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In order to meet various requirements of the 5th generation (5G) communication system, larger amounts of spectrum are required. Television White Space (TVWS) and Licensed-Assisted Access (LAA) can only utilize the specific frequency band as shared frequency and have no mechanism for sharing the other frequency bands to obtain more frequency resources. We have proposed a dynamic frequency-sharing system...
Quorum sensing (QS) is a bacterium-to-bacterium communication mechanism that uses signaling molecules called autoinducers (AI). However, such mechanism is not well defined yet due to its inherent complexity and energy constraints. We construct a communication network with the QS mechanism and analyze the average uplink channel capacity and bit-error-rate performance of the proposed system model over...
In this paper we consider the broadband-narrowband coexistence scenario where the unused spectral gaps in the professional mobile radio (PMR) frequency band are used for broadband data communications. Spectrally confined filter bank based multicarrier (FBMC) waveform is applied for broadband transmission in order to minimize the interference leakage between the new broadband system and the legacy...
Considering a small-scale fading environment in a dense random wireless network, we investigate the impact of the carrier-sensing threshold on the link performance under the premise of a fixed carrier-sensing range. At first, we assume a close transmitter-receiver distance and model the network nodes as a homogeneous Poisson point process (PPP). Then we present a simple analysis model of the conditional...
Imaging with random sensing functions may afford novel measurement geometries that circumvent constraints of conventional point-by-point imaging architectures. Here we demonstrate imaging of axial reflectivity profiles using random temporal-spatial encoding created by modal interference in a multimode fiber.
We consider the scheduling problem for Aggregated ConvergeCast in wireless sensor networks with a physical interference model. Previous work consists of either heuristics without performance guarantees, or approximation algorithms which do not perform well in practice. We propose here a first scalable mathematical SINR (Signal to Interference plus Noise Ratio) model that outputs an optimal Aggregated...
A fault can occur any time during mobile robots operation and this may cause human injuries. To ensure the safety and the reliability of mobile robots, fault detection and identification (FDI) are necessary to be addressed. The faults in this study are defined as situations that the mobile robots collide with obstacles or the obstacle interferes mobile robot motion immediately. The objectives of this...
In this paper, we investigate the impact of the carrier-sensing range on the link performance in a dense wireless network. Considering small-scale fading effects, we fix the carrier-sensing threshold and adaptively adjust the carrier-sensing range. At first, we assume a close transmitter-receiver distance and model the network nodes as a homogeneous Poisson point process (PPP). Then we obtain the...
Cognitive radio network (CRN) is regarded as an emerging technology for better spectrum efficiency where unlicensed secondary users (SUs) sense RF spectrum to find idle channels and access them opportunistically without causing any harmful interference to licensed primary users (PUs). However, RF spectrum sensing and sharing along with reconfigurable capabilities of SUs bring severe security vulnerabilities...
Radio-on-demand wireless sensor networks (WSN) are expected to be expanded the lifetime of sensor nodes because the receiver effectively utilizes the sleep/wake-up control function. The multi-carrier code division multiple access (MC-CDMA) using modified pseudo orthogonal M-sequence sets (MPOMS) codes have been proposed for radio-on-demand WSN systems. In this paper, the rigorous communication success...
The paper proposes a customized frequency domain energy detection spectrum sensing scheme. It is needed to fulfill requirements provided by the IEEE 802.22 standard, aimed at extending Internet services to Television White Space frequencies. It provides a detection scheme allowing to achieve strict sensitivity required by the protocol either in sensing time or in detection capabilities. In particular,...
In most industrial processes transfer of data and software from or to sensors is an essential part of the monitoring and control systems. Many of the older, wired communication systems have been or are being replaced with wireless alternatives. A number of challenges are associated with this replacement: Radio receivers are subject to interference from other radio sources. Similarly, radio transmitters...
Internet of Things (loT) aims at collecting data from billions of devices connected altogether. Despite there is no one technology able to cope with all possible scenarios, LPWAN solutions are emerging as viable technologies for implementing private, low-cost cellular like wireless networks. Distributed systems could leverage this approach as a driving technology for services as smart environment...
Reflection radio principles, used in RFID systems, have been recently exploited in wireless sensor networking, due to their inherent low-power requirements. This work offers a complete batteryless analog sensor design, implemented and tested in real-world conditions, able to backscatter its sensed information, without any type of analog-to-digital converter (ADC), digital logic or dedicated illuminator,...
Recent advances in self-interference cancellation (SIC) techniques have made the implementation of Full Duplex (FD) possible. FD technology promises doubling the capacity of wireless networks without needing new frequencies, by enabling communication devices to receive and transmit at the same time and frequency. However, when considering the overall communication networks, gains may be less significant...
The high demand for wireless Internet including emerging Internet of Things (IoT) applications is putting extreme pressure on better utilisation of the available radio spectrum. The expected spectrum “crunch” requires highly efficient radio resource management schemes with low complexity and high responsiveness to the changing network conditions. Spectrum sharing is regarded as an essential approach...
In this paper, big Radio Frequency (RF) data assisted optimization is considered for future wireless networks employing cognitive radio technology with machine learning capability. A cognitive radio network (CRN) with multiple Secondary Users (SUs) may coexist with other wireless systems such as Small Cells (SC) and Radar systems, both Primary Users (PUs) with different level of priorities. Traditional...
Channel assignment is a key problem in Cognitive Radio Networks. The channels are leased to the secondary users when the licensed or primary users are OFF, provided that the secondary users will leave those channels as soon as the primary users are reactivated. Therefore, to achieve a high performance of the network, we should lease a channel to a secondary user while both of them achieve the best...
Efficient estimation of depth from pairs of stereo images is one of the core problems in computer vision. We efficiently solve the specialized problem of stereo matching under active illumination using a new learning-based algorithm. This type of active stereo i.e. stereo matching where scene texture is augmented by an active light projector is proving compelling for designing depth cameras, largely...
In this paper we present a novel dynamic spectrum sensing and access model in cognitive radio networks. This model allows secondary user (SU) to sequentially sense two times if necessary due to the false alarm, and choose different accessing manner according to the sensing result. In practice, sensing results often affect the data transmission in cognitive radio systems. Therefore, a hybrid interweave/underlay...
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