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  • Journal article
    Gao Z, Dai L, Dai W, Shim B, Wang Zet al., 2016,

    Structured compressive sensing-based spatio-temporal joint channel estimation for FDD massive MIMO

    , IEEE Transactions on Communications, Vol: 64, Pages: 601-617, ISSN: 0090-6778

    Massive MIMO is a promising technique for future 5G communications due to its high spectrum and energy efficiency. To realize its potential performance gain, accurate channel estimation is essential. However, due to massive number of antennas at the base station (BS), the pilot overhead required by conventional channel estimation schemes will be unaffordable, especially for frequency division duplex (FDD) massive MIMO. To overcome this problem, we propose a structured compressive sensing (SCS)-based spatio-temporal joint channel estimation scheme to reduce the required pilot overhead, whereby the spatio-temporal common sparsity of delay-domain MIMO channels is leveraged. Particularly, we first propose the nonorthogonal pilots at the BS under the framework of CS theory to reduce the required pilot overhead. Then, an adaptive structured subspace pursuit (ASSP) algorithm at the user is proposed to jointly estimate channels associated with multiple OFDM symbols from the limited number of pilots, whereby the spatio-temporal common sparsity of MIMO channels is exploited to improve the channel estimation accuracy. Moreover, by exploiting the temporal channel correlation, we propose a space-time adaptive pilot scheme to further reduce the pilot overhead. Additionally, we discuss the proposed channel estimation scheme in multicell scenario. Simulation results demonstrate that the proposed scheme can accurately estimate channels with the reduced pilot overhead, and it is capable of approaching the optimal oracle least squares estimator.
  • Journal article
    Tonoyan Y, Looney D, Mandic DP, Van Hulle MMet al., 2016,

    Discriminating multiple emotional states from EEG using a data-adaptive, multiscale information-theoretic approach

    , International Journal of Neural Systems, Vol: 26, ISSN: 1793-6462

    A multivariate sample entropy metric of signal complexity is applied to EEG data recorded when subjects were viewing four prior-labeled emotion-inducing video clips from a publically available, validated database. Besides emotion category labels, the video clips also came with arousal scores. Our subjects were also asked to provide their own emotion labels. In total 30 subjects with age range 19–70 years participated in our study. Rather than relying on predefined frequency bands, we estimate multivariate sample entropy over multiple data-driven scales using the multivariate empirical mode decomposition (MEMD) technique and show that in this way we can discriminate between five self-reported emotions (p<0.05p<0.05). These results could not be obtained by analyzing the relation between arousal scores and video clips, signal complexity and arousal scores, and self-reported emotions and traditional power spectral densities and their hemispheric asymmetries in the theta, alpha, beta, and gamma frequency bands. This shows that multivariate, multiscale sample entropy is a promising technique to discriminate multiple emotional states from EEG recordings.
  • Journal article
    Yueruer O, Liu CH, Sheng Z, Leung VCM, Moreno W, Leung KKet al., 2016,

    Context-Awareness for Mobile Sensing: A Survey and Future Directions

    , IEEE Communications Surveys and Tutorials, Vol: 18, Pages: 68-93, ISSN: 1553-877X

    The evolution of smartphones together with increasingcomputational power has empowered developers to createinnovative context-aware applications for recognizing user-relatedsocial and cognitive activities in any situation and at any location.The existence and awareness of the context provide the capabilityof being conscious of physical environments or situations aroundmobile device users. This allows network services to respondproactively and intelligently based on such awareness. The keyidea behind context-aware applications is to encourage users tocollect, analyze, and share local sensory knowledge in the purposefor a large-scale community use by creating a smart network. Thedesired network is capable of making autonomous logical decisionsto actuate environmental objects and also assist individuals.However, many open challenges remain, which are mostly arisenbecause the middleware services provided in mobile devices havelimited resources in terms of power, memory, and bandwidth.Thus, it becomes critically important to study how the drawbackscan be elaborated and resolved and, at the same time, betterunderstand the opportunities for the research community to contributeto the context-awareness. To this end, this paper surveysthe literature over the period of 1991–2014 from the emergingconcepts to applications of context-awareness in mobile platformsby providing up-to-date research and future research directions.Moreover, it points out the challenges faced in this regard andenlightens them by proposing possible solutions.
  • Conference paper
    Doire CSJ, Brookes DM, Naylor PA, De Sena E, van Waterschoot T, Jensen SHJet al., 2016,

    Acoustic Environment Control: Implementation of a Reverberation Enhancement System

    , AES 60th International Conference: DREAMS (Dereverberation and Reverberation of Audio, Music, and Speech)

    Reverberation enhancement systems allow the active control of the acoustic environment. They are subject to instability issues due to acoustic feedback, and are often installed permanently in large halls, sometimes at great cost. In this paper, we explore the possibility of implementing a cost-effective reverberation enhancement system to control the acoustics of typical rooms using a combination of spatial filtering, automatic calibration, adaptive notch filters, howling detection and manual adjustments. The effectiveness of the system is then tested inside a small soundproof booth.
  • Journal article
    Rezaee M, Schreier PJ, Guillaud M, Clerckx Bet al., 2016,

    A Unified Scheme to Achieve the Degrees-of-Freedom Region of the MIMO Interference Channel With Delayed Channel State Information

    , IEEE Transactions on Communications, Vol: 64, Pages: 1068-1082, ISSN: 1558-0857

    In interference channels (ICs), channel state information (CSI) can be utilized to design transmit signals that are optimally adapted to the state of the channels. This requires feeding CSI back to the transmitters. The CSI available at the transmitters (CSIT) is usually degraded, due to the limited capacity of the feedback link and the delays involved in the channel estimation and feedback. We discuss the scenario of fast fading and delayed CSIT, which is highly relevant in mobile environments with short channel coherence times. We consider the two-user multiple-input-multiple-output (MIMO) IC where the transmitters are provided with delayed CSIT. The DoF region for this channel was characterized by Vaze and Varanasi. We devise a simple and intuitive achievable scheme, which has a unified structure for different antenna configurations. We show that the proposed scheme also achieves the DoF region of the two-user MIMO broadcast channel (BC). In the IC, our scheme does not require the knowledge of direct channels at the transmitters. Moreover, we show that the amount of feedback can be further reduced by exploiting the invariances of the problem. Our approach can be helpful when analyzing more complicated networks.
  • Journal article
    Parada PP, Sharma D, Lainez J, Barreda D, van Waterschoot T, Naylor PAet al., 2016,

    A single-channel non-intrusive C50 estimator correlated with speech recognition performance

    , IEEE/ACM Transactions on Audio, Speech and Language Processing, Vol: 24, Pages: 719-732, ISSN: 2329-9304
  • Journal article
    Zhao X, Jiang Y, Stathaki T, Zhang Het al., 2016,

    Gait recognition method for arbitrary straight walking paths using appearance conversion machine

    , Neurocomputing, Vol: 173, Pages: 530-540, ISSN: 0925-2312

    We investigate the problem of multi-view human gait recognition along any straight walking paths. It is observed that the gait appearance changes as the view changes while certain amount of correlated information exists among different views. Taking advantage of that type of correlation, a multi-view gait recognition method is proposed in this paper. First, we estimate the viewing angle of the monitor equipment in terms of the probe subject. To this end, our method considers this as a classification problem, where the classification signals are the viewing angles, and the classification features are the elements of the transformation matrix that is estimated by the Transformation Invariant Low-Rank Texture (TILT) algorithm. Then, the gallery gait appearances are converted to the view of the probe subject using the proposed Appearance Conversion Machine (ACM), where the gait features of the spatially neighbouring pixels of the gait feature are considered as the correlated information of the two views. In the end, a similarity measurement is applied on the converted gait appearance and the testing gait appearance. Experiments on the CASIA-B multi-view gait database show that the proposed gait recognition method outperforms the state-of-the-art under most views.
  • Conference paper
    Evers C, Moore A, Naylor P, 2016,

    Towards Informative Path Planning for Acoustic SLAM

    , DAGA 2016

    Acoustic scene mapping is a challenging task as microphonearrays can often localize sound sources only interms of their directions. Spatial diversity can be exploitedconstructively to infer source-sensor range whenusing microphone arrays installed on moving platforms,such as robots. As the absolute location of a moving robotis often unknown in practice, Acoustic SimultaneousLocalization And Mapping (a-SLAM) is required in orderto localize the moving robot’s positions and jointlymap the sound sources. Using a novel a-SLAM approach,this paper investigates the impact of the choice of robotpaths on source mapping accuracy. Simulation results demonstratethat a-SLAM performance can be improved byinformatively planning robot paths.
  • Journal article
    Rassouli B, Hao C, Clerckx B, 2016,

    DoF analysis of the MIMO broadcast channel with alternating/hybrid CSIT

    , IEEE Transactions on Information Theory, Vol: 62, Pages: 1312-1325, ISSN: 1557-9654

    We consider a K-user multiple-input singleoutput (MISO) broadcast channel (BC) where the channel state information (CSI) of user i(i = 1,2, .. ., K) may be instantaneously perfect (P), delayed (D), or not known (N) at the transmitter with probabilities λPi, λDi, and λNi, respectively. In this setting, according to the three possible CSI at the transmitter (CSIT) for each user, knowledge of the joint CSIT of the K users could have at most 3K states. In this paper, given the marginal probabilities of CSIT (i.e., λPi, λDi, and λNi), we derive an outer bound for the degrees of freedom (DoF) region of the K-user MISO BC. Subsequently, we tighten this outer bound by considering a set of inequalities that capture some of the 3K states of the joint CSIT. One of the consequences of this set of inequalities is that for K ≥ 3, it is shown that the DoF region is not completely characterized by the marginal probabilities in contrast to the two-user case. Afterwards, the tightness of these bounds is investigated through the discussion on the achievability. Finally, a two user multiple-input multipleoutput BC having CSIT among P and N is considered in which an outer bound for the DoF region is provided, and it is shown that in some scenarios, it is tight.
  • Journal article
    Jaksic V, Mandic DP, Ryan K, Basu B, Pakrashi Vet al., 2016,

    A comprehensive study of the delay vector variance method for quantification of nonlinearity in dynamical systems

    , Royal Society Open Science, Vol: 3, ISSN: 2054-5703

    Although vibration monitoring is a popular method to monitor and assess dynamic structures, quantification of linearity or nonlinearity of the dynamic responses remains a challenging problem. We investigate the delay vector variance (DVV) method in this regard in a comprehensive manner to establish the degree to which a change in signal nonlinearity can be related to system nonlinearity and how a change in system parameters affects the nonlinearity in the dynamic response of the system. A wide range of theoretical situations are considered in this regard using a single degree of freedom (SDOF) system to obtain numerical benchmarks. A number of experiments are then carried out using a physical SDOF model in the laboratory. Finally, a composite wind turbine blade is tested for different excitations and the dynamic responses are measured at a number of points to extend the investigation to continuum structures. The dynamic responses were measured using accelerometers, strain gauges and a Laser Doppler vibrometer. This comprehensive study creates a numerical and experimental benchmark for structurally dynamical systems where output-only information is typically available, especially in the context of DVV. The study also allows for comparative analysis between different systems driven by the similar input.
  • Journal article
    Song C, Ling C, 2016,

    On the Diversity of Linear Transceivers in MIMO AF Relaying Systems

    , IEEE Transactions on Information Theory, Vol: 62, Pages: 272-289, ISSN: 1557-9654

    In this paper, we provide a comprehensive survey on designs and analyses of various relay-destination transceiving schemes, such as zero-forcing (ZF), minimum mean squared error (MMSE), and maximum information rate (MIR) criteria, in multiple-input multiple-output (MIMO) amplify-and-forward (AF) relaying systems. In the first part of the paper, we suggest a new framework for the transceiver designs utilizing a decomposable property of the error covariance matrix to give a general insight on the system and make the analysis more tractable. Then, in the second part of the paper, we provide an in-depth analysis on their diversity performance. Our analysis embraces two different scenarios, namely, the diversity-multiplexing tradeoff (DMT) and the diversity-rate tradeoff (DRT). First, we derive compact closed-form expressions for the DMT through tight upper and lower bounds. Then, we observe that while our DMT analysis accurately predicts performance of the ZF and MIR schemes, the MMSE-based designs exhibit a complicated rate-dependent behavior and, thus, are very unpredictable via DMT for finite rate cases. Thus, second, we highlight this interesting observation and characterize the diversity of the MMSE schemes at all finite rates. This leads to closed-form expressions for the DRT which reveals relationship between diversity, spectral efficiency, and the number of antennas at each node. The DRT analysis compliments our work on DMT, and thus, the paper provides a complete understanding on the diversity of MIMO AF relaying systems.
  • Journal article
    Zhao X, Jiang Y, Stathaki T, 2016,

    A novel low false alarm rate pedestrian detection framework based on single depth images

    , Image and Vision Computing, Vol: 45, Pages: 11-21, ISSN: 1872-8138

    Pedestrian detection is an important image understanding problem with many potential applications. There has been little success in creating an algorithm which exhibits a high detection rate while keeping the false alarm in a relatively low rate. This paper presents a method designed to resolve this problem. The proposed method uses the Kinect or any similar type of sensors which facilitate the extraction of a distinct foreground. Then potential regions, which are candidates for the presence of human(s), are detected by employing the widely used Histogram of Oriented Gradients (HOG) technique, which performs well in terms of good detection rates but suffers from significantly high false alarm rates. Our method applies a sequence of operations to eliminate the false alarms produced by the HOG detector based on investigating the fine details of local shape information. Local shape information can be identified by efficient utilization of the edge points which, in this work, are used to formulate the so called Shape Context (SC) model. The proposed detection framework is divided in four sequential stages, with each stage aiming at refining the detection results of the previous stage. In addition, our approach employs a pre-evaluation stage to pre-screen and restrict further detection results. Extensive experimental results on the dataset created by the authors, involves 673 images collected from 11 different scenes, demonstrate that the proposed method eliminates a large percentage of the false alarms produced by the HOG pedestrian detector.
  • Conference paper
    Huang Y, Clerckx B, 2016,

    Waveform Optimization for Large-Scale Multi-Antenna Multi-Sine Wireless Power Transfer

    , 17th IEEE International Workshop on Signal Processing Advances in Wireless Communications (SPAWC), Publisher: IEEE, ISSN: 2325-3789
  • Conference paper
    Lee H, Lee K-J, Kim H, Clerckx B, Lee Iet al., 2016,

    Resource Allocation Techniques for Wireless Powered Communication Networks

    , IEEE International Conference on Communications (ICC), Publisher: IEEE, ISSN: 1550-3607
  • Conference paper
    Javed HA, Moore AH, Naylor PA, 2016,

    SPHERICAL HARMONIC RAKE RECEIVERS FOR DEREVERBERATION

    , 15th International Workshop on Acoustic Signal Enhancement (IWAENC), Publisher: IEEE
  • Conference paper
    Zhang W, Naylor PA, 2016,

    AN ITERATIVE METHOD FOR EQUALIZATION OF MULTICHANNEL ACOUSTIC SYSTEMS ROBUST TO SYSTEM IDENTIFICATION ERRORS

    , 15th International Workshop on Acoustic Signal Enhancement (IWAENC), Publisher: IEEE
  • Conference paper
    Liu W, Ling C, 2016,

    LDA-Lattice Aided Network Coding for Two-Way Relay

    , SAI Computing Conference (SAI), Publisher: IEEE, Pages: 610-614
  • Conference paper
    Hemakom A, Goverdovsky V, Aufegger L, Mandic DPet al., 2016,

    QUANTIFYING COOPERATION IN CHOIR SINGING: RESPIRATORY AND CARDIAC SYNCHRONISATION

    , 41st IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), Publisher: IEEE, Pages: 719-723, ISSN: 1520-6149
  • Conference paper
    Enshaeifar S, Took CC, Sanei S, Mandic DPet al., 2016,

    NOVEL QUATERNION MATRIX FACTORISATIONS

    , 41st IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), Publisher: IEEE, Pages: 3946-3950, ISSN: 1520-6149
  • Conference paper
    Douglas SC, Mandic DP, 2016,

    STABILITY ANALYSIS OF THE LEAST-MEAN-MAGNITUDE-PHASE ALGORITHM

    , 41st IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), Publisher: IEEE, Pages: 4935-4939, ISSN: 1520-6149
  • Conference paper
    Xiang M, Kanna S, Douglas SC, Mandic DPet al., 2016,

    PERFORMANCE ADVANTAGE OF QUATERNION WIDELY LINEAR ESTIMATION: AN APPROXIMATE UNCORRELATING TRANSFORM APPROACH

    , 41st IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), Publisher: IEEE, Pages: 4348-4352, ISSN: 1520-6149
  • Conference paper
    Kotzagiannidis MS, Dragotti PL, 2016,

    THE GRAPH FRI FRAMEWORK-SPLINE WAVELET THEORY AND SAMPLING ON CIRCULANT GRAPHS

    , 41st IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), Publisher: IEEE, Pages: 6375-6379, ISSN: 1520-6149
  • Conference paper
    Onativia J, Lu YM, Dragotti PL, 2016,

    PROSPARSE DENOISE: PRONY'S BASED SPARSE PATTERN RECOVERY IN THE PRESENCE OF NOISE

    , 41st IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), Publisher: IEEE, Pages: 4084-4088, ISSN: 1520-6149
  • Conference paper
    Zahedi A, Ostergaard J, Jensen SH, Naylor P, Bech Set al., 2016,

    On Perceptual Audio Compression with Side Information at the Decoder

    , Data Compression Conference (DCC), Publisher: IEEE, Pages: 456-465, ISSN: 1068-0314
  • Conference paper
    Cauchi B, Javed H, Gerkmann T, Doclo S, Goetze S, Naylor Pet al., 2016,

    PERCEPTUAL AND INSTRUMENTAL EVALUATION OF THE PERCEIVED LEVEL OF REVERBERATION

    , 41st IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), Publisher: IEEE, Pages: 629-633, ISSN: 1520-6149
  • Conference paper
    Zhang Z, Li H, Mandic D, 2016,

    Blind Source Separation and Artefact Cancellation for Single Channel Bioelectrical Signal

    , 13th IEEE International Conference on Wearable and Implantable Body Sensor Networks (BSN), Publisher: IEEE, Pages: 177-182, ISSN: 2376-8886
  • Conference paper
    Lyu S, Ling C, 2016,

    Sequential lattice reduction

    , 8th International Conference on Wireless Communications and Signal Processing (WCSP), Publisher: IEEE, ISSN: 2325-3746
  • Conference paper
    Liu L, Shi J, Ling C, 2016,

    Extracting Wyner's Common Randomness Using Polar Codes

    , 8th International Conference on Wireless Communications and Signal Processing (WCSP), Publisher: IEEE, ISSN: 2325-3746
  • Conference paper
    Wu X, Ling C, 2016,

    A Channel Coding Approach for Physical-Layer Authentication

    , 8th International Conference on Wireless Communications and Signal Processing (WCSP), Publisher: IEEE, ISSN: 2325-3746
  • Conference paper
    Maggioni M, Dragotti PL, 2016,

    Video Temporal Super-Resolution Using Nonlocal Registration and Self-Similarity

    , 18th IEEE International Workshop on Multimedia Signal Processing (MMSP), Publisher: IEEE, ISSN: 2163-3517

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