Wireless Sensor Network Fundamental?

I am currently investing the topic: Wireless Sensor Network. Specifically, I need to show the calculation of how much power received against distance between the transmitter and receiver in WSN. However, I don't have any background to it. I am only asking help to get me started on this topic.

So, what is the basic formula of power transfer between transceivers?

This might be what you are looking for.

http://en.wikipedia.org/wiki/Friis_transmission_equation

You can solve for Pr for the receive power or Pt for the transmit power and R is the distance.

This equation has antenna gain and frequency factored in so I'm not sure if there is a more simplified version with just power and distance.

Hope this helps you get started at least!

The basic equation for free-space transmission link loss between two isotropic antennas is: -

Link Loss (dB) = 32.45 + 20$log_{10}$(F) + 20$log_{10}$(d)

where F is MHz and d is distance between the two antennas (kilometres).

If your antennas have gain then this improves things. If you are transmitting around a building it gets worse. A good estimate for the received power needed at a receiver is this: -

Power required in dBm is -154dBm + 10$log_{10}$(data rate) dBm

If the data rate is 1Mbps then the power required is -154dBm + 60dBm = -94dBm

See also this, this and this - these are similar answers I've given on other similar questions.