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.
In this paper, highly efficient practical concatenated coding schemes with multiple short length polar codes and single-parity-check codes are proposed. As for hardware complexity, required memory space is significantly reduced by utilizing small decoding units geared to serialized decoding of short-length component polar codes. In theoretic analysis, each component short polar code shows much improved...
We consider the following variant of the index coding problem. A transmitter wishes to communicate several messages, each of which is k bit long, to multiple informed receivers over a noisy broadcast link. Each informed receiver already knows some of the messages a priori, which is called its side information, and demands to know the rest of the messages. However, unlike in an index coding problem,...
This paper deals with the recently introduced class of Non-Surjective Finite Alphabet Iterative Decoders (NS-FAIDs). First, optimization results for an extended class of regular NS-FAIDs are presented. They reveal different possible trade-offs between decoding performance and hardware implementation efficiency. To validate the promises of optimized NS-FAIDs in terms of hardware implementation benefits,...
State-of-the-art LTE Turbo-Code decoder architectures support throughputs of several Gbps by employing parallelism on different architectural levels. However, a very high flexibility with respect to code block sizes and code rates must also be retained. Sophisticated techniques are used to maintain communications performance at high code rates which are critical. In this paper, we propose new techniques...
In conventional large-scale networks, creation and management of network services are costly and complex tasks that often consume a lot of resources, including time and manpower. Network softwarization and network function virtualization have been introduced to tackle these problems, aiming at decreasing costs and complexity of implementing new services, maintaining the implemented services, and managing...
Network Function Virtualization (NFV) is considered one of the key technologies for the 5G mobile networks. In NFV, network functions are implemented in software components denominated Virtual Network Functions (VNFs) running on commodity hardware. In this paper, we propose an analytical model based on an open queuing network of G/G/m queues to model VNFs with several components, and chains of VNFs...
The exponential growth of mobile data traffic still remains an important challenge for the mobile network operators. In response, the 5G scene needs to couple fast connectivity and optimized spectrum usage with cloud networking and high processing power, optimally combined in a converged environment. In this paper, we investigate two 5G research projects; SESAME [1] and COHERENT [2]. We consider the...
We theoretically study the joint functional split selection and scheduling problem that arises in a Centralized Radio-Access-Network (C-RAN) architecture with a central location connected to a set of Remote Radio Heads (RRHs) through fronthaul links. We consider a static scenario where a set of LTE frames at the central location need to be transported to RRHs through the fronthaul topology. One frame...
With the rapid deployment of the high speed railway (HSR), the wireless communication in HSR has been one of the indispensable scenarios in the fifth generation (5G) communications. In order to improve the performance of the orthogonal frequency division multiplexing (OFDM) system in the HSR scenarios, we propose an enhanced linear minimum mean square error channel estimation scheme based on multi-path...
Ultra-reliable low-latency communications (URLLC) entail the transmission of sporadic and small packets, with low latency and very high reliability. Among many potential areas of optimization for URLLC, the problems of large delays during HARQ retransmissions, and inaccurate link adaptation as a consequence of the rapidly-varying interference conditions are studied. The former is addressed by reducing...
Billions of Machine Type Communication (MTC) devices are foreseen to be deployed in next ten years and therefore potentially open a new market for next generation wireless network. However, MTC applications have different characteristics and requirements compared with the services provided by legacy cellular networks. For instance, an MTC device sporadically requires to transmit a small data packet...
Massive Machine Communication (MMC) in the next generation of mobile communication (5G) systems requires new Medium Access Control (MAC) and physical (PHY) layer concepts to handle massive access with low overhead. The recently developed concept coded random access is capable of resolving collisions in massive access at MAC layer. Furthermore, Compressive Sensing Multi-User Detection (CS-MUD) achieves...
Nowadays, wireless sensor networks (WSNs) have become omnipresent. Also location-based services become more and more popular. In this context, energy- and location-awareness are essential properties of modern sensor networks. Addressing low-power positioning, received signal strength indicator (RSSI)-based direction finding is a prospective approach for WSNs providing location-based services. However,...
Direct position determination (DPD) determines the target localization directly from the raw observations, which is superior to traditional methods estimating related parameters firstly. However, DPD is based on maximum likelihood (ML) estimator with large data transmission and computational cost. In this paper, we develop low complexity beamspace DPD (BS-DPD), converting the raw data into beamspace...
Accurate odometry is required for robust and reliable localization of mobile wheeled robots. Therefore, odometry is combined often with a positioning system and data fusion algorithms. However, odometry parameters are not known in advance and vary depending on environment and age of the vehicle. A typically approach to solve this problem is to employ on-demand calibration. Current approaches are sensitive...
Ultra-wideband localization systems are widely known to perform with high accuracy using time-of-flight (TOF) algorithms, which are demanding in terms of tag-side power consumption. Systems optimized for power efficient tags are prone to be implemented using time-difference of arrival (TDOA) algorithms. However, due to dilution of precision and the additional required synchronization, TDOA systems...
In this paper, a passive array processing algorithm is proposed for localising the near-far field multipaths of the desired signal in the presence of co-channel interference. By expressing the unknown path delay as a function of the path's range, the proposed spatiotemporal localisation algorithm estimates the locations of all the multipath reflectors of the desired signal source using a subspace-type...
Creating an efficient localization algorithm for Internet of Things (IoT) and heterogeneous networks has been of the greatest challenges in the recent years for the researchers and industries. There has been significant efforts to increase the estimation accuracy and computational speed of localization algorithms either by improving the already existing ones or proposing new solutions. In this paper...
High precision location information formulates the basis of many modern wireless location based services (LBS). However, location privacy becomes an important issue along with the advantages that LBS offers. In this paper, we first show that, a novel eavesdropper is able to perform position estimation of the agent by purely overhearing the measurement signals between agents and anchors, using a time...
An approach for direct wireless positioning with narrowband signals is extended by multi-tone signalling allowing for dramatically increased accuracy and robustness compared to single-tone. The concept employs a multi-tone transmitter and multiple (partially synchronized) antenna arrays. The position estimates are based on pseudo-spectra algorithms like MUSIC. Multipath is mitigated with sufficiently...
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.