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.
Wireless Nano sensor Networks (WNSNs) are enabling advanced nanotechnology applications in the medical, industrial, biomedical, military, and environmental fields. Nano-devices communicate in the Terahertz band and provide a very large transmission bit-rate at the cost of high propagation delay resulting in a short communication distance due to Terahertz band peculiarities. Thus, classical MAC protocols...
Selection of appropriate detection threshold (λ) is a very critical task in energy detection scheme based cognitive radio (CR) system. λ is mainly selected by using two principles called as constant detection rate (CDR) in which λ is calculated by taking fixed value of probability of detection (Pd) and constant false alarm rate (CFAR) in which λ is calculated by taking fixed value of probability of...
A complete Digital Front-End (DFE) processor for 60 GHz polar transmitter is presented. It avoids supply modulating, RF limiters, and AM detection circuits, compared to traditional analog-centric polar transmitter architectures. The front-end processor consists of i) a poly-phase Cascaded Integrator-Comb (CIC) filter for spectrum shaping; ii) parallel COordinate Rotation DIgital Computer (CORDICs)...
We investigate the optimal power allocation that maximizes the sum throughput in two-user interference channel under individual power constraints. The optimal power allocation depends not only on the peak power level, but also on the cross channel coefficient. The derived optimal power allocation scheme is to allocate full power to both users in the case of low peak power level. However, if the peak...
In a spectrum-sharing heterogeneous network (HetNet), low-power cells such as femtocells are deployed jointly with macrocells, thereby generating interference. To tackle this critical issue in HetNets, we advocate a new interference mitigation concept that combines uncoordinated use of both interference cancellation and interference avoidance at the receiver and transmitter sides, respectively, to...
This paper proposes QoS-constrained energy-efficiency (EE) maximization scheme in a multi-antenna wireless powered network. Specifically, considering full CSI at the users, we optimize energy transmit covariance at the power transmitter, the power allocation at the users and the time allocation for energy and information transfer. The EE optimization problem is first converted into its equivalent...
Extensive deployment of heterogeneous small cells over existing macrocell cellular networks forms the Ultra-dense Small cell Network (USN). USN has emerged as a key networking architecture in 5G wireless networks. It can improve network coverage and boost system capacity. However, the dense overlapped deployment of small cells leads to a complex interference problem. In this paper, we jointly implement...
Amendments in 802.11n have opened doors to variety of methods to stretch data rates up to 600Mbps. These include spatial diversity, spatial multiplexing both feasible due to MIMO channels, frame aggregation, block acknowledgements, smaller guard interval, channel bonding etc. This paper discusses adaptive framework using of these techniques for efficient rate adaptation of 802.11n. Rate adaptation...
Interest in ALOHA has waned because its throughput is low in comparison to other more complex MAC protocols. Yet those protocols suffer substantial performance degradation in networks with long relative propagation delay. Abramson's well accepted analysis of ALOHA estimates a maximum throughput of 18.6% assuming an infinite number of nodes and a Poisson distribution of transmitted packets. Previous...
By current medium access control mechanisms designed for Half-duplex (HD), a node in distributed In-band Full-duplex (IBFD) wireless networks cannot identify the HD or IBFD transmission modes of the other nodes. This will decrease IBFD transmission opportunities by preventing simultaneous transmission in asymmetric dual link. In this paper, we propose a novel in-band Full-duplex Distributed Medium...
The throughput of a conventional rate-compatible code based hybrid automatic repeat request (HARQ) protocol is lower-bounded by the rate of the mother code used. The mother code rate along with the highest puncture rate determine the operation range of the protocol in terms of the average received signal-to-noise ratio (SNR). In this paper, we propose a new HARQ protocol based on rate-compatible punctured...
Recently, non-orthogonal multiple access (NOMA) has gained more attention as a candidate multiple access scheme for future radio access. A major reason for this is that NOMA has the potential to achieve a more favorable tradeoff between system efficiency and user fairness than orthogonal multiple access (OMA), which is adopted in the 4th generation mobile communication systems such as LTE and LTE-Advanced...
In this paper, we propose solutions to the transmission mode selection and resource allocation problems for D2D unicast communications. We first formulate a joint mode selection and resource allocation problem, which we further decompose into separate mode selection and resource allocation problems, which are run at different timescales. Our mode selection algorithm determines the optimal transmission...
The paper investigates the problem of maximizing the expected achievable sum rate in a fading multiple access cognitive radio network when secondary user (SU) transmitters have energy harvesting capability, and perform cooperative spectrum sensing. We formulate the problem as maximization of throughput of the cognitive multiple access network over a finite time horizon subject to a time averaged interference...
In this paper we study the problem of increasing the decoding success probability of random linear fountain code over GF (2) for small packet lengths used in delay-intolerant applications such as multimedia streaming. Such code over GF (2) are attractive as they have lower decoding complexity than codes over larger field size, but suffer from high transmission redundancy. In our proposed coding scheme...
The emergence of Internet-of-Thing (IoT) has driven tremendous growth of number of connected devices such that in the near future everything is connected to the networks forming super-dense networks. To cope with this challenge, this paper investigates networks with multiple relays serving massive number of devices (users), termed as multiway multirelay (MWMR) networks. Coded random access is adopted...
In a recent work, a regular grid-based network topology with multihop relaying was investigated. A transmission strategy which maximizes the throughput while exploiting the large propagation delay was presented, and the upper bound on throughput established. However, deployments of communication nodes in the ocean inevitably result in slight positional deviations from the expected locations of the...
In this manuscript a new ARQ strategy is proposed, which is inspired by Slepian - Wolf source coding problem with side information in lossless case. Using one example based on exploitation of a Hamming code it is shown the new ARQ strategy can have a higher throughput than common ARQ method.
Energy Efficiency in wireless communication is very important due to the slow progress in battery technology with improvement in technology. In this paper, we applied energy efficient link adaptation using Machine learning techniques in Orthogonal Frequency Division Multiplexing (OFDM). We sounding the channel condition periodically and observing the channel parameters. Our aim is to select the optimal...
To study dynamic aspects of network protocols, like the transmission network protocol TCP, and networked control systems (NCS) with a UDP-like flow in a single framework, we employed UPPAAL, a tool that simulates discrete event systems as switched automata. Delays and packet losses can degrade the performance of a control loop, leading in the worst case to instability. In opposition to standard communication...
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.