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How can the satellite re-track

  1. Feb 13, 2009 #1
    hi every one

    I have tow quation about satellite, I have been searchinh for long time but I have not get the answer first. how can the satellite re-track to its orbit if it drifts?

    second what will the speed become if the satellite drifts to the east or west some distance. I mean the relashinship between drifted distance and speed
    thank you
     
  2. jcsd
  3. Feb 13, 2009 #2
    Re: satellite

    I don't think I understand your questions to the extent they were posed, here goes nothing.

    I am no expert, but couldn't a satellite triangulate its position from positions on the ground or other satellites? This could keep it at a designated orbit.

    As for your second question I have no idea what you are asking. the relationship between speed and distance is Velocity = Distance/Time. that would be a scalar approach so you could use your position coordinates and do the vector math.
     
  4. Feb 13, 2009 #3
    Re: satellite

    First of, what kind of satellite are you talking about?

    Here try this, let's say that satellite X1 is must be found at 76 degrees west, between Y1 at 74 degrees and Z1 at 81 degrees.

    This means that X1 is two degrees west of Y1 and 5 degrees east of Z1. Since we're dealing with a total of 7 degrees, two degrees is about one-third of the way from Y1 towards Z1.

    Now we look at the 4-digit positions listed for Y1 and Z1 in the [Satellite] menu. Let's say that Y1 is at 4260, and Z1 is at 4290.
    There are 30 digits between 4260 and 4290, right? So look for X1 one-third of the way between Y1 and Z1, at 4270.
    Select X1 from your main [Satellite] menu so you're watching it. You must be watching the satellite you want to move.
    Go to [Menu 7]. Move your cursor to [Position].
    Press [Enter] to allow you to change the position.
    Enter the digits 4270 using the keypad on the heel of your remote control.
    When the dish arrives at the selected position, look for a which is not scrambled.
    If you get a weak or no signal, try another channel which should be unscrambled. Using the [Left} and
    arrow/cursor keys, scan slightly left and right until you see a signal, then hit [Autotune] to let the receiver position the dish for in the satellite. (NOTE: make sure the program you see is correct for the satellite desired. If not, you are on a different satellite, so keep looking.)
    Hit [Menu][Menu] to save the new dish position.
    With the cursor pointing to [Position], press [Autotune] to have the receiver fine-tune the dish position. Put the cursor on Polarity and hit Autotune to set the polarity.

    Or you can check out this website http://www.satcodx1.com/eng/
     
  5. Feb 13, 2009 #4

    mgb_phys

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    Re: satellite

    If you mean how can it move back into the correct position - it has rocket engines.
    Satelites drift out of position because it is impossible to place them in exactly the correct orbit, it's alos necessary to boost satelites in low earth orbit because they are slowed down by the outer edge of the earth's atmosphere. Finally you occasionally need to move a satelite out of the way of another satelite or some junk.

    The problem is that this isn't like a driving a car, you can't turn on the motor, move a bit and stop, when you turn off the motor you will continue moving until you fire the motor in the opposite direction. Then you don't move east-west, you move to further out orbits to go slower and lower orbits to go faster. Finally you have a very limited amount of fuel on board and so every movement must be carefully planned.
     
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