-
The first Third Generation Partnership Project (3GPP) Wideband Code Division
Multiple Access (WCDMA) networks were launched during 2002. By the end of 2005
there were 100 open WCDMA networks and a total of over 150 operators having
frequency licenses for WCDMA operation. Currently, the WCDMA networks are
deployedinUniversalMobileTelecommunicationsSystem(UMTS)bandaround2GHz
in Europe and Asia including Japan and Korea. WCDMA in America is deployed in the
existing 850 and 1900 spectrum allocations while the new 3G band at 1700/2100 is
expected to be available in the near future. 3GPP has defined the WCDMA operation
also for several additional bands, which are expected to be taken into use during the
coming years.
標(biāo)簽:
HSDPAHSUPA
Access
Speed
Radio
UMTS
High
for
上傳時間:
2020-05-27
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-
This book addresses two aspects of network operation quality; namely, resource
management and fault management.
Network operation quality is among the functions to be fulfilled in order to offer
quality of service, QoS, to the end user. It is characterized by four parameters:
– packet loss;
– delay;
– jitter, or the variation of delay over time;
– availability.
Resource management employs mechanisms that enable the first three parameters
to be guaranteed or optimized. Fault management aims to ensure continuity of service.
標(biāo)簽:
Ethernet
Networks
MPLS
and
IP
上傳時間:
2020-05-27
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-
This book presents millimeter wave communication system design and analysis at the
level to produce an understanding of the interaction between a wireless system and its
front end so that the overall performance can be predicted. Gigabit wireless commu-
nications require a considerable amount of bandwidth, which can be supported by
millimeter waves. Millimeter wave technology has come of age, and at the time of
writing the standards of IEEE 802.15.3c, WiGig, Wireless HD TM , and the European
Computer Manufacturers Association have recently been finalized.
標(biāo)簽:
Communication
Millimeter
Systems
Wave
上傳時間:
2020-05-28
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This book is about multipoint cooperative communication, a key technology to
overcome the long-standing problem of limited transmission rate caused by inter-
point interference. However, the multipoint cooperative communication is not an
isolated technology. Instead, it covers a vast range of research areas such as the
multiple-input multiple-outputsystem, the relay network, channel state information
issues, inter-point radio resource management operations, coordinated or joint
transmissions, etc. We suppose that any attempt trying to thoroughly analyze the
multipoint cooperative communication technology might end up working on a
cyclopedia for modern communication systems and easily get lost in discussing all
kinds of cooperative communication schemes as well as the associated models and
their variations.
標(biāo)簽:
Communication
Multi-point
Cooperative
Systems
上傳時間:
2020-05-31
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-
The unguided transmission of information using electromagnetic waves
at radio frequency (RF) is often referred to as wireless communications,
the first demonstration of which took place at the end of the 19th cen-
tury and is attributed to Hertz. The technology was, shortly thereafter,
commercialised by, amongst others, Marconi in one of the first wire-
less communication systems, i.e., wireless telegraphy. In the first half of
the 20th century the technology was developed further to enable more
than the mere transmission of Morse code. This first resulted in uni-
directional radio broadcasting and several years later also in television
broadcasting.
標(biāo)簽:
Imperfections
RF
上傳時間:
2020-06-01
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-
The following sections profile many of the vendors in the NFV market. The individual profiles were created
through a collaborative effort between SDNCentral’s Research Team and the Vendor’s product experts.
SDNCentral worked under the assumption the information provided by the vendors was factual, auditing the
submissions only to remove unverifiable claims and hyperbole. Extended profiles can be viewed online.
While every attempt has been made to validate the capabilities listed in the profiles, SDNCentral advises end
users to verify the veracity of each claim for themselves in their actual deployment environments. SDNCentral
cannot be held liable for unexpected operations, damages or incorrect operation due to any inaccuracies listed
here. SDNCentral welcomes feedback and additional information from end users based on their real-world
experiences with the products and technologies listed. The SDNCentral research team can be reached at
標(biāo)簽:
SDxCentral-Mega-NFV-Report
上傳時間:
2020-06-01
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-
A wireless ad-hoc network is a wireless network deployed without any infrastructure. In
such a network, there is no access point or wireless router to forward messages among the
computing devices. Instead, these devices depend on the ad-hoc mode of their wireless net‐
work interface cards to communicate with each other. If the nodes are within the transmis‐
sion range of the wireless signal, they can send messages to each other directly. Otherwise,
the nodes in between will forward the messages for them. Thus, each node is both an end
system and a router simultaneously.
標(biāo)簽:
WIRELESS
NETWORKS
AD-HOC
上傳時間:
2020-06-01
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-
Fun. We (your authors) wanted a word to describe our ultimate goal for this book, as well as a word
we hope you (our reader) will use to describe it, and that’s the one we chose. There are others goals,
of course, but in the end, when you’ve finished the book, we’re hoping you’ll have enjoyed the
activities described in these pages.
Many books use the Introduction to explain exactly what the book is about, what the reader will
learn, what the reader needs (a skill or maybe an item or piece of software), and what the reader
will be left with when that last page is completed. And this Introduction will do those things, but …
hopefully it’ll make you excited to get started.
標(biāo)簽:
Adventures
Arduino
Station
Escape
Gemini
from
上傳時間:
2020-06-09
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-
I can remember buying my first electronic calculator. I was teaching a graduate level statistics course and I
had to have a calculator with a square root function. Back in the late 1960s, that was a pretty high-end
requirement for a calculator. I managed to purchase one at the “educational discount price” of $149.95!
Now, I look down at my desk at an ATmega2560 that is half the size for less than a quarter of the cost and
think of all the possibilities built into that piece of hardware. I am amazed by what has happened to
everything from toasters to car engines. Who-da-thunk-it 40 years ago?
標(biāo)簽:
Beginning
Arduino
for
上傳時間:
2020-06-09
上傳用戶:shancjb
-
A kinematically redundant manipulator is a serial robotic arm that has more
independently driven joints than are necessary to define the desired pose (position
and orientation) of its end-effector. With this definition, any planar manipulator (a
manipulator whose end-effector motion is restrained in a plane) with more than
three joints is a redundant manipulator. Also, a manipulator whose end-effector can
accept aspatialposeisaredundant manipulator ifithas morethan sixindependently
driven joints. For example, the manipulator shown in Fig. 1.1 has two 7-DOF arms
mounted on a torso with three degrees of freedom (DOFs). This provides 10 DOFs
for each arm. Since the end-effector of each arm can have a spatial motion with six
DOFs, the arms are redundant.
標(biāo)簽:
Autonomous
Modeling
Planning
Robots
Path
上傳時間:
2020-06-10
上傳用戶:shancjb