Incoherent & Coherent Detection Comparisons

9104-002

Direct Detection:

                                                 (MRi)2Pr
CNR = ------------------------------------------------------------
             [2e{Ri(1+NbBo/Pr)+Id/Pr}M(2+x)+(4kTF/RL)/Pr]Be

Heterodyne Detection:

                                                               (MRi)2Pr
CNR = ---------------------------------------------------------------------------------
             [e{Ri(1+Pr/Po+NbBo/Po)+Id/Po}M(2+x)+2(MRi)2Nb+(2kTF/RL)/Po]Be

Homodyne Detection:

                                                                2(MRi)2Pr
CNR = ---------------------------------------------------------------------------------
             [e{Ri(1+Pr/Po+NbBo/Po)+Id/Po}M(2+x)+2(MRi)2Nb+(2kTF/RL)/Po]Be