Table of Contents

Satellite Communications

Orbital Needs of Canadian Telecommunications

Teacher Background

A major portion of this activity consists of independent research by the students in the preparation of materials for discussion, debate or negotiation. This teacher background outlines the basic information needed with respect to the content, communications satellites, and with the preparation of the activity. More background information including preliminary concept maps associated with this topic may be found in the resource Space Age Telecommunications in Canada; the student sheets from this resource would be useful for this activity.

A very valuable piece of real estate exists off Earth. In fact it is a region of space, an orbit, approximately 35,000 km from Earth's surface, at the equator. This orbit is unique because, at that distance, satellites orbit Earth once a day and therefore do not appear to move relative to Earth's surface. This orbit is critical for applications such as telecommunications where fixed orientation ground-based receivers (such as digital TV receivers) can be affordably mass produced. Receivers that need to track satellites are more complex and expensive. The only other major users of this orbit are global weather satellites. Surveillance satellites, global positioning satellites and others tend to use lower orbits.

The following table summarizes the name, controlling country and longitude of the communications satellites over the Western Hemisphere (61 degrees west longitude to 120 degrees west longitude). To obtain an understanding of how crowded this orbit is, the students could plot the position of each of these on a scale drawing. The major players in the development of telecommunications satellites in the Western Hemisphere are Canada and the United Sates. Canada, the US, Mexico and Brazil are the major users.

WESTERN HEMISPHERE
(geostationary satellites from 61W to 120W)

Informational websites that, at the teacher's discretion, may be used by students in their research include:

• Telesat Canada: http://www.telesat.ca
  
  
• Intelsat: http://www.intelsat.com
  
  
• GOES Weather Satellites: http://www.ghcc.msfc.nasa.gov/GOES
  
  
• International Telecommunication Union: http://www.itu.int/home/index.html
  
  

Teacher Background for Debate

This information is for a modified version of formal debate. For more information or resources contact the debate coach in your, or a neighboring school.

A debate is a structured argument between two teams of two debaters. There is usually one team arguing for the resolution (affirmative) and one team arguing against the resolution (negative). The affirmative team must prove the resolution and the negative team must rebut or dispute the resolution. A resolution usually suggests a change to the status quo and the affirmative must make a case for why such a change is needed. It is the role of the negative team to prove that the status quo is fine and that change is not required.

For the purposes of this resource a modified version of the formal style of academic debate has been suggested.

Order of speeches: The affirmative team has the first and the last word. The constructive speeches during which the debaters build their cases alternate between the teams "affirmative", "negative", "affirmative", "negative". The rebuttals alternate between the teams "affirmative" "negative", "affirmative".

Speaking Times: For this modified debate each constructive speech should last for no longer than 2 minutes. The rebuttal speeches should last for 2 minutes each. With these time limits one debate should take about 15 minutes so you will need 3 class periods to get through them all (for a class of 32). Day 1 do 3 debates, day 2 do 3 debates and day 3 do 2 debates and a debrief session.

Affirmative Team Role: In their constructive speeches the affirmative team must make the case for why the change suggested in the resolution is required. They also have the advantage of being able to define the terms in the resolution and the negative team must abide by those definitions. The affirmative team should also suggest a plan for how to carry out the change suggested by the resolution.

Negative Team Role: The main job of the negative team is to clash with or dispute every point brought up by the affirmative team. As well, they are expected to prove that there is no need for a change in the system, that the status quo is just fine.

Rebuttal Speeches: Here teams both rebuild their own arguments and attack the arguments raised by their opponents. This occurs in two stages: First a debater restates the point being disputed and then after identifying the argument must answer the point.