The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
The heterogeneous network concept in many respects meets customer requirements and maintains high energy efficiency. In this paper, we mainly investigate the impact of deployment efficiency of heterogeneous small cells BSs compared to the advantages of increasing the performance of wireless networks as a whole. We used well-known analytical models for calculating the values that can be obtained for...
The performance of massive multiple-input multiple-output (MIMO) systems is heavily affected by pilot contamination. This paper considers the problem of pilot contamination in massive MIMO systems, and investigates the normalized mean square error (NMSE) of the minimum mean square error (MMSE) channel estimation algorithm in the presence of pilot contamination. An effective uplink training strategy...
Proactive caching is a promising technology in 5G wireless networks. Small-cell base stations (SBS) can cache popular contents to assist the macro base station, and proactive caching are considered to cope with the weak backhaul links of SBSs. However, obtaining popular contents and making the optimal caching strategy may be challenging. In this paper, a novel learning-based approach is proposed,...
Human mobility pattern analysis are interesting and important topic which has become feasible nowadays by the flashing development of data collection and analysis platform technology. This paper leverages Call Detail Records(CDRs) data to analyze the mobility patterns of samples from Beijing residents. First, collective mobility and commuting patterns shows that Beijing residents are much busier than...
These days wireless sensor networks are being used in many different fields. Limited energy and efficient usage of energy are the most important factors that should be considered in these networks. Node clustering increases the efficacy of the energy consumption. Each cluster has a cluster head(CH) that is a member of that cluster and its duty is sending and receiving data in the network. So finding...
Vehicle-to-vehicle (V2V) communication technology based on Wi-Fi technology has recently been used to prevent vehicles from colliding with each other. However, in V2V communications, radio waves cannot be diffracted well enough at intersections at which vehicles cannot detect each other. Therefore, such technology might not prevent traffic accidents from occurring. In this study, we used mobile networks...
500kV substation on duty gradually tends to be unmanned with the development of smart grids, the mobile robot that used in substation equipment inspection emerge as the times require. Substation inspection robot system, which is described in this paper, can replace a fixed video monitoring, complete video remote transmission of information, equipment control, accident treatment and coordinated transport...
In this paper, the Beidou satellite navigation system based on the establishment of Beidou Positioning base station, select the cloud platform RTK forwarding mode, using ARM9 processor as the main controller, through the PID to adjust the output control signal, sending CAN communication instructions to control the hydraulic system to complete the intelligent agricultural machinery automatic control,...
In this study, the resource blocks (RB) are allocated to user equipment (UE) according to the evolutional algorithms for long term evolution (LTE) systems. Particle Swarm Optimization (PSO) algorithm is one of the evolutionary algorithms, based on the imitation of a flock of birds foraging behavior through learning and grouping the best experience. Therefore, we propose a Simple Particle Swarm Optimization...
Increasing demand in multimedia streaming has led to the advancement of Internet speed, reliability and other techniques. The 3GPP LTE network uses eMBMS protocol for broadcasting and multicasting the multimedia streaming, still the base station overloading has become an alarming issue due to the growing need of the mobile users. Since bandwidth is scares and limited, many emerging fields such as...
Providing low cost, reliable and efficient applications become the major pillars of Internet of Things. According to coverage range, Low Power Wide Area Networks (LPWAN) take a prominent place at the expense of cellular networks based applications. Based on real-life measurements, we evaluate the LoRa (Long Range) coverage within Dakar peninsula covering a ground area of 83Km2. The measurements were...
Efficient utilization of sensor energy to prolong the WSN' lifetime is proposed in this paper. A hybrid PSO Genetic sleep scheduling algorithm for WSNs to escape the local optima trap is the focus of this work. The proposed scheme uses a new parameter: Local Optimum Detector (LOD) for switching from PSO to GA algorithm in order to escape to the local optima trap caused by PSO.
In wireless network systems, time of arrival (TOA) scheme is always needed to implement the self-localization of the user manual. If multiple positions of interest exist, the Cramer-Rao lower bounds (CRLBs) of TOA localization in these positions are determined by the deployment of the base stations. The design of base station placement is addressed in this paper; and rather than the exhaustive method...
In this paper, we consider a two-tier cellular network consisting of a primary macro cell base station (PMBS) which is overlaid by cognitive small cell base stations (CSBSs) to achieve efficient spectrum utilization. The deployment of two-tier cellular networks can provide higher capacity for the system but also causes cross-tier, intra-tier, and inter-tier interference within the cellular networks...
We examine possibilities for transmit power reduction both from the relay station (R) and the base station (S − Source) on downlink in dual-hop OFDM decode-and-forward (DF) relay system. Two solutions, known for capacity enhancement in OFDM based relay systems, are applied for improving energy efficiency, while keeping end-user capacity on the same level. In the first analyzed solution, it is assumed...
This paper addresses the problem of single-cell point-to-multipoint communications. We consider a base station that needs to transmit a common information to a group of users. We propose a layered Wyner-Ziv coding (WZC) scheme based on nested lattice quantization. In our scheme, we use the base layer generated by a standard coder as the decoders side information. Then, WZC is performed for quality...
mm-Wave is a promising technology to meet the enormous bandwidth demands of the future generation cellular networks. This technology has vast amount of unused bandwidth, but has problem of human blockage. Blockage mitigation methods for indoor environments cannot be applied to outdoor scenarios effectively. In this paper, we mitigate human blockage of the mm-Wave technology by proposing an algorithm...
With the tremendous advances in the field of information and communications technology (ICT), and the emergence of new applications, such as 4K/8K, AR/VR, Internet of Things, and Industrial Internet and so on, the traditional Internet has faced severe challenges on scalability, flexibility, controllability, mobility and security and so on. In order to cope with these challenges, numerous promising...
Cellular service providers continuously upgrade their network software on base stations to introduce new service features, fix software bugs, enhance quality of experience to users, or patch security vulnerabilities. A software upgrade typically requires the network element to be taken out of service, which can potentially degrade the service to users. Thus, the new software is deployed across the...
MPEG has recently proposed Server and Network Assisted Dynamic Adaptive Streaming over HTTP (SAND-DASH) for video streaming over the Internet. In contrast to the purely client-based video streaming in which each client makes its own decision to adjust its bitrate, SAND-DASH enables a group of simultaneous clients to select their bitrates in a coordinated fashion in order to improve resource utilization...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.