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Full-Text Articles in Engineering
Superimposed Signaling Inspired Channel Estimation In Full-Duplex Systems, Abbas Koohian, Hani Mehrpouyan, Ali A. Nasir, Salman Durrani, Steven D. Blostein
Superimposed Signaling Inspired Channel Estimation In Full-Duplex Systems, Abbas Koohian, Hani Mehrpouyan, Ali A. Nasir, Salman Durrani, Steven D. Blostein
Electrical and Computer Engineering Faculty Publications and Presentations
Residual self-interference (SI) cancellation in the digital baseband is an important problem in full-duplex (FD) communication systems. In this paper, we propose a new technique for estimating the SI and communication channels in a FD communication system, which is inspired from superimposed signaling. In our proposed technique, we add a constant real number to each constellation point of a conventional modulation constellation to yield asymmetric shifted modulation constellations with respect to the origin. We show mathematically that such constellations can be used for bandwidth efficient channel estimation without ambiguity. We propose an expectation maximization (EM) estimator for use with the …
Multi-Relay Communications In The Presence Of Phase Noise And Carrier Frequency Offsets, Omar H. Salim, Ali Arshad Nasir, Hani Mehrpouyan, Wei Xiang
Multi-Relay Communications In The Presence Of Phase Noise And Carrier Frequency Offsets, Omar H. Salim, Ali Arshad Nasir, Hani Mehrpouyan, Wei Xiang
Electrical and Computer Engineering Faculty Publications and Presentations
Impairments like time varying phase noise (PHN) and carrier frequency offset (CFO) result in loss of synchronization and poor performance of multi-relay communication systems. Joint estimation of these impairments is necessary in order to correctly decode the received signal at the destination. In this paper, we address spectrally-efficient multi-relay transmission scenarios where all the relays simultaneously communicate with the destination. We propose an iterative pilot-aided algorithm based on the expectation conditional maximization (ECM) for joint estimation of multipath channels, Wiener PHNs, and CFOs in decode-and-forward (DF) based multi-relay orthogonal frequency division multiplexing (OFDM) systems. Next, a new expression of the …
Channel Estimation, Carrier Recovery, And Data Detection In The Presence Of Phase Noise In Ofdm Relay Systems, Rui Wang, Hani Mehrpouyan, Meixia Tao, Yingbo Hua
Channel Estimation, Carrier Recovery, And Data Detection In The Presence Of Phase Noise In Ofdm Relay Systems, Rui Wang, Hani Mehrpouyan, Meixia Tao, Yingbo Hua
Electrical and Computer Engineering Faculty Publications and Presentations
Due to its time-varying nature, oscillator phase noise can significantly degrade the performance of channel estimation, carrier recovery, and data detection blocks in high-speed wireless communication systems. In this paper, we analyze joint channel, carrier frequency offset (CFO), and phase noise estimation plus data detection in orthogonal frequency division multiplexing (OFDM) relay systems. To achieve this goal, a detailed transmission framework involving both training and data symbols is presented. In the data transmission phase, a combtype OFDM symbol consisting of both pilots and data symbols is proposed to track phase noise over an OFDM frame. Next, a novel algorithm …
Timing And Carrier Synchronization In Wireless Communication Systems: A Survey And Classification Of Research In The Last 5 Years, Ali A. Nasir, Salman Durrani, Hani Mehrpouyan, Steven D. Blostein, Rodney A. Kennedy
Timing And Carrier Synchronization In Wireless Communication Systems: A Survey And Classification Of Research In The Last 5 Years, Ali A. Nasir, Salman Durrani, Hani Mehrpouyan, Steven D. Blostein, Rodney A. Kennedy
Electrical and Computer Engineering Faculty Publications and Presentations
Timing and carrier synchronization is a fundamental requirement for any wireless communication system to work properly. Timing synchronization is the process by which a receiver node determines the correct instants of time at which to sample the incoming signal. Carrier synchronization is the process by which a receiver adapts the frequency and phase of its local carrier oscillator with those of the received signal. In this paper, we survey the literature over the last 5 years (2010–2014) and present a comprehensive literature review and classification of the recent research progress in achieving timing and carrier synchronization in single-input single-output (SISO), …
Channel Estimation And Optimal Training Design For Correlated Mimo Two-Way Relay Systems In Colored Environment, Rui Wang, Meixia Tao, Hani Mehrpouyan, Yingbo Hua
Channel Estimation And Optimal Training Design For Correlated Mimo Two-Way Relay Systems In Colored Environment, Rui Wang, Meixia Tao, Hani Mehrpouyan, Yingbo Hua
Electrical and Computer Engineering Faculty Publications and Presentations
In this paper, while considering the impact of antenna correlation and the interference from neighboring users, we analyze channel estimation and training sequence design for multi-input multi-output (MIMO) two-way relay (TWR) systems. To this end, we propose to decompose the bidirectional transmission links into two phases, i.e., the multiple access (MAC) phase and the broadcasting (BC) phase. By considering the Kronecker-structured channel model, we derive the optimal linear minimum mean-square-error (LMMSE) channel estimators. The corresponding training designs for the MAC and BC phases are then formulated and solved to improve channel estimation accuracy. For the general scenario of training sequence …
Timing And Carrier Synchronization With Channel Estimation In Af Two-Way Relaying Networks, Ali A. Nasir, Hani Mehrpouyan, Salman Durrani, Steven D. Bolstein, Rodney A. Kennedy
Timing And Carrier Synchronization With Channel Estimation In Af Two-Way Relaying Networks, Ali A. Nasir, Hani Mehrpouyan, Salman Durrani, Steven D. Bolstein, Rodney A. Kennedy
Electrical and Computer Engineering Faculty Publications and Presentations
Two-way relaying networks (TWRNs) allow for more bandwidth efficient use of the available spectrum since they allow for simultaneous information exchange between two users with the assistance of an intermediate relay node. However, due to superposition of signals at the relay node, the received signal at the user terminals is affected by multiple impairments, i.e., channel gains, timing offsets, and carrier frequency offsets, that need to be jointly estimated and compensated. This paper presents the system model for amplify-and-forward (AF) TWRNs in the presence of multiple impairments and proposes least squares and differential evolution based algorithms for joint estimation …