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1

Outage Analysis and Power Allocation for Space-time Block Coded Two-way Relaying

Yıldız M., Aygölü Ü.

Advances in Electronics and Telecommunications

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2013

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Vol. 3, no. 5

25--31

EN

In this paper, we consider the two-way relay channel (TWRC) over which communication is performed using spacetime block codes (STBC) with physical-layer network coding (PNC) protocol. The three-node two-way relaying (TWR) model consists of two end nodes (sources) simultaneously communicating with each other over a relay node where each node is equipped with two antennas and uses Alamouti’s STBC to provide diversity. We consider non-reciprocal channels where fading channel coefficients are independent for opposite directions of the same link. We first derive closed form expressions for the outage probability of the STBC-TWR system and uncoded TWRC assuming equal transmit power at each node and decode-and-forward (DF) strategy at the relay. We show that the STBC-TWR system significantly improves the uncoded TWRC outage performance. Then, to further improve the performance, we propose an optimal ower allocation in TWR scheme employing Alamouti’s STBC and PNC protocol. The optimal power allocation is obtained by maximizing the sum-rate under the total power constraint. We show that the optimal power allocation considerably improves the outage performance as well as the sum-rate compared to the equal-power case.

2

Metody transmisji w systemach wieloantenowych

Bronk K., Lipka A.

Zeszyty Naukowe Wydziału ETI Politechniki Gdańskiej. Technologie Informacyjne

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2007

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T. 14

753-760

PL

Niniejszy artykuł prezentuje zagadnienia związane z metodami transmisji wykorzystywanymi w systemach wieloantenowych MIMO (Multiple Input Multiple Output). W części wprowadzającej zaprezentowana zostanie kon-cepcja systemów wieloantenowych, ze szczególnym uwzględnieniem korzyści wynikających z ich implementacji. W kolejnych dwóch rozdziałach omówione będą dwie główne techniki transmisji, tj. kodowanie przestrzenno-czasowe (np. kodowanie Alamoutiego) oraz multipleksacja przestrzenna (BLAST). Zaprezentowane zostaną algorytmy, problemy oraz zalety każdej z metod. Ostatnia część artykułu stanowić będzie podsumowanie całości.

EN

Multiple antenna technique is arguably the most promising one in contemporary radiocommunications, with respect to both achievable data rates and overall system quality. In the first part of this article, the basic concept of multiple antenna systems (often referred to as MIMO systems) is briefly outlined. After that, in the main part of the text, the most common methods of transmission in such systems, i.e. spatial multiplexing and space-time coding, are described. We point out aspects referring to the relevant signal processing, as well as merits and draw-backs of each of the presented techniques. The last part is a conclusion.

3

An overview of Multiple-Input Multiple-Output (MIMO) systems

Bronk K., Lipka A., Katulski R. J., Stefański J.

Electronics and Telecommunications Quarterly

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2007

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Vol. 53, No 3

273-289

EN

In this article, a novel multiple-input multiple-output (MIMO) technology is presented. MIMO is a technique that gives the opportunity to achieve very high data rates in radio networks, thanks to utilizing numerous spatial channels, resulting from the use of many antennas on one or both sides of the radio link. In the first part of this article, we describe the basic facts referring to MIMO, including the major benefits from using this technology (out of which diversity and multiplexing gains are arguably the most significant). After that, the mathematical background of MIMO is briefly outlined. The subsequent part refers to one of the most significant issues connected with multipl-antenna systems, that is the channel capacity. Employing MIMO allows to increase this capacity and consequently to boost transmission rate. Basic definitions and formulas for capacity in different cases are provided. The next part explains two most common methods of transmission, i.e.: spatial multiplexing and space-time coding. Finally, in the last part we summarize and conclude the article.

4

Exact pairwise error probability analysis of space-time codes in spatially correlated fading channels

Lamahewa T. A., Kimon M. K., Abhayapala T. D., Kennedy R. A.

Journal of Telecommunications and Information Technology

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2006

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nr 1

60-68

EN

In this paper, we derive an analytical expression for the exact pairwise error probability (PEP) of a space-time coded system operating over a spatially correlated slow fading channel using a moment-generating function-based approach. This analytical PEP expression is more realistic than previously published exact-PEP expressions as it fully accounts for antenna spacing, antenna geometries (uniform linear array, uniform grid array, uniform circular array, etc.) and scattering models (uniform, Gaussian, Laplacian, Von-Mises, etc.). Inclusion of spatial information provides valuable insights into the physical factors determining the performance of a space-time code. We demonstrate the strength of our new analytical PEP expression by evaluating the performance of two space-time trellis codes proposed in the literature for different spatial scenarios.

5

Kodowanie przestrzenno-czasowe jako podstawowy element warstwy fizycznej systemów bezprzewodowych nowej generacji

Wódczak M.

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2003

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nr 2-3

87-91

PL

Przedstawiono kodowanie przestrzenno-czasowe jako nowy sposób transmisji sygnałów w kanałach radiowych. Omawia również możliwość zwiększania przepustowości kanału radiowego przez wykorzystanie matryc antenowych w nadajniku i odbiorniku.

EN

The article presents the space-time coding as a new approach to signals transmission over radio channels. It also discusses the possibility of radio channel capacity increase with the use of antenna arrays in transmitter and receiver.