Table 4.

Required system constant, K_s, for various combinations of design parameters at 1.5 μm.

Variant Number	Photodetector	Rio [A/W]	M	F	NEPm [ $\text{pW}/\sqrt{\text{Hz}}$ ]	ξ0	Kb [m2·nm·sr]	Required Ks [W·m3]
13	InGaAs APD	0.93	10	5.5	0.7	0.5	6.17 × 10−9	58.29
14	InGaAs APD	0.93	10	5.5	0.7	0.25	6.17 × 10−9	116.6
15	InGaAs APD	0.93	10	5.5	0.7	0.1	6.17 × 10−9	291.5
16	InGaAs PIN	0.93	1	1	7	0.5	6.17 × 10−9	530.7
17	InGaAs PIN	0.93	1	1	7	0.25	6.17 × 10−9	1061
18	InGaAs PIN	0.93	1	1	7	0.1	6.17 × 10−9	2654