Stochastic modeling for energy efficiency in modified directional discontinuous reception for LTE-5G networks

Fifth-generation (5G) networks deal with high-frequency data rates, ultra-low latency, more reliability, massive network capacity, more availability, and a more uniform user experience. To validate the high-frequency rates, 5G networks engage beam searching operation. By adopting a beam searching state between the short and long sleep, one can reduce the system's delay. The energy consumption of user equipment (UE) in 5G networks is much higher than in the 4G networks. To reduce the energy consumption and increase the energy saving in UE, Long-Term Evolution (LTE)-5G networks adopt the discontinuous reception (DRX) scheme with a fixed number of short sleep. LTE-DRX without beam search operation (i.e., beam alignment) cannot work in 5G networks. Hence, keeping this scenario in mind, we have modeled a new modified directional discontinuous reception (MD-DRX) mechanism for LTE-5G networks. The MD-DRX mechanism captures the behavior of a beam searching, an inactive, an active, a long sleep, an ON, and a short sleep states. The short sleep state consists of a maximum $M$ short sleep. To get the optimal energy saving and energy consumption (i.e., energy efficiency) from the MD-DRX mechanism, it is required to check the system's throughput. The trade-off between energy saving/energy consumption and throughput will provide the system's optimal energy saving and optimal energy consumption. In this paper, we have obtained the system's optimal energy saving and throughput by optimizing the maximum short sleep and short sleep duration. To get the energy efficiency for LTE-5G networks, the trade-off between average energy consumption/energy saving and throughput is shown.     

多网融合中WLAN发现机制的能耗分析

研究3GPP(third generation partnership project)蜂窝网络与WLAN(wireless local area network)融合的无线异构网络中WLAN发现机制的能耗问题,提出一种终端能耗分析模型,分析了基于寻呼的WLAN发现机制以及其他4种WLAN发现机制的能耗.理论分析和仿真结果表明:基于寻呼的WLAN发现机制能耗最小,终端始终处于扫描状态的机制能耗最大.结果还表明:终端仅在与WLAN重叠的蜂窝小区内进行周期扫描的机制,与终端在所有的区域中进行周期扫描的机制比较,二者能耗相当.     

基于多元线性回归算法的5G基站能耗模型

5G基站能耗高,对运营商的网络运营成本带来较大的压力。优化了5G基站能耗测试方法和业务加载方法,获取了大量现网5G基站能耗和无线利用率关系的实测基础数据。基于多元线性回归算法,构建了不同场景下的5G基站能耗模型,能耗模型拟合优度达到0.99以上。     

Delay analysis for multidimensional queueing processes in CSMA/CD local area networks

A CSMA/CD local area network consists of a single server (the channel) and multiple interacting queues of message packets. The message queueing process in a buffered,p-persistent CSMA/CD system is modeled as a multidimensional semi-Markov chain. An effective approximation method to compute the mean packet delay in equilibrium is developed, based on an exact joint probability generating function of the queue length vector at embedded Markov epochs. We also develop a simulation model to validate approximation results. To the best of our knowledge, this work is the first in the literature that enables optimization of the control parameterp for the CSMA/CD system with more than two users.     

On the M/G/1 queueing system with multiclass customers and fixed feedback

The M/G/1 queueing system with multiclass customer arrivals, fixed feedback, and first come first served policy is considered, where different classes of customers have different arrival rates, service-time distributions, and feedback numbers. The joint probabifity generation function of queue size of each class and the Laplace-Stieltjes transform of the total sojourn time of a customer in each class are presented, which extended the results obtained by Choi B D. The mean queue size of each class and mean total sojourn time of a customer in each class are obtained with this result. The results can be used in computer and communication networks for their performance analysis.     

Rate allocation strategies for energy-efficient multipath routing in Ad-hoc networks towards B3G

Wireless mobile Ad-hoc network is a special network that all nodes can self-organize and work together. It is flexible to form a network and extend the coverage area dynamically without infrastructure, so Ad-hoc network is envisioned as cornerstones of future generation networking technologies (B3G or 4G). However, the dynamic network topology makes the communication cost not only the energy of source/destination nodes, but also the relay nodes. Another problem of the Ad-hoc network is it is hard to provide a stable and persistent quality of service (QoS), which is strongly required by the beyond 3rd generation (B3G) system. In this article, the authors establish a scenario that contains B3G cellular base station and Ad-hoc mobile nodes, and propose two algorithms minimum incremental rate algorithm and power feed-back rate allocation algorithm in multipath routing. The algorithms can maintain a constant total transmission rate and bit error ratio (BER) to provide the QoS guarantee and reach the minimum power consumption of the relay nodes by adjusting the rate of each path in the multipath routing.     

基于M/G/1/K排队模型的IEEE802.11e EDCA性能研究

该文利用二维Markov链分析方法,提出了一种新的IEEE802.11e EDCA网络分析模型,该模型引入了空闲状态和不同接入等级的仲裁帧间隔(AIFS)的使用;利用Markov链状态转移图的Z域信号传递函数推导了MAC层平均服务时间的概率分布;结合M/G/1/K排队模型分析了增强分布式信道接入(EDCA)在非饱和和饱和负载下的性能。经过访真实验结果与数值分析结果的对比,验证了分析模型的准确性。分析结果表明:EDCA接入机制只为不同优先级业务提供QoS区分;不同优先级业务信道接入的不公平性是EDCA接入机制的特点。     

Enhancing energy-efficient sleep scheduling for Narrowband Internet of Things devices in coordinated 5G networks within smart environments

This research project takes on a crucial role in the quickly changing field of integrated 5G networks inside smart environments by concentrating on the creation of an extremely effective sleep scheduling system designed especially for Narrowband Internet of Things (NB-IoT) devices. This work introduces a unique method for precisely controlling the nodes' sleep schedules through the use of convolutional neural network (CNN) architecture, which optimizes both energy usage and operating patterns. The principal goal still stands to guarantee the extended lifetime of operation and dependability of NB-IoT devices in the larger framework of intelligent ecosystems driven by synchronized 5G networks. To achieve its objectives, the research explores a number of complex domains and employs cutting-edge technologies and techniques, such as CNN-based pattern recognition. This method's real-time component is essential since it allows for prompt modifications to sleep schedules in order to optimize energy savings. Further boosting the devices' effectiveness and flexibility is continuous contact with a central server, which guarantees that the devices are updated with the most recent data and instructions. Essentially, the main objective of this study is to greatly increase the energy economy and operational lifetime of NB-IoT devices, which will allow for stable and long-lasting IoT deployments in the context of 5G networks in intelligent settings. This advancement is not only a boon for businesses and industries leveraging IoT technology but also a substantial step toward building smarter, more energy-efficient, and resilient smart ecosystems that benefit society as a whole.     

农村2G/4G网络分析系统的设计与应用

中国已迈入了移动互联的新时代,目前各大运营商之间激烈的竞争聚焦在了4G网络的农村市场上。因此,研发一套农村2G/4G网络分析系统软件,有助于在山区农村复杂的无线环境中实现4G信号精准覆盖,具有一定的市场与实用价值。     

Performance Investigation of IEEE 802.11e EDCA Under Non-Saturation Condition Based on the M/G/1/K Model

The IEEE 802.11e network provides different with QoS （Quality of service） guarantee for different traffic streams. The Enhanced distributed channel access （EDCA） in IEEE 802.11e MAC protocol is proposed to support prioritized QoS on the basis of the Distributed coordination function （DCF） in IEEE 802.11. We first build a new Markov chain model for the EDCA. The model takes into account both the idle state that represents that there are no packets to be transmitted and differentiation based on different AIFS-value （Arbitration inter-frame space） for different traffic. We can use the signal transfer function of the generalized Z-transform domain state transition diagram to derive a probability distribution of the MAC layer service time and analyze the performance of EDCA from a non-saturated channel to a saturated medium by using M/G/1/K queuing model. The proposed model is calculated numerically and validated against simulation results, we observed a good match between the analytical model and simulation. Simulation and theoretical results show that despite providing prloritized QoS, the EDCA still can not support strict QoS for real-time application. On the other hand, it is inevitable that there is unfairness of channel access to prloritized traffic due to EDCA.     

载噪比直接法测量地球站G/T值的精度研究

本文阐述了利用卫星信标或未调制的测试载波直接测量地球站G T值的原理和方法。研究了其测量精度 ,给出了载噪比修正的实验研究曲线 ,且对G T值的测量误差进行了分析和估计。分析结果表明 :G T值测量的均方根误差为± 0 55dB。最后 ,给出了利用载噪比直接法测量地球站G T值的实例 ,且同间接法测量结果进行了比较 ,二者吻合很好。     

Flexible and efficient hardware platform and architectures for waveform design and proof-of-concept in the context of 5G

Several technical contributions are emerging nowadays to fulfill the new requirements foreseen in the 5th generation (5G) of mobile communication systems. Among these contributions, different variants of waveform design are proposed for the new radio air interface as alternative to orthogonal frequency-division multiplexing (OFDM) adopted in 4G. However, in order to prove the feasibility and the benefits of the proposed waveforms, practical hardware implementations are necessary. This paper presents one of the first flexible and efficient hardware platforms for waveform design and proof-of-concept. The proposed platform constitutes a complete hardware/software development environment, with digital processing, radio frequency boards, and all associated interfaces for control, communication, and display. Furthermore, the proposed platform allows the support of several communication scenarios as foreseen in 5G. Promising waveform candidates are implemented, in addition to OFDM, with careful architectural choices to allow fair comparisons. Particularly, this paper presents novel hardware architectures for the UF-OFDM transmitter and receiver.     

Two‐sided matching framework for optimal user association in 5G multi‐RAT UDNs

Recently, academic and industrial research communities are paying more explicit attention to the 5G multiple radio access technology ultra‐dense networks (5G multi‐RAT UDNs) for boosting network capacity, especially in UD urban zones. To this aim, in this paper, we intend to tackle the user association problem in 5G multi‐RAT UDNs. By considering the decoupled uplink/downlink access (DUDA), we divide our user association problem into two distinct subproblems representing, respectively, the uplink and the downlink channels. Next, we formulated each one as a nonlinear optimization problem with binary variables. Then, to solve them, we were restricted by the hard complexity, as well as the hard feasibility of centralized user association schemes. Thus, to resolve our user association problem in a reasonable time and distributed manner, we formulated each subproblem as a many‐to‐one matching game based on matching theory. Next, we provide two fully distributed association algorithms to compute the uplink and downlink stable matching among user equipments (UEs) and base stations (BSs). Simulation results corroborate our theoretical model and show the effectiveness and improvement of our achieved results in terms of the overall network performance, quality of service (QoS), and energy efficiency (EE) of UEs.