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1

Spatial Multiplexing in Random Wireless Networks

Stamatiou K., Proakis J. G., Zeidler J. R.

Advances in Electronics and Telecommunications

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2010

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Vol. 1, no. 1

5--12

EN

We consider a network of transmitters, each with a receiver at a fixed distance, and locations drawn independen tly according to a homogeneous Poisson Point Process (PPP). The transmitters and the receivers are equipped with multiple a ntennas. Under a channel model that includes Rayleigh fading and path-loss, and an outage model for packet successes, we examine the rformance of various spatial multiplexing techniques, namely zero-forcing (ZF), ZF with successive interference cancellation (ZF-SIC or VBLAST) and DBLAST. In each case, we determine the number of streams that maximizes the transmission capacity, defined as the maximum network throughput per unit area such that a constraint on the outage probability is satisfied. Numerical results showcase the benefit of DBLAS Tover ZF and VBLAST in terms of the transmission capacity. In all cases, the transmission capacity scales linearly in the number of antennas.

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.