A novel multi-ary PolSK modulation for smooth PON evolution

Multi-ary polarization shift keying (PolSK) modulation is proposed for smooth PON evolution. The new PON signal applies multi-ary PolSK to eliminate the induced crosstalk to the coexisting amplitude shift keying (ASK) legacy PON signal. Different from traditional PolSK, there are more than two polarization states in multi-ary PolSK, so it is able to provide a bit rate exceeding the bandwidth limit of current commercial transceivers. Four-ary PolSK is demonstrated and evaluated. The results show multi-ary PolSK supports high-speed signal in future PONs with very low crosstalk induced to the coexisting legacy PON signal.