Describe in 1-2 sentences each the following terms: "Time of Arrival", "Time Differrence of Arrival", "Angle of Arrival", and "RSSI".

Which of these concepts is being used by GPS? How many satellites do you need at least to get a position? How many if you want to obtain elevation in addition to longitude and latitude?

How many channels are there in 802.11b that do not overlap? Why are these non-overlapping channels preferable over other channels?