Nima Sarmadi

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A new blind channel estimation technique for multiple-input multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) systems is proposed. It estimates the channel parameters in the time domain jointly for all subcarriers instead of doing this in the frequency domain independently for each subcarrier. This results in a substantially improved(More)
In this paper, a new blind channel estimator for multiple-input mUltiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) systems is proposed. Based on the properties of the underlying orthogonal space-time block code (OSTBC), a novel subspace model is devised. The proposed tech­ nique consists in a closed-form approach in which the channels(More)
A new blind channel estimation approach for orthogonally coded multiple-input multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) systems is proposed. The main idea of our technique is, using specific properties of the orthogonal space-time block codes (OSTBCs), to estimate the finite impulse response (FIR) channel parameters in the time(More)
We consider blind channel estimation in multiple-input multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) systems with orthogonal space-time block code (OSTBC).We introduce a novel weighted covariance matrix of the received data which exploits all redundancies contained in the code. Based on the orthogonality properties of OSTBCs, we(More)
We propose a novel semi-blind tensor-based MIMO channel estimation scheme that employs orthogonal space-time block codes and per-antenna power loading at the transmitter. Our scheme eliminates the unknown transmit codewords and constructs a tensor model that contains the channel coefficients by performing post-processing at the receiver. Then, the channel(More)
In this paper, a new semiblind spectrally efficient channel estimation method is presented for fast fading orthogonally coded multiple-input multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) systems. The proposed method benefits from both the available training symbols inserted in the data frame structure of wireless standards as LTE(More)
In this paper, the problem of blind subspace-based channel estimation in multiple-input multiple-output (MIMO) systems under orthogonal space-time block coded (OSTBC) transmission is investigated. We introduce a virtual snapshot model in which the redundancies in the OSTBC are exploited to augment the received data. We show that the vector of true channel(More)
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