| 摘要 |
A heterodyne optical spectrum analyzer (10) is configured for analyzing spectral information of an optical input signal (15). The analyzer (10) comprises a local oscillator source (20) configured for generating an optical local oscillator signal (38). An optical mixer (25) is configured for receiving the input signal (15) and the local oscillator signal (38), and for outputting a plurality of different combined optical signals (50), each combined optical signal (50) being derived from the input signal (15) and the local oscillator signal (38). An opto-electrical receiver (30) having a plurality of inputs (52) is configured for receiving the combined optical signals (50) and for providing an opto-electrical conversion thereof, and an output (54) for outputting electrical signals representing the received combined optical signals (50). A signal processor (35) is configured for deriving spectral information of the input signal (15) by analyzing the electrical signals. The optical mixer (25) is configured for deriving a plurality of polarization diverse signals from the input signal (15), each polarization diverse signal having a different state of polarization, and deriving a set of balanced quadrature signals for each polarization diverse signal by combining each polarization diverse signal with a signal derived from the local oscillator signal (38). The derived sets of balanced quadrature signals represent the plurality of combined optical signals (50). |
