This document discusses digital communications systems and digital modulation schemes. It provides examples of digital transmission with and without an analog carrier. It also describes frequency shift keying (FSK) and binary FSK (BFSK), where digital information is transmitted by shifting the frequency of the carrier signal between two predetermined frequencies. FSK provides constant amplitude and phase but changes the frequency of the carrier signal based on the digital input.
The document outlines various digital modulation techniques including ASK, BPSK, and FSK. It describes how each technique generates and detects modulated signals. ASK encodes data in signal amplitude levels. BPSK uses two phase shift keying to encode bits. FSK encodes data by shifting the carrier frequency between two values. Optimum detection requires coherent demodulation that correlates the received signal with a reference carrier.
1. Pulse code modulation (PCM) is a method of digitizing analog signals by sampling the signal, quantizing the samples to a set of discrete levels, and encoding the results as digital data.
2. In PCM, an analog signal is sampled, quantized to a certain number of levels, and then encoded as binary digits. At the receiver, the digital signal is decoded, converting it back into an analog waveform.
3. Key aspects of PCM include sampling the analog signal, quantizing the samples to discrete levels, binary encoding the quantized samples, transmitting the encoded data, decoding the data back into quantized samples, and reconstructing the analog signal from the samples. PCM
This document discusses source coding and channel coding in communication systems. It defines source coding as the process of encoding source data, such as speech or text, into binary format before transmission. Channel coding adds redundancy to encoded data to detect and correct errors during transmission over a noisy communication channel. Common source coding techniques discussed include Huffman coding and Lempel-Ziv algorithms, while channel coding includes block codes and convolution codes. Entropy, mutual information, and other information theory concepts are also introduced.
Amplitude Shift Keying (ASK) is a modulation technique where the amplitude of a carrier signal is varied according to the amplitude levels of a digital signal. In ASK, a digital signal of 1s and 0s is multiplied with a carrier signal, with a 1 having no effect on the carrier signal but a 0 reducing the carrier signal amplitude to zero. ASK has high efficiency and low noise interference but also high bandwidth and power consumption, making it suitable for applications like satellite links.
This slide describe the techniques of digital modulation and Bandwidth Efficiency:
The first null bandwidth of M-ary PSK signals decrease as M increases while Rb is held constant.
Therefore, as the value of M increases, the bandwidth efficiency also increases.
1. Digital modulation techniques are used to modulate digital information so that it can be transmitted via different mediums. Common digital modulation methods include binary amplitude shift keying (ASK), frequency shift keying (FSK), and phase shift keying (PSK).
2. FSK conveys information by changing the instantaneous frequency of a carrier wave. It is less susceptible to errors than ASK but has a larger spectrum bandwidth. PSK varies the phase of the transmitted signal. BPSK uses two phases while QPSK uses four phases.
3. The performance of digital modulation techniques can be compared using the energy per bit to noise power spectral density ratio (Eb/N0). Lower Eb/N0 values
Hybrid radio combines broadcast radio with broadband/IP technologies. It allows for enriched content like on-demand listening and personalized content while maintaining the reliability and cost-effectiveness of traditional broadcast radio. The RadioDNS standard enables linking broadcast radio stations to their online content. The EBU has created free tools and services to help broadcasters set up hybrid radio services for their stations.
This document compares HD Radio, DRM, and DAB digital radio technologies. It summarizes that HD Radio operates in existing AM and FM bands, allowing it to reuse existing radio infrastructure and have lower implementation costs than DAB or DRM. HD Radio uses COFDM modulation like DAB and DRM. Its HDC audio codec provides near-CD quality at lower bitrates than the MP2 codec used for DAB. Overall, HD Radio is presented as having implementation and operational cost advantages over DAB and DRM due to operating in existing bands and reusing existing radio infrastructure.
The document outlines various digital modulation techniques including ASK, BPSK, and FSK. It describes how each technique generates and detects modulated signals. ASK encodes data in signal amplitude levels. BPSK uses two phase shift keying to encode bits. FSK encodes data by shifting the carrier frequency between two values. Optimum detection requires coherent demodulation that correlates the received signal with a reference carrier.
1. Pulse code modulation (PCM) is a method of digitizing analog signals by sampling the signal, quantizing the samples to a set of discrete levels, and encoding the results as digital data.
2. In PCM, an analog signal is sampled, quantized to a certain number of levels, and then encoded as binary digits. At the receiver, the digital signal is decoded, converting it back into an analog waveform.
3. Key aspects of PCM include sampling the analog signal, quantizing the samples to discrete levels, binary encoding the quantized samples, transmitting the encoded data, decoding the data back into quantized samples, and reconstructing the analog signal from the samples. PCM
This document discusses source coding and channel coding in communication systems. It defines source coding as the process of encoding source data, such as speech or text, into binary format before transmission. Channel coding adds redundancy to encoded data to detect and correct errors during transmission over a noisy communication channel. Common source coding techniques discussed include Huffman coding and Lempel-Ziv algorithms, while channel coding includes block codes and convolution codes. Entropy, mutual information, and other information theory concepts are also introduced.
Amplitude Shift Keying (ASK) is a modulation technique where the amplitude of a carrier signal is varied according to the amplitude levels of a digital signal. In ASK, a digital signal of 1s and 0s is multiplied with a carrier signal, with a 1 having no effect on the carrier signal but a 0 reducing the carrier signal amplitude to zero. ASK has high efficiency and low noise interference but also high bandwidth and power consumption, making it suitable for applications like satellite links.
This slide describe the techniques of digital modulation and Bandwidth Efficiency:
The first null bandwidth of M-ary PSK signals decrease as M increases while Rb is held constant.
Therefore, as the value of M increases, the bandwidth efficiency also increases.
1. Digital modulation techniques are used to modulate digital information so that it can be transmitted via different mediums. Common digital modulation methods include binary amplitude shift keying (ASK), frequency shift keying (FSK), and phase shift keying (PSK).
2. FSK conveys information by changing the instantaneous frequency of a carrier wave. It is less susceptible to errors than ASK but has a larger spectrum bandwidth. PSK varies the phase of the transmitted signal. BPSK uses two phases while QPSK uses four phases.
3. The performance of digital modulation techniques can be compared using the energy per bit to noise power spectral density ratio (Eb/N0). Lower Eb/N0 values
Hybrid radio combines broadcast radio with broadband/IP technologies. It allows for enriched content like on-demand listening and personalized content while maintaining the reliability and cost-effectiveness of traditional broadcast radio. The RadioDNS standard enables linking broadcast radio stations to their online content. The EBU has created free tools and services to help broadcasters set up hybrid radio services for their stations.
This document compares HD Radio, DRM, and DAB digital radio technologies. It summarizes that HD Radio operates in existing AM and FM bands, allowing it to reuse existing radio infrastructure and have lower implementation costs than DAB or DRM. HD Radio uses COFDM modulation like DAB and DRM. Its HDC audio codec provides near-CD quality at lower bitrates than the MP2 codec used for DAB. Overall, HD Radio is presented as having implementation and operational cost advantages over DAB and DRM due to operating in existing bands and reusing existing radio infrastructure.
2024 State of Marketing Report – by HubspotMarius Sescu
https://www.hubspot.com/state-of-marketing
· Scaling relationships and proving ROI
· Social media is the place for search, sales, and service
· Authentic influencer partnerships fuel brand growth
· The strongest connections happen via call, click, chat, and camera.
· Time saved with AI leads to more creative work
· Seeking: A single source of truth
· TLDR; Get on social, try AI, and align your systems.
· More human marketing, powered by robots
ChatGPT is a revolutionary addition to the world since its introduction in 2022. A big shift in the sector of information gathering and processing happened because of this chatbot. What is the story of ChatGPT? How is the bot responding to prompts and generating contents? Swipe through these slides prepared by Expeed Software, a web development company regarding the development and technical intricacies of ChatGPT!
Product Design Trends in 2024 | Teenage EngineeringsPixeldarts
The realm of product design is a constantly changing environment where technology and style intersect. Every year introduces fresh challenges and exciting trends that mold the future of this captivating art form. In this piece, we delve into the significant trends set to influence the look and functionality of product design in the year 2024.
How Race, Age and Gender Shape Attitudes Towards Mental HealthThinkNow
Mental health has been in the news quite a bit lately. Dozens of U.S. states are currently suing Meta for contributing to the youth mental health crisis by inserting addictive features into their products, while the U.S. Surgeon General is touring the nation to bring awareness to the growing epidemic of loneliness and isolation. The country has endured periods of low national morale, such as in the 1970s when high inflation and the energy crisis worsened public sentiment following the Vietnam War. The current mood, however, feels different. Gallup recently reported that national mental health is at an all-time low, with few bright spots to lift spirits.
To better understand how Americans are feeling and their attitudes towards mental health in general, ThinkNow conducted a nationally representative quantitative survey of 1,500 respondents and found some interesting differences among ethnic, age and gender groups.
Technology
For example, 52% agree that technology and social media have a negative impact on mental health, but when broken out by race, 61% of Whites felt technology had a negative effect, and only 48% of Hispanics thought it did.
While technology has helped us keep in touch with friends and family in faraway places, it appears to have degraded our ability to connect in person. Staying connected online is a double-edged sword since the same news feed that brings us pictures of the grandkids and fluffy kittens also feeds us news about the wars in Israel and Ukraine, the dysfunction in Washington, the latest mass shooting and the climate crisis.
Hispanics may have a built-in defense against the isolation technology breeds, owing to their large, multigenerational households, strong social support systems, and tendency to use social media to stay connected with relatives abroad.
Age and Gender
When asked how individuals rate their mental health, men rate it higher than women by 11 percentage points, and Baby Boomers rank it highest at 83%, saying it’s good or excellent vs. 57% of Gen Z saying the same.
Gen Z spends the most amount of time on social media, so the notion that social media negatively affects mental health appears to be correlated. Unfortunately, Gen Z is also the generation that’s least comfortable discussing mental health concerns with healthcare professionals. Only 40% of them state they’re comfortable discussing their issues with a professional compared to 60% of Millennials and 65% of Boomers.
Race Affects Attitudes
As seen in previous research conducted by ThinkNow, Asian Americans lag other groups when it comes to awareness of mental health issues. Twenty-four percent of Asian Americans believe that having a mental health issue is a sign of weakness compared to the 16% average for all groups. Asians are also considerably less likely to be aware of mental health services in their communities (42% vs. 55%) and most likely to seek out information on social media (51% vs. 35%).
AI Trends in Creative Operations 2024 by Artwork Flow.pdfmarketingartwork
Creative operations teams expect increased AI use in 2024. Currently, over half of tasks are not AI-enabled, but this is expected to decrease in the coming year. ChatGPT is the most popular AI tool currently. Business leaders are more actively exploring AI benefits than individual contributors. Most respondents do not believe AI will impact workforce size in 2024. However, some inhibitions still exist around AI accuracy and lack of understanding. Creatives primarily want to use AI to save time on mundane tasks and boost productivity.
Organizational culture includes values, norms, systems, symbols, language, assumptions, beliefs, and habits that influence employee behaviors and how people interpret those behaviors. It is important because culture can help or hinder a company's success. Some key aspects of Netflix's culture that help it achieve results include hiring smartly so every position has stars, focusing on attitude over just aptitude, and having a strict policy against peacocks, whiners, and jerks.
PEPSICO Presentation to CAGNY Conference Feb 2024Neil Kimberley
PepsiCo provided a safe harbor statement noting that any forward-looking statements are based on currently available information and are subject to risks and uncertainties. It also provided information on non-GAAP measures and directing readers to its website for disclosure and reconciliation. The document then discussed PepsiCo's business overview, including that it is a global beverage and convenient food company with iconic brands, $91 billion in net revenue in 2023, and nearly $14 billion in core operating profit. It operates through a divisional structure with a focus on local consumers.
Content Methodology: A Best Practices Report (Webinar)contently
This document provides an overview of content methodology best practices. It defines content methodology as establishing objectives, KPIs, and a culture of continuous learning and iteration. An effective methodology focuses on connecting with audiences, creating optimal content, and optimizing processes. It also discusses why a methodology is needed due to the competitive landscape, proliferation of channels, and opportunities for improvement. Components of an effective methodology include defining objectives and KPIs, audience analysis, identifying opportunities, and evaluating resources. The document concludes with recommendations around creating a content plan, testing and optimizing content over 90 days.
How to Prepare For a Successful Job Search for 2024Albert Qian
The document provides guidance on preparing a job search for 2024. It discusses the state of the job market, focusing on growth in AI and healthcare but also continued layoffs. It recommends figuring out what you want to do by researching interests and skills, then conducting informational interviews. The job search should involve building a personal brand on LinkedIn, actively applying to jobs, tailoring resumes and interviews, maintaining job hunting as a habit, and continuing self-improvement. Once hired, the document advises setting new goals and keeping skills and networking active in case of future opportunities.
A report by thenetworkone and Kurio.
The contributing experts and agencies are (in an alphabetical order): Sylwia Rytel, Social Media Supervisor, 180heartbeats + JUNG v MATT (PL), Sharlene Jenner, Vice President - Director of Engagement Strategy, Abelson Taylor (USA), Alex Casanovas, Digital Director, Atrevia (ES), Dora Beilin, Senior Social Strategist, Barrett Hoffher (USA), Min Seo, Campaign Director, Brand New Agency (KR), Deshé M. Gully, Associate Strategist, Day One Agency (USA), Francesca Trevisan, Strategist, Different (IT), Trevor Crossman, CX and Digital Transformation Director; Olivia Hussey, Strategic Planner; Simi Srinarula, Social Media Manager, The Hallway (AUS), James Hebbert, Managing Director, Hylink (CN / UK), Mundy Álvarez, Planning Director; Pedro Rojas, Social Media Manager; Pancho González, CCO, Inbrax (CH), Oana Oprea, Head of Digital Planning, Jam Session Agency (RO), Amy Bottrill, Social Account Director, Launch (UK), Gaby Arriaga, Founder, Leonardo1452 (MX), Shantesh S Row, Creative Director, Liwa (UAE), Rajesh Mehta, Chief Strategy Officer; Dhruv Gaur, Digital Planning Lead; Leonie Mergulhao, Account Supervisor - Social Media & PR, Medulla (IN), Aurelija Plioplytė, Head of Digital & Social, Not Perfect (LI), Daiana Khaidargaliyeva, Account Manager, Osaka Labs (UK / USA), Stefanie Söhnchen, Vice President Digital, PIABO Communications (DE), Elisabeth Winiartati, Managing Consultant, Head of Global Integrated Communications; Lydia Aprina, Account Manager, Integrated Marketing and Communications; Nita Prabowo, Account Manager, Integrated Marketing and Communications; Okhi, Web Developer, PNTR Group (ID), Kei Obusan, Insights Director; Daffi Ranandi, Insights Manager, Radarr (SG), Gautam Reghunath, Co-founder & CEO, Talented (IN), Donagh Humphreys, Head of Social and Digital Innovation, THINKHOUSE (IRE), Sarah Yim, Strategy Director, Zulu Alpha Kilo (CA).
Trends In Paid Search: Navigating The Digital Landscape In 2024Search Engine Journal
The search marketing landscape is evolving rapidly with new technologies, and professionals, like you, rely on innovative paid search strategies to meet changing demands.
It’s important that you’re ready to implement new strategies in 2024.
Check this out and learn the top trends in paid search advertising that are expected to gain traction, so you can drive higher ROI more efficiently in 2024.
You’ll learn:
- The latest trends in AI and automation, and what this means for an evolving paid search ecosystem.
- New developments in privacy and data regulation.
- Emerging ad formats that are expected to make an impact next year.
Watch Sreekant Lanka from iQuanti and Irina Klein from OneMain Financial as they dive into the future of paid search and explore the trends, strategies, and technologies that will shape the search marketing landscape.
If you’re looking to assess your paid search strategy and design an industry-aligned plan for 2024, then this webinar is for you.
5 Public speaking tips from TED - Visualized summarySpeakerHub
From their humble beginnings in 1984, TED has grown into the world’s most powerful amplifier for speakers and thought-leaders to share their ideas. They have over 2,400 filmed talks (not including the 30,000+ TEDx videos) freely available online, and have hosted over 17,500 events around the world.
With over one billion views in a year, it’s no wonder that so many speakers are looking to TED for ideas on how to share their message more effectively.
The article “5 Public-Speaking Tips TED Gives Its Speakers”, by Carmine Gallo for Forbes, gives speakers five practical ways to connect with their audience, and effectively share their ideas on stage.
Whether you are gearing up to get on a TED stage yourself, or just want to master the skills that so many of their speakers possess, these tips and quotes from Chris Anderson, the TED Talks Curator, will encourage you to make the most impactful impression on your audience.
See the full article and more summaries like this on SpeakerHub here: https://speakerhub.com/blog/5-presentation-tips-ted-gives-its-speakers
See the original article on Forbes here:
http://www.forbes.com/forbes/welcome/?toURL=http://www.forbes.com/sites/carminegallo/2016/05/06/5-public-speaking-tips-ted-gives-its-speakers/&refURL=&referrer=#5c07a8221d9b
ChatGPT and the Future of Work - Clark Boyd Clark Boyd
Everyone is in agreement that ChatGPT (and other generative AI tools) will shape the future of work. Yet there is little consensus on exactly how, when, and to what extent this technology will change our world.
Businesses that extract maximum value from ChatGPT will use it as a collaborative tool for everything from brainstorming to technical maintenance.
For individuals, now is the time to pinpoint the skills the future professional will need to thrive in the AI age.
Check out this presentation to understand what ChatGPT is, how it will shape the future of work, and how you can prepare to take advantage.
The document provides career advice for getting into the tech field, including:
- Doing projects and internships in college to build a portfolio.
- Learning about different roles and technologies through industry research.
- Contributing to open source projects to build experience and network.
- Developing a personal brand through a website and social media presence.
- Networking through events, communities, and finding a mentor.
- Practicing interviews through mock interviews and whiteboarding coding questions.
Google's Just Not That Into You: Understanding Core Updates & Search IntentLily Ray
1. Core updates from Google periodically change how its algorithms assess and rank websites and pages. This can impact rankings through shifts in user intent, site quality issues being caught up to, world events influencing queries, and overhauls to search like the E-A-T framework.
2. There are many possible user intents beyond just transactional, navigational and informational. Identifying intent shifts is important during core updates. Sites may need to optimize for new intents through different content types and sections.
3. Responding effectively to core updates requires analyzing "before and after" data to understand changes, identifying new intents or page types, and ensuring content matches appropriate intents across video, images, knowledge graphs and more.
A brief introduction to DataScience with explaining of the concepts, algorithms, machine learning, supervised and unsupervised learning, clustering, statistics, data preprocessing, real-world applications etc.
It's part of a Data Science Corner Campaign where I will be discussing the fundamentals of DataScience, AIML, Statistics etc.
Time Management & Productivity - Best PracticesVit Horky
Here's my presentation on by proven best practices how to manage your work time effectively and how to improve your productivity. It includes practical tips and how to use tools such as Slack, Google Apps, Hubspot, Google Calendar, Gmail and others.
The six step guide to practical project managementMindGenius
The six step guide to practical project management
If you think managing projects is too difficult, think again.
We’ve stripped back project management processes to the
basics – to make it quicker and easier, without sacrificing
the vital ingredients for success.
“If you’re looking for some real-world guidance, then The Six Step Guide to Practical Project Management will help.”
Dr Andrew Makar, Tactical Project Management
2024 State of Marketing Report – by HubspotMarius Sescu
https://www.hubspot.com/state-of-marketing
· Scaling relationships and proving ROI
· Social media is the place for search, sales, and service
· Authentic influencer partnerships fuel brand growth
· The strongest connections happen via call, click, chat, and camera.
· Time saved with AI leads to more creative work
· Seeking: A single source of truth
· TLDR; Get on social, try AI, and align your systems.
· More human marketing, powered by robots
ChatGPT is a revolutionary addition to the world since its introduction in 2022. A big shift in the sector of information gathering and processing happened because of this chatbot. What is the story of ChatGPT? How is the bot responding to prompts and generating contents? Swipe through these slides prepared by Expeed Software, a web development company regarding the development and technical intricacies of ChatGPT!
Product Design Trends in 2024 | Teenage EngineeringsPixeldarts
The realm of product design is a constantly changing environment where technology and style intersect. Every year introduces fresh challenges and exciting trends that mold the future of this captivating art form. In this piece, we delve into the significant trends set to influence the look and functionality of product design in the year 2024.
How Race, Age and Gender Shape Attitudes Towards Mental HealthThinkNow
Mental health has been in the news quite a bit lately. Dozens of U.S. states are currently suing Meta for contributing to the youth mental health crisis by inserting addictive features into their products, while the U.S. Surgeon General is touring the nation to bring awareness to the growing epidemic of loneliness and isolation. The country has endured periods of low national morale, such as in the 1970s when high inflation and the energy crisis worsened public sentiment following the Vietnam War. The current mood, however, feels different. Gallup recently reported that national mental health is at an all-time low, with few bright spots to lift spirits.
To better understand how Americans are feeling and their attitudes towards mental health in general, ThinkNow conducted a nationally representative quantitative survey of 1,500 respondents and found some interesting differences among ethnic, age and gender groups.
Technology
For example, 52% agree that technology and social media have a negative impact on mental health, but when broken out by race, 61% of Whites felt technology had a negative effect, and only 48% of Hispanics thought it did.
While technology has helped us keep in touch with friends and family in faraway places, it appears to have degraded our ability to connect in person. Staying connected online is a double-edged sword since the same news feed that brings us pictures of the grandkids and fluffy kittens also feeds us news about the wars in Israel and Ukraine, the dysfunction in Washington, the latest mass shooting and the climate crisis.
Hispanics may have a built-in defense against the isolation technology breeds, owing to their large, multigenerational households, strong social support systems, and tendency to use social media to stay connected with relatives abroad.
Age and Gender
When asked how individuals rate their mental health, men rate it higher than women by 11 percentage points, and Baby Boomers rank it highest at 83%, saying it’s good or excellent vs. 57% of Gen Z saying the same.
Gen Z spends the most amount of time on social media, so the notion that social media negatively affects mental health appears to be correlated. Unfortunately, Gen Z is also the generation that’s least comfortable discussing mental health concerns with healthcare professionals. Only 40% of them state they’re comfortable discussing their issues with a professional compared to 60% of Millennials and 65% of Boomers.
Race Affects Attitudes
As seen in previous research conducted by ThinkNow, Asian Americans lag other groups when it comes to awareness of mental health issues. Twenty-four percent of Asian Americans believe that having a mental health issue is a sign of weakness compared to the 16% average for all groups. Asians are also considerably less likely to be aware of mental health services in their communities (42% vs. 55%) and most likely to seek out information on social media (51% vs. 35%).
AI Trends in Creative Operations 2024 by Artwork Flow.pdfmarketingartwork
Creative operations teams expect increased AI use in 2024. Currently, over half of tasks are not AI-enabled, but this is expected to decrease in the coming year. ChatGPT is the most popular AI tool currently. Business leaders are more actively exploring AI benefits than individual contributors. Most respondents do not believe AI will impact workforce size in 2024. However, some inhibitions still exist around AI accuracy and lack of understanding. Creatives primarily want to use AI to save time on mundane tasks and boost productivity.
Organizational culture includes values, norms, systems, symbols, language, assumptions, beliefs, and habits that influence employee behaviors and how people interpret those behaviors. It is important because culture can help or hinder a company's success. Some key aspects of Netflix's culture that help it achieve results include hiring smartly so every position has stars, focusing on attitude over just aptitude, and having a strict policy against peacocks, whiners, and jerks.
PEPSICO Presentation to CAGNY Conference Feb 2024Neil Kimberley
PepsiCo provided a safe harbor statement noting that any forward-looking statements are based on currently available information and are subject to risks and uncertainties. It also provided information on non-GAAP measures and directing readers to its website for disclosure and reconciliation. The document then discussed PepsiCo's business overview, including that it is a global beverage and convenient food company with iconic brands, $91 billion in net revenue in 2023, and nearly $14 billion in core operating profit. It operates through a divisional structure with a focus on local consumers.
Content Methodology: A Best Practices Report (Webinar)contently
This document provides an overview of content methodology best practices. It defines content methodology as establishing objectives, KPIs, and a culture of continuous learning and iteration. An effective methodology focuses on connecting with audiences, creating optimal content, and optimizing processes. It also discusses why a methodology is needed due to the competitive landscape, proliferation of channels, and opportunities for improvement. Components of an effective methodology include defining objectives and KPIs, audience analysis, identifying opportunities, and evaluating resources. The document concludes with recommendations around creating a content plan, testing and optimizing content over 90 days.
How to Prepare For a Successful Job Search for 2024Albert Qian
The document provides guidance on preparing a job search for 2024. It discusses the state of the job market, focusing on growth in AI and healthcare but also continued layoffs. It recommends figuring out what you want to do by researching interests and skills, then conducting informational interviews. The job search should involve building a personal brand on LinkedIn, actively applying to jobs, tailoring resumes and interviews, maintaining job hunting as a habit, and continuing self-improvement. Once hired, the document advises setting new goals and keeping skills and networking active in case of future opportunities.
A report by thenetworkone and Kurio.
The contributing experts and agencies are (in an alphabetical order): Sylwia Rytel, Social Media Supervisor, 180heartbeats + JUNG v MATT (PL), Sharlene Jenner, Vice President - Director of Engagement Strategy, Abelson Taylor (USA), Alex Casanovas, Digital Director, Atrevia (ES), Dora Beilin, Senior Social Strategist, Barrett Hoffher (USA), Min Seo, Campaign Director, Brand New Agency (KR), Deshé M. Gully, Associate Strategist, Day One Agency (USA), Francesca Trevisan, Strategist, Different (IT), Trevor Crossman, CX and Digital Transformation Director; Olivia Hussey, Strategic Planner; Simi Srinarula, Social Media Manager, The Hallway (AUS), James Hebbert, Managing Director, Hylink (CN / UK), Mundy Álvarez, Planning Director; Pedro Rojas, Social Media Manager; Pancho González, CCO, Inbrax (CH), Oana Oprea, Head of Digital Planning, Jam Session Agency (RO), Amy Bottrill, Social Account Director, Launch (UK), Gaby Arriaga, Founder, Leonardo1452 (MX), Shantesh S Row, Creative Director, Liwa (UAE), Rajesh Mehta, Chief Strategy Officer; Dhruv Gaur, Digital Planning Lead; Leonie Mergulhao, Account Supervisor - Social Media & PR, Medulla (IN), Aurelija Plioplytė, Head of Digital & Social, Not Perfect (LI), Daiana Khaidargaliyeva, Account Manager, Osaka Labs (UK / USA), Stefanie Söhnchen, Vice President Digital, PIABO Communications (DE), Elisabeth Winiartati, Managing Consultant, Head of Global Integrated Communications; Lydia Aprina, Account Manager, Integrated Marketing and Communications; Nita Prabowo, Account Manager, Integrated Marketing and Communications; Okhi, Web Developer, PNTR Group (ID), Kei Obusan, Insights Director; Daffi Ranandi, Insights Manager, Radarr (SG), Gautam Reghunath, Co-founder & CEO, Talented (IN), Donagh Humphreys, Head of Social and Digital Innovation, THINKHOUSE (IRE), Sarah Yim, Strategy Director, Zulu Alpha Kilo (CA).
Trends In Paid Search: Navigating The Digital Landscape In 2024Search Engine Journal
The search marketing landscape is evolving rapidly with new technologies, and professionals, like you, rely on innovative paid search strategies to meet changing demands.
It’s important that you’re ready to implement new strategies in 2024.
Check this out and learn the top trends in paid search advertising that are expected to gain traction, so you can drive higher ROI more efficiently in 2024.
You’ll learn:
- The latest trends in AI and automation, and what this means for an evolving paid search ecosystem.
- New developments in privacy and data regulation.
- Emerging ad formats that are expected to make an impact next year.
Watch Sreekant Lanka from iQuanti and Irina Klein from OneMain Financial as they dive into the future of paid search and explore the trends, strategies, and technologies that will shape the search marketing landscape.
If you’re looking to assess your paid search strategy and design an industry-aligned plan for 2024, then this webinar is for you.
5 Public speaking tips from TED - Visualized summarySpeakerHub
From their humble beginnings in 1984, TED has grown into the world’s most powerful amplifier for speakers and thought-leaders to share their ideas. They have over 2,400 filmed talks (not including the 30,000+ TEDx videos) freely available online, and have hosted over 17,500 events around the world.
With over one billion views in a year, it’s no wonder that so many speakers are looking to TED for ideas on how to share their message more effectively.
The article “5 Public-Speaking Tips TED Gives Its Speakers”, by Carmine Gallo for Forbes, gives speakers five practical ways to connect with their audience, and effectively share their ideas on stage.
Whether you are gearing up to get on a TED stage yourself, or just want to master the skills that so many of their speakers possess, these tips and quotes from Chris Anderson, the TED Talks Curator, will encourage you to make the most impactful impression on your audience.
See the full article and more summaries like this on SpeakerHub here: https://speakerhub.com/blog/5-presentation-tips-ted-gives-its-speakers
See the original article on Forbes here:
http://www.forbes.com/forbes/welcome/?toURL=http://www.forbes.com/sites/carminegallo/2016/05/06/5-public-speaking-tips-ted-gives-its-speakers/&refURL=&referrer=#5c07a8221d9b
ChatGPT and the Future of Work - Clark Boyd Clark Boyd
Everyone is in agreement that ChatGPT (and other generative AI tools) will shape the future of work. Yet there is little consensus on exactly how, when, and to what extent this technology will change our world.
Businesses that extract maximum value from ChatGPT will use it as a collaborative tool for everything from brainstorming to technical maintenance.
For individuals, now is the time to pinpoint the skills the future professional will need to thrive in the AI age.
Check out this presentation to understand what ChatGPT is, how it will shape the future of work, and how you can prepare to take advantage.
The document provides career advice for getting into the tech field, including:
- Doing projects and internships in college to build a portfolio.
- Learning about different roles and technologies through industry research.
- Contributing to open source projects to build experience and network.
- Developing a personal brand through a website and social media presence.
- Networking through events, communities, and finding a mentor.
- Practicing interviews through mock interviews and whiteboarding coding questions.
Google's Just Not That Into You: Understanding Core Updates & Search IntentLily Ray
1. Core updates from Google periodically change how its algorithms assess and rank websites and pages. This can impact rankings through shifts in user intent, site quality issues being caught up to, world events influencing queries, and overhauls to search like the E-A-T framework.
2. There are many possible user intents beyond just transactional, navigational and informational. Identifying intent shifts is important during core updates. Sites may need to optimize for new intents through different content types and sections.
3. Responding effectively to core updates requires analyzing "before and after" data to understand changes, identifying new intents or page types, and ensuring content matches appropriate intents across video, images, knowledge graphs and more.
A brief introduction to DataScience with explaining of the concepts, algorithms, machine learning, supervised and unsupervised learning, clustering, statistics, data preprocessing, real-world applications etc.
It's part of a Data Science Corner Campaign where I will be discussing the fundamentals of DataScience, AIML, Statistics etc.
Time Management & Productivity - Best PracticesVit Horky
Here's my presentation on by proven best practices how to manage your work time effectively and how to improve your productivity. It includes practical tips and how to use tools such as Slack, Google Apps, Hubspot, Google Calendar, Gmail and others.
The six step guide to practical project managementMindGenius
The six step guide to practical project management
If you think managing projects is too difficult, think again.
We’ve stripped back project management processes to the
basics – to make it quicker and easier, without sacrificing
the vital ingredients for success.
“If you’re looking for some real-world guidance, then The Six Step Guide to Practical Project Management will help.”
Dr Andrew Makar, Tactical Project Management
2. H TH NG TRUY N THÔNG S
• TRUY N THÔNG S – H TH NG S TH C S :
CÁC XUNG S (i.e. NRZ, AMI, MANCHESTER,HDB3) TRUY N QUA
CÁP ð NG/QUANG (KHÔNG SÓNG MANG TƯƠNG T ). THÔNG TIN
CÓ TH BAO G M S VÀ TƯƠNG T (C N A/D và D/A).
H TH NG TRUY N THÔNG S
11/14/2012 2
CÓ TH BAO G M S VÀ TƯƠNG T (C N A/D và D/A).
• CAO T N S (DIGITAL RADIO):
SÓNG MANG TƯƠNG T ðƯ C ðI U CH D NG S (i.e. PAM, QAM,
ASK, PSK, FSK, PWM). TRUY N THÔNG QUA CÁP ð NG HO C CÁP
QUANG HAY KHÔNG GIAN
3. DUNG LƯ NG KÊNH TRUY N/THÔNG TIN
HARTLEY’S LAW (BELL LABS)
DUNG LƯ NG KÊNH TRUY N LÀ HÀM TUY N TÍNH:
ðO XEM CÓ BAO NHIÊU THÔNG TIN (i.e. S M U ð C L P)
CÓ TH TRUY N QUA M T KÊNH TRUY N TRONG M T ðƠN V
TH I GIAN
11/14/2012 3
DUNG LƯ NG KÊNH TRUY N LÀ HÀM TUY N TÍNH:
txBC ∝
C: DUNG LƯ NG KÊNH TRUY N
B: BĂNG THÔNG (Hz)
t: TH I GIAN TRUY N (secs)
4. V I 1 KÊNH TRUY N CÓ NHI U, T S TÍN Hi U TRÊN NHI U (S/N) LÀ T S
C A CÔNG SU T TÍN HI U TRÊN CÔNG SU T NHI U, ðƯ C ðO ð U THU
M I QUAN H C A BĂNG THÔNG VÀ DUNG LƯ NG
KÊNH
=
PowerNoise
PowerSignal
NS dB log10)/(
11/14/2012 4
)1(log 2
N
S
BC +=
C: DUNG LƯ NG KÊNH TRUY N (bps) / BIT RATE
B: BĂNG THÔNG (Hz)
S/N: T S TÍN HI U TRÊN NHI U
)1(log 2
N
S
C
B
+
=
SHANNON’S THEOREM (BELL LABS)
5. DUNG LƯ NG KÊNH
VÍ D
DÙNG 1 KÊNH THO I ð TRUY N D Li U S QUA MODEM.
B = 3100Hz, S/N = 30 dB = ratio of 1000:1
bps
N
S
BC 894,30)10001(log3100)1(log 22 =+=+=
11/14/2012 5
T C ð BIT NÀY CH LÀ T I ðA THEO LÝ THUY T.
NÓ KHÔNG TH ð T ð N V I MÃ HÓA NH PHÂN.
• GI NGUYÊN CÁC GIÁ TR KHÁC, TĂNG BĂNG THÔNG
S TĂNG T C ð D LI U.
6. BAUD RATE Vs BIT RATE
BIT RATE = S LƯ NG BIT M I GIÂY (BIT = MOST BASIC SYMBOL)
BAUD RATE = S LƯ NG M U (SYMBOLS) M I PER SECOND.
USING MULTI-LEVEL ENCODING SCHEMES ARE NEEDED TO ACHIEVE THE SHANNON
LIMIT.
TRANSMISSION OF M SIGNAL SYMBOLS, N BITS EACH.
N
M 2=
11/14/2012 6
• EXAMPLE: 2-LEVEL BINARY SYSTEM: M = 2, N = 1. ONE SIGNAL SYMBOL = 1 BIT.
TRANSMISSION OF 1 SIGNAL SYMBOL = TRANSMISSION OF 1 BIT.
(BAUD RATE = BIT RATE)
• EXAMPLE: 16-QAM. M = 16, N = 4. ONE SIGNAL SYMBOL = 4 BITS.
TRANSMISSION OF 1 SIGNAL SYMBOL = TRANSMISSION OF 4 BITS.
THUS, 9600 BPS = 2400 BAUDS.
7. COMMUNICATIONS SYSTEMS EXAMPLES
DIGITAL TRANSMISSIONDIGITAL TRANSMISSION
NO ANALOG CARRIERNO ANALOG CARRIER
TRUE DIGITAL SYSTEM:TRUE DIGITAL SYSTEM:
11/14/2012 7
DIGITAL TRANSMISSIONDIGITAL TRANSMISSION
DIGITAL RADIODIGITAL RADIO
ANALOG CARRIERANALOG CARRIER
8. CAO T N S (DIGITAL RADIO):CAO T N S (DIGITAL RADIO):
•• THÔNG TIN CÓ TH LÀ TƯƠNG TTHÔNG TIN CÓ TH LÀ TƯƠNG T Ho CHo C SS
11/14/2012 8
•• ði Uði U CH SCH S ::
•• TÍNTÍN Hi UHi U ði Uði U CH D NG SCH D NG S
•• SÓNG MANG D NG TƯƠNG TSÓNG MANG D NG TƯƠNG T
9. H TH NG CAO T N SH TH NG CAO T N S
11/14/2012 9
ENCODERENCODER
PHASE LOCKED LOOPPHASE LOCKED LOOP
CLOCKS HAVE TO BE SYNCHRONIZEDCLOCKS HAVE TO BE SYNCHRONIZED
12. ðI U CH BIÊN ð S (OOK, ASK)ðI U CH BIÊN ð S (OOK, ASK)
•• K THU T ðI U CH S ðƠN GI N NH TK THU T ðI U CH S ðƠN GI N NH T
•• LÀ SÓNG LIÊN T C (CM), SINCELÀ SÓNG LIÊN T C (CM), SINCE
SÓNG MANG TRUY N (‘1’) CÓ BIÊN ð , T N SSÓNG MANG TRUY N (‘1’) CÓ BIÊN ð , T N S
VÀ PHA C ð NHVÀ PHA C ð NH
•• DSBDSB--FC AM WAVE: TÍN HI U ðI U CH NGÕ VÀOFC AM WAVE: TÍN HI U ðI U CH NGÕ VÀO
11/14/2012 12
•• DSBDSB--FC AM WAVE: TÍN HI U ðI U CH NGÕ VÀOFC AM WAVE: TÍN HI U ðI U CH NGÕ VÀO
LÀ D NG NH PHÂNLÀ D NG NH PHÂN
•• K THU T ðI U CH CHI PHÍ TH P, CH T LƯ NGK THU T ðI U CH CHI PHÍ TH P, CH T LƯ NG
TH P, HI U SU T TH PTH P, HI U SU T TH P
•• HI M KHI ðƯ C S D NG TRONG H TH NG HI UHI M KHI ðƯ C S D NG TRONG H TH NG HI U
SU T VÀ DUNG LƯ NG CAOSU T VÀ DUNG LƯ NG CAO
13. ðI U CH BIÊN ð SðI U CH BIÊN ð S
BINARY INPUTBINARY INPUT
(BASEBAND SIGNAL)(BASEBAND SIGNAL)tbtb tbtb
11/14/2012 13
ONON--OFF KEYINGOFF KEYING
MODULATIONMODULATION
(OOK, ASK)(OOK, ASK)
tb = BIT TIMEtb = BIT TIME
1/tb = fb=BIT RATE1/tb = fb=BIT RATE
14. DIGITALAMPLITUDE MODULATIONDIGITALAMPLITUDE MODULATION
[ ] )cos(
2
)(1)( t
V
tvtv c
c
mam ω+=
=+ 1log1 icalV
)cos(
2
)()cos(
2
)( t
V
tvt
V
tv c
c
mc
c
am ωω +=
11/14/2012 14
=−
=+
=
0log1
1log1
)(
icalV
icalV
tvm
=
inputical
inputicaltV
tv
cc
am
0log;0
1log);cos(
)(
ω
NORMALIZEDNORMALIZED
INPUT SIGNALINPUT SIGNAL
17. FREQUENCY SHIFT KEYING (FSK, BFSK)FREQUENCY SHIFT KEYING (FSK, BFSK)
•• K THU T ðI U CH S ðƠN GI NK THU T ðI U CH S ðƠN GI N
•• K THU T ðI U CH CHI PHÍ TH P, HI U SU T TH PK THU T ðI U CH CHI PHÍ TH P, HI U SU T TH P
•• BFSK TƯƠNG T NHƯ FM (CONSTANT AMPLITUDE/BFSK TƯƠNG T NHƯ FM (CONSTANT AMPLITUDE/
PHASE) NGO I TR TÍN HI U ðI U CH LÀ NH PHÂNPHASE) NGO I TR TÍN HI U ðI U CH LÀ NH PHÂN
(THAY ð I GI A 2 M C RIÊNG BI T)(THAY ð I GI A 2 M C RIÊNG BI T)
11/14/2012 17
(THAY ð I GI A 2 M C RIÊNG BI T)(THAY ð I GI A 2 M C RIÊNG BI T)
•• BFSK HI M KHI ðƯ C S D NG TRONG H TH NGBFSK HI M KHI ðƯ C S D NG TRONG H TH NG
S HI U SU T CAO. S D NG H N CH TRONGS HI U SU T CAO. S D NG H N CH TRONG
MODEM B T ð NG B HI U SU T TH P, CHI PHÍMODEM B T ð NG B HI U SU T TH P, CHI PHÍ
TH P DÙNG ð TRUY N D LI U QUA ðƯ NG DÂYTH P DÙNG ð TRUY N D LI U QUA ðƯ NG DÂY
THO I TƯƠNG T .THO I TƯƠNG T .
18. FREQUENCY SHIFT KEYING (FSK, BFSK)FREQUENCY SHIFT KEYING (FSK, BFSK)
{ }[ ]tftvfVtv mccfsk ∆+= )(2cos)( π
≡
≡∆
≡
c
c
V
f
f T N S SÓNG MANG TRUNG TÂMT N S SÓNG MANG TRUNG TÂM
ð L CH T N S ð NHð L CH T N S ð NH
BIÊN ð SÓNG MANG ð NHBIÊN ð SÓNG MANG ð NH
11/14/2012 18
=−
=+
=
0log1
1log1
)(
icalV
icalV
tvm
NORMALIZEDNORMALIZED
INPUT SIGNALINPUT SIGNAL
{ }[ ]
{ }[ ]
∆−
∆+
=
inputicaltffV
inputicaltffV
tv
cc
cc
fsk
0log;2cos
1log;2cos
)(
π
π
19. FREQUENCY SHIFT KEYING (FSK, BFSK)FREQUENCY SHIFT KEYING (FSK, BFSK)
•• V I BPSK, T N S SÓNG MANG B D CH B I TÍNV I BPSK, T N S SÓNG MANG B D CH B I TÍN Hi UHi U NHNH
PHÂN NGÕ VÀOPHÂN NGÕ VÀO
fcm ff ∆+≡•
MARKMARK FREQUENCY = T N S NGÕ RA V IFREQUENCY = T N S NGÕ RA V I
LOGIC 1 NGÕ VÀOLOGIC 1 NGÕ VÀO
(SHIFT UP)(SHIFT UP)
11/14/2012 19
LOGIC 1 NGÕ VÀOLOGIC 1 NGÕ VÀO
SPACESPACE FREQUENCY = T N S NGÕ RA V IFREQUENCY = T N S NGÕ RA V I
LOGIC 0 NGÕ VÀOLOGIC 0 NGÕ VÀO
fcs ff ∆−≡• (SHIFT DOWN)(SHIFT DOWN)
sm ff ,• GIÁ TR D A VÀO THI T K H TH NGGIÁ TR D A VÀO THI T K H TH NG
21. FREQUENCY SHIFT KEYING (FSK, BFSK)FREQUENCY SHIFT KEYING (FSK, BFSK)
2 tb2 tb
tb = BIT TIMEtb = BIT TIME
1/tb = fb=BIT RATE1/tb = fb=BIT RATE
11/14/2012 21
1/2tb =1/2tb =
22. FREQUENCY SHIFT KEYING (FSK, BFSK)FREQUENCY SHIFT KEYING (FSK, BFSK)
•• V I BFSK, T C ð NGÕ RA B NG T C ð NGÕ VÀOV I BFSK, T C ð NGÕ RA B NG T C ð NGÕ VÀO
(T N S NGÕ RA THAY ð I M I L N M C LOGIC(T N S NGÕ RA THAY ð I M I L N M C LOGIC
NGÕ VÀO THAY ð I)NGÕ VÀO THAY ð I)
•• V I BFSK, T C ð BIT B NG V I T C ð BAUDV I BFSK, T C ð BIT B NG V I T C ð BAUD
(A SIGNAL SYMBOL = A BIT)(A SIGNAL SYMBOL = A BIT)
11/14/2012 22
(A SIGNAL SYMBOL = A BIT)(A SIGNAL SYMBOL = A BIT)
•• BB ði Uði U CH FSK THƯ NG LÀ 1 VCO V I 1 T N SCH FSK THƯ NG LÀ 1 VCO V I 1 T N S
TRUNG TÂM:TRUNG TÂM:
2
sm
osc
ff
f
−
=
mosc ffinput →:'1'
sosc ffinput →:'0'}
24. FREQUENCY SHIFT KEYING (FSK, BFSK)FREQUENCY SHIFT KEYING (FSK, BFSK)
)(ωI
INPUT
SIGNAL
MODULATED SIGNAL
0 bt/1bt/1−
b
b
f
t
=
1
11/14/2012 24
)(ωϑ
MODULATED SIGNAL
mf0 sf cf
b
m
t
f
1
+b
s
t
f
1
−
SIN X/XSIN X/X
(PULSED SINUSOIDAL WAVES)(PULSED SINUSOIDAL WAVES)
BB
25. FREQUENCY SHIFT KEYING (FSK, BFSK)FREQUENCY SHIFT KEYING (FSK, BFSK)
22
2)(
)()(
b
bsm
bsbm
ffB
fffB
ffffB
+∆=
+−=
−−+=
11/14/2012 25
)(2 bffB +∆=
)(2 bffB +∆=
BĂNG THÔNG T I THI U C A TÍNBĂNG THÔNG T I THI U C A TÍN Hi UHi U FSK:FSK:
26. BFSKBFSK -- MODULATION INDEXMODULATION INDEX
af
f∆
=β
THE REPETITION RATETHE REPETITION RATE bf
f∆
=
2
β22
1 b
b
a
f
t
f ==
b
sm
b f
ff
f
f −
=
∆
=∴
2
β
ff −
SEPERATION INSEPERATION IN
MARK AND SPACEMARK AND SPACE
FREQUENCIESFREQUENCIES
11/14/2012 26
bsm
b
sm
fff
f
ff
=−⇒=
−
=• 1;1β
2
5.;5.
b
sm
b
sm f
ff
f
ff
=−⇒=
−
=• β
bsm
b
sm
fff
f
ff
22;2 =−⇒=
−
=• β
27. FREQUENCY SHIFT KEYING (FSK, BFSK)FREQUENCY SHIFT KEYING (FSK, BFSK)
bsm fff >−
•• WIDEWIDE--BAND FSK:BAND FSK:
•• H SH S ði Uði U CH :CH :
b
sm
b
sm
a f
ff
f
ff
f
f
h
−
=
−
=
∆
=
2
2
11/14/2012 27
bsm fff >−
•• NARROWNARROW--BAND FSK:BAND FSK:
bsm fff <−
28. FSK EXAMPLEFSK EXAMPLE
CHO TÍNCHO TÍN Hi UHi U FSK V I MARK FREQUENCY LÀ 51 kHz, SPACEFSK V I MARK FREQUENCY LÀ 51 kHz, SPACE
FREQUENCY LÀ 49 kHz, VÀ T C ð BIT NGÕ VÀO LÀ 2 Kbps:FREQUENCY LÀ 49 kHz, VÀ T C ð BIT NGÕ VÀO LÀ 2 Kbps:
••ð L CH T N ð NHð L CH T N ð NH
2
sm
f
ff −
=∆ kHz
kHzkHz s
f 1
2
4951
=
−
=∆
•• BĂNG THÔNG T I THI UBĂNG THÔNG T I THI U
11/14/2012 28
•• BĂNG THÔNG T I THI UBĂNG THÔNG T I THI U
)(2 bffB +∆= kHzkHzkHzB 6)21(2 =+=
•• T C ð BAUDT C ð BAUD
WITH BFSK, THE BIT RATE EQUALS THE BAUD RATEWITH BFSK, THE BIT RATE EQUALS THE BAUD RATE
BAUD RATE = 2 kbpsBAUD RATE = 2 kbps
29. NONCOHERENT FSK RECEIVERNONCOHERENT FSK RECEIVER
KHÔNG CÓ T N S ðƯ C THÊM VÀO TRONG QUÁ TRÌNH GI I ðI U CHKHÔNG CÓ T N S ðƯ C THÊM VÀO TRONG QUÁ TRÌNH GI I ðI U CH
ð ð NG B C V PHA, T N S HAY C HAI V I TÍN HI U VÀO FSKð ð NG B C V PHA, T N S HAY C HAI V I TÍN HI U VÀO FSK
11/14/2012 29
00
OROR
11
30. COHERENT FSK RECEIVERCOHERENT FSK RECEIVER
TÍNTÍN Hi UHi U VÀO FSK ðƯ C NHÂN V I SÓNG MANG ðƯ C KHÔI PH CVÀO FSK ðƯ C NHÂN V I SÓNG MANG ðƯ C KHÔI PH C
CHÍNH XÁC V T N S VÀ PHA NHƯ C A B TRUY NCHÍNH XÁC V T N S VÀ PHA NHƯ C A B TRUY N
11/14/2012 30
00
OROR
11
Hi MHi M KHI S D NG K THU T: LÀ KHÔNG TH C T ð TÁI T O M T CÁI LOCALKHI S D NG K THU T: LÀ KHÔNG TH C T ð TÁI T O M T CÁI LOCAL
REFERENCE CÓ TH LIÊN K T C MARK AND SPACE FREQUENCIESREFERENCE CÓ TH LIÊN K T C MARK AND SPACE FREQUENCIES
31. PLLPLL--BASED FSK RECEIVERBASED FSK RECEIVER
FREQUENCY VARIESFREQUENCY VARIES
BETWEEN MARK AND SPACEBETWEEN MARK AND SPACE
FREQUENCIESFREQUENCIES
FOLLOWS THE FREQUENCYFOLLOWS THE FREQUENCY
SHIFTSHIFT
11/14/2012 31
00
OROR
11
2
sm
osc
ff
f
−
=
32. CONTINUOUSCONTINUOUS --PHASE (CPPHASE (CP--FSK)FSK)
•• CPCP--FSK IS BFSK V I MARK AND SPACEFSK IS BFSK V I MARK AND SPACE
FREQUENCIES ðƯ C ð NG B T C ð BIT NHFREQUENCIES ðƯ C ð NG B T C ð BIT NH
PHÂN NGÕ VÀOPHÂN NGÕ VÀO
•• sm ff , ðƯ C CH N SAO CHO CHÚNGðƯ C CH N SAO CHO CHÚNG
PHÂN BI T V I T N S TRUNG TÂM B NGPHÂN BI T V I T N S TRUNG TÂM B NG
S L L N C A ½ T C ð BITS L L N C A ½ T C ð BIT
11/14/2012 32
=
2
b
mm
f
nf
•• ðI U NÀY B O ð M S CHUY N PHA SUÔN SðI U NÀY B O ð M S CHUY N PHA SUÔN S
TÍN HI U NGÕ RA KHI THAY ð I GI A 2TÍN HI U NGÕ RA KHI THAY ð I GI A 2
T N ST N S
=
2
b
ss
f
nf
≠ sm
sm
nn
oddnoddn ;
S L L N C A ½ T C ð BITS L L N C A ½ T C ð BIT
35. CONTINUOUSCONTINUOUS--PHASE FSK WAVEFORMPHASE FSK WAVEFORM
IN THE CPIN THE CP--FSK EXAMPLE:FSK EXAMPLE:
1500;3500
4
3;7;1000
==
=−∴
===
m
sm
smb
HzfsHzf
and
nn
nnHzf
11/14/2012 35
)2(22000
1500;3500
===−∴
==
βbsm
m
fHzff
HzfsHzf
Hz
ff
f
sm
1000
2
2000
2
==
−
=∆
Hzfffff smosc 2500=∆+=∆−=
37. MINIMUM CPMINIMUM CP--FSKFSK -- MSKMSK
PHÂN BI T T I THI U C A MARK AND SPACEPHÂN BI T T I THI U C A MARK AND SPACE
FREQUENCIES X Y RA KHIFREQUENCIES X Y RA KHI
b
ss
b
sm
f
nf
f
nf =+=
2
;
2
)2(
2+= sm nn
11/14/2012 37
1=⇒=− βbsm fff
H S ðI U CH LÀ 1 VÀ CHÚNG TA G I MSK NÀYH S ðI U CH LÀ 1 VÀ CHÚNG TA G I MSK NÀY
b
b
sm f
f
ff ==−∴
2
2
22
41. PHASE SHIFT KEYING (PSK, BPSK)PHASE SHIFT KEYING (PSK, BPSK)
•• CŨNG ðƯ C G I LÀ PHASE REVERSAL KEYING (PRK)CŨNG ðƯ C G I LÀ PHASE REVERSAL KEYING (PRK)
VÀ BIPHASE MODULATIONVÀ BIPHASE MODULATION
•• BPSK THÌ TƯƠNG T NHƯ PM (BIÊN ð VÀ T N SBPSK THÌ TƯƠNG T NHƯ PM (BIÊN ð VÀ T N S
KHÔNG ð I) NGO I TR TÍNKHÔNG ð I) NGO I TR TÍN Hi UHi U ði Uði U CH LÀ NHCH LÀ NH
PHÂN (PHÂNPHÂN (PHÂN Bi TBi T Gi AGi A 2 M C RIÊNG2 M C RIÊNG Bi TBi T))
11/14/2012 41
•• V I BPSK 2 PHA NGÕ RA CÓ TH T O B I 1 T N SV I BPSK 2 PHA NGÕ RA CÓ TH T O B I 1 T N S
SÓNG MANG. PHA C A TÍNSÓNG MANG. PHA C A TÍN Hi UHi U SÓNG MANG NGÕSÓNG MANG NGÕ
RA L CH NHAU 180RA L CH NHAU 18000 ðð Bi UBi U Di NDi N M C LOGIC 0 VÀ 1M C LOGIC 0 VÀ 1
•• BPSK LÀ 1 D NG C A DSBBPSK LÀ 1 D NG C A DSB--SCSC
42. BPSK TRANSMITTERBPSK TRANSMITTER
PHASE REVERSING SWITCHPHASE REVERSING SWITCH
(PRODUCT MODULATOR)(PRODUCT MODULATOR)
CARRIER IS EITHERCARRIER IS EITHER
IN PHASE (‘1’ INPUT)IN PHASE (‘1’ INPUT)
LOGICAL 0,LOGICAL 0,
UNIPOLARUNIPOLAR BIPOLARBIPOLAR
tbtb
11/14/2012 42
IN PHASE (‘1’ INPUT)IN PHASE (‘1’ INPUT)
OR 180 degrees OUT OFOR 180 degrees OUT OF
PHASE (‘0’ INPUT)PHASE (‘0’ INPUT)
CARRIER FREQUENCYCARRIER FREQUENCY
LOGICAL 0,LOGICAL 0,
LOGICAL 1LOGICAL 1
INPUTINPUT
OUTPUT RATE OFOUTPUT RATE OF
CHANGE (BAUD) =CHANGE (BAUD) =
INPUT RATE OF CHANGEINPUT RATE OF CHANGE
((bpsbps).). SYMBOL = BITSYMBOL = BIT
43. BPSK BALANCED RING MODULATORBPSK BALANCED RING MODULATOR
11/14/2012 43
DIGITAL VOLTAGE INPUT >>> PEAK CARRIER VOLTAGEDIGITAL VOLTAGE INPUT >>> PEAK CARRIER VOLTAGE
IN ORDER TO CONTROL D1IN ORDER TO CONTROL D1--D4 DIODE STATESD4 DIODE STATES
44. BPSK BALANCED RING MODULATORBPSK BALANCED RING MODULATOR
LOGICAL 1 INPUTLOGICAL 1 INPUT
11/14/2012 44
OUTPUTOUTPUT
SIGNAL IS INSIGNAL IS IN
PHASEPHASE
45. BPSK BALANCED RING MODULATORBPSK BALANCED RING MODULATOR
LOGICAL 0 INPUTLOGICAL 0 INPUT
11/14/2012 45
OUTPUTOUTPUT
SIGNAL ISSIGNAL IS
180 degrees OUT180 degrees OUT
OF PHASEOF PHASE
46. BPSK BALANCED RING MODULATORBPSK BALANCED RING MODULATOR
TRUTH TABLETRUTH TABLE
PHASOR DIAGRAMPHASOR DIAGRAM
11/14/2012 46
PHASOR DIAGRAMPHASOR DIAGRAM
CONSTELLATION DIAGRAMCONSTELLATION DIAGRAM
(SIGNAL STATE(SIGNAL STATE--SPACE DIAGRAM)SPACE DIAGRAM)
ONLY THE RELATIVE PEAKSONLY THE RELATIVE PEAKS
OF THE PHASORS ARE SHOWNOF THE PHASORS ARE SHOWN
47. BPSK GENERATIONBPSK GENERATION
[ ])2sin()()( tftvtv cmpsk π=
≡cf REFERENCE CARRIER FREQUENCYREFERENCE CARRIER FREQUENCY
=+ 1log1 icalVNORMALIZEDNORMALIZED
≡)(tvm INPUT BINARY SIGNALINPUT BINARY SIGNAL
11/14/2012 47
=−
=+
=
0log1
1log1
)(
icalV
icalV
tvm
NORMALIZEDNORMALIZED
INPUT SIGNALINPUT SIGNAL
(UNIPOLAR TO(UNIPOLAR TO
BIPOLAR SIGNAL)BIPOLAR SIGNAL)
−
+
=
inputicalt
inputicalt
tv
c
c
psk
0log;sin
1log;sin
)(
ω
ω IN PHASEIN PHASE
OUT OFOUT OF
PHASEPHASE
49. BANDWITH CONSIDERATION OF BPSKBANDWITH CONSIDERATION OF BPSK
[ ][ ])2sin()2sin()( tftftv acpsk ππ=
≡cf REFERENCE CARRIER FREQUENCYREFERENCE CARRIER FREQUENCY
REPETITION RATE (FUNDAMENTALREPETITION RATE (FUNDAMENTAL
FREQUENCY OF BINARY INPUT)FREQUENCY OF BINARY INPUT)
IT IS 1/2 THE BIT RATEIT IS 1/2 THE BIT RATE
≡==
22
1 b
b
a
f
t
f
11/14/2012 49
IT IS 1/2 THE BIT RATEIT IS 1/2 THE BIT RATEb
)cos(
2
1
)cos(
2
1
))(sin(sin YXYXYX +−−=
[ ] [ ]tfftfftv acacpsk )(2cos
2
1
)(2cos
2
1
)( +−−= ππ
LOWER SIDE FREQUENCYLOWER SIDE FREQUENCY UPPER SIDE FREQUENCYUPPER SIDE FREQUENCY
50. ff +ff − f
B
BANDWITH CONSIDERATION OF BPSKBANDWITH CONSIDERATION OF BPSK
LSBLSB USBUSB
2
b
a
f
f =
2
b
a
f
f =
11/14/2012 50
ac ff +ac ff −
cf
b
b
a f
f
fB ===
2
22
LSFLSF USFUSF
DSBDSB--SC MODULATIONSC MODULATION
51. EXAMPLEEXAMPLE
FOR A BPSK MODULATOR WITH A CARRIERFOR A BPSK MODULATOR WITH A CARRIER
FREQUENCY OF 70 MHz AND AN INPUT BIT RATE OFFREQUENCY OF 70 MHz AND AN INPUT BIT RATE OF
10 Mbps, DETERMINE a) THE LSF b) USF c) B d) BAUD RATE10 Mbps, DETERMINE a) THE LSF b) USF c) B d) BAUD RATE
MHzfc 70=
ab
b
a ff
f
f 2;
2
==
MHzfb 10=
11/14/2012 51
aba
2
MHz
MHz
fa 5
2
10
==
MHzffLSF ac 65570 =−=−=
MHzffUSF ac 75570 =+=+=
MHzfB b 10==
53. BPSK RECEIVERBPSK RECEIVER
++
INPUT BPSKINPUT BPSK
SIGNALSIGNAL
PRODUCTPRODUCT
MODULATORMODULATOR
22
11/14/2012 53
FREQUENCY AND PHASEFREQUENCY AND PHASE
SYNCHRONIZED TO ORIGINALSYNCHRONIZED TO ORIGINAL
TRANSMIT CARRIERTRANSMIT CARRIER
SYNCHRONIZED TOSYNCHRONIZED TO
BIT RATEBIT RATE
54. BPSK DETECTIONBPSK DETECTION
ttttv ccc ωωω 2
mod sin2))(sin(sin2)( ==
ttv cm ωsin)( +=
XX 2cos
2
1
2
1
sin2
−=
LOGICAL 1:LOGICAL 1:
))(sin(2)(mod ttvtv cm ω=
−= ttv cω2cos
11
2)(mod
11/14/2012 54
XX 2cos
22
sin −=
−= ttv cω2cos
22
2)(mod
ttv cω2cos1)(mod −=
BLOCKED BY LPFBLOCKED BY LPF
V1)( =tvout LOGICAL 1:LOGICAL 1:
55. BPSK DETECTIONBPSK DETECTION
ttttv ccc ωωω 2
mod sin2))(sinsin(2)( −=−=
ttv cm ωsin)( −=
XX 2cos
2
1
2
1
sin2
−=
LOGICAL 0:LOGICAL 0:
))(sin(2)(mod ttvtv cm ω=
−−= ttv cω2cos
11
2)(mod
11/14/2012 55
XX 2cos
22
sin −=
−−= ttv cω2cos
22
2)(mod
ttv cω2cos1)(mod +−=
BLOCKED BY LPFBLOCKED BY LPF
V1)( −=tvout LOGICAL 0LOGICAL 0
56. MM--ARYARY ENCODINGENCODING
•• M LÀ M T S TH P PHÂNM LÀ M T S TH P PHÂN Bi UBi U Di NDi N S LƯ NGS LƯ NG
K T H P CÓ TH CHO 1 S BIT NH PHÂN CHOK T H P CÓ TH CHO 1 S BIT NH PHÂN CHO
TRƯ C (N)TRƯ C (N)
•• ði Uði U CH S BFSK VÀ BPSK MÃ HÓA 1 BIT ðƠNCH S BFSK VÀ BPSK MÃ HÓA 1 BIT ðƠN
VÀ CÓ TH CÓ 2 CÁCH K T H P NGÕVÀ CÓ TH CÓ 2 CÁCH K T H P NGÕ
(N = 1, 0 AND 1 INPUTS)(N = 1, 0 AND 1 INPUTS)
11/14/2012 56
(N = 1, 0 AND 1 INPUTS)(N = 1, 0 AND 1 INPUTS)
•• EXAMPLE: H TH NG PSK V I 4 PHA NGÕ RA LÀEXAMPLE: H TH NG PSK V I 4 PHA NGÕ RA LÀ
H TH NG MH TH NG M--ARYARY V I M = 4V I M = 4
•• BINARY LÀ MBINARY LÀ M--ARYARY V I M = 2V I M = 2
•• BPSK: M = 2, N = 1BPSK: M = 2, N = 1
57. MM--ARYARY ENCODING: M & N RELATIONSHIPENCODING: M & N RELATIONSHIP
MN
M N
2log
2
=
=
V I BFSK/BPSK, 1 BIT ðƯ C MÃ HÓA:V I BFSK/BPSK, 1 BIT ðƯ C MÃ HÓA:
T NG QUÁTT NG QUÁT
N = 1N = 1
11/14/2012 57
N = 1N = 1
M = 2M = 2
EXAMPLE:EXAMPLE:
N U NGÕ VÀO BAO G M 2 BIT, ðƯ C MÃ HÓA V IN U NGÕ VÀO BAO G M 2 BIT, ðƯ C MÃ HÓA V I
NHAU VÀ SAU ðÓ ðƯ CNHAU VÀ SAU ðÓ ðƯ C ði Uði U CH CÙNG 1 SÓNGCH CÙNG 1 SÓNG
MANG, THÌ: N = 2, M = 4MANG, THÌ: N = 2, M = 4
58. MINIMUM MMINIMUM M--ARYARY REQUIRED BANDWITHREQUIRED BANDWITH
N
f
M
f
B bb
==
2log
11/14/2012 58
N LÀ S LƯ NG BIT NRZ MÃ HÓAN LÀ S LƯ NG BIT NRZ MÃ HÓA
59. QUATERNARY PHASE SHIFT KEYING (QPSK)QUATERNARY PHASE SHIFT KEYING (QPSK)
•• CŨNG ðƯ C G I LÀ QUADRATURE PSKCŨNG ðƯ C G I LÀ QUADRATURE PSK
•• M T D NG KHÁC C A PMM T D NG KHÁC C A PM
•• QPSK LÀ 1 K THU T MÃ HÓA MQPSK LÀ 1 K THU T MÃ HÓA M--ARYARY V I M = 4V I M = 4
11/14/2012 59
•• V I QPSK, 4 PHA NGÕ RA ðƯ C TH CV I QPSK, 4 PHA NGÕ RA ðƯ C TH C Hi NHi N V IV I
1 SÓNG MANG1 SÓNG MANG
•• N = 2 (2 BITS) VÌ:N = 2 (2 BITS) VÌ:
4log2log 22 =⇒= MN
60. QUATERNARY PHASE SHIFT KEYING (QPSK)QUATERNARY PHASE SHIFT KEYING (QPSK)
•• DD Li ULi U NH PHÂN NGÕ VÀO ðƯ C K T H PNH PHÂN NGÕ VÀO ðƯ C K T H P
THÀNH NHÓM 2 BIT G I LÀTHÀNH NHÓM 2 BIT G I LÀ DIBITSDIBITS
•• DIBITDIBIT CODE: 00 = PHASE 1, 01 = PHASE 2,CODE: 00 = PHASE 1, 01 = PHASE 2,
10 = PHASE 3, 11 = PHASE 410 = PHASE 3, 11 = PHASE 4
11/14/2012 60
•• 1 SYMBOL = 1 PHASE = 2 BITS1 SYMBOL = 1 PHASE = 2 BITS
BAUD RATE = 1/2BAUD RATE = 1/2 BIT RATEBIT RATE
(SYMBOLS PER SEC)(SYMBOLS PER SEC) ((BITS PER SECBITS PER SEC))
70. QPSK GENERATION: OUTPUT PHASESQPSK GENERATION: OUTPUT PHASES
11/14/2012 70
OUTPUT PHASE VERSUS TIME FOR QPSK MODULATOROUTPUT PHASE VERSUS TIME FOR QPSK MODULATOR
71. QPSK GENERATION: OUTPUT PHASESQPSK GENERATION: OUTPUT PHASES
V I QPSK, M T TRONG 4 KH NĂNG NGÕ RAV I QPSK, M T TRONG 4 KH NĂNG NGÕ RA
PHASORS CÓ CÙNG BIÊN ð .PHASORS CÓ CÙNG BIÊN ð .
11/14/2012 71
VÌ TH , THÔNG TIN NH PHÂN PH I ðƯ C MÃ HÓAVÌ TH , THÔNG TIN NH PHÂN PH I ðƯ C MÃ HÓA
HOÀN TOÀN TRONG PHA C A TÍNHOÀN TOÀN TRONG PHA C A TÍN Hi UHi U NGÕ RANGÕ RA
72. QPSK GENERATIONQPSK GENERATION
tbtb tbtb
1 f
BIT RATE BEFORE SPLITTER =BIT RATE BEFORE SPLITTER = b
b
f
t
=
1
II
QQ
tbtb tbtb
SERIALSERIAL
PARALLELPARALLEL
I or QI or Q
(SERIAL)(SERIAL)
11/14/2012 72
22
1 b
b
r
f
t
f ==
bt
REPETITION RATE BEFORE SPLITTERREPETITION RATE BEFORE SPLITTER
BIT RATE AFTER SPLITTER =BIT RATE AFTER SPLITTER =
22
1 b
b
f
t
=
REPETITION RATE AFTER SPLITTERREPETITION RATE AFTER SPLITTER
44
1 b
b
r
f
t
f ==
(SERIAL)(SERIAL)
(SERIAL)(SERIAL)
(PARALLEL)(PARALLEL)
(PARALLEL)(PARALLEL)
73. BANDWITH CONSIDERATION OF QPSKBANDWITH CONSIDERATION OF QPSK
[ ][ ])2sin()2sin()( tftftv rcqpsk ππ=
≡cf REFERENCE CARRIER FREQUENCYREFERENCE CARRIER FREQUENCY
REPETITION RATE (FUNDAMENTALREPETITION RATE (FUNDAMENTAL
FREQUENCY OF I or Q CHANNEL BITS)FREQUENCY OF I or Q CHANNEL BITS)
IT IS 1/4 THE BIT RATEIT IS 1/4 THE BIT RATE4
b
r
f
f =
11/14/2012 73
IT IS 1/4 THE BIT RATEIT IS 1/4 THE BIT RATE
)cos(
2
1
)cos(
2
1
))(sin(sin YXYXYX +−−=
[ ] [ ]tfftfftv rcrcpsk )(2cos
2
1
)(2cos
2
1
)( +−−= ππ
LOWER SIDE FREQUENCYLOWER SIDE FREQUENCY UPPER SIDE FREQUENCYUPPER SIDE FREQUENCY
74. rc ff +rc ff − f
B
BANDWITH CONSIDERATION OF BPSKBANDWITH CONSIDERATION OF BPSK
LSBLSB USBUSB
4
b
r
f
f =
4
b
r
f
f =
11/14/2012 74
rc ff +rc ff − cf
24
22
bb
r
ff
fB ===
LSFLSF USFUSF
DSBDSB--SC MODULATIONSC MODULATION
75. EXAMPLEEXAMPLE
V I BV I B ði Uði U CH QPSK V I T N S SÓNG MANGCH QPSK V I T N S SÓNG MANG
LÀ 70 MHz VÀ T C ð BIT NGÕ VÀO LÀ 10 Mbps,LÀ 70 MHz VÀ T C ð BIT NGÕ VÀO LÀ 10 Mbps,
XÁC ð NH a) THE LSF b) USF c) B d) BAUD RATEXÁC ð NH a) THE LSF b) USF c) B d) BAUD RATE
MHzfc 70=
rb
b
r ff
f
f 4;
4
==
MHzfb 10=
11/14/2012 75
4
MHz
MHz
fr 5.2
4
10
==
MHzffLSF rc 5.675.270 =−=−=
MHzffUSF rc 5.725.270 =+=+=
MHz
f
B
b
5
2
==
81. EIGHT PHASE SHIFT KEYING (8EIGHT PHASE SHIFT KEYING (8--PSK)PSK)
•• D NG MÃ MD NG MÃ M--ARYARY V I M = 8, N = 3V I M = 8, N = 3
•• 8 PHA NGÕ RA CÓ TH CÓ8 PHA NGÕ RA CÓ TH CÓ
•• DD Li ULi U NGÕ VÀO NH PHÂN K T H P THÀNHNGÕ VÀO NH PHÂN K T H P THÀNH
NHÓM 3 BIT (N = 3) G I LÀNHÓM 3 BIT (N = 3) G I LÀ TRIBITSTRIBITS
•• TRIBITTRIBIT CODE: 000 = PHASE 1, 001 = PHASE 2, 010 = PHASE 3CODE: 000 = PHASE 1, 001 = PHASE 2, 010 = PHASE 3
011 = PHASE 4, 100 = PHASE 5, 101 = PHASE 6011 = PHASE 4, 100 = PHASE 5, 101 = PHASE 6
110 = PHASE 7, 111 = PHASE 8110 = PHASE 7, 111 = PHASE 8
11/14/2012 81
110 = PHASE 7, 111 = PHASE 8110 = PHASE 7, 111 = PHASE 8
•• 1 SYMBOL = 1 PHASE = 3 BITS1 SYMBOL = 1 PHASE = 3 BITS
BAUD RATE = 1/3BAUD RATE = 1/3 BIT RATEBIT RATE
(SYMBOLS PER SEC)(SYMBOLS PER SEC) ((BITS PER SECBITS PER SEC))
83. 88--PSK MODULATORPSK MODULATOR
I CHANNELI CHANNEL
TRUTH TABLETRUTH TABLE
Q CHANNELQ CHANNEL
TRUTH TABLETRUTH TABLE
PAM SIGNALPAM SIGNAL
(4 LEVELS)(4 LEVELS)
11/14/2012 83
•• I, Q DETERMINE POLARITY; 0 =I, Q DETERMINE POLARITY; 0 = -- , 1 = +, 1 = +
•• DETERMINE THE LEVEL; 1 = 1.307v, 0 = 0.541vDETERMINE THE LEVEL; 1 = 1.307v, 0 = 0.541v
•• 2 LEVELS + 2 POLARITIES GIVE 4 CONDITIONS2 LEVELS + 2 POLARITIES GIVE 4 CONDITIONS
CC ,
84. 88--PSK GENERATION: TRIBIT = 000PSK GENERATION: TRIBIT = 000
000000
00
00
-- 0.541v0.541v
)2sin(541.0 tfcπ−
11/14/2012 84
00
11 -- 1.307v1.307v
NOTE: BECAUSE NOT THE SAME, INOTE: BECAUSE NOT THE SAME, I--CHANNELCHANNEL
PAM WILL NEVER EQUAL QPAM WILL NEVER EQUAL Q--CHANNEL PAMCHANNEL PAM
CC ,
)2cos(307.1 tfcπ−
85. 88--PSK GENERATION: OUTPUT PHASESPSK GENERATION: OUTPUT PHASES
TRIBIT CODE: 000TRIBIT CODE: 000
)5.112sin(41.1)cos(307.1)sin(541.0 o
−=−− ttt ccc ωωω
PROOF:PROOF: YXYXYX sincoscossin)sin( −=−
)5.1122sin(41.1 tfcπ =− o
11/14/2012 85
)2cos(307.1)2sin(541.0
)2cos()924(.41.1)2sin()383.(41.1
)5.112sin()2cos(41.1)5.112cos()2sin(41.1
)5.1122sin(41.1
tftf
tftf
tftf
tf
cc
cc
cc
c
ππ
ππ
ππ
π
−−
=−−
=−
=−
0 0 0 ==>0 0 0 ==> --112.5 degrees112.5 degrees
86. 88--PSK GENERATION: OUTPUT PHASESPSK GENERATION: OUTPUT PHASES
TRIBIT CODE BETWEENTRIBIT CODE BETWEEN
ADJACENT PHASESADJACENT PHASES
FOLLOWS THEFOLLOWS THE
GRAYCODEGRAYCODE
(RESULTS IN ONLY(RESULTS IN ONLY
A SINGLE BIT ERRORA SINGLE BIT ERROR
FOR UNDESIRED PHASEFOR UNDESIRED PHASE
SHIFTS)SHIFTS)
11/14/2012 86
87. 88--PSK GENERATION: OUTPUT PHASESPSK GENERATION: OUTPUT PHASES
•• V I QPSK: 4 PHA NGÕ RA (+45, +135,V I QPSK: 4 PHA NGÕ RA (+45, +135, --45,45, --135)135)
PHÂNPHÂN Bi TBi T Gi AGi A CÁC PHASORCÁC PHASOR Li NLi N K LÀK LÀ
360/4 = 90 degrees.360/4 = 90 degrees.
•• V I 8V I 8--PSK: 8 PHA NGÕ RA. PHÂNPSK: 8 PHA NGÕ RA. PHÂN Bi TBi T Gi AGi A CÁCCÁC
11/14/2012 87
•• V I 8V I 8--PSK: 8 PHA NGÕ RA. PHÂNPSK: 8 PHA NGÕ RA. PHÂN Bi TBi T Gi AGi A CÁCCÁC
PHA LÀ 360/8 = 45 degrees. M T TÍNPHA LÀ 360/8 = 45 degrees. M T TÍN Hi UHi U 88--PSK CÓ THPSK CÓ TH
CH U S D CH PHA +/CH U S D CH PHA +/-- 22.5 degrees TRONG QUÁ TRÌNH22.5 degrees TRONG QUÁ TRÌNH
TRUY N VÀ V NTRUY N VÀ V N GiGi TÍNH TOÀN V N.TÍNH TOÀN V N.
88. 88--PSK GENERATION: OUTPUT PHASESPSK GENERATION: OUTPUT PHASES
•• V I 8V I 8--PSK, M I PHASOR CÓ BIÊN ð B NG NHAUPSK, M I PHASOR CÓ BIÊN ð B NG NHAU
(1.41v)(1.41v)
11/14/2012 88
•• THÔNG TIN MÃ TRIBIT CH ðƯ C CH A TRONGTHÔNG TIN MÃ TRIBIT CH ðƯ C CH A TRONG
PHA C A TÍNPHA C A TÍN Hi UHi U
89. 88--PSK GENERATION: OUTPUT PHASESPSK GENERATION: OUTPUT PHASES
11/14/2012 89
OUTPUT PHASE VERSUS TIME FOR 8OUTPUT PHASE VERSUS TIME FOR 8--PSK MODULATORPSK MODULATOR
90. tbtb tbtb
1 f
BIT RATE BEFORE SPLITTER =BIT RATE BEFORE SPLITTER = b
b
f
t
=
1
II
QQ
tbtb tbtb
SERIALSERIAL
PARALLELPARALLEL
I or Q or CI or Q or C
(SERIAL)(SERIAL)
CC
BANDWITH CONSIDERATION OF 8BANDWITH CONSIDERATION OF 8--PSKPSK
11/14/2012 90
22
1 b
b
r
f
t
f ==
bt
REPETITION RATE BEFORE SPLITTERREPETITION RATE BEFORE SPLITTER
BIT RATE AFTER SPLITTER =BIT RATE AFTER SPLITTER =
33
1 b
b
f
t
=
REPETITION RATE AFTER SPLITTERREPETITION RATE AFTER SPLITTER
6)3(2
1 b
b
r
f
t
f ==
(SERIAL)(SERIAL)
(SERIAL)(SERIAL)
(PARALLEL)(PARALLEL)
(PARALLEL)(PARALLEL)
92. 88--PSK GENERATION: BAUD RATEPSK GENERATION: BAUD RATE
•• V I 8V I 8--PSK, CÓ 1 THAY ð I PHA T I NGÕ RA M I 3PSK, CÓ 1 THAY ð I PHA T I NGÕ RA M I 3
BIT VÀO.BIT VÀO.
(A GROUP OF THREE BITS = 1 PHASE = 1 SYMBOL)(A GROUP OF THREE BITS = 1 PHASE = 1 SYMBOL)
11/14/2012 92
VÌ TH , THE BAUD RATE = 1/3 BIT RATE =VÌ TH , THE BAUD RATE = 1/3 BIT RATE =
3
bf
93. BANDWITH CONSIDERATION OF 8BANDWITH CONSIDERATION OF 8--PSKPSK
[ ][ ])2sin()2sin()(8 tfXtftv rcpsk ππ=
≡cf REFERENCE CARRIER FREQUENCYREFERENCE CARRIER FREQUENCY
REPETITION RATE (FUNDAMENTALREPETITION RATE (FUNDAMENTAL
FREQUENCY OF I or Q or C CHANNEL BITS)FREQUENCY OF I or Q or C CHANNEL BITS)
IT IS 1/6 THE BIT RATEIT IS 1/6 THE BIT RATE6
b
r
f
f =
X = +/X = +/-- 1.307 OR +/1.307 OR +/-- 0.5410.541
11/14/2012 93
IT IS 1/6 THE BIT RATEIT IS 1/6 THE BIT RATE6
)cos(
2
1
)cos(
2
1
))(sin(sin YXYXYX +−−=
[ ] [ ]tff
X
tff
X
tv rcrcpsk )(2cos
2
)(2cos
2
)( +−−= ππ
LOWER SIDE FREQUENCYLOWER SIDE FREQUENCY UPPER SIDE FREQUENCYUPPER SIDE FREQUENCY
94. rc ff +rc ff − f
B
BANDWITH CONSIDERATION OF 8BANDWITH CONSIDERATION OF 8--PSKPSK
LSBLSB USBUSB
6
b
r
f
f =
6
b
r
f
f =
11/14/2012 94
rc ff +rc ff − cf
36
22
bb
r
ff
fB ===
LSFLSF USFUSF
DSBDSB--SC MODULATIONSC MODULATION
95. EXAMPLEEXAMPLE
V I BV I B ði Uði U CH CÓ T N S SÓNG MANG LÀ 70 MHzCH CÓ T N S SÓNG MANG LÀ 70 MHz
VÀ T C ð BIT NGÕ VÀO LÀ 10 Mbps,VÀ T C ð BIT NGÕ VÀO LÀ 10 Mbps,
XÁC ð NH a) THE LSF b) USF c) B d) BAUD RATEXÁC ð NH a) THE LSF b) USF c) B d) BAUD RATE
MHzfc 70=
rb
b
r ff
f
f 6;
6
==
MHzfb 10=
11/14/2012 95
6
MHz
MHz
fr 667.1
6
10
==
MHzffLSF rc 333.68667.170 =−=−=
MHzffUSF rc 667.71667.170 =+=+=
MHz
f
B
b
33.3
3
==
99. SIXTEEN PHASE SHIFT KEYING (16SIXTEEN PHASE SHIFT KEYING (16--PSK)PSK)
•• D NG MÃ HÓA MD NG MÃ HÓA M--ARYARY V I M = 16, N = 4V I M = 16, N = 4
•• 16 PHA TÍN16 PHA TÍN Hi UHi U NGÕ RANGÕ RA
•• DD Li ULi U NH PHÂN NGÕ VÀO ðƯ C NHÓM THÀNHNH PHÂN NGÕ VÀO ðƯ C NHÓM THÀNH
NHÓM 4 BIT (N = 4) G I LÀNHÓM 4 BIT (N = 4) G I LÀ QUADBITSQUADBITS
•• QUADBITQUADBIT CODE: 0000 = PHASE 1 ……….. 1111 = PHASE 16,CODE: 0000 = PHASE 1 ……….. 1111 = PHASE 16,
•• 1 SYMBOL = 1 PHASE = 4 BITS1 SYMBOL = 1 PHASE = 4 BITS
11/14/2012 99
•• 1 SYMBOL = 1 PHASE = 4 BITS1 SYMBOL = 1 PHASE = 4 BITS
BAUD RATE = 1/4BAUD RATE = 1/4 BIT RATEBIT RATE
(SYMBOLS PER SEC)(SYMBOLS PER SEC) ((BITS PER SECBITS PER SEC))
•• V I 16V I 16--PSK, CÁC GÓC PHA ðƯ C PHÂNPSK, CÁC GÓC PHA ðƯ C PHÂN Bi TBi T LÀLÀ
360/16 = 22.5 degrees. ð CÓ TH360/16 = 22.5 degrees. ð CÓ TH GiGi TOÀN V N,TOÀN V N,
D CH PHA max = +/D CH PHA max = +/-- 11.25 degrees11.25 degrees