted. Additionally, an energy-efficient mobility management procedure for wake-up radio-based devices is described and demonstrated, utilizing narrowband uplink reference signals. Overall, the article provides an overview of wake-up-based access in 5G systems as a promising power-saving mechanism, and discusses the associated prospects, benefits, and challenges.

Battery Draining Attack and Defense against Power Saving Wireless LAN Devices.

Wi-Fi technology connects sensor-based things that operate with small batteries, and allows them to access the Internet from anywhere at any time and perform networking. It has become a critical element in many areas of daily life and industry, including smart homes, smart factories, smart grids, and smart cities. The Wi-Fi-based Internet of things is gradually expanding its range of uses from new industries to areas that are intimately connected to people’s lives, safety, and property. Wi-Fi technology has undergone a 20-year standardization process and continues to evolve to improve transmission speeds and service quality. Simultaneously, it has also been strengthening power-saving technology and security technology to improve energy efficiency and security while maintaining backward compatibility with past standards. This study analyzed the security vulnerabilities of the Wi-Fi power-saving mechanism used in smart devices and experimentally proved the feasibility of a battery draining attack (BDA) on commercial smartphones. The results of the experiment showed that when a battery draining attack was performed on power-saving Wi-Fi, 14 times the amount of energy was consumed compared with when a battery draining attack was not performed. This study analyzed the security vulnerabilities of the power-saving mechanism and discusses countermeasures.

Transient Analysis of an M/M/1 Queueing System Subjected to Multiple Differentiated Vacations, Impatient Customers and a Waiting Server with Application to IEEE 802.16E Power Saving Mechanism

An M/M/1 queueing system subjected to multiple differentiated vacations, customer impatience and a waiting server is analyzed. The explicit transient probabilities of system size are derived using probability generating function technique, Laplace transform, continued fractions and some properties of confluent hypergeometric function. Further, the time-dependent mean and variance are obtained as the performance measures. A numerical example is presented in order to study the behavior of the system.

Expectation Maximization Based Power-Saving Method in Wi-Fi Direct

Wi-Fi Direct has been proposed with the purpose of enabling the connection between any two devices without requiring a wireless access point. Because of the limited battery capacity of mobile devices, it is important issue to provide an efficient energy consumption to the Wi-Fi Direct device. In order to reduce unnecessary energy consumed, Wi-Fi Direct standard defines two power-saving mechanisms: the opportunistic power-saving (OppPS) mode and notice of absence power-saving (NoAPS) mode. In this study, we propose a method to enhance the efficiency of the NoAPS mode for the transmission of multimedia video traffic. The proposed method dynamically determines the length of the awake interval long enough to guarantee the successful reception of the frame in clients with the given outage probability based on the pdf of the video frame size estimated. The shape and scale parameters of the pdf of the video frame size and the weights of all the mixture components are updated by the Expectation Maximization (EM) algorithm whenever a frame is transmitted. Furthermore, we suggest priority-based frame transmission strategy considering the inter-dependency between video frames to reduce the packet loss rate. Results show that the proposed method reduces the energy consumption and the transmission delay of Wi-Fi Direct devices compared to the existing NoAPS method.

Performance Analysis and Adaptive DRX Scheme for Dual Connectivity

The 3GPP (Rel.12 and Rel.16) introduces and explores the dual connectivity (DC). It is one of the most important future technologies adopted by 5G. It enhances the throughput and mobility robustness by enabling simultaneous dual connections with macro and small-cell evolved NodeBs (eNBs). While aggregating spectrum with the dual connections, DC induces two power-saving mechanisms of discontinuous reception (DRX). This results into offset synchronizations that decrease the feasibility of saving power. Therefore, the conventional DRX mechanism is not suitable for DC. Hence, we have proposed a synchronized adaptive DRX sleep (SAS) scheme for DRX that synchronizes its short-/long-sleep durations to make it suitable for active and background traffic. Next, we have evaluated the performance of SAS scheme with semi-Markov model in terms of DRX sleep time ratio and average delays. Moreover, in-depth analytical and simulation analyses of the DRX performance with DC have also been conducted. The accuracy of our model has been verified on the basis of a wide range of parameters. The proposed SAS scheme performs more effectively than the conventional DRX scheme for DC under different traffic types.