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Electromagnetic interference can degrade radio receiver severely. For this purpose, there is a need to monitor and quantify interference incidents in radio frequency bands. With this goal, a detection method is developed that is intended to be used in a portable detection system for interference detection in frequency bands, where radio transmissions are sporadically appearing. The method is used...
In this paper are presented the results obtained after of evaluating three techniques of blind detection of spectrum holes used in Cognitive Radio (CR). The techniques evaluated correspond to the general technique of detection of energy levels, the method LAD BASED and the technique based on forward methods. The operation of these techniques was tested in simulation scenarios of a telecommunications...
In this paper, we propose an intelligent cognitive radar system for detecting and classifying the micro unmanned aerial systems (micro UASs). In this system, we design a low-complexity binarized deep belief network (DBN) classifier that recognizes the signature patterns generated by using a Doppler radar based solution. To generate the distinguishable patterns, our work employs the spectral correlation...
In this paper, the performance of direct current informative subcarrier intensity modulation (DCI-SIM) which is proposed to enhance the power efficiency of subcarrier intensity modulation (SIM) is investigated in visible light communication. The BER performance of DCI-SIM is compared with SIM, pulse amplitude modulation (PAM) and, enhanced unipolar orthogonal frequency division multiplexing (eU-OFDM)...
A Walsh Hadamard Transform (WHT) employed in discrete wavelet transform (DWT) based novel OFDM (DWT-WHT-OFDM) method has been proposed as a solution to the problem of error floor of time domain channel equalizer (TDE) used in multi carrier communication systems in this paper. Computer simulations have been performed to show the performance of the proposed method in frequency selective Rayleigh fading...
Authentication that is based on Biometrics traits is more secure for many applications like cryptosystems, therefore; the template of stored biometric members of the biometric authentication system is a dangerous issue, while it can be stolen or breached. We produce in this paper an automatic evaluator depending on the biometric performance measures FAR, FRR and EER by simulating how noise in the...
Speech is one of the efficient communication medium; if it can be recognized by machine then human interaction can be improved. As the noise produced by various ambient sources like vehicles normally lies in this frequency range, speech signals get easily distorted by the ambient noises or AWGN. The degraded speech therefore needs to be processed for the enhancement of the speech components. The aim...
Cognitive Radio (CR) is an intelligent system for opportunistically accessing the idle resources and a solution for spectrum resources scarcity. The main purpose of this article is to analyze the performance of Energy Detection under Nakagami and Rayleigh fading channels and compare it with the case of when there is only AWGN. Probability of detection and probability of false alarm are used to characterize...
This paper describes a joint detection and classification of OFDM/QAM, OFDM/OQAM and SC-FDMA signals, using their cyclic frequency domain profiles of spectral correlation density. Detection and classification are performed by introducing corresponding HMMs of these signals. Some performances of the considered joint detection and classification of these signals, obtained using software simulation models,...
In this paper, a class of OFDM systems with Continuous Phase Modulation (CPM) mapper signals is discussed and theoretical predictions for symbol error probabilities are derived, where the memory is employed to improve system performance. Previously, results summarized that binary data of OFDM systems with CPM mapper is mapped with complex symbols using the concept of correlated phase states of CPM...
Event Related Potentials (ERPs) are generated in ongoing brain electrical activity due to visual, auditory, or sensory stimuli. These signals have very low SNR and are contaminated by background EEG. Extraction of single trial ERPs from background EEG is a challenging task due to overlapping nature of the frequency bands of ERP and EEG signals and much higher power of EEG than ERPs. In this paper...
To solve the problem of estimating the signal-to-noise ratio (SNR) of LFM signal with unknown parameters, an SNR estimation algorithm is presented in this paper, which is based on the Fourier series' fitting of the auto-correlation's main lobe in time domain. Firstly, the LFM signal's auto-correlation is analyzed to deduce the relationship between the SNR and the auto-correlation in the background...
In this paper, the concept of varying modulation parameters with respect to time is applied to multi-level Continuous Phase Chirp Modulation (M-CPCM). These multi-mode M — CPCM signals are described and illustrated. Coherent detection of multi-mode M-CPCM in AWGN channel is addressed and the structure of the optimum receiver is derived and a closed-form expression for its symbol error rate is given...
A novel frequency domain channel equalizer, inspired by [1], based on discrete wavelet transform (DWT) based OFDM has been proposed to improve the frequency domain channel equalizer employed OFDM systems in this paper. In this study, the performance of DWT based OFDM frequency domain channel equalizer (DWT-OFDM-FDE) has been compared with the conventional FFT based OFDM (FFT-OFDM-FDE) systems. Computer...
Spectrum sensing is one of the highly researched and focused area in cooperative cognitive networks. Energy and Cyclostationary Spectrum detection are the mostly used and efficient spectrum sensing techniques to detect the presence or absence of the primary user and to avoid interference. In this paper, the performance of Energy and Cyclostationary spectrum detection over Rayleigh, Nakagami and Additive...
In this paper, a cooperative spectrum sharing protocol is proposed for cognitive radio networks (CRNs) which operates in underlay mode with an automatic repeat-request (ARQ)- based primary user (PU) including primary transmitter (PT) and primary receiver (PR) nodes and a bidirectionally communicating secondary user (SU) which consists of the nodes S1 and S2. In ARQ-based PU, ACKnowledgement/Negative-ACKnowledgement...
Generalised frequency division multiplexing (GFDM) is one of the promising contenders for fifth generation (5G) wireless communications. It is of great interest as it shows a number of advantages over cyclic prefix orthogonal FDM (CP-OFDM). However, the non-orthogonality scheme of GFDM introduces intersymbol and intercarrier interference (ISI/ICI). In order to mitigate these effects we explore the...
In this paper, a spectrum sharing protocol that combines coordinate-interleaved orthogonal design (CIOD) and space-time block coding is proposed for cognitive radio (CR) networks. Primary system's transmitter (PT) and receiver (PR) are equipped both by one antenna while secondary system's transmitter (ST) and receiver (SR) are equipped by two and one antennas, respectively. CIOD applied by means of...
In this paper, Two communication protocol which are designed for telemedicine field, have been tackled. BER performance values of IEEE 802.15.6 Wireless Body Area Network (WBAN) and IEEE 802.15.4 ZigBEE/BT4.0 Communication Protocol's Narrow Band Physical Layer (NB PHY) on Rayleigh fading Channel and Additive White Gaussian Noise (AWGN) Channel has been compared with each other.
We investigate the outage probability of a variablegain amplify-and-forward (AF) relay network. A multi-source multi-relay network is considered with one destination and twoway traffic, where each node is equipped with two antennas and works on a full-duplex (FD) transmission mode. Meanwhile, the number of sources and relays is M and N, respectively. The residual self-interference, leaking from the...
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