This document discusses communication technologies including television. It describes how television works by transforming light and sound into electrical signals that are broadcast through radio waves or cables. The document outlines the television broadcasting process where images and sound are compressed into a digital format and transmitted. It also discusses technologies related to television like digital terrestrial television, high frame rate recording, and RGB pixels.

1. UNIT 1
COMMUNICATION
TECHNOLOGIES
TECHNOLOGIES, PROGRAMMING AND ROBOTICS
3 ESO

2. INDEX
• MOBILE PHONES
• RADIO
• SATELLITES AND POSITIONING SYSTEMS
• TELEVISION
• THE INTERNET
• NEGATIVE EFFECTS OF COMMUNICATION TECHNOLOGIES

3. 4. TELEVISION

4. · Television is an electronic system that transmits
fixed or moving images together with sound over a
wire or through space.
· A television system is able to transform light and
sound into electrical waves and reconverts them
into visible light rays and audible sound.
· The encoding process to transform light and
sound into electromagnetic waves that can be sent
to a receiver is called broadcasting.
· From its origins (first broadcasting in 1929 by the
BBC), television has been a Terrestrial system.
• TELEVISION

5. · Analogue TV used to have interference problems:
the signal degraded with distance and obstacles.
Every channel consumed a big bandwidth.
· Digital Terrestrial Television (developed in the
late 2010s), compresses the information into a
digital format, so more information can travel on
the same frequency.
· Digital television offers better image and sound
quality.
• TDT (TERRESTRIAL DIGITAL TELEVISION)

6. 1. A camera captures images at normally 60 frames per second. Then, the camera
rasterizes the scene (converts the images in rows of pixels). Depending on the
amount of pixels, the pictures can have different formats:
a) Standard definition (SD)  704 x 480 pixels
b) High definition (HD)  1200 to 1920 x 720 to 1.080 pixels
2. A microphone transforms sound waves into electrical impulses.
3. Both signals are compressed into a MPEG-2 file.
4. That compressed information is transmitted through radio waves (images in AM,
sound in FM) and along cables.
5. The broadcaster can choose to transmit only one program in their channel or
multiple programs at the same time because they can broadcast in different formats.
This is called multicasting.
• TELEVISION BROADCASTING PROCESS

7. High Frame Rate (HFR) recording consists
of recording images at 100 frames per
second instead of 60. This Will only be
noticed if our TV set is able to process that
amount of information.
• HIGH FRAME RATE
RGB stands for Red, Green and
Blue, which are the colors of the
subpixels that form every pixel
on a TV screen.
Some TV brands are adding a
4th white subpíxel to improve
brightness
• RGB

8. Rooftop
antenna
Rooftop
antenna
Rooftop
antenna
Rooftop
antenna
Coaxial
cable

9. · There are three ways to receive digital television at home: antenna, cable and
satellite.
· Digital TV sets are able to decompress the digital signals and convert them into
sound and flashes of light.
· Analogue old TV displays can receive data through the DTS thanks to a set-top
box that converts the digital signal into analogue, so the TV set is able to
reproduce it.
• TELEVISION RECEPTION
Rooftop
antenna