The decentralized Cognitive Radio Medium Access Control (CR MAC) protocols proposed so far are usually evaluated considering homogeneous sensing conditions where all Secondary Users (SUs) share the same view of the channel. By doing so, realistic heterogeneous channel sensing conditions are neglected, which happens due to different spectrum sensing errors and/or different patterns of channel occupation by the…
Tags: OMNeT++ VANET
Automatic digital modulation recognition using minimum feature extraction
Auto modulation recognition schemes of digitally modulated signal plays a vital role in both military and civil applications like software defined radio, electronic warfare, cognitive radio systems, radio spectrum management, threat analysis and electronic surveillance. In this paper we proposed a new algorithm to distinguish between 6 digital modulation schemes (ASK-2, FSK-2, PSK-2, ASK-4, FSK-4, and PSK-4). Simulation results show that…
An energy efficient cognitive radio system with quantized soft sensing and duration analysis
In this paper, an energy efficient cognitive radio system is proposed. The proposed design optimizes the secondary user transmission power and the sensing duration combined with soft-sensing information to minimize the energy per goodbit. Due to the non-convex nature of the problem we prove its pseudo-convexity to guarantee the optimal solution. Furthermore, a quantization scheme, that discretize the…
Hand gesture recognition for automatic tap system
This paper presents a technique for real time human hand gesture recognition system for automatic tap operation. Hand gesture recognition based machines have been widely developed in recent years. Most of the techniques use skin color models due to its robustness and simplicity. In this work there are two major steps for achieving this goal:…
Gain enhancement of butler matrix fed antenna array system by using planar circular EBG units
In this paper planar circular Electromagnetic Band Gap (EBG) structures have been implemented in the Butler matrix fed antenna array system to improve the radiation performance of the system. Initially a conventional 4×4 Butler matrix fed antenna array system has been designed at 14.5 GHz. Asymmetricity in the gain values of major beams of the…
A Location-wise Predetermined Deployment for Optimizing Lifetime in Visual Sensor Networks
Visual sensor networks are receiving significant attention due to their potential applications ranging from surveillance to tracking domains. Nevertheless, due to the funneling effect, the unbalanced energy usage among visual sensor nodes (SNs) increases and leads to premature decrease in networklifetime. Firstly, considering Rayleigh fading channel and routing models, we analyze the optimization ofnetwork lifetime…
Exact Outage Analysis in Cognitive Two-Way Relay Networks With Opportunistic Relay Selection Under Primary User’s Interference
In the current study of cognitive relay networks, most related works focus on the effect of interference from secondary users (SUs) to primary receivers (PRs), while neglecting the links from primary transmitters (PTs) to SUs. In this paper, the interference both from SUs to PRs and from PTs to SUs is considered in the analysis…
Enhancement of Hybrid Cognitive Approach for Femtocells
The use of femtocells with cognitive capabilities is considered as a promising way for interference mitigation. The femto access point (FAP) accesses the spectrum either in overlay or underlay fashion. In the former case, the FAPs utilize only radio resources currently not occupied by the macrocell. In the latter case, the whole bandwidth may be…
Jamming-Resilient Secure Neighbor Discovery in Mobile Ad Hoc Networks
Secure neighbor discovery is fundamental to mobile ad hoc networks (MANETs) deployed in hostile environments and refers to the process in which two neighboring nodes exchange messages to discover and authenticate each other. It is vulnerable to the jamming attack in which the adversary intentionally transmits radio signals to prevent neighboring nodes from exchanging messages.…
Real time personalized search on social networks
Internet users are shifting from searching on traditional media to social network platforms (SNPs) to retrieve up-to-date and valuable information. SNPs have two unique characteristics: frequent content update and small world phenomenon. However, existing works are not able to support these two features simultaneously. To address this problem, we develop a general framework to enable…