September 14, 2018
Mobile networks must meet the emerging demands of services and applications with crucial latency and reliability requirements. Ultra Reliable Low Latency Communication (URLLC) is one of the key services in 5G communications with various applications such as remote control, autonomous driving, and tactile internet. In general, reliability is defined as the probability that data with a given latency is successfully delivered, and it is critical for safety in many up […]
September 9, 2018
5G networks are developed with the ambition to support a wide range of highly demanding services and application, by pushing the network capabilities to provide extreme performance, including the support of massively interconnected devices in the context of Machine Type Communication (MTC) [1]. MTC is a communication paradigm where a number of devices or ‘things’ are attached to the Internet or directly connected and communicate with each other with little […]
September 7, 2018
3GPP is the organization responsible for the specification of the 5G architecture and its operation, which is currently arrived at Release 15. [1] The entire 5G architecture can be divided into an access network (AN), composed of all the physical apparatus and logical elements needed for radio connectivity to user equipment (UE – e.g., Smartphones, IoT devices, vehicles, etc.), and the 5G core (5GC), which manages the user end-to-end connection […]
September 7, 2018
Control-/User Plane Separation (CUPS) [1] in mobile networks refer to the complete separation between control plane functions (which take care of the user connection management, as well as defining QoS policies, performing user authentication, etc.) and user plane functions (which deal with data traffic forwarding). It was first introduced by 3GPP’s Release 14 at packet data gateway level, concerning the 4G Evolved Packet Core (mobile core for 4G networks) and […]
September 6, 2018
Game theoretic approaches in wireless networks One of the fundamental questions for 5G network architectures is whether the number of base stations (BSs) will be increased (Ultra-Dense Network) or will the current BSs be enhanced with an increased number of antennas and higher processing capabilities (massive MIMO). In most studies, both of these features are investigated together. Either way, the number of antennas will be significantly increased, hence several challenges […]
September 6, 2018
The huge increase of generated data in the network it is also bringing a big increase of the metadata used to track what is happening in the network. This kind of data can be fully characterized as a big data as it is fulfilling all 4Vs of Big data, Volume, Variety, Velocity, and Variability. Once Big data is collected and stored it is necessary to process it, which for results […]
September 6, 2018
The C-RAN (Cloud, Centralized, and Co-operative Radio Access Network) architecture, firstly proposed by China Mobile in 2011 [1] will be one of the very important technologies in the 5G. In this network architecture, base station, known as eNodeB within the LTE network architecture, is disaggregated into two parts: the Radio Remote Unit (RRU) and the Base Band Unit (BBU). The separation is enabling different advantages, like the possibility of sharing […]
September 3, 2018
Ubiquitous coverage and high data rates are significant characteristics of future wireless systems. In traditional cellular systems, base-stations are located at the cell center to serve users, which are spatially distributed, across the cell. However, the dead spots within the cell caused by shadowing and penetration loss may significantly degrade the radio propagation strength of communication links, which in turn limit performance of the system. Such performance degradation is most […]
September 3, 2018
Communications over wireless medium are very appealing, because they enable mobility, however are special challenging due to the variation of the channel over the time and over frequency band. Channel is the physical medium that is used to send the signal from the transmitter to the receiver. The radio link between the transmitter and receiver may vary from the ones where transmitter and receiver are in simply line of sight […]
September 3, 2018
Mobile central office re-architected as a datacenter (M-CORD) is an open source platform enabling 5G mobile networks, which is built on software defined networking (SDN), network function virtualization (NFV) and cloud technologies. It includes virtualized Radio Access Network (RAN) and virtualized evolved packet core (vEPC) to enable mobile edge applications and services. The reference implementation of the M-CORD is based on commodity servers, white-box fabric switches, disaggregated access technologies and open source software providing virtualization […]
September 3, 2018
The unprecedented surge in data traffic experienced over the last decade has stretched the telecommunications networks to their capacity. According to Cisco’s forecast (included in the Cisco Visual Networking Index: Forecast and Methodology report), global IP traffic will have increased 127-fold from 2005 to 2021. This demand rise will even be exacerbated for wireless and mobile traffic, which is expected to account for more than 60% of the total IP […]
September 3, 2018
Radio resource management (RRM) can be seen as a bundle of network optimization functions aimed at efficiently utilizing the limited radio frequency spectrum resources and radio network infrastructure. The main functions may contain: a) radio resource allocation among macrocell and small cells; b) packets scheduling – physical resource block (PRB) allocation for maximizing the cell spectral efficiency and cell throughput; c) link adaptation – adaptive modulation and coding (AMC), and […]
September 3, 2018
Current wireless communication technologies, such as Long Term Evolution (LTE) Advanced, adopt orthogonal frequency division multiplexing (OFDM) as the waveform candidate for the air interface. However, there are some key limitations, such as high peak to average power ratio (PAPR), low spectral efficiency, and strict orthogonality requirements, which significantly inhibit the performance of OFDM. To address the drawbacks of OFDM and satisfy the requirements of future communication networks, new waveforms […]
September 3, 2018
In the current cellular architecture, illustrated in Figure 1, each base stations (BS) only have access to data symbols intended for users in its coverage area. As a result, BSs process user data independently, which result in poor service quality to users at the cell edge. This is mainly due to inter-cell interference caused by the separate processing at each BS. The heterogeneous nature of 5G and beyond systems coupled […]
August 31, 2018
Multi-access Edge Computing (MEC) relies on the combination of various cutting-edge technologies [1] such as cloud computing and virtualization, a concept deployed near the end user (UE) proximity, instead of a central location. Furthermore, utilizing network function virtualization (NFV), software defined networks (SDN) and network slicing (NS) attributes, crucial requirements such as flexibility and multitenancy support are enabled. In detail: Cloud computing is a fusion of technologies which aims to […]
August 31, 2018
Multi-access Edge Computing (MEC), or formerly known as Mobile Edge Computing, is a term given by ETSI, the European Telecommunication Standards Institute, when referring to the cloud-computing capabilities offered at the edge of the network. The term was changed in September 2017, in order “to embrace the challenges in the second phase of work and better reflect non-cellular operators’ requirements” [1]. MEC is responsible to deliver computing, storage and networking […]
August 31, 2018
The radio spectrum has become an increasingly precious and rare resource and much work has been dedicated on ways to improve the capacity of mobile communication systems without actually increasing the spectrum utilized. In this sense, multiple-input multiple-output (MIMO) provides undoubtedly the best solution. Indeed, in MIMO systems the effective available communication resources are increased in the spatial domain, by adding extra antennas at the transmitter side and, often, at […]
August 31, 2018
Precoding, also known as digital beamforming, consists in using an antenna array to transmit one or multiple spatially directive signals simultaneously. Every antenna of the transmit array emits a different signal, designed in the digital domain according to some optimization criteria. Thus, precoding is particularly desirable for spatial multiplexing, where we want to transmit a superposition of signals, each with a separate directivity (i.e., each directed to a different receiver, […]
August 30, 2018
Many internet articles deal with how to setup the training of a neural network in Python/Keras, but what if we want to create our own neural network, manually setting the weights? Alternatively, what if we want to see the output of the hidden layers of our model? This blog post will go into those topics. Neural networks are typically represented by graphs in which the input of the neuron is […]
August 30, 2018
The early stages of video delivery relied on downloading, i.e., the user saves the full video on its computer and then watches it. Content providers (CP) then realized that the user quality of experience (QoE) would be improved if the user could watch parts of the video as soon as it is available in the user equipment (UE), i.e., the video is downloaded and played at the same time (streaming). […]