Figure 2

(a) The normalized power detected at the receiver positioned at an angle of 35.5° for a metal reflector (black circle), and angles corresponding to the primary lobes of the diffracted signal when the grating spacing is \(\Lambda =2.58\mathrm{ mm}\) (red circle). As the distance increases the attenuation of the signal is greater when using a diffraction grating than compared to a metallic reflector. The slope of the linear fit is 34.7 (dB/decade) for the signal diffracted by the grating (red line). The FSPL is also plot against the metal reflector data (blue line). (b) The measured BER for the uncompressed grating (red dots) is greater compared to a metal reflector (black dots) as the receiver distance is increased for a given transmitter power. The calculated BER for the metal reflector (blue line) only experiences FSPL and increases at a slower rate in comparision to the higher BER predicted for the signal from the diffraction grating (red line).