Roald Otnes

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—We investigate turbo equalization, or iterative equalization and decoding, as a receiver technology for systems where data is protected by an error-correcting code, shuffled by an in-terleaver, and mapped onto a signal constellation for transmission over a frequency-selective channel with unknown time-varying channel impulse response. The focus is the(More)
— Low-complexity soft-in soft-out (SISO) equalizers based on time-varying linear filters and soft inter-symbol interference cancellation are known to be a viable alternative to the optimal trellis-based SISO equalizers when used in receivers based on iterative equalization and decoding. In particular, when the signal constellation is large and/or the(More)
—To combat the effect of intersymbol interference (ISI) while transmitting data over an ISI channel in a coded data transmission system, the impulse response of the channel is required. As part of the turbo equalization approach, which facilitates iterative equalization and decoding, we introduce a method to iteratively improve the quality of the estimate(More)
This is the authors' manuscript of the literature survey monograph " Underwater acoustic networking techniques " , published in the series " SpringerBriefs in Electrical and Computer Engineering ". The content is identical, but the published version has a much nicer layout, a handier format, and separate reference lists for each chapter. The authors have(More)
In this paper, we discuss the performance of different network protocols for RACUN, a European Defence Agency project with the objective of demonstrating ad hoc underwater networks for multiple purposes related to security. The RACUN network is designed for long-range communications over areas of large size, hence a very important role is played by the(More)
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