Satellite Communication

Slides:



Advertisements
Similar presentations
Introduction A satellite is an object that orbits or revolves around another object. For example, the Moon is a satellite of Earth, and Earth is a satellite.
Advertisements

Komunikasi Satelite Risanuri Hidayat. Pendahuluan World demand for communication facilities carrying many different types of real-time and non-real-time.
ECE 4321 Computer Networks Chapter 4 Transmission Media: Wireless.
Physics 101: Lecture 11, Pg 1 Physics 101: Lecture 11 Centripetal Force l Brief Review of Chapters 1-4 l Textbook Chapter 5 è Uniform circular motion :
Lecture 11: Satellite Communcation Anders Västberg Slides are a selection from the slides from chapter 9 from:
SATELLITE COMMUNICATIONS
GROUP MEMBERS Jalil Ahmed Sadia Imtiaz Zaigham Abbas Faisal Jamil swedishcr.weebly.com 3.
Satellite Television A very brief history of satellites Sputnik 1, the first artificial satellite launched by the Russians on October 4, It contained.
Chapter-5: Circular Motion, the Planets, and Gravity Circular Motion: Centripetal acceleration Centripetal force Newton’s law of universal gravitation.
Climate and Global Change Notes 6-1 Satellite Fundamentals Types of Orbit Lower Earth Orbits (LEO) Polar Orbits Medium Earth Orbits (MEO) Highly Elliptical.
COMMUNICATION GADGETS
Global Satellite Services GEO, MEO and LEO Satellites, IntelSat, and Global Positioning Systems.
CSCI 465 Data Communications and Networks Lecture 6 Martin van Bommel CSCI 465 Data Communications and Networks 1.
Satellite Communications
COMT 3911 Satellite Basics COMT 391 Wireless. COMT 3912 Satellite Components Satellite Subsystems –Telemetry, Tracking, and Control –Electrical Power.
10. Satellite Communication & Radar Sensors
Satellites.
SATELLITE COMMUNICATION By:-Bhagyalakshmi.Yagnik Roll.no:-13b120.
Satellite Communications
What exactly is a satellite? The word satellite originated from the Latin word “Satellite”- meaning an attendant, one who is constantly hovering around.
SATELLITE ORBITS The monitoring capabilities of the sensor are, to a large extent, governed by the parameters of the satellite orbit. Different types of.
COMPUTER NETWORKING 2 LECTURE 6: satellites technology.
Satellite Systems Presented By Sorath Asnani Mehran University of Engineering & Technology, Jamshoro.
Senior Science Information Systems
Bitwali.com 1 WIRELESS COMMUNICATION LEC bitwali.com 2 TYPES OF SATELLITES Satellite Orbits  GEO  LEO  MEO  Molniya Orbit Frequency Bands.
 CONTENTS :  What’s mean by satellite ?  History of Satellites :  Layer Of Atmosphere :  Generalized communication system :  What are the components.
William Stallings Data and Computer Communications
Space and Gravity By:Nikitha.
Lecture 7: Satellite Networks By: Adal ALashban.
8.3 Universal Gravitation and Orbital Motion
Satellite Communications
Prediction of fading and link budget in land-satellite (LEO) communication Tal Nir & Ziv Gitelman Department of Communication Systems Engineering , Ben-Gurion.
PPT BY:Amy Cha,Laura Collins,Brad Robertson

SENIOR SCIENCE INFORMATION SYSTEMS
Or Stop this Crazy Thing, I have to Go to the Bathroom
SATELLITE Communication.
Satellite Communications
Mobile Computing Chapter 3 :
Presentation On “Overview of Satellite Communication System”
Satellite Communications
Satellites and “Weightlessness”
Kepler’s Laws of Orbital Motion
Satellite communication
Chapter 12 Gravity.
Starter………. Write a new lesson title: ‘Solar System and Satellites’.
Lecture Outline Chapter 12 Physics, 4th Edition James S. Walker
Gravitation.
Satellite Communication
Orbits Pg
Satellites orbits Lec /16/2018 Dr. Hassan Yousif.
Physical Transmission
Satellite Communications
Chapter-5: Circular Motion, the Planets, and Gravity
To Get a Broad View of Earth
Newton’s Universal Law of Gravitation
Classroom Rocket Scientist
Part 1 Gravity: A Force of Attraction
Satellite Communication
INTRODUCTION TO SATELLITE
William Stallings Data and Computer Communications
Chapter 16 Section 9 What are satellites and space probes?
University of Houston Datacom II Lecture 1C Review 2
Universal Gravitation
Anything that can carry information from a source to a destination.
William Stallings Data and Computer Communications
SATELLITE NETWORKS SATELLITE NETWORKS A satellite network is a combination of nodes, some of which are satellites, that provides communication from one.
Cellular Systems.
Presentation transcript:

Satellite Communication Presentation By

Overview Today’s world become a vast network for global communication. With the help of advanced earth stations & new connectivity services makes the critical transmissions to reach their intended targets efficiently and instantly. A big role is played by Satellite Communication for this advancement. The idea of satellite Communication was first introduced by a British Science Fiction writer Authur C. Clarke in 1945. He has already pointed out that a satellite in a circular equatorial orbit with a radius of about 42,242 km wound have an angular velocity that matched the Earth.

Satellite Satellite is an object that orbits another large object like planet. A communication satellite is a station in space that is used for telecommunication, radio and television signals . A satellite is an object in space that orbits or circles around a bigger object. There are two kinds of satellites: natural (such as the moon orbiting the Earth) or artificial (such as the International Space Station orbiting the Earth).There are dozens upon dozens of natural satellites in the solar system, with almost every planet having at least one moon. Saturn, for example, has at least 53 natural satellites To understand why satellites move this way, we must revisit our friend Newton. Newton proposed that a force -- gravity -- exists between any two objects in the universe. If it weren't for this force, a satellite in motion near a planet would continue in motion at the same speed and in the same direction -- a straight line. This straight-line inertial path of a satellite, however, is balanced by a strong gravitational attraction directed toward the center of the planet.

History Early 1950’s and 1960’s,satellite communication by metalized weather balloons. Moon as an artificial satellite. In 1954, the US Naval Research Laboratory successfully transmitted the first voice message. Disadvantage using moon as a satellite….Communications via the Moon is limited by simultaneous visibility of the Moon by both the transmit and the receive stations  The first satellite with radio transmitter was in 1957. In October 1957, the first artificial satellite Sputnik -I was launched. 1963 Clark’s idea became a reality when the first geosynchronous satellite SYNCOM was successfully launched by NASA. India launched its first satellite Aryabhatta on 19 April 1975.

What is Satellite Communication? In satellite communication, signal transferring between the sender and receiver is done with the help of satellite. In this process, the signal which is basically a beam of modulated microwaves is sent towards the satellite. Then the satellite amplifies the signal and sent it back to the receiver’s antenna present on the earth’s surface. So, all the signal transferring is happening in space. Thus this type of communication is known as space communication. Two satellites which are commonly used in satellite communication are Active and passive satellites.

Passive satellites: It is just a plastic balloon having a metal coated over it. This sphere reflects the coming microwave signals coming from one part of the earth to other part. This is also known as passive sphere. Our earth also has a passive satellite i.e. moon. Active satellites: It basically does the work of amplifying the microwave signals coming. In active satellites an antenna system, transmitter, power supply and a receiver is used. These satellites are also called as transponders. The transmitters fitted on the earth generate the microwaves. These rays are received by the transponders attached to the satellite. Then after amplifying, these signals are transmitted back to earth. This sending can be done at the same time or after some delay. These amplified signals are stored in the memory of the satellites, when earth properly faces the satellite. Then the satellite starts sending the signals to earth. Some active satellites also have programming and recording features. Then these recording can be easily played and watched. The first active satellite was launched by Russia in 1957. The signals coming from the satellite when reach the earth, are of very low intensity. Their amplification is done by the receivers themselves. After amplification these become available for further use.

Features of satellite communications: Satellites used in satellite communications are usually in geostationary orbit. Some of them are placed in highly elliptical orbits. Satellite communications can provide global availability. It can not only land masses but also maritime areas as well. Large distances can thus be covered quiet easily. One of the main advantages provided by satellite communication is the superior reliability unlike other forms of communication. It does not need terrestrial infrastructure for operation. Satellite communication could provide superior performance as uniformity and speed are much more pronounced than other forms of communication. Scalability is higher in case of satellite communications. Deployment cost is higher than most forms of communications in case of satellite communications. As it is less vulnerable than other forms of communication, it is highly used in defense departments. Satellite communications also provide weather information. It can be helpful during times of disasters as the services rarely fail. High amount of data can be transmitted with the help of satellites.

Block Diagram

An earth station transmits information signal to the satellite using a highly directional dish antenna. The satellite receives this signal, processes it and transmits it back at a reduced frequency. The receiving earth stations will receive this signal using parabolic dish antennas pointed towards the satellite. The signal which being transmitted upwards to the satellite is called as the "up-link" and it is normally at a frequency of 6 GHz. The signal which is transmitted back to the receiving earth station is called as the "down-link" and it is normally at a frequency of 4 GHz. Thus a satellite has to receive, process and transmit the signal. All these functions are performed by a unit called satellite transponder. A communication satellite generally has two sets of transponders, each set having 12 transponders making it a total of 24 transponders. Each transponder has a bandwidth of 36 MHz which is sufficient to handle at least one TV channel. The up-link signal received by a transponder is a weak and down-link signal transmitted by the transponder is strong. Therefore to avoid interference between them, the up-link and down-link frequencies are selected to be of different value The operation of satellite takes place at a very high signal frequencies in the microwave range.

Geostationary (GEO) Satellite The satellites orbiting in the geostationary orbit are called geostationary satellites. They travel at the velocity of revolution of earth, hence complete one revolution around the earth in oner day i.e. 24 hours. This is the reason why geostationary satellites appear to be stationary. The geostationary satellites are also called as GEO satellites.They are basically used for communication applications. These satellites are at about 36000 km above the earth's surface. There are certain advantages of such a high altitude such as: The solar cells get the solar radiation for almost 99% of the orbital period. Therefore energy storage is not necessary. The earth's magnetic field is weak at such heights. Therefore the adverse effects of magnetic field are absent. Large coverage area. A geostationary satellite is visible from about 42% of the earth's surface area. Therefore three communication satellites can cover the entire surface area of the earth as shown in the fig.

The elements of satellite communication system Earth Station Terrestrial System User

Thank You