In this paper, an access scheme for cognitive radio networks is proposed in which secondary users (SUs) make use of the primary user(s) (PUs) channel quality feedback information. SUs decide their transmission strategy based on the PUs' channel quality indicator (CQI) feedback available in the PU network and the SUs' sensing of PUs' activity. We consider two energy sensing approaches, namely, hard

We investigate a cognitive radio network in which a primary user (PU) may cooperate with a cognitive radio user (i.e., a secondary user (SU)) for transmissions of its data packets. The PU is assumed to be a buffered node operating in a time-slotted fashion where the time is partitioned into equal-length slots. We develop two schemes which involve cooperation between primary and secondary users. To

Centralized coded caching and delivery is studied for a partially-connected fog radio access network (F-RAN), whereby a set of H edge nodes (ENs) (without caches), connected to a cloud server via orthogonal fronthaul links, serve K users over the wireless edge. The cloud server is assumed to hold a library of N files, each of size F bits; and each user, equipped with a cache of size MF bits, is

In this paper, we characterize optimal resource allocation for the uplink and downlink of wireless powered cellular networks (WPCNs). In particular, we investigate a time-slotted WPCN, where a hybrid access point (HAP) is in charge of energy replenishing of M cellular users (CUs), along with transmission/reception of information to/from them. Unlike prior works, which give attention to information

This paper characterizes the performance of a generic K-tier cache-aided heterogeneous network (CHN), in which the base stations (BSS) across tiers differ in terms of their spatial densities, transmission powers, pathloss exponents, activity probabilities conditioned on the serving link and placement caching strategies. We consider that each user connects to the BS which maximizes its average

In this letter, we show that Huffman's source coding method is not optimal for cache-aided networks. To that end, we propose an optimal algorithm for the cache-aided source coding problem. We define cache-aided entropy, which represents a lower bound on the average number of transmitted bits for cached-aided networks. A sub-optimal low-complexity cache-aided coding algorithm is presented. In

Cooperative device-to-device (D2D) communication is proposed as a promising technology to improve the spectral efficiency in crowded communication networks. In this paper, we consider a transmitter-receiver pair, operating in the D2D transmission mode, overlaying the cellular network. The D2D transmitter (DT) acts as a relay for the undelivered packets of cellular user equipment (CUE). We consider

Internet of Things (IoT) is considered as a trend nowadays. Devices connected to the internet interact with surrounding; this poses strong challenges in handling big data with a certain level of security. In this paper IoT devices will be divided in to two categories high vulnerability devices and low vulnerability devices. The classification depends on the ease of attacks. In order to ensure the

The tests and calculation of the key performance metrics of supercapacitors including capacitance, power and energy stored are commonly reported by the academia and the industry based on formulæ valid only for ideal capacitors. This is inconsistent with the fact that supercapacitors exhibit electrical behaviors that are different from those of ideal capacitors whether they are looked at in the

In this paper, a Static Noise Margin (SNM) analysis for 2T2M RRAM cell is investigated. The proposed analysis is done using mathematical formulation and verified by SPICE simulations. The analysis is tested for both, write and read modes. Moreover, the analysis is applied to diverse types of RRAM cells, and a comparison between the performance of such cells is discussed. Additionally, the effect