The work presented here addresses the problem of detecting a target in passive bistatic radar (PBR) presence interference signals, including receiver noise, direct signal, multipath/clutter echoes, and interfering targets. To this end, after outlining model detection surveillance channel as composite hypothesis test, generalized likelihood ratio test (GLRT) is derived. Its performance expressed closed forms for both interference-alone case, probability false alarm, signal-plus-interference...

FM-based passive bistatic radars (PBRs) exploiting a single broadcasted channel suffer from time-varying detection performance due to the program content of transmitted signal as well propagation condition that channel. To circumvent this matter, it is viable idea exploit multiple channels transmitter for detection. In case, we formulate problem detecting target in presence interference signals such receiver noise, direct signal, multipath/clutter echoes and interfering targets composite...

We propose computationally inexpensive and efficient solutions for signal activity detection of phase-shift keying (PSK) signals in additive white Gaussian noise. consider the complex amplitude as well information sequence unknown parameters. In addition, noise variance is assumed unknown. derive generalized likelihood ratio test (GLRT) suggest a implementation thereof. Furthermore, we develop new detector binary PSK signals, which will refer to energy detector. To evaluate performance these...

This paper examines the problem of suppressing dynamic clutter and multitarget detection in a digital video broadcasting-terrestrial (DVB-T)-based passive bistatic radar (PBR). A two-step low-complexity suppression method is presented to attenuate nonstationary multipath/clutter multiple-frequency network. In first step, we estimate multipath signals, as orthogonal frequency-division multiplexing channel coefficients, symbolwise approach. The variation signal tracked, using complex...

We propose computationally inexpensive and efficient solutions for signal activity detection of phase-shift keying (PSK) signals in additive white Gaussian noise. consider the complex amplitude signal, as well information sequence, unknown parameters. In addition, noise variance is assumed unknown. derive generalized likelihood ratio test (GLRT) suggest a implementation thereof. Furthermore, we develop new detector binary PSK signals, which will refer to energy detector. To evaluate...

We propose a computationally efficient algorithm for detection of multiple signals that also gives rough estimation their direction arrivals (DOAs). The narrowband received from uniform linear array are first filtered by set orthogonal filters, e.g., fast Fourier transformation, in order to separate the sources into spatial intervals. This transformation converts complicated multihypothesis problem source and localization binary hypothesis testing problems. For an additive white Gaussian...

Spectrum sensing is an essential capability that allows the cognitive radios (CRs) to detect spectral holes and opportunistically use underutilised frequency bands without causing deleterious interference primary users. In this study authors address two cooperative wideband spectrum techniques for frequency-selective frequency-non-selective fading channels in which user signals are detected over multiple bands. The signals, indices number of occupied subbands, characteristics noise variance...

In this letter, we develop a computationally efficient algorithm for the Maximum Likelihood (ML) sequences estimation (MLSE) of an M-ary Phase Shift keying ( <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">M</i> -PSK) signal transmitted over frequency non-selective slow fading channel with unknown complex amplitude and variance additive white Gaussian noise. The proposed also provides ML estimates noise that are critical in activity detection...

The adaptive radar detection of a point target in the presence signal-dependent interference, also known as system-dependent clutter, is addressed this paper. Here, signal assumed to be an intra-pulse modulated waveform and surrounded by both range frequency spectrum domains. In clutter-dominant situation, problem studied under wide-sense stationary (WSS) non-stationary Gaussian interference processes two closed-form detectors, respectively named WSS-Rao NS-Rao are derived. Both analytically...

This article deals with the problem of target detection in a passive multiple-input multiple-output (MIMO) radar network involving noncooperative illuminators opportunity (IOs) and geographically dispersed multichannel receivers. The signal model considers direct-path interference (DPI). We employ Rao test to solve derive closed-form detector. Then, by considering properties ambiguity functions most IO waveforms, an approximated version detector simpler form is derived. Two detectors case...

Although zero-forcing (ZF) detection is well-known for its low computational complexity in multiple-input multiple-output (MIMO) communication systems, it suffers from significantly poor performance. The sphere decoder (SD) method, on the other hand, achieves maximum likelihood (ML) performance yet imposes a high complexity. We propose low-complexity scheme, concatenated with SD which verifies reliability of ZF equalized observations via some predefined regions and thresholds obtained by...

The authors propose invariant tests for the detection of a complex signal with unknown constant amplitude and phase variation in additive white Gaussian noise (AWGN). show that this problem, uniformly most powerful (UMPI) detector does exist only if number samples N is two. For more than two N≥3, derive (MPI) known signal-to-noise ratio (SNR) use its performance as upper bound benchmark any test. In addition, generalised likelihood (GLR) evaluate against MPI bound. This very simple...

In this study, the authors study modulation classification of linearly modulated signals including amplitude shift keying (ASK), phase (PSK) and quadrature (QAM) signals. The consider an unknown frequency non-selective slowly fading channel with variance additive white Gaussian noise. treat problem as a multi-hypotheses test which is invariant under complex scale. such case, objective to find uniformly most powerful (UMP) in class decisions. However, out that UMPI does not exist; instead,...

A key technology in Cognitive Radio (CR) is spectrum sensing that senses the and reports available vacant channels. However, due to some effects such as fading or shadowing, an individual sensor may not be able reliably detect existence of a Primary User (PU). Cooperative proposed solve problem, uses distributed detection system overcome severe decadent received signal strength at locations network. This paper considers performance Neyman-Pearson (N-P) consisting N sensors fusion center,...

We propose a computationally non-expensive and powerful modulation classifier (MC) in order to determine the number of constellation points phase shift keying (PSK) signal additive white Gaussian noise (AWGN). consider complex amplitude as well information sequence unknown parameters. In contrast existing literature, we assume that variance is also unknown. A new MC algorithm introduced based on generalized likelihood ratio test (GLRT) assuming deterministic show GLRT solution does not...

A generalised modified multimodulus cost function for blind equalisation in digital communication systems is introduced. This generalisation achieved by dividing the complex plane of modulated signals into several disjoint regions where have different constant modulus. Then an adaptive learning algorithm that employs pseudo Newton method presented and based on predefined its corresponding steady-state mean square error (MSE) derived. Also, number evaluated so minimum MSE achieved. Here it...

The high resolution of the digital video broadcasting terrestrial (DVB‐T) signals leads to a dramatically large number observation samples in an integration time DVB‐T‐based passive radar. Hence, because computational complexity (CC), applying extensive cancellation algorithm and generalised likelihood ratio (GLR) detector seems be impractical radars. In this study, authors derive reduced GLR for radar presence clutter, interfering targets noise. proposed employs split received signal reduce...

Due to the computational complexity of maximum-likelihood signal decoding, equalizers with less are considered in literature. Employing zero forcing (ZF) equalizer, zero-padded orthogonal frequency-division multiplexing (ZP-OFDM) is capable benefiting maximum available multipath diversity inverting a matrix size data block length, which incurs an extra implementation cost relative fast Fourier transform-based OFDM decoder. In this paper, based on ZP-OFDM encoding scheme, we propose two-stage...

In this paper, we investigate the detection of a band-limited signal with unknown central frequency, exact bandwidth and spectrum in white Gaussian noise variance. We propose practically implementable Generalized Likelihood Ratio (GLR) detector these parameters verify its performance through some simulation examples. Furthermore, order to evaluate detector, derive Most Powerful Invariant (MPI) case known partial Signal Noise Ratios (SNRs), i.e., where SNR different Discrete Fourier Transform...

The authors propose a computationally efficient spectrum sensing solution for an orthogonal frequency division multiplexing (OFDM) signal in frequency-selective fading channel with additive white Gaussian noise (AWGN). authors' assumption is that the data symbols, coefficients and variance are all unknown. nature of problem leads them to find invariant detector. optimum one uniformly most powerful (UMPI); their effort shows this test does not exist, as final decision statistic depends on...

In this paper, we address the radar adaptive detection problem in case of multiple fluctuating targets with unknown parameters. The parameters are: number and location targets, amplitude phase received signals, Doppler frequency slowly target signal vectors rapid-fluctuating statistical characteristics noise clutter. We extract generalised likelihood ratio test (GLRT) Gaussian interference covariance matrix. Owing to high computational complexity these detectors when probable is large,...