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This paper presents an analyzing on the prediction of a primary signal in cognitive radio networks using a hybrid algorithm based on two parts, know as: an alpha-beta filter and a neyman-pearson (NP) detector. Today, it is important to predict a primary signal in a cluttered environment and especially when the secondary user (SU) is moving. However, the challenges of this contribution are based on...
State-of-the-art sensing methods mostly exploit spectrum holes (SHs) in conventional frequency, time, and geography dimensions, which can hardly satisfy the increasing throughput demand of CR networks. Meanwhile, the rapid development of multi-antenna technology makes the terminal obtain the angle recognition capability. Motivated by this, this paper analyzes SHs from the angle/space domain and design...
The spectrum sensing is a vital stage in cognitive radio networks. The performance of energy-based spectrum sensing scheme degrades under noise uncertainty, which can be improved by covariance-based sensing methods. In this paper, a double threshold-based spectrum sensing scheme using sample covariance matrix of received signal is presented, that improves the performance of conventional covariance-based...
Cognitive radio (CR) is a form of wireless communication in which a transceiver can wisely detect communication channels that are in use and those which are not, and immediately move into vacant channels while avoiding occupied ones. In such systems, spectrum sensing (SS) is a crucial operation. It consists to detect the available frequency bands. Many spectrum sensing techniques are presented in...
Wireless communication users are increasing day by day which in turn leads to scarcity for spectrum. In order to overcome this problem, cognitive radio is the booming solution. Cognitive radio (CR) is an intelligent radio that can be programmed and configured dynamically. One of the important tasks of cognitive radio is to sense the free spectrum. The availability of the signal is decided by comparing...
In cognitive radio, the secondary user (SU) can only utilize the spectrum hole with assurance of sufficient protection to the licenced primary user (PU). In this paper, a reliable spectrum sensing scheme based on eigenvalue of sample covariance matrix of received signal is proposed. The conventional energy-based detection method is highly vulnerable under noise uncertainty and eigenvalue-based method...
In cognitive radio networks, the performance of energy detection will be degraded significantly due to the cluster overlapping caused by noise uncertainty. To alleviate the noise uncertainty effect, a novel machine learning algorithm is proposed in this paper for cooperative spectrum sensing. The proposed algorithm incorporates fuzzy support vector machine and nonparallel hyperplane support vector...
The ability to provide accurate spectrum sensing and decision making under an uncertainty environment is proving useful for the military SATCOM to increases the spectrum utilization. Dynamic spectrum access(DSA) allows a secondary user to access the spectrum holes that are not occupied by the primary users. However, the spectrum sensing for DSA is normally performed in a complex SATCOM environment...
In cognitive radio spectrum sensing is a fundamental problem. Under the case of uncorrelated noise different methods are used for spectrum sensing. In this paper we compare the performance of MP and eigenvalue based methods. In eigenvalue based method we find the threshold using random matrix theory (RMT). Marchenko-Pastur (MP) method use standard condition number (SCN) to find the threshold. Here...
Spectrum sensing is one of the main parts in cognitive radio. The performance of the adopted spectrum sensing method is very important. When the primary user and the cognitive radio are in operation simultaneously, performance of spectrum sensing is damaged. We propose to apply the linear prediction for the blind source separation algorithm as an alternative for more conventional techniques. Simulation...
Noise estimation is an essential issue on the wireless communication system. Cognitive radio network uses the spectrum sensing to detect opportunistically the unoccupied spectrum holes and the licensed user. Several methods of spectrum sensing need the knowledge of noise power in advance. In this paper, we proposed noise power estimation that suitable for the condition of cognitive radio. The estimator...
In diversity-based multiple antenna cognitive radio system, the performance of the existing cooperative spectrum sensing algorithms based on covariance matrix degrades seriously due to the channel correlation. In this paper, we formulate spectrum sensing as a multinomial distribution test problem, and then apply the Discrete Anderson Darling (DAD) test, one of discrete goodness of fit tests, to examining...
In this paper, we consider the problem of optimal opportunistic spectrum access using full-duplex (FD) radios in presence of uncertain primary user (PU) channel statistics and propose a Sensing-and-Selectively-Transmit protocol (SaST). To optimize its throughput, the SU sensing period has to be carefully tuned. However, in absence of the exact knowledge of PU activity statistics, under SaST, the PU's...
In hard decision cooperative spectrum sensing (CSS), each secondary user (SU) or simply cognitive radio user (CR) senses the primary user (PU) activity via a Sensing channel (S-channel) and forwards its own binary decision to a fusion center (FC) via a Reporting channel (R-channel) to make a final decision regarding PU existence. In practical scenarios, both S-channels and R-channels are contaminated...
Spectrum Sensing is elementary function in Cognitive Radio Networks (CRN) to identify the white spaces in spectrum for opportunistic communication. In this paper, we proposed a novel two stage spectrum sensing under the environment as noise uncertainty. The robustness of uncertainty of noise power is one of the main challenges in spectrum sensing method. Since detection of primary users (PU) in the...
In cognitive radio networks, secondary users (SUs) utilize the unused spectrum slots in the assigned band for the primary users (PUs). Conventional cognitive radio networks operate in half-duplex (HD) mode. Recently, full-duplex (FD) communication has become feasible. SUs with full-duplex capabilities can sense the spectrum and transmit simultaneously, which improves the efficiency of cognitive radio...
The existing blind noise estimation called cyclic prefix based noise estimation without knowledge of a priori signal is simulated along with input of DVB-T and the multipath channel ITU-T pedestrian model A. The simulation is done by means to know NMSE and noise uncertainty over time observation with varied SNR. The NMSE shows a very good result and close to the result of the previous research. The...
Fast growth of wireless communication demands more spectrum but it is a limited resource. Survey conducted by Federal Communications Commission (FCC) shows that spectrum allocated to the primary user (PU) is underutilization. Cognitive Radio (CR) is proposed to improve the utilization of underutilized spectrum. In CR, spectrum sensing is a key technology for opportunistic spectrum access. To reduce...
Cognitive Radio Networks (CRNs) is an emerging wireless communications technique for resolving the significant spectrum scarcity problem. Despite its promising characteristics, CRNs also introduce new security threats especially the internal attacks during the spectrum sensing process, which can degrade the efficiency of spectrum sensing. To address this issue, this paper proposes a distributed cooperative...
Spectrum sensing is the most appropriate method performed by cognitive radio for the efficient utilization of RF spectrum without any harmful interference to the primary users. In this paper, we propose various spectrum sensing technique. Based on spectrum sensing, cooperative sensing is done over various spectrum sensing technique to overcome the problem of miss detection and false alarm which is...
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