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In this paper, we consider the problem of hierarchical bandwidth sharing in cognitive radio (CR) environment. In the system model under consideration, a primary service provider (PSP) can sell its available spectrum bandwidth to a secondary service provider (SSP). In contrast to the conventional schemes, the SUs served by the SSP can also share the unsold bands of the PSP through the approach of opportunistic...
In recent years, filter bank multicarrier (FBMC) has recaptured widespread interests for its possible applications in cognitive radio and dynamic spectrum access. A distinctive feature for cognitive radio is its adaptivity to environment. When environment changes, a cognitive radio will change its parameters to optimize the transmission and receiving. Thus it is desirable to design a unified structure...
The basic notion behind Cognitive Radio (CR) is that secondary users (SU) access the under-utilized licensed spectrum of primary users (PU) in an opportunistic manner. It assuages the problem of spectrum scarcity, which is a major concern as many applications and devices nowadays are using wireless medium. Before carrying on any transmission, the SU senses the licensed spectrum and predicts whether...
The FCC new regulation for cognitive use of the TV white space spectrum provides a new means for improving traditional cellular network performance. But it also introduces a number of technical challenges. This paper studies one of the challenges: given the significant differences in the propagation property and the transmit power limitations between the cellular band and the TV white space, how both...
The low spectrum utilization has limited the development of wireless communication is a common view In Cognitive Radio (CR). And the idle spectrum holes are too narrow to support high-speed communication is an another problem. The spectrum aggregation technology is supposed a hopeful method for the secondary users (SU) access to the idle spectrum. In order to improve the spectrum utilization, a spectrum...
In this paper, a cooperative cognitive radio networking framework, which enhances the security of communications for the primary users (PUs) and provides transmission opportunities to secondary users (SUs), is proposed. Particularly, a PU selects two cooperating SUs, a relay SU and a jammer SU, for improving communication secrecy and grants a fraction of the bandwidth resource as a reward to the SUs,...
In cognitive radio networks, the available vacant frequency bands, referred to as spectrum holes, are usually discontinuous. Hence, it is hard to exploit these vacant frequency bands since the bandwidth of single one may not be able to meet the wide bandwidth requirement of secondary users (SUs). Spectrum aggregation (SA) enables SUs to access several discontinuous spectrum holes simultaneously to...
This article presents results of the LTE Femtocell mitigation interference simulations for cognitive radio implementation. The simulations have been performed using the SEAMCAT software at 700 MHz with a 10 MHz bandwidth, considering indoor and outdoor propagation environments. The result is the evaluation of the reduction of cross-tier interference obtained by applying the cognitive radio technology...
Dynamic spectrum sharing plays a critical role in cognitive radio for the efficient spectrum utilization. In this paper, we consider a cooperative spectrum leasing model, in which the primary user (PU) may lease part of its bandwidth to the secondary user (SU) in exchange for the cooperation to maximize its power saving, under the constraint that its target is guaranteed. In return, the SU can take...
With the burgeoning popularity & necessity of all things wireless, the radio spectrum has become a scarce utility; cognitive radio (CR) is now the relevant technology under development that enables one to utilize the spectrum more efficiently. Here we propose a new artficial neural network (ANN) model that predicts the channel capacity of the received signal. This information is analyzed theoretically...
We consider the problem of designing an effective sampling scheme for sparse multi-band signals. Based on previous results on periodic non-uniform sampling (Multi-coset) and recent advances in Compressive Sensing (CS), we propose a new sampling scheme, the Dynamic Single Branch Non-uniform Sampler (DSB-NUS). Our scheme estimates the spectral support using non-uniform spectrum sensing technique to...
Multi-antenna-based spatial multiplexing exhibit high potential for enhancing the system performance of future cognitive radio networks [1]-[3]. This paper proposes a novel cooperative spectrum sensing approach that utilizes coordinated beamforming and node clustering. It provides a generic framework that can be exploited by any cooperative spectrum sensing and fusion technique. The performance analysis...
The concept of cognitive radio (CR) technology is emerging as a new paradigm for designing next generation wireless networks with dynamic spectrum sharing. Game theory is one of key mathematical tools to model and analyze the spectrum sharing process. In this paper, an environment where multiple licensed service providers compete to sell spectrum to infrastructure based CR networks is investigated...
A miniature frequency bandwidth reconfigurable antenna is presented. Four slots and a ring slot resonator are integrated to the ground plane of an UWB antenna in order to achieve frequency reconfiguration, maintaining the original size unchanged. The proposed antenna is capable of adjusting both the frequency and the bandwidth by using switches to control the electrical length of the slots, offering...
We propose algorithms to address the channel allocation and fairness issues of multi band multiuser cognitive ad-hoc networks. Nodes in the network have unequal channel access probability and have no prior information about the offered bandwidth or number of users in the multiple access system. In that nodes use reinforcement learning algorithm to predict future channel selection probability from...
In this paper, we investigate the performance of the dynamic allocation of resources between separate cellular networks. We propose a Dynamic Internetworking Carrier Aggregation (DI-CA) framework which involves every network operator releasing some of its exclusive, but excess, spectrum to another network operator for a limited time. We derive the basic condition for which DI-CA can improve the performance...
This paper presents a software radio implementation for spectrum hole sensing in cognitive mobile networks. We propose a multi-channel spectrum sensing method for spectrum hole detection, exploiting Fast Fourier Transform (FFT) filter bank (FFTFB). Our method tests multiple frequency bands at the same time, detecting multiple spectrum holes at once. We modify a recently introduced two-dwell sensing...
In cognitive radio networks, spectrum sharing among secondary users can benefit from having more transmission opportunities through spectrum handoff. However, the spectrum sharing strategy can also increase negatively the number of performed handoffs. In this work, we study formally the impact of spectrum sharing on spectrum handoff and at the same time the impact of the spectrum handoff on the overall...
Cognitive radio networks are developed to solve the under utilization problem of available spectrum. Typically, available spectrum is not fully utilized without supporting multimedia applications. In this work we translate video routing in a dynamic cognitive radio network into a decision theory problem. Then terminal analysis backward induction is used to produce our routing scheme that improves...
Nowadays, radio systems have to use the spectrum resource more intensely than in the past to meet the demanding expectations of the users. Several studies have demonstrated that portions of radio spectrum are not in use for significant periods of time, showing the necessity to design a more flexible way to manage the spectrum resource with respect to the traditional frequency allocation policy.
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