Problem 2 Lloyd-Mirror and The Method of Images
Reading: COA 1.4.1, 1.4.2
a) Use equation 1.19 to calculate the pressure from a 150Hz point source located 25m
below the surface. Plot the magnitude of the pressure over the rectangular region r=10m to
r=1000m, z=0m to z=500m. (See Matlab psuedo-code at the end of this document for help.)
How many beams are there? How many would you expect to see, given Eq. 1.29 ? Make
another plot with the same parameters, but this time plot transmission loss (Eq 1.15)
instead of the magnitude of the pressure.
b) With the same frequency and source depth, plot the TL vs. range only (for a fixed receiver
depth of 200m, range varying from 10m to 8km). For comparison, plot the TL due to
spherical spreading in open space on the same plot. In other words, reproduce Fig 1.9 but
with a slightly larger range. Does spherical spreading, or Lloyd-Mirror drop off faster (in the
limit of a large range)? Why?
Problem 3: Plotting Reflection Coefficients
Problem 1.6 from COA.
Reading: COA 1.6 (especially 1.6.1)
