Patent ID: 7215883

Claim:
A method of determining the performance of an optical communication channel, the method comprising the steps of: a) receiving light signals conveyed over said optical communication channel at a photodetector; b) generating, by means of said photodetector, a first electrical signal to be used to provide a measure of average received optical power in said light signals received at said photodetector in step (a); c) generating an average current signal from the first electrical signal; d) generating the measure of the average received optical power from the average current signal with an average current measuring circuit; e) generating, by means of said photodetector, a second electrical signal, separate from the first electrical signal, from said light signals received at said photodetector in step (a); f) generating a data signal from the second electrical signal; and g) monitoring changes in said measure of average received optical power as represented by said first electrical signal in step (b) to determine the performance of the optical communication channel.