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In this paper, we consider the channel estimation
problem in Millimeter wave (mmWave) wireless systems with
large antenna arrays. By exploiting the inherent sparse nature of
the mmWave channel, we develop a novel rate-adaptive channel
estimation (RACE) algorithm, which can adaptively adjust the
number of required channel measurements based on an expected
probability of estimation error (PEE).
This book examines the technologies underlying the compression and trans-
mission of digital video sequences over networking platforms. The incorporated
study covers a large spectrum of topics related to compressed video communica-
tions. It presents to readers a comprehensive and structured analysis of the issues
encountered in the transmission of compressed video streams over networking
environments.
Cellular communications is one of the fastest growing and most challenging telecom-
munication applications ever. Today, it represents a large and continuously increasing
percentage of all new telephone subscribers around the world. In the long term,
cellular digital technology may become the universal way of communication.
The wireless market has experienced a phenomenal growth since the first second-
generation (2G) digital cellular networks, based on global system for mobile
communications (GSM) technology, were introduced in the early 1990s. Since then,
GSM has become the dominant global 2G radio access standard. Almost 80% of today’s
new subscriptions take place in one of the more than 460 cellular networks that use
GSM technology. This growth has taken place simultaneously with the large experienced
expansion of access to the Internet and its related multimedia services.
In this paper we revisit hybrid analog-digital precoding systems with emphasis on their modelling
and radio-frequency (RF) losses, to realistically evaluate their benefits in 5G system implementations.
For this, we decompose the analog beamforming networks (ABFN) as a bank of commonly used RF
components and formulate realistic model constraints based on their S-parameters. Specifically, we
concentrate on fully-connected ABFN (FC-ABFN) and Butler networks for implementing the discrete
Fourier transform (DFT) in the RF domain. The results presented in this paper reveal that the performance
and energy efficiency of hybrid precoding systems are severely affected, once practical factors are
considered in the overall design. In this context, we also show that Butler RF networks are capable of
providing better performances than FC-ABFN for systems with a large number of RF chains.
When we started thinking about writing the first edition of this book a few years ago, we had been
working together for more than five years on the borderline between propagation and signal processing.
Therefore, it is not surprising that this book deals with propagation models and design tools for MIMO
wireless communications. Yet, this book should constitute more than a simple combination of these
two domains. It hopefully conveys our integrated understanding of MIMO, which results from endless
controversial discussions on various multi-antenna related issues, as well as various interactions with
numerous colleagues. Obviously, this area of technology is so large that it is beyond our aim to cover all
aspects in details. Rather, our goal is to provide researchers, R&D engineers and graduate students with
a comprehensive coverage of radio propagation models and space–time signal processing techniques
for multi-antenna, multi-user and multi-cell networks.
When we started thinking about writing this book, we had been working together for more
than five years on the borderline between propagation and signal processing.Therefore, it
is not surprising that this book deals with propagation models and design tools for MIMO
wirelesscommunications.Yet, thisbookshouldconstitutemorethanasimplecombination
of these two domains. It hopefully conveys our integrated understanding of MIMO, which
results from endless controversial discussions on various multi-antenna related issues, as
well as various interactions with numerous colleagues. Obviously, this area of technology
is so large that it was beyond our aim to cover all aspects in details. Rather, our goal has
been to provide researchers, R&D engineers and graduate students with a comprehensive
coverage of radio propagation models and space–time coding techniques.
Mobile wireless communications are in constant evolution due to the continu-
ously increasing requirements and expectations of both users and operators.
Mass multimedia* services have been for a long time expected to generate a large
amount of data traffic in future wireless networks [1]. Mass multimedia services
are, by definition, purposed for many people. In general, it can be distinguished
between the distribution of any popular content over a wide area and the distribu-
tion of location-dependent information in highly populated areas. Representative
examples include the delivery of live video streaming content (like sports compe-
titions, concerts, or news) and file download (multimedia clips, digital newspa-
pers, or software updates).
