Radio Astronomy - power received

AI Thread Summary
The discussion revolves around calculating the power received from a geostationary satellite with a 1 W transmitter over a 1000 square km footprint. Participants express confusion about how to determine the total power collected, noting the need for additional information such as the area of the receiving antenna. The conversation highlights the importance of understanding the relationship between the satellite's transmission and the radio telescope's energy collection since 1950, assuming a uniform flux density. There is an emphasis on needing to estimate both the telescope's area and bandwidth for accurate calculations. Overall, the thread seeks guidance on how to approach these calculations effectively.
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Homework Statement


Compare this to the power received on the ground from a geostationary satellite with a 1 W transmitter and with a transmission footprint of 1000 square km across (assume uniform power in footprint).


The Attempt at a Solution


I don't know where to start on this one pretty much. I mean I know that it is transmitting 1 W of power and that the intersection of this beam with the Earth's surface is 1000 square km, but I just don't know how I would go about determining the total power collected. There must be something that I'm missing because from the amount of marks allocated for this question you wouldn't receive 1 W of power. Any hints on what to do would be greatly appreciated.

Cheers
 
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Compare WHAT with the power received from a 1W transmitter? I think you truncated the question.
 
Yeah I did truncate the question, but it's not the comparing part that I'm concerned with. I'm just wanting to get a push in the right direction as to how I would calculate the power received by the satellite.

But maybe the first part really does have something to do with it. The first part was this:

Estimate the total energy collected by a radio telescope since 1950 assuming that the sky emits a uniform flux density of 1 Jy.

So for that part I had to assume the area of the telescope and assume the bandwidth that was used too.
 
Then I think you want to compare that with the energy it would receive from said satellite. The question as stated doesn't give, or give you a way to guess the area of the antenna.
 
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