Optimization of large-scale fiber sensor arrays incorporating multiple optical amplifiers. Part II: pump power

For part I see, ibid., p. 218, 1998. We discuss how to minimize the pump power required for large-scale fiber sensor arrays employing erbium-doped fiber amplifier (EDFA) telemetry with respect to the number of amplifiers per bus, number of sensors per rung, and the gain per amplifier. For a large array, the pump power requirement is dominated by passive component losses along the array. We investigate several methods, including alternative array topologies, to reduce the power requirement while minimizing the impact on the signal-to-noise ratio (SNR). We define an optimum topology which requires less than 1 W of 1480 nm pump power per bus to support 200 high sensitivity (1 /spl mu/rad//spl radic/(Hz)) sensors on a pair of fiber buses, a power requirement that is reasonable and attainable with available laser diodes.