ZAHP PRINT ALARM HISTORY |
ZAHO PRINT ALARMS CURRENTLY ON |
ZIGO DISPLAY MML COMMAND LOG |
ZWQO SHOW SOFTWARE PACKAGE INFORMATION |
ZW7I INTERROGATE LICENCE OR FEATURE INFORMATION |
ZEFR RESET SITE/BCF |
ZEQS LOCK UNLOCK BTS |
ZERS LOCK UNLOCK TRX |
ZEQM MODIFY BTS PARAMETERS |
ZEAO OUTPUT GSM ADJACENT |
ZEUO OUTPUT POWER CONTROL PARAMETERS |
ZEHO OUTPUT HANDOVER PARAMETERS |
Nokia BSC with MML commands:
LTE fundamentals
The fundamentals of the LTE Radio interface and get an overview of the evolution of 4G telecommunication. This 19 minutes video is presented by Ericsson expert Sven-Anders Sturesson.
The tutorial gives an overview of the fundamental technology of Long Term Evolution (LTE). You will learn the basics of the LTE radio interface, including multiple input, multiple outputs (MIMO), OFDM, uplink and downlink, SIMO, TDD, FDD, channel coding and GSA.
http://www.ericsson.com/ourportfolio/ericsson-academy/online-tutorials/lte_fundamentals_module/player.html
Source: Ericsson
What is Citrix ?
Citrix facilitates real-time access to shared
applications over networks and the Internet. Remote access to Citrix-enabled
applications can be over DSL, T1, ISDN, or dial-up. Citrix MetaFrame enables
multiple users to run shared applications simultaneously. Communication between
Citrix clients and servers consists of exchange of user inputs (keyboard/mouse)
and screen shots. Citrix MetaFrame runs on Windows NT 4.0 (Terminal Server
Edition) and Windows 2000, with Terminal Services installed.
Citrix products include:
- Citrix
Access Essentials
- Citrix
Access Gateway
- Citrix
Access Suite
- Citrix
Application Gateway
- Citrix
GoToAssist
- Citrix
GoToMeeting
- Citrix
GoToMyPC
- Citrix
NetScaler
- Citrix
Password Manager
- Citrix
Presentation Server
For technical support and questions regarding Citrix
MetaFrame, go to http://support.citrix.com
Multimedia Broadcast Multicast Service, MBMS
Multimedia Broadcast
Multicast Service, MBMS
A new service introduced in 3GPP Release 6 specifications is
Multimedia Broadcast Multicast Service (MBMS). There are two high level modes
of operation in MBMS, as given
1.
Broadcast
mode, which allows sending audio and video. The already existing Cell Broadcast
Service (CBS) is intended for messaging only. The broadcast mode is expected to
be a service without charging and there are no specific activation requirements
for this mode.
2.
Multicast mode allows sending multimedia data
for the end users that are part of a multicast subscription group. End users
need to monitor service announcements regarding service availability, and then
they can join the currently active service. From the network point of view, the
same content can be provided in a point-to-point fashion if there are not
enough users to justify the high power transmission. A typical example in 3GPP
has been the sport results service where, for example, ice hockey results would
be available as well as video clips of the key events in different games of the
day. Charging is expected to be applied for the multicast mode.
From the radio point of view, MBMS is considered an application
independent way to deliver the MBMS User Services, which are intended to
deliver to multiple users simultaneously. The MBMS User Services can be
classified into three groups as follows
1. Streaming services, where a basic example is audio and video
stream;
2. File downloads services;
3. Carousel service, which can be considered as a combination of
streaming and file download. In this kind of service, an end user may have an
application which is provided data repetitively and updates are then broadcast
when there are changes in the content.
For MBMS User Services, an operator controls the distribution of
the data. Unlike CBS, the end user needs first to join the service and only
users that have joined the service can see the content. The charging can then
be based on the subscription or based on the keys which enable an end user to
access the data. The MBMS content can be created by the operator itself or by a
third party and, as such, all the details of what an MBMS service should look like
will not be specified by 3GPP, but left for operators and service providers.
One possible MBMS high level architecture is shown in Figure, where the IP
multicast network refers here to any server providing MBMS content over the
Internet.
Push-to-Talk over Cellular (PoC)
Push-to-talk over cellular (PoC) service is instant in the sense
that the voice connection is established by simply pushing a single button and
the receiving user hears the speech without even having to answer the call.
While ordinary voice is bi-directional, the PoC service is a one directional
service. The basic PoC application may hence be described as a walkie-talkie
application over the packet switched domain of the cellular network. In addition
to the basic voice communication functionality, the PoC application provides
the end user with complementary features like, for example:
·
Ad
hoc and predefined communication groups;
The speech packets are in the PoC solution carried from the sending mobile station to the server by the OPRS/UMTS network. The server then forwards the packets to the receiving mobile stations. In the case of a one-to-many connection, the server multiplies the packets to all the receiving mobile stations. This is illustrated in Figure The PoC service is independent of the underlying radio access network.
·
Access
control so that a user may define who is allowed to make calls to him/her;
·
‘Do-not-disturb’
in case immediate reception of audio is not desirable.
With ordinary voice calls a bi-directional communication channel is
reserved between the end users throughout the duration of the call. In PoC, the
channel is only set up to transfer a short speech burst from one to possibly
multiple users. Once this speech burst has been transferred, the packet
switched communication channel can be released. This difference is highlighted
in Figure.
Differences between WCDMA and Second Generation Air Interfaces
Main differences between the third and second generation air
interfaces are described. GSM and IS-95 (the standard for cdmaOne systems) are
the second generation air interfaces considered here. Other second generation
air interfaces are PDC in Japan and US-TDMA mainly in the Americas; these are
based on TDMA (time division multiple access) and have more similarities with
GSM than with IS-95. The second generation systems were built mainly to provide
speech services in macro cells. To understand the background to the differences
between second and third generation systems, we need to look at the new
requirements of the third generation systems which are listed below:
·
Bit
rates up to 2 Mbps;
·
Variable
bit rate to offer bandwidth on demand;
·
Multiplexing
of services with different quality requirements on a single connection, e.g. speech,
video and packet data;
·
Delay
requirements from delay-sensitive real time traffic to flexible best-effort
packet data;
·
Quality
requirements from 10 % frame error rate to 10_6 bit error
rate;
·
Co-existence
of second and third generation systems and inter-system handovers for coverage
enhancements and load balancing;
·
Support
of asymmetric uplink and downlink traffic, e.g. web browsing causes more loading
to downlink than to uplink;
·
High
spectrum efficiency;
·
Co-existence
of FDD and TDD modes.
GSM also covers services and core network aspects, and this GSM
platform will be used together with the WCDMA air interface: see the next
section regarding core networks.
What is Bluetooth ?
Bluetooth
is a proprietary open wireless technology standard for exchanging data over
short distances (using short-wavelength radio transmissions in the ISM band
from 2400–2480 MHz) from fixed and mobile devices, creating personal area
networks (PANs) with high levels of security. Created by telecoms vendor
Ericsson in 1994,[1] it was originally conceived as a wireless alternative to
RS-232 data cables. It can connect several devices, overcoming problems of
synchronization.
To
understand any kind of communication technology, you should be able to answer
to several basic questions about it. In other words, if you can answer the
following questions, I would say you already have some general understanding on
it.
- Is it wired communication?
or Wireless communication ?
- If it is
wireless communication, what kind of wave length (frequency) range it uses
?
- What is the
typical range of communication? (How far it can go) ?
- What is the
typical data rate you can transmit and receive ?
- What is the
typical connection topology ? (Is it one-to-one connection ? or
one-to-many connection ? etc)
Can
you find the answers to these questions from the wikipedia definition that I
quoted above?
Let's
tackle each of the questions one by one.
- Is it wired communication?
or Wireless communication ? ==> It is 'wireless Communication'.
- If it is
wireless communication, what kind of wave length (frequency) range it uses?
==> It is 2400~2800 Mhz frequency Range called ISM (Industrial Science
Medical) band.
- What is the
typical range of communication ? (How far it can go) ? ==> It is
usually a couple meter range (The wikipedia definition does not explictely
say about the range though)
- What is the
typical data rate you can transmit and receive ? ==> At the beginning,
it started with the max data rate of 1 Mbp and now mostly 2,3 Mbps (EDR).
Recent specification defines the technology for even higher data rate.
- What is the
typical connection topology ? (Is it one-to-one connection ? or
one-to-many connection ? etc) ==> It support both one-to-one and
one-to-many connection.
Typical
Bluetooth Application
Headset
Hands-free Automotive
Dial-up
Networking
Ad-hoc
File Transfer
PC-Peripherals,
Printing
Stereo
Audio
Image
Home
Automation
Music
Player Synch
Video
Transfer
Smart
Remotes
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