Desired to Undesired (D/U) Signal Ratio

Desired to Undesired (D/U) Signal Ratio

The desired signal is one that reaches the receiver where it may be decoded. The undesired signal is one that is reflected and may indirectly reach the receiver or get lost. Decoding the undesired signal may introduce multipath errors in the measurement of distance and signal strength. International Civil Aviation Organization has specified that the minimum desired to undesired (D/U) signal ratio should be 20 dB (ICAO, 2012). Graph shows D/U signal ratio per a material.