1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Radiowave reflection

  1. Nov 15, 2011 #1
    1. The problem statement, all variables and given/known data
    As shown in the attachment, a radio signal travels down a tunnel, reflected by the walls and floor. Assuming that at most 2 hops contribute, calculate the voltage Vab at A due to current Ib in antenna B. Obtain a formula that depends on various parameters of the problem.


    2. Relevant equations
    Assuming antennas are polarization matched, the voltage Vab in receiver antenna A (effective length Ha) is given by Vab=Ha*Eb,
    where Eb (the field at A due to source at B) and
    Eb=((jωμIbHb)/4∏)*(exp(-jβd)/d) (where β is wavevector, d distance between A and B)

    3. The attempt at a solution
    What I have got is for single reflection, the field at A due to source at B is Eb=R*((jωμIaHa)/4∏)*(exp(-jβd)/d) where R is reflection coefficient of ground and d the reflected distance. But for multiple reflection, just like shown in the graph, how I can get the field at A?
     

    Attached Files:

  2. jcsd
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?