A pilot tone generator receives optical energy from an optical
communication medium carrying a plurality of optical signals. Each
optical signal carries data modulated at a unique wavelength and further
modulated with a unique identification signal. The identification signal
has an amplitude corresponding to an optical power of the associated
optical signal. The pilot tone receiver detects each identification
signal from the optical energy received and determines its corresponding
amplitude. The pilot tone receiver calculates the optical power of each
optical signal in the optical energy in response to the amplitude of the
associated identification signal.