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Welcome to the public review site of papers appearing in MobiSys 2012. Here you can find the public review written by a PC member for each paper and the authors' rebuttal to it. You can comment on any of them or add your own opinion. Finally you can vote to "like" or "dislike" a paper by clicking the up or down arrows next to its title.

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[–]JacobSorber 0 points1 point ago

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Question: Can you explain why FM variations are smaller than WiFi? Are there weather dependencies?

Answer: Most of our datasets were collected over three months, during the Summer. They include a lot of weather variation (rain, sun). We also took continuous FM measurements for certain fixed locations, and the variation seems to be small.

As for why the lower variations: I can't prove it, but my intuition is that the lower frequencies are less susceptible to things like multipath.

[–]JacobSorber 0 points1 point ago

sorry, this has been archived and can no longer be voted on

Question: Why use the two combined? Why not just use FM? How do you use this practically? Size of antenna?

Answer: I don't recommend using FM alone. FM is good for differentiating two locations within the same building, but it is sometimes difficult to differentiate between two locations in different nearby buildings. Also, we used an antenna that was twice the size of the phone in our experiments. There are smaller patch antennas that are very small and can easily fit into a phone, but we didn't have these available to include in our experiments.

[–]JacobSorber 0 points1 point ago

sorry, this has been archived and can no longer be voted on

Question: What about cities with dense antennas or fewer transmitters?

Answer: Our dataset is limited to only a few cities, so I can't generalize. Information about the number and location of FM transmitters is also publicly available for many cities.