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In this paper, the spectrum map of speech samples is used to identify patients with vocal polypus. Comparing the spectrum map with impulse response in wireless communication channels, statistical characteristic root-mean square-delay spread (RMSD) and standard deviation (SD) are employed to describe the speech frequency domain characteristics. Fuzzy logic system (FLS) is used to make polypus patients...
This letter addresses the problem of spectrum sensing over fading channel, in which a licensee and multiple unlicensed users coexist and operate in the licensed channel in a local area. We derive the overall average probabilities of detection and false alarm by jointly taking the fading and the location of SUs into account and employing the energy detection as the underlying detection scheme. Furthermore,...
This paper addresses the problem of joint optimization of subchannel selection and spectrum sensing time for multiband cognitive radio networks. In particular, we construct a multiband spectrum sensing framework, and derive the probabilities of detection and false alarm taking the different subchannel gain into account. Furthermore, we formulate the multiband sensing as a two-parameter optimization...
Spectrum sensing is one of the most important technologies for cognitive radio. In order to decrease the effect of low SNR, and increase the reliability spectrum sensing performance, we propose a novel spectrum sensing approach, which collects the distributed collaborative beamforming signals as the test statistic to input the energy detector. In particular, the collaborative beamforming method can...
In this paper, we propose a channel estimation approach based on Bayesian compressive sensing that has the advantage of computation simplicity, noise robust to some extent and the sparse result. UWB channel estimation is absolutely vital to the design of the receiver and is predicament of the UWB system implement. We show that our proposed method relies on the time domain sparse of the impulse response...
To distinguish the polypus patients, the spectrum map of the speech samples is used to analyze. Compared the spectrum map with impulse response in wireless communication channel, statistical characteristic root-mean square-delay spread (RMSD) and standard deviation (SD) are employed to describe the speech frequency domain characteristic. Fuzzy logic system (FLS) is used to make polypus patients diagnosis...
Bayesian compressive sensing (BCS) utilizes the prior distribution of signal coefficients to reconstruct the original signal. The widely used prior is Laplace and Gaussian distributed. In this paper, we use the scene of L sets of signal sparse coefficients which are statistically related and take advantage of Laplace prior and statistically interrelationship among signals to propose the Laplace prior...
In this paper, we propose an efficient power allocation scheme that aims at maximizing the system throughput in joint spectrum overlay and underlay cognitive radio network. We show that our proposed scheme enlarges the achievable throughput region comparing to the overlay strategy, and causes less interference than the underlay strategy. In addition, since the unlicensed users adopting the overlay...
In this paper, we propose a power control algorithm using game theory for cognitive radio networks. A novel framework is presented to meet different SIR constrains which can guarantee the cognitive radio user's QoS requirement. We define a cost function which can effectively control the network power consumption. With the given cost function, the second user can achieve a better performance related...
For these communication systems whose transmitted waveforms have a much closed signal space, such as the attractive Ultra Narrow-band (UNB) modulation technology, it is rather toilsome to obtain the satisfactory performance because of the difficulty in accurately determining the threshold of the optimum receiver, which is mainly caused by its tiny waveform dipartition as well as the unruly DC variant...
In this paper, we investigate the optimal power allocation strategy in the joint spectrum overlay and underlay cognitive radio network where a licensee and multiple unlicensed users coexist and operate in the same spectrum. We propose an optimal power allocation scheme which achieves the maximum system utility while satisfying the QoS requirement of SUs and interference constrains of the PU. Particularly,...
This paper initiatively puts forward a novel synthesis design for generating UWB narrow pulse by using CI (Carrier Interference) subcarrier waveform synthesis and Bessel function expansion. Through adaptively adjusting the initial phases of multiple sub-carriers according to the location information, CI (Carrier Interference) sub-carrier waveform synthesis signal could achieve better performance....
In practical cognitive radio networks, the topology is constantly changing since the primary and secondary users join and leave the network at any moment. So it is very important to design a distributed spectrum offering scheme that can coordinate the spectrum offering scheme adapt to dynamic topology with only local information. In this paper, we propose a game-based distributed spectrum offering...
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