This paper proposes a novel spectrum sensing technique for the digital video broadcasting-terrestrial (DVB-T) systems, which utilizes the periodicity of pilot signals in the orthogonal frequency division multiplexing (OFDM) symbols. The proposed scheme can overcome the effect of the timing synchronization error by recorrelating the correlation values in the same sample distances. The numerical ...

In this paper we analyze the delay performance of an opportunistic multi-channel medium access control scheme and compare it to that of the corresponding single channel MAC scheme. In the opportunistic multi-channel MAC scheme, we assume that the pair of sender/receiver is able to evaluate the channel quality after a certain amount of channel sensing delay and to choose the best one for data co...

To improve low sense margin at low voltage, we propose a negatively driven sensing (NDS) scheme and to solve the problem of WL-to-BL short leakage fail, a variable bitline reference scheme with freelevel precharged bitline (FLPB) scheme is adopted. The influence of the threshold voltage offset of NMOS and PMOS transistors in a latch type sense amplifier is very important factor these days. From...

An allocation of sensing and reporting times is proposed to improve the sensing performance by scheduling them in an efficient way for cognitive radio networks with cluster-based cooperative spectrum sensing. In the conventional cooperative sensing scheme, all secondary users (SUs) detect the primary user (PU) signal to check the availability of the spectrum during a fixed sensing time slot. Th...

Spectrum sensing is the main feature of cognitive radio technology. Spectrum sensing gives an idea of detecting the presence of the primary users in a licensed spectrum. The dynamic threshold energy detection is proposed in this paper for the spectrum sensing of Cognitive Radio. The proposed dynamic energy scheme depends on the current state of the primary user. Depending on this, dynamic thres...

wireless sensor networks (wsns) have many applications in the areas of commercial, military and environmental requirements. regarding the deployment of low cost sensor nodes with restricted energy resources, these networks face a lot of security challenges. a basic approach for preparing a secure wireless communication in wsns, is to propose an efficient cryptographic key management protocol be...

The steps for modeling and control of a hydraulic rotary actuator are discussed. Our aim is to present experimental results working with a particular sensing device for angular position as a complement to pressure sensing devices. We provide the steps in experimental system identification used for modeling the system dynamics. The cascade controller designed contains an inner loop for an accura...

Energy constraint is an important issue in wireless sensor networks. This paper proposes a distributed energy optimization method for target tracking applications. Sensor nodes are clustered by maximum entropy clustering. Then, the sensing field is divided for parallel sensor deployment optimization. For each cluster, the coverage and energy metrices are calculated by grid exclusion algorithm a...

We consider the problem of localizing a robot in a known environment modeled by a simple polygon P . We assume that the robot has a map of P but is placed at an unknown location inside P . From its initial location, the robot sees a set of points called the visibility polygon V of its location. In general, sensing at a single point will not su ce to uniquely localize the robot, since the set H ...

We apply a Gaussian state formalism to track fluctuating perturbations that act on the position and momentum quadrature variables of harmonic oscillator. Following seminal proposal by Tsang Caves [Phys. Rev. Lett. 105, 123601 (2010)], Einstein-Podolsky-Rosen correlations with an ancillary oscillator are leveraged significantly improve estimates as relevant sensor can be arbitrarily squeezed whi...