Power Radiated by a Leaky Waveguide
Arttu Luukanen (NIST)

Computer simulation
This plot represents the power radiated by a waveguide that has three holes drilled into its side. A traveling wave of microwave radiation propagates along the waveguide and each hole couples out a fraction of the power. The direction of the maximum emission of the holes is determined by the separation between the holes, as this separation governs the directions of constructive and destructive interference. The plot represents the direction of emitted power (horizontal axis) versus the separation of the holes (vertical axis). Leaky waveguides can do many things, including detect dangerous bacteria.