Tags: mixim omnet

Wide spread of Internet of Things (IoTs) still have huddles in cost and maintenance. Energy harvesting is a promising option to mitigate battery replacement, but the current energy harvesting methods still rely on batteries or equivalent and power converters for the maximum power point tracking (MPPT). Unfortunately, batteries are subject to wear and tear, which…

Internet of Things (IoT) systems process and respond to multiple (external) events, while performing computations for a Sense-Compute-Control (SCC) or a Sense-Only (SO) goal. Given the limitations of the interconnected resource-constrained devices, the execution environment can be based on an appropriate operating system for the IoT. The development effort can be reduced, when applications are built…

Spectrum sensing is a fundamental component of cognitive radio (CR). How to promptly sense the presence of primary users (PUs) is a key issue to a CR network. The time requirement is critical in that violating it will cause harmful interference to the PU, leading to a system-wide failure. The motivation of this paper is to provide an effective…

In the field of radar sensing, a paradigm shift is taking place from the traditional radar system to distributed sensing/radar networks. Comparing with the single radar system distributed radar networkshave a superior performance in detection and estimation of parameters of target. They also enhance the imaging and classification performance of sensing systems. As in distributed radar networks several radars…

An underlay cognitive multisource multirelay cooperative network is proposed and an analytical framework to evaluate the system performance is formulated. Under both maximum transmission power and interference power constraints, exact and asymptotic outage probabilities for proactive decode-and-forward relaying over Rayleigh fading channels are derived. Both multiuser diversity and cooperative diversity can be achieved with direct secondary links.

Multiple Self-Organizing Networks (SON) functions have been deveoped towards the SON promise of automating cellular network operations. Meanwhile, advancing SON towards Cognitive CellularNetworks requires the (SON) Functions (SFs) to autonomously learn the required optimal configurations. Since the SFs adjust the same or related network parameters, conflicts are bound to occur. Mechanisms that are better than current SON coordination approaches must thus be devised to…

Based on orthogonal frequency division multiplexing (OFDM) systems, an additional individual data transmission can be established in statistical spectrum domain, which can be adopted for specific applications. However, the performance of existing detection methods for this kind of transmission will be severely restricted when the channel coefficients are dynamic within each observation window. In this…

In cognitive ratio (CR), spectrum sensing is a crucial technique aiming at exploiting spectrum white spaces. This sensing task is more difficult for multiple channels in wide bands. In this paper, we investigate spectrum sensing tasks for long-term evolution (LTE) networks in large frequency-bands. We propose an effective spectrum sensing scheme to detect LTE signals and classify the cell-identities…

Interference is one of the most limiting factors when trying to achieve high spectral efficiency in the deployment of heterogeneous networks (HNs). In this paper, the HN is modeled as a layer of closed-access LTE femtocells (FCs) overlaid upon an LTE radio access network. Within the context of dynamic learning games, this work proposes a novel heterogeneous multiobjective fully distributed…

In this paper, an energy-efficient scheme is proposed for cooperative spectrum sensing in cognitivesensor networks. In our scheme, we introduce a technique to select the sensing nodes and to set energy detection threshold so that energy saving can be accomplished in the nodes. Our objective is to minimize the energy consumed in distributed sensing subject to constraints…