PowerLine Telecommunications (PLT); Coexistence of Narrow Band PLT technologies operating in the frequency bands 3kHz to 95 kHz, 95 kHz to 125 kHz and 125 kHz to 140 kHz; [IEEE Std 1901.2TM - 2013, IEEE Standard for Low-Frequency (less than 500 kHz) Narrowband Power Line Communications for Smart grid Applications, Section 10 Coexistence]