1) Digital communication systems can transmit signals over long distances using regenerators that recover the original data sequence at each segment. This allows for much lower error rates than analog systems.
2) The maximum transmission rate through a channel is 2 times the channel bandwidth. More data can be sent by increasing the number of amplitude levels used to encode each pulse. However, noise places an ultimate limit on transmission rate as it increases bit error rates.
3) Shannon's channel capacity formula describes the maximum reliable transmission rate for a channel based on its bandwidth and signal-to-noise ratio. Rates below the capacity can achieve arbitrarily low error rates with sufficient coding.
Applications of information theory in communication engineeringAbdul Razaq
this presentation describe source coding and channel coding
with error detection and correction technique and defines information theory and coding theory..abdul razaque
AUDIO VOICE RECORDER AND TRANSMISSION THROUGH A WIRELESS MEDIUM BETWEEN PC AN...wadzani umaru
There is a fast growing need to support audio voice communication in wireless channel between a voice source and personal computer PC. In this paper we develop an algorithm using matlab software to indicate how a PC can receive audio voice signal from an audio source, record it and plot the resulting waveform on a graphical representation. The
actual data rate for audio voice transmission over IP is 64000bps, which was used as medium for audio voice communication between a PC and audio voice source
Applications of information theory in communication engineeringAbdul Razaq
this presentation describe source coding and channel coding
with error detection and correction technique and defines information theory and coding theory..abdul razaque
AUDIO VOICE RECORDER AND TRANSMISSION THROUGH A WIRELESS MEDIUM BETWEEN PC AN...wadzani umaru
There is a fast growing need to support audio voice communication in wireless channel between a voice source and personal computer PC. In this paper we develop an algorithm using matlab software to indicate how a PC can receive audio voice signal from an audio source, record it and plot the resulting waveform on a graphical representation. The
actual data rate for audio voice transmission over IP is 64000bps, which was used as medium for audio voice communication between a PC and audio voice source
Wireless digital communication and coding techniques newClyde Lettsome
Lecture about some modern digital communication techniques in this lecture. These techniques will include but are not limited to:
- Code Error Detection and correction
- Parity
- Cyclical Redundancy Coding (CRC)
- Hamming Code
- Digital Modulation Techniques
- Frequency Shift Keying (FSK)
- Binary Phase Shift Keying (BPSK)
- Quadrature Phase Shift Keying (QPSK)
- Channel Access
- Time Division Multiple Access (TDMA)
- Code Division Multiple Access (CDMA)
In this presentation, production of digital audio is discussed. Also brief introduction about digital audio broadcast, recording techniques and stereo phony is given.
Mixing for games levels and more... jocelyn daoustMary Chan
Being part of the entertainment world, video games, gaming consoles and computers are everywhere. More and more people play on home theatre systems and believe that good sound plays a major role in their gaming experience.
The topic of mixing will be approached from technical, artistic and aesthetic standpoints.
Levels and measurement tools will be presented and explained.
Wireless digital communication and coding techniques newClyde Lettsome
Lecture about some modern digital communication techniques in this lecture. These techniques will include but are not limited to:
- Code Error Detection and correction
- Parity
- Cyclical Redundancy Coding (CRC)
- Hamming Code
- Digital Modulation Techniques
- Frequency Shift Keying (FSK)
- Binary Phase Shift Keying (BPSK)
- Quadrature Phase Shift Keying (QPSK)
- Channel Access
- Time Division Multiple Access (TDMA)
- Code Division Multiple Access (CDMA)
In this presentation, production of digital audio is discussed. Also brief introduction about digital audio broadcast, recording techniques and stereo phony is given.
Mixing for games levels and more... jocelyn daoustMary Chan
Being part of the entertainment world, video games, gaming consoles and computers are everywhere. More and more people play on home theatre systems and believe that good sound plays a major role in their gaming experience.
The topic of mixing will be approached from technical, artistic and aesthetic standpoints.
Levels and measurement tools will be presented and explained.
QUANTIZATION
Audio signals are continuous in time and amplitude
Audio signal must be digitized in both time and amplitude to be represented in binary form.
Discrete in time by sampling – Nyquist
Discrete in amplitude by quantization
Once samples have been captured, they must be made discrete in amplitude.
The Art Pastor's Guide to Sabbath | Steve ThomasonSteve Thomason
What is the purpose of the Sabbath Law in the Torah. It is interesting to compare how the context of the law shifts from Exodus to Deuteronomy. Who gets to rest, and why?
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.
How to Split Bills in the Odoo 17 POS ModuleCeline George
Bills have a main role in point of sale procedure. It will help to track sales, handling payments and giving receipts to customers. Bill splitting also has an important role in POS. For example, If some friends come together for dinner and if they want to divide the bill then it is possible by POS bill splitting. This slide will show how to split bills in odoo 17 POS.
How to Create Map Views in the Odoo 17 ERPCeline George
The map views are useful for providing a geographical representation of data. They allow users to visualize and analyze the data in a more intuitive manner.
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
2. Analog Long-Distance Communications Each repeater attempts to restore analog signal to its original form Restoration is imperfect Distortion is not completely eliminated Noise & interference is only partially removed Signal quality decreases with # of repeaters Communications is distance-limited Still used in analog cable TV systems Analogy: Copy a song using a cassette recorder 2 Digital Communication Basics Anish Goel
3. Analog vs. Digital Transmission 3 Digital Communication Basics Anish Goel
4. Digital Long-Distance Communications Regenerator recovers original data sequence and retransmits on next segment Can design so error probability is very small Then each regeneration is like the first time! Analogy: copy an MP3 file Communications is possible over very long distances Digital systems vs. analog systems Less power, longer distances, lower system cost Monitoring, multiplexing, coding, encryption, protocols… 4 Digital Communication Basics Anish Goel
5. Digital Binary Signal For a given communications medium: How do we increase transmission speed? How do we achieve reliable communications? Are there limits to speed and reliability? 5 Digital Communication Basics Anish Goel
6. Pulse Transmission Rate Objective: Maximize pulse rate through a channel, that is, make T as small as possible If input is a narrow pulse, then typical output is a spread-out pulse with ringing Question: How frequently can these pulses be transmitted without interfering with each other? Answer: 2 x Wc pulses/second where Wc is the bandwidth of the channel 6 Digital Communication Basics Anish Goel
7. Bandwidth of a Channel If input is sinusoid of frequency f, then output is a sinusoid of same frequency f Output is attenuated by an amount A(f) that depends on f A(f)≈1, then input signal passes readily A(f)≈0, then input signal is blocked Bandwidth Wc is range of frequencies passed by channel 7 Digital Communication Basics Anish Goel
8. Multilevel Pulse Transmission Assume channel of bandwidth Wc, and transmit 2 Wcpulses/sec (without interference) If pulses amplitudes are either -A or +A, then each pulse conveys 1 bit, so Bit Rate = 1 bit/pulse x 2Wc pulses/sec = 2Wc bps If amplitudes are from {-A, -A/3, +A/3, +A}, then bit rate is 2 x 2Wc bps By going to M = 2m amplitude levels, we achieve Bit Rate = m bits/pulse x 2Wc pulses/sec = 2mWc bps In the absence of noise, the bit rate can be increased without limit by increasing m 8 Digital Communication Basics Anish Goel
9. Noise & Reliable Communications All physical systems have noise Electrons always vibrate at non-zero temperature Motion of electrons induces noise Presence of noise limits accuracy of measurement of received signal amplitude Errors occur if signal separation is comparable to noise level Bit Error Rate (BER) increases with decreasing signal-to-noise ratio Noise places a limit on how many amplitude levels can be used in pulse transmission 9 Digital Communication Basics Anish Goel
11. Shannon Channel Capacity C = Wclog2 (1 + SNR) bps Arbitrarily reliable communications is possible if the transmission rate R < C. If R > C, then arbitrarily reliable communications is not possible. “Arbitrarily reliable” means the BER can be made arbitrarily small through sufficiently complex coding. C can be used as a measure of how close a system design is to the best achievable performance. Bandwidth Wc & SNR determine C 11 Digital Communication Basics Anish Goel
12. Digitization of Analog Signals Sampling: obtain samples of x(t) at uniformly spaced time intervals Quantization: map each sample into an approximation value of finite precision Pulse Code Modulation: telephone speech CD audio Compression: to lower bit rate further, apply additional compression method Differential coding: cellular telephone speech Subband coding: MP3 audio 12 Digital Communication Basics Anish Goel
16. Error Control Digital transmission systems introduce errors Applications require certain reliability level Data applications require error-free transfer Voice & video applications tolerate some errors Error control used when transmission system does not meet application requirement Error control ensures a data stream is transmitted to a certain level of accuracy despite errors Two basic approaches: Error detection & retransmission (ARQ) Forward error correction (FEC) 16 Digital Communication Basics Anish Goel
17. Key Idea All transmitted data blocks (“codewords”) satisfy a pattern If received block doesn’t satisfy pattern, it is in error Redundancy: Only a subset of all possible blocks can be codewords Blindspot: when channel transforms a codeword into another codeword 17 Digital Communication Basics Anish Goel