Transmission system used for optical fibers Jay Baria
In this presentation I have explained various types of transmission system used for optical transmission and also described about the budget method that has to be followed while selecting an source for optical fibers and also about the factors that should be consider while selecting an source.
A general overview of signal encoding
You will learn why to use digital encoding, how signal is transmitted and received and how analog signals are converted to digital
Some digital encoding methods
A presentation prepared by my friend's friend. I have done no editing at all, I'm just uploading the presentation as it is.
OTDR(OPTICAL TIME DOMAIN REFLECTOMETER)Shail Mishra
OTDR, OPTICAL TIME DOMAIN REFLECTOMETER, How to calculate link budget, Basic of Wavelength, FTTH Network, Working Principle of OTDR, OTDR BASIC PARAMETER.
Transmission system used for optical fibers Jay Baria
In this presentation I have explained various types of transmission system used for optical transmission and also described about the budget method that has to be followed while selecting an source for optical fibers and also about the factors that should be consider while selecting an source.
A general overview of signal encoding
You will learn why to use digital encoding, how signal is transmitted and received and how analog signals are converted to digital
Some digital encoding methods
A presentation prepared by my friend's friend. I have done no editing at all, I'm just uploading the presentation as it is.
OTDR(OPTICAL TIME DOMAIN REFLECTOMETER)Shail Mishra
OTDR, OPTICAL TIME DOMAIN REFLECTOMETER, How to calculate link budget, Basic of Wavelength, FTTH Network, Working Principle of OTDR, OTDR BASIC PARAMETER.
In digital modulation, minimum-shift keying(MSK) is a type of continuous-phase frequency-shift keying that was developed in the late 1950s and 1960s.
Similar to OQPSK(Offset quadrature phase-shift keying),
LEDs are of interest for fibre optics because of five inherent characteristics..
How it works?
Spectrum of an LED
Modulation of LED
LED Vs. Laser diode
disadvantages of LED
This presentation & video explains electromagnetic spectrum, frequency, band, bandwidth and how these concepts are used in mobile technology. We also look at antennas for smartphones including 2G, 3G, 4G and 5G
The Presentation includes Basics of Non - Uniform Quantization, Companding and different Pulse Code Modulation Techniques. Comparison of Various PCM techniques is done considering various Parameters in Communication Systems.
>Introduction to Digital Signal Processing
>Analog Signal Processing Versus Digital Signal Processing
>Classification Of Signals
>Comparison Between Continuous-Time & Discrete-Time Sinusoids
>Characteristics Of Discrete-time Sinusoids
>A/D and D/A Conversion
FellowBuddy.com is an innovative platform that brings students together to share notes, exam papers, study guides, project reports and presentation for upcoming exams.
We connect Students who have an understanding of course material with Students who need help.
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Our Vision & Mission – Simplifying Students Life
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In digital modulation, minimum-shift keying(MSK) is a type of continuous-phase frequency-shift keying that was developed in the late 1950s and 1960s.
Similar to OQPSK(Offset quadrature phase-shift keying),
LEDs are of interest for fibre optics because of five inherent characteristics..
How it works?
Spectrum of an LED
Modulation of LED
LED Vs. Laser diode
disadvantages of LED
This presentation & video explains electromagnetic spectrum, frequency, band, bandwidth and how these concepts are used in mobile technology. We also look at antennas for smartphones including 2G, 3G, 4G and 5G
The Presentation includes Basics of Non - Uniform Quantization, Companding and different Pulse Code Modulation Techniques. Comparison of Various PCM techniques is done considering various Parameters in Communication Systems.
>Introduction to Digital Signal Processing
>Analog Signal Processing Versus Digital Signal Processing
>Classification Of Signals
>Comparison Between Continuous-Time & Discrete-Time Sinusoids
>Characteristics Of Discrete-time Sinusoids
>A/D and D/A Conversion
FellowBuddy.com is an innovative platform that brings students together to share notes, exam papers, study guides, project reports and presentation for upcoming exams.
We connect Students who have an understanding of course material with Students who need help.
Benefits:-
# Students can catch up on notes they missed because of an absence.
# Underachievers can find peer developed notes that break down lecture and study material in a way that they can understand
# Students can earn better grades, save time and study effectively
Our Vision & Mission – Simplifying Students Life
Our Belief – “The great breakthrough in your life comes when you realize it, that you can learn anything you need to learn; to accomplish any goal that you have set for yourself. This means there are no limits on what you can be, have or do.”
Like Us - https://www.facebook.com/FellowBuddycom
It is a digital representation of an analog signal that takes samples of the amplitude of the analog signal at regular intervals. The sampled analog data is changed to, and then represented by, binary data.
A Brief Knowledge about Differential Pulse Code Modulation.
It contains the basics of Pulse Code modulation and why we all switching to Differential Pulse Code Modulation.
All the things about the Differential Pulse Code Modulation is given in a good understandable way
Introduction to Phased Array Using the OmniScan MX2 - Part TwoOlympus IMS
Free webinar available: http://bit.ly/LTH8jA
OmniScan MX2 product details: http://bit.ly/1e6mjY8
Part two of the series will cover sector scan basics and introduction to the data views and displays commonly used in automated UT and phased array. This includes use of the OmniScan MX2 group setup wizards, and setup and configuration of the UT parameters.
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Digital Communication Essentials: DPCM, DM, and ADM .pptxpritamlangde
Digital Communication: Digital communication refers to the transmission of information using digital signals, where data is represented by discrete symbols or values. It encompasses various techniques for encoding, transmitting, and decoding digital data, including text, images, audio, and video. Digital communication systems offer advantages such as improved signal quality, noise immunity, and the ability to multiplex multiple data streams.
Differential Pulse Code Modulation (DPCM): DPCM is a digital modulation technique used for encoding analog signals into digital form. In DPCM, the difference between the current sample and the predicted value of the sample is quantized and encoded, rather than encoding the absolute sample value directly. This technique can reduce the amount of data required for transmission compared to standard pulse code modulation (PCM), especially for signals with correlation between successive samples.
Delta Modulation (DM): Delta modulation is a simple form of analog-to-digital conversion where the difference (delta) between the current sample and the previous sample is quantized and encoded. In DM, only the sign of the difference (positive or negative) is transmitted, which simplifies the encoding process. However, DM may suffer from quantization noise and limited signal fidelity, especially for rapidly changing or high-frequency signals.
Adaptive Delta Modulation (ADM): Adaptive delta modulation is an extension of delta modulation that dynamically adjusts the step size or quantization level based on the characteristics of the input signal. Unlike fixed-step delta modulation, ADM can adapt to changes in signal amplitude or frequency, resulting in improved signal fidelity and reduced quantization error. ADM is particularly useful for encoding signals with varying dynamics or signal-to-noise ratios
Simple description about the analog and digital signals
and a description about analog to digital conversion &
digital to analog conversion..............
2. First, a few definitions…
An analog to digital converter (ADC) changes an analog signal into a digital
one. Some examples: voice, temperature, pressure
A quantizer takes a set of input values and maps it to a smaller set of
values, usually a predetermined range of voltages.
A limiter is a circuit that allows signals below a specified input power or
level to pass unaffected while attenuating the peaks of stronger signals
that exceed this threshold to prevent distortion.
Sampling is the reduction of a continuous time signal to a discrete signal, a
sequence of quantities.
Pulse code modulation is sampling an analog signal to derive a data
stream, a series of 1s and 0s.
3. Delta Modulation
An analog-to-digital and digital-to-
analog signal conversion technique
Simplest form of differential pulse-
code modulation (DPCM)
Periodically samples the input
message, to make a comparison of the
current sample with that preceding it,
and outputs a single bit which
indicates the sign of the difference
between the two samples.
4. Delta Modulation
Delta Modulated Signal
• Note the saw-tooth waveform
• Transmitted data is reduced to a 1-bit data stream.
• Each segment of the approximated signal is
compared to the original analog wave to determine
the increase or decrease in relative amplitude.
5. Delta Modulation
Demodulated Delta Signal:
• Input speech message Yellow
• Demodulated message Green
Visible noise difference
between original message and
demodulated message
6. Delta Modulation - Advantages
SNR – Delta modulation gives a higher signal-to-noise ratio than other
conventional modulation techniques
Bandwidth - lower channel bandwidth consumption. Sending one binary bit
as a carrier pulse with one sample of digitized data lowers the bandwidth of
the transmission channel
Simple circuitry – adder, integrator, quantizer, LPF for demodulation
7. Delta Modulation - Disadvantages
Slope overload - If the input
signal is rising or falling with a
slope larger than Δ/T, where T is
the sampling time, we say that
the sampler is suffering from
slope overload.
Granular noise –the output
signal must always either
increase by a step, or decrease
by a step, and cannot stay at a
single value. This means that if
the input signal is level, the
output signal could be
oscillatory.
Increased step size to alleviate slope overload
9. Delta-Sigma Modulation
Delta-Sigma Modulated Signal
• More closely related to the original wave
Places an integrator in between the source
and the summer which obviates the need
for an integrator at demodulation, so the
demodulator can be a simple LPF.
Adaptation of step size
10. Delta-Sigma Modulation Advantages
Attempts to alleviate avoid slope overload, reducing quantization error.
Resulting analog signal then added to the input signal
Reduces error introduced by the delta-modulation.
Used in modern electronics
Converters, switched-mode power supplies, motor controllers
Also used in some high-performance data-acquisition devices
13. Adaptive Delta Modulation
Adaptive Delta Modulated Signal
A large step size was required when sampling those
parts of the input waveform of steep slope. But a
large step size worsened the granularity of the
sampled signal when the waveform being sampled
was changing slowly.
A small step size is needed for when the slope is
changing quickly.
14. Adaptive Delta Modulation
Allows for a controllable step size to be implemented
Continuous Variable Slope Delta Modulation (CVSDM)
Encodes the difference between predicted samples and speech samples
Provides a more efficient comparison and reduction in the number of bits per
sample.
Commonly used in short-range wireless digital voice transmission for its
low implementation cost and robustness in dealing with bit errors
