The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
We present a cooperative compressed sensing scheme for wide-band spectrum detection in cognitive radio where analog-to-information converter are applied to map a continuous-time signal to a discrete sequence of measurements. The measurements are collected from each second user to a fusion center where a novel cooperative compressed sensing recovery algorithm named SCSMP is utilized to reconstruct...
In this paper, a comparison among different cooperative spectrum sensing approaches is provided. It is assumed that the secondary terminals autonomously perform local spectrum sensing and forward their decision to a fusion center. It combines the received data to obtain the global decision, i.e. the presence or the absence of the primary user in the monitored environment. In particular, three fusion...
Spectrum sensing, the cornerstone of the Cognitive Radio paradigm, has been the focus of intensive research, from which the main conclusion was that its performance can be greatly enhanced through the use of cooperative sensing schemes. In this paper we analyze the performance of a cooperative spectrum sensing scheme, by measuring the perceived capacity limits introduced by the use of data fusion...
Cognitive radios are efficient techniques to improve the utilization of the spectrum. Spectrum sensing is the key functionality to improve the spectrum efficiency and avoid harmful interference to the licensed users. By exploiting the spatial diversity of the different secondary users, cooperative sensing can achieve better sensing performance compared to the local sensing, thereby, receiving much...
Cognitive radio (CR) has emerged as a solution to the problem of spectrum scarcity as it exploits the transmission opportunities in the under-utilized spectrum bands of primary users. Collaborative (or distributed) spectrum sensing has been shown to have various advantages in terms of spectrum utilization and robustness. The data fusion scheme is a key component of collaborative spectrum sensing....
Among variant kinds of spectrum sensing strategies in cognitive radio (CR) broadly studied before, cooperative sensing is the most popular one to detect the primary user accurately. This paper proposes a new cooperative spectrum sensing algorithm in which double threshold energy detection will be employed at local decision and different fusion rules will be used at the fusion center. Theoretic analysis...
In cognitive radios, the first and crucial task is to detect the spectrum holes or the presence of primary user by employing spectrum sensing. However, there exist two kinds of detection errors (i.e., miss-detection error and false-alarm error), which degrade the sensing performance severely. Aiming at minimizing the probability of total detection errors, based on the law of total probability we propose...
Cooperative spectrum sensing enables a Cognitive Radio (CR) networks to reliably detect primary users and avoid causing interference to primary user's communications, and data fusion technique is a key component of it. However, when the number of CR users tends to be large, the bandwidth for reporting their sensing results to the fusion center will be very enormous. In this paper, censoring schemes...
The cooperative operation can improve the sensing performance of cognitive radio networks and reduce the sensing time. Combining multiple cognitive users' local detection results and making accurate judgment is essential to improve cooperative gain. According to uploaded information from cognitive users, hard decision based on the combination of large numbers and soft decision based on the confidence...
In this paper, we propose two novel data fusion schemes for cooperative spectrum sensing in the IEEE 802.22 WRAN system. The data fusion structure is proper for the WRAN system due to its centralized structure, and it can provide reliable sensing performance. The proposed data fusion schemes improve the sensing reliability by utilizing confidence vector of the sensing result. Moreover, application...
Spectrum sensing is an essential mechanism in a cognitive radio network. However, the detection performance will be greatly degraded when few untrusted secondary users exist which can be identified as 'Always Yes' users and 'Always No' users. In this paper, we propose an energy detector with double thresholds combined with revised data fusion rules to find these untrusted users and counteract their...
As an enabling functionality of overlay cognitive radio networks, spectrum sensing needs to reliably detect licensed signal in the band of interest. To achieve reliable sensing, we propose a linear fusion scheme for distributed spectrum sensing to combine the sensing results from multiple spatially distributed cognitive radios. The optimal linear fusion design is formulated into a nonconvex optimization...
Opportunistic access to temporarily unused licensed frequency bands has been recognized as a cost-effective solution to mitigate the scarcity of radio spectrum incurred by the proliferation and evolution of wireless devices. In order to accomplish a more efficient spectrum utilization across time, space and frequency, the functionality of spectral awareness is expected to be incorporated into transceivers...
In this paper, in order to improve the sensing performance which can be severely degraded when the sensing observations are forwarded to fusion center through fading channels, we apply the clustering method into cooperative spectrum sensing by forming all the secondary users into a few clusters and selecting the most favorable user in each cluster to report sensing results to the data fusion center...
In this paper, we investigate cooperative sensing schemes to identify primary signals in fading environment for cognitive radio (CR) networks employing energy detectors. We consider a parallel fusion architecture in which all the sensing devices send their quantized sensing information to an access point, which then applies a fusion rule to determine the presence of the primary signal. We assume independent...
In emerging cognitive radio (CR) networks with spectrum sharing, the first cognitive task preceding any dynamic spectrum access is the sensing and identification of spectral holes in wireless environments. This paper develops a distributed compressed spectrum sensing approach for (ultra-)wideband CR networks. Compressed sensing is performed at local CRs to scan the very wide spectrum at practical...
For target tracking in Interference Environments of cognitive radar problem, Extended Karman, Particle filter algorithms etc. are generally used to be regarded as usual solutions to state estimation. Many techniques have been developed to improve performance of target tracking. In this paper, we set the structure and key features of target's tracking design for cognitive radar, and newly propose cognitive...
Cooperation between cognitive radio nodes is indispensable in order to mitigate the sensitivity requirement on individual radio and increase the reliability of spectrum sensing. Normally the fusion network is in parallel configuration and the conventional fusion rules are the k out of N rules because of their simplicity to manage. When the detection nodes are similar with each other i.e. their observations...
Distributed spectrum sensing (DSS) enables a Cognitive Radio (CR) network to reliably detect licensed users and avoid causing interference to licensed communications. The data fusion technique is a key component of DSS. We discuss the Byzantine failure problem in the context of data fusion, which may be caused by either malfunctioning sensing terminals or Spectrum Sensing Data Falsification (SSDF)...
In emerging cognitive radio (CR) networks, the first cognitive task preceding any dynamic spectrum management is the sensing and identification of spectrum holes in wireless environments. This paper develops a distributed compressed spectrum sensing approach for (ultra-)wideband CR networks. First, compressive sampling is performed at local CRs to scan the very wide spectrum at practical signal-acquisition...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.