This document discusses Digital Audio Broadcasting (DAB) systems. It provides an introduction to DAB and describes some of its key features like providing CD quality audio, robust reception, and ability to transmit ancillary data. It also discusses different DAB standards and specifications like Eureka 147, IBOC, and OFDM modulation. The document outlines the history of DAB and digital radio broadcasting. It provides block diagrams and descriptions of DAB and IBOC system implementations as well as challenges of radio signal propagation in mobile environments.
DVB is a set of standards that define digital broadcasting using existing satellite, cable, and terrestrial infrastructures.
The term digital television is sometimes used as a synonym for DVB
Satellite Link Design:
EIRP, Transmission Losses, Free-space transmission, System noise temperature and G/T ratio, Noise figure, Design of downlinks, Design of uplink, Design of specified C/N: combining C/N and C/I values in satellite links, Overall C/No, Link design procedure.
DVB is a set of standards that define digital broadcasting using existing satellite, cable, and terrestrial infrastructures.
The term digital television is sometimes used as a synonym for DVB
Satellite Link Design:
EIRP, Transmission Losses, Free-space transmission, System noise temperature and G/T ratio, Noise figure, Design of downlinks, Design of uplink, Design of specified C/N: combining C/N and C/I values in satellite links, Overall C/No, Link design procedure.
Attitude & orbital control system, TTC & M system, Power system, Communication subsystem, Satellite antenna, Space qualification, Equipment Reliability, redundancy
Channelization is a multiple-access method in which the available bandwidth of a link is shared in time, frequency, or through code, between different stations. The three channelization protocols are FDMA, TDMA, and CDMA
EFFECTS OF FILTERS ON THE PERFORMANCE OF DVB-T RECEIVERijwmn
Digital Video Broadcasting-Terrestrial (DVB-T) is an international standard for digital television
services. Orthogonal Frequency Division Multiplexing (OFDM) is the core of this technology. OFDM
based system like DVB-T can handle multipath fading and hence it can minimize Inter Symbol
Interference (ISI). DVB-T has some limitations too namely large dynamic range of the signals and
sensitivity to frequency error. In order to overcome these limitations DVB-T receivers should be optimally
designed. In this paper we address the issues related to optimal DVB-T receiver design. There of several
signal processing units in a DVB-T receiver. A low-pass filter is one of them. In this paper, we consider
some classic filters namely Butterworth, Chebyshev, and elliptic in the DVB-T receiver. The effects of
different filters on the performances of DVB-T receiver have been investigated and compared in this
paper under AWGN channel condition
Attitude & orbital control system, TTC & M system, Power system, Communication subsystem, Satellite antenna, Space qualification, Equipment Reliability, redundancy
Channelization is a multiple-access method in which the available bandwidth of a link is shared in time, frequency, or through code, between different stations. The three channelization protocols are FDMA, TDMA, and CDMA
EFFECTS OF FILTERS ON THE PERFORMANCE OF DVB-T RECEIVERijwmn
Digital Video Broadcasting-Terrestrial (DVB-T) is an international standard for digital television
services. Orthogonal Frequency Division Multiplexing (OFDM) is the core of this technology. OFDM
based system like DVB-T can handle multipath fading and hence it can minimize Inter Symbol
Interference (ISI). DVB-T has some limitations too namely large dynamic range of the signals and
sensitivity to frequency error. In order to overcome these limitations DVB-T receivers should be optimally
designed. In this paper we address the issues related to optimal DVB-T receiver design. There of several
signal processing units in a DVB-T receiver. A low-pass filter is one of them. In this paper, we consider
some classic filters namely Butterworth, Chebyshev, and elliptic in the DVB-T receiver. The effects of
different filters on the performances of DVB-T receiver have been investigated and compared in this
paper under AWGN channel condition
satellite communication jntuh
Satellite Link Design: Basic Transmission Theory, System Noise Temperature, and G/T Ratio,
Design of Down Links, Up Link Design, Design Of Satellite Links For Specified C/N, System Design
Examples.
Multiple Access: Frequency Division Multiple Access (FDMA), Inter modulation, Calculation of C/N,
Time Division Multiple Access (TDMA), Frame Structure, Examples, Satellite Switched TDMA
Onboard Processing, DAMA, Code Division Multiple Access (CDMA), Spread Spectrum Transmission
and Reception.
Min input and min output of the system can be conduct by the process of interest in the process of view of synchronisation and software Engineer at the system can be a good idea for this colour combination of view of the best part of the system can be conduct by the process of view till now I'm interested for the system based engineering and technology related issues in college and software engineer h today’s increasing demand for security, especially in public places such as
airports, train stations, supermarkets, schools, and crowded street, surveillance cameras are
used for monitoring daily activities and detecting abnormal events. This task focuses on the
localization of anomalies using both temporal and partial information in videos. Anomalies
can be defined as events deviating from normal behavior [1], e.g., fighting, sneaking,
or unattended bags at an airport. The purpose of using surveillance cameras is the early
detection of anomalous human behaviors. This is a critical task in many cases where human
intervention is necessary, e.g., for crime prevention or countering terrorism. However,
this process requires labor-intensive and continuous human attention, which is a tedious
process, since abnormal events only happen 0.01% of the time and 99.9% of the surveillance
time is wasted [2]. Moreover, a surveillance system produces a lot of redundant video data,
which require unnecessary storage space. For reducing human errors and storage costs, it
is necessary to build an efficient surveillance system for detecting any strange behaviors
that may lead to dangerous situations. This requires deep and comprehensive study of
human activity recognition, to understand the features representative of each action.
Anomaly detection in video has a wide range of applications, such as for traffic
accident detection, criminal activity detection, and illegal activity detection. In addition,
detecting anomalous items or abandoned objects, such as guns or knifes, is necessary in
sensitive area
Acetabularia Information For Class 9 .docxvaibhavrinwa19
Acetabularia acetabulum is a single-celled green alga that in its vegetative state is morphologically differentiated into a basal rhizoid and an axially elongated stalk, which bears whorls of branching hairs. The single diploid nucleus resides in the rhizoid.
How to Make a Field invisible in Odoo 17Celine George
It is possible to hide or invisible some fields in odoo. Commonly using “invisible” attribute in the field definition to invisible the fields. This slide will show how to make a field invisible in odoo 17.
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
A Strategic Approach: GenAI in EducationPeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
Instructions for Submissions thorugh G- Classroom.pptxJheel Barad
This presentation provides a briefing on how to upload submissions and documents in Google Classroom. It was prepared as part of an orientation for new Sainik School in-service teacher trainees. As a training officer, my goal is to ensure that you are comfortable and proficient with this essential tool for managing assignments and fostering student engagement.
Macroeconomics- Movie Location
This will be used as part of your Personal Professional Portfolio once graded.
Objective:
Prepare a presentation or a paper using research, basic comparative analysis, data organization and application of economic information. You will make an informed assessment of an economic climate outside of the United States to accomplish an entertainment industry objective.
Welcome to TechSoup New Member Orientation and Q&A (May 2024).pdfTechSoup
In this webinar you will learn how your organization can access TechSoup's wide variety of product discount and donation programs. From hardware to software, we'll give you a tour of the tools available to help your nonprofit with productivity, collaboration, financial management, donor tracking, security, and more.
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
3. Introduction
Replace the existing AM and FM audio
broadcast services
Very well suited for mobile reception
High robustness against Multipath
reception
High quality digital audio services (near
CD quality)
3/2/2007
Digital Audio Broadcasting systems
3
4. Introduction
Ancillary data transmission (e.g. travel
and traffic information, still and moving
pictures, etc.)
Larger coverage area than current FM
and AM systems
Efficient frequency spectrum use
Low transmitting power
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Digital Audio Broadcasting systems
4
5. DAB species
DAB (Eureka 147 project)
ETSI standard
In Band On Channel (IBOC) DAB
(High definition radio project)
NRSC standard
ISDB
Japanese standard
Digital TV & audio
3/2/2007
Digital Audio Broadcasting systems
5
6. History of DAB
In 1980s the first digital sound broadcasting
systems providing CD like audio quality for
satellite delivery.
Frequency band 10 to 12GHz
Little sound data compression
Not aimed at mobile reception
In 1987 the Eureka-147 project was born
First DAB standard was achieved in 1993
In 1995 the ETSI adopted DAB as the only
European standard for digital radio
3/2/2007
Digital Audio Broadcasting systems
6
7. DAB specification
1.5 MHz bandwidth
Frequency band between 30MHz to
3GHz
1.5 Mbit/s signal rate
8-384 kbit/s audio rate
Up to 63 mono audio channel or 12
stereo audio channel
3/2/2007
Digital Audio Broadcasting systems
7
9. Important block
24 or 48 Khz
PCM audio signal
To RF Unit
Mpeg II
Encoder
3/2/2007
Energy
dispersal
scrambler
Covoloutio
nal
Encoder
Time
Interleaving
QPSK
symbol
Mapper
Digital Audio Broadcasting systems
OFDM
symbol
Gernerator
9
10. DAB World Coverage Map
[6]
3/2/2007
Digital Audio Broadcasting systems
10
11. IBOC DAB
Permit a smooth evolution from current
analog radio broadcasting to fully digital radio
broadcasting.
Allow broadcaster to keep current analog
transmission
No new spectrum required for AM or FM
transmission
Near CD Quality for FM
FM stereo quality sound for AM station
No new tower or transmitter site
New data capabilities for AM and FM stations
3/2/2007
Digital Audio Broadcasting systems
11
12. IBOC DAB History
2001
iBiquity was born
2002
IBOC technology approved by the FCC
2003
First AM and FM stations begin
broadcasting with HD Radio
April, 2005
IBOC DAB Standard (NRSC-5) approved
3/2/2007
Digital Audio Broadcasting systems
12
13. IBOC DAB
RF/transmission subsystem
Coding and interleaving
Mapping
Orthogonal frequency division multiplexing
(OFDM) modulation
Up-conversion to the AM or FM band
Transport and service multiplex
Takes the audio and data information
Generate stream of packets
Audio and data input subsystems
Audio source coding
3/2/2007
Digital Audio Broadcasting systems
13
21. Attenuation source
Any objects which obstruct the line of
sight signal
Diffract off the boundaries of obstructions
Low frequencies diffracting more than high
frequency signals
High frequency signals, require line of
sight for adequate signal strength
3/2/2007
Digital Audio Broadcasting systems
21
23. Fast fading
Relative phase of multiple reflected signals can cause
constructive or destructive interference at the receiver
[3]
3/2/2007
Digital Audio Broadcasting systems
23
24. Rayleigh Fading
Rayleigh distribution describes the
probability of the signal level being
received due to fading.
3/2/2007
Digital Audio Broadcasting systems
24
25. Frequency Selective Fading
Channel spectral response is not flat
Deep nulls in the received signal power
For narrow bandwidth entire signal can
be lost
This can overcome in two ways:
Transmitting a spread spectrum as CDMA
Split the transmission into many small
bandwidth carriers (OFDM)
3/2/2007
Digital Audio Broadcasting systems
25
26. Delay Spread
Time spread between the arrival of
the first and last multipath signal
Lead to inter-symbol interference
ISI can be minimized by CDMA or
OFDM
[3]
3/2/2007
Digital Audio Broadcasting systems
26
27. Doppler Shift
When a wave source and a receiver are
moving relative to one another the
frequency of the received signal changed
Significant problems
If transmission technique is sensitive to
carrier frequency offsets (COFDM)
Relative speed is very high
3/2/2007
Digital Audio Broadcasting systems
27
28. OFDM
Similar to FDM but OFDM uses the spectrum
much more efficiently
Multicarrier technique
Divides the spectrum
into many carriers
Sub carrier are orthogonal to each other
bandwidth of each channel is typically 10kHz30kHz (for voice communications)
Multipath tolerance (by guard interval)
3/2/2007
Digital Audio Broadcasting systems
28
30. OFDM
Noise performance was depend on the
modulation technique used for modulating
each carrier
Minimum SNR required for BPSK was ~7dB,
~12dB for QPSK and ~25dB for 16PSK
Total immunity to multipath delay spread
when reflection time is less then the guard
period
Delay Spreads of up to 100µsec could be
tolerated, corresponding to multipath
reflections of 30km
3/2/2007
Digital Audio Broadcasting systems
30
31. OFDM
It is very sensitive to frequency, and
phase errors between the transmitter
and receiver
phase noise of the transmitter
Frequency offset errors between the
transmitter and receiver
This problem can be overcome by
synchronizing the clocks or by reducing
the number of carriers used.
3/2/2007
Digital Audio Broadcasting systems
31
32. OFDM
Clipping of the OFDM signal have little
effect on the performance
Allowing the peak power of the signal
to be clipped up to 6 - 9dB
Tolerance to clipping reduces the
dynamic range overhead
3/2/2007
Digital Audio Broadcasting systems
32
33. Adding Guard interval to OFDM
Robustness against multipath delay
spread
The level of robustness, can be
increased more by the addition of a
guard period
Cyclic extension effectively extends the
length of the symbol without loss of
orthogonality
3/2/2007
Digital Audio Broadcasting systems
33
34. OFDM system implementation
Using general purpose DSPs
most of the processing is required in
performing the fast fourier transform
(FFT)
The complexity of performing an FFT is
dependent on the size of the FFT.
3/2/2007
Digital Audio Broadcasting systems
34
37. CDMA
What is CDMA (Code Division Multiple
Access)
Spread spectrum technique
Narrow band message is multiplied by a
pseudo random noise code (PN code)
All channels use the same frequency
band and transmit simultaneously
Signal is recovered by correlating the
received signal with the PN code used
3/2/2007
Digital Audio Broadcasting systems
37
38. CDMA DAB
[3]
Signal hiding and non-interference with
existing systems.
Accurate Ranging
Multiple User Access
Multipath tolerance
3/2/2007
Digital Audio Broadcasting systems
38
40. CDMA
Data to be
transmitted is
spread by
modulating the
data using a PN
code.
Received signal is
recovered by
multiplying the
signal by the
original spreading
code
[3]
3/2/2007
Digital Audio Broadcasting systems
40
41. Comparison
OFDM was found to perform very well
compared with CDMA
OFDM allow up to 2-10 times more
channel than CDMA
3/2/2007
Digital Audio Broadcasting systems
41
42. Reference
1.
2.
3.
4.
5.
NRSC-5 standard: “In-Band on Channel Digital Radio
Broadcasting Standard NRSC-5,” April, 2005.
H. U. Bilbao, “DAB Transmission System Simulation,”M.Sc
Thesis, August 2004.
E. Lawrey, “The suitability of OFDM as a modulation
technique for wireless telecommunications, with a CDMA
comparison” M.SC Thesis
S.Y. Yeo, M.S. Beak, M.J. Kim, Y.H. You, "High capacity and
reliability techniques for digital audio broadcasting system,"
IEEE Transactions on Consumer Electronics, vol. 50, no. 2,
MAY 2004.
H. C. Papadopoulos, C. W. Sundberg, “Postcanceling
techniques for simultaneous broadcasting of analog FM and
digital data," IEEE Transactions on Communications, vol. 51,
no. 1, January 2003[3]
3/2/2007
Digital Audio Broadcasting systems
42
43. References
6.
ETSI EN 300 401 “Radio Broadcasting Systems
Digital Audio Broadcasting (DAB) to mobile,
portable and fixed receivers”
3/2/2007
Digital Audio Broadcasting systems
43