Arama Sonuçları

Listeleniyor 1 - 3 / 3
  • Yayın
    A sequential Monte Carlo method for blind phase noise estimation and data detection
    (IEEE, 2005) Panayırcı, Erdal; Çırpan, Hakan Ali; Moeneclaey, Marc
    In this paper, a computationally efficient algorithm is presented for blind phase noise estimation and data detection jointly, based on a sequential Monte Carlo method. The basic idea is to treat the transmitted symbols as " missing data" and draw samples sequentially of them based on the observed signal samples up to time t. This way, the Bayesian estimates of the phase noise and the incoming data are obtained through these samples, sequentially drawn, together with their importance weights. The proposed receiver structure is seen to be ideally suited for high-speed parallel implementation using VLSI technology.
  • Yayın
    Frequency selective fading channel estimation in OFDM systems using KL expansion
    (IEEE, 2005) Şenol, Habib; Çırpan, Hakan Ali; Panayırcı, Erdal
    This paper proposes a computationally efficient, linear minimum mean square error (MMSE) channel estimation algorithm based on KL series expansion for OFDM systems. Based on such expansion, no matrix inversion is required in the proposed MMSE estimator. Moreover, truncation in the linear expansion of channel is achieved by exploiting the optimal truncation property of the KL expansion resulting in a smaller computational load on the estimation algorithm. The performance of the proposed approach is studied through analytical and experimental results. We provide performance analysis results studying the influence of the effect of SNR and correlation mismatch on the estimator performance. Simulation results confirm our theoretical results and illustrate that the proposed algorithm is capable of tracking fast fading and improving performance.
  • Yayın
    Improved microphone array design with statistical speaker verification
    (Elsevier Ltd, 2021-04) Demir, Kadir Erdem; Eskil, Mustafa Taner
    Conventional microphone array implementations aim to lock onto a source with given location and if required, tracking it. It is a challenge to identify the intended source when the location of the source is unknown and interference exists in the same environment. In this study we combine speaker verification and microphone array processing techniques to localize and maximize gain on the intended speaker under the assumption of open acoustic field. We exploit the steering capability of the microphone array for more accurate speaker verification. Our first contribution is a new N-Gram based and computationally efficient feature for detecting an intended speaker. When the source and interference are localized, microphone array can be tuned further to reduce noise and increase the gain. Our second contribution is this integrated algorithm for speaker verification and localization. In the context of this study we developed SharpEar, an open source environment that simulates propagation of sound emanating from multiple sources. Our third and last contribution is this simulation environment, which is open source and available to researchers of the field.