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[...]... convolutional or spreading code signal-to-noise ratio at receive antenna and time instant k code average signal-to-noise ratio γ ¯ η matrix of MIMO channel at time instant k extended matrix of MIMO channel reduced matrix of MIMO channel submatrix of frequency selective MIMO channel corresponding to delay µ at time instant k channel coefficient between transmitter ξ and receiver ρ corresponding to delay µ... in a cellular network is accessed by NI inputs and NO outputs In this context, the term channel is not limited to the physical transmission Wireless CommunicationsoverMIMO Channels Volker K¨ hn u 2006 John Wiley & Sons, Ltd 2 INTRODUCTION TO DIGITAL COMMUNICATIONS 1 1 2 2 channel NI NO Figure 1.1 Principle of multiple access to a common channel medium, that is, the radio channel, but has a more... expected, all the mentioned access schemes can be combined The well-known Global System for Mobile (GSM) Communications and Digital Cellular System (DCS)1800 standards both combine Time division multiple access (TDMA) and FDMA In UMTS (Universal Mobile Telecommunications System) or IMT-2000 (International Mobile Communications) systems, CDMA is used in connection with TDMA and FDMA (Dahlman et al 1998; Ojanper¨... outage capacity is discussed The next section derives the capacity of multiple-input multiple-output (MIMO) systems in a general way without delivering specific results They are presented for CDMA and SDMA systems in Chapters 4 and 6 The chapter closes with a short summary on theoretic survey of multiuser communications Chapter 3: Forward Error Correction Coding The third chapter gives a short survey of... the combination of linear preprocessing and nonlinear interference cancellation based on the QL decomposition of the mixing matrix Chapter 6: Multiple Antenna Systems Chapter 6 covers several topics related to point-to-point communications with multiple antennas It starts with diversity concepts such as receive diversity and space-time coding Next, the principle of spatial multiplexing is explained... 6.4.4 Optimizing Linear Dispersion Codes 6.4.5 Detection of Linear Dispersion Codes 6.5 Information Theoretic Analysis 6.5.1 Uncorrelated MIMO Channels 6.5.2 Correlated MIMO Channels 6.6 Summary ... generating function of process X number of bits per symbol size of modulation alphabet nν [k] NI NO NR Ns NT Nu N0 additive noise at receive antenna ν and time instant k number of inputs of MIMO system number of outputs of MIMO system number of receive antennas spreading factor of CDMA system number of transmit antennas number of active users power spectral density of complex noise in equivalent baseband... inverse of matrix X scalar processes are written by calligraphic letters multivariate processes are written by underlined calligraphic letters 1 Introduction to Digital Communications This first chapter introduces some of the basics of digital communications that are needed in subsequent chapters Section 1.1 starts with a brief introduction of fundamental multiple access techniques and the general structure... Model 1.1.1 Introduction Vector channels, or multiple-input multiple-output (MIMO) channels, represent a very general description for a wide range of applications They incorporate SISO (Single-Input Single-Output), MISO (Multiple-Input Single-Output) and SIMO (Single-Input MultipleOutput) channels as special cases Often, MIMO channels are only associated with multiple antenna systems However, they... of services The frequency reuse factor in such cellular networks allows neighboring cells to operate at the same frequency, leading to a more efficient use of the resource frequency Moreover, this allows simpler soft handover compared to the ‘break before make’ strategy in global system for mobile communication (GSM) when mobile subscribers change the serving cell The main drawback of CDMA systems is . x0 y0 w0 h0" alt=""