We investigate the performance of asymmetric radio frequency (RF) and free-space optical (FSO) dual-hop cognitive amplify-and-forward relay networks where RF links are subject to independent nonidentically distributed Nakagami-m fading. consider that link transmitter receiver secondary users an underlay network. Specifically, transmit power conditions proposed spectrum-sharing network governed by either combined constraint interference on primary maximum transmission at network, or single...

The theory of adaptive sequence detection incorporating estimation channel and related parameters is studied in the context maximum-likelihood (ML) principles a general framework based on expectation maximization (EM) algorithm. A generalized ML (GMLSDE) criterion derived EM approach, it shown how per-survivor processing per-branch methods emerge naturally from GMLSDE. GMLSDE developed into real time detection/estimation algorithm using online with coupling between detection. By utilizing...

Recursive (online) expectation-maximization (EM) algorithm along with stochastic approximation is employed in this paper to estimate unknown time-invariant/variant parameters. The impulse response of a linear system (channel) modeled as an deterministic vector/process and Gaussian characteristics. Using these models which are embedded white or colored noise, different types recursive least squares (RLS), Kalman filtering smoothing combined RLS Kalman-type algorithms derived directly from the...

We present a novel method to remove eye blink artifacts from the electroencephalogram (EEG) signals, without using electro-oculogram (EOG) reference electrodes. first model EEG activity by an autoregressive and output-error model, then use Kalman filter estimate true based on integrating two models. The performance of proposed is evaluated different metrics Dataset IIa BCI competition 2008. For RLS algorithm, artifact removal distortion are 7.35 0.79, while for our these 9.53 0.84,...

Localization is one of the fundamental tasks in wireless sensor network. Measuring time arrival (TOA) and difference a signal (TDOA) are two widely used criteria for localization. In TOA based schemes target must be synchronous with anchors while can asynchronous TDOA schemes. this paper, we propose localization scheme on measuring inhomogeneous underwater environment. One properties that waves travel over curved path due to inhomogeneity underwater. This phenomenon makes different problem...

In this paper, we investigate the performance of asymmetric radio frequency (RF) and free space optical (FSO) dual-hop cooperative relay network along with a direct RF link between source destination. The FSO experiences double generalized Gamma turbulence in presence non-zero boresight pointing errors, links experience non-identically distributed Nakagami-m fading. Moreover, considering both cognitive non-cognitive scenarios, partial selection (PRS) strategy has been employed. Furthermore,...

Multiple-input multiple-output (MIMO) system using orthogonal frequency division multiplexing (OFDM) technique has become a promising method for reliable high data-rate wireless transmission in which the channel is dispersive both time and domains. Due to multiple cochannel interferences MIMO system, accuracy of estimation vital factor proper receiver design order realize full potential performance MIMO-OFDM system. A robust improved algorithm proposed this paper systems based on least...

Orthogonal-frequency-division-multiplexing/offset quadrature amplitude modulation (OFDM/OQAM) based multicarrier system achieves better spectral efficiency in comparison with the widely used OFDM system. However, OFDM/OQAM suffers from intersubchannel interference and intersymbol frequency-selective channels, which cause poor bit error rate (BER) performance. To overcome these challenging issues, this paper, we propose a per-subchannel joint equalizer receiver filter design method on...

Abstract This paper proposes a new prototype filter design method based on the time‐frequency constellation for bank multicarrier (FBMC) systems in highly doubly dispersive channels. Maximal spectral efficiency, complex orthogonality and well‐localised pulse shaping time frequency domains are three criteria design. Satisfying these simultaneously is challenging issue FBMC system In order to meet as much possible, we consider an which complex‐valued data symbols transmitted via selected with...

The idea of adaptive state allocation (ASA) algorithm is used in this paper to substantially reduce the computational complexity maximum-likelihood sequence detection and estimation (MLSD/MLSDE) receiver without a significant degradation its performance. In ASA algorithm, total number states assigned trellis selected from entire set are changed adaptively based on short-term power channel impulse response (CIR) or estimate. combination two methods: threshold (AT) partitioning (AP). AT...

A new channel estimation algorithm for OFDM systems is proposed in this paper based on a noise reduction method. The performance of least squares (LS) estimator improved by using the colored characteristics LS impulse response (CIR). noise, which CIR (signal) subspace, estimated and suppressed correlation between two parts are within outside signal subspace. Knowledge statistical parameters not needed as long length longer than cyclic prefix interval.

Singular value decomposition (SVD) is a useful technique to mitigate co-space interference (CSI) in multiple input output (MIMO) systems employing orthogonal frequency division multiplexing (OFDM) scheme. The SVD based frequency-domain broadband beamforming (FBBF) approach uses the matrices both transmitter and receiver sides for each subchannel matrix. However, when MIMO- OFDM system has large number of subchannels, FBBF very complex due computing separately. In this paper, we propose new...

Transmission of information in nano-networks can be implemented by the emission and reception molecules diffusion-based molecular communications. Since propagation environment is shared among multiple nodes, emitted different transmitters cause interuser interference (IUI). In this paper, we propose code division access (MCDMA) to overcome IUI caused transmitted signals from asynchronous users. Based on adopting on-off keying (OOK) modulation scheme implementing codes, develop a chip...

A distributed adaptive algorithm for estimation of sparse unknown parameters in the presence nonGaussian noise is proposed this paper based on normalized least mean fourth (NLMF) criterion. At first step, local NLMF modified by zero norm order to speed up convergence rate and also reduce steady state error power conditions. Then, extended scenario which more improvement performance achieved due cooperation filters. Simulation results show superiority comparison with conventional algorithms.

A new method is proposed in this paper to design the time-domain equalizer for orthogonal frequency division multiplexing systems based on maximizing signal-to-interference-plus-noise ratio (SINR) at output of equalizer. The called Maximum SINR Time-domain Equalization (MSINR-TEQ) derived a formulation SINR. Computer simulation and analytical results show performance MSINR-TEQ its superiority comparison with much-used channel impulse response shortening.

We propose an adaptive estimation algorithm for channel matrix singular value decomposition (SVD) in multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) systems. The SVD method is efficient approach to design space-time coding/decoding and detection algorithms MIMO-OFDM However, the may involve complex nonlinear optimization methods. proposed developed based on a two-step recursive by utilizing linear constrained least mean square (LMS) technique.

In this paper, a new algorithm is proposed for cooperative beamforming and power allocation (CBPA) in the downlink of multi-input multi-output (MIMO) cognitive radio systems. Increasing efficiency spectrum usage main goal systems by servicing number secondary users addition to primary user. The CBPA developed based on criterion which total signal interference plus noise ratio (SINR) maximized subject guarantee user's quality service maximum transmit power. addition, provides same all users....

Joint transmitter and receiver beamforming algorithms for uplink multiuser multi-input multi-output (MIMO) communication systems are proposed in this paper based on maximizing an utility function, which is defined the difference between desired signal power interference plus noise power. Two iterative developed by function of each user via parallel serial methods. In method, vectors iteratively updated its function. However at first step, all users then calculated. By computer simulations,...

A hierarchical structure for mobile positioning in cellular communication systems is proposed this paper based on multi-layer perceptron neural networks. The location of the phone estimated combining angle arrival (AOA) and time (TOA) determination methods implemented by a network. coverage area each base station divided to different cells at level structure. estimation improved using new network that has been trained smaller cell. Simulation results an urban show method achieves good...

An iterative algorithm is proposed in this paper to estimate the singular value decomposition (SVD) of multiple-input multiple-output (MIMO) channel from received signal. The based on constrained minimum mean-square error (MMSE) criterion. For different numbers transmitter and receiver antennas, simulation results show that achieves good performance with respect SVD estimation MIMO matrix.

In this paper the problem of ranging between two nodes in a wireless network acoustic sensors underwater medium is addressed. One fundamental issues sensor networks (UWSNs) to determine location which mostly performed by utilizing range estimation unknown and anchor nodes. general, via measuring either time arrival (ToA) signal or received strength (RSS). Previous studies dealt with determining sensors' environment assumption straight line wave propagation. However, fact that waves travel...

A novel discrete tracking algorithm for mobile user based on velocity estimation in microcellular urban environment is proposed this paper. By partitioning the path and defining each partition as a state, tracks hidden Markov model (HMM). The short-time Fourier analysis of received signal strength employed to estimate speed. Based averaged power (local mean), pathless, using dynamic programming technique, predicts next state user. shows good ability predict mobility behavior area with...

The previously proposed first-order perturbation-based algorithm and linear constrained least mean square (LMS) based for channel matrix singular value decomposition (SVD) in multiple - input output (MIMO) orthogonal frequency division multiplexing (OFDM) systems are evaluated compared this paper from orthogonality, signal to noise plus interference ratio (SINR) bit error rate (BER) view points. Due approximations made the reduce its complexity, studies show that estimates of right left...