Optical-to-wireless WDM converter

• US 20040234273A1
• Filed: 06/21/2004
• Published: 11/25/2004
• Est. Priority Date: 06/29/2001
• Status: Active Grant

• Current Assignee: HRL Laboratories LLC (The Boeing Co.)
• Original Assignee: HRL Laboratories LLC (The Boeing Co.)
• Inventors: Izadpanah, Hossein, Sayyah, Keyvan, Pepper, David M.
• Granted Patent: US 7,292,791 B2
• Time in Patent Office: Days
• US Class Current: 398/149
• CPC Class Codes: H04B 10/25752 Optical arrangements for wireless networks
• CPC Class Codes: H04B 10/60 Receivers
• CPC Class Codes: H04B 10/64 Heterodyne , i.e. coherent receivers where, after the opto-electronic conversion, an electrical signal at an intermediate frequency [IF] is obtained

Abstract

In a method and apparatus for converting optical wavelength division multiplexed channels to wireless channels, the information carrying optical carriers are first de-multiplexed and each optical carrier is then extracted from the data using an optical channelizing technique. The optical frequency of each of the extracted optical carriers is then shifted by an amount equal to the desired wireless carrier frequencies in the broadband wireless channels. Optical heterodyning of the frequency-shifted extracted lightwave carriers with the original data-containing optical signals, which are mutually in phase coherence, in a photodetector results in a set of wireless carriers each modulated with the data carried by the corresponding optical channel.

Claims

1-86. -86. (canceled)

87. An optical channelizer filtering optical data signals to extract unmodulated optical carriers, wherein the optical data signals comprise modulated optical carriers generated by a master mode-locked laser, and the channelizer comprises:

an optical combiner combining the optical data signals into a composite optical signal; and

a slave mode-locked and injection-locked laser receiving the composite optical signal, the slave laser being set to be below threshold and breaking into a mode-locked oscillation condition to generate an optical signal containing the unmodulated optical carriers.

88. The optical channelizer according to claim 87, wherein the slave laser has a controllable cavity length.

89. A method of filtering a composite optical signal to extract unmodulated optical carriers, wherein the composite optical signal contains a plurality of optical data signals comprising modulate optical carriers generated by a master mode-locked laser the method comprising

coupling the composite optical signal to a slave mode-locked injection locked laser with a controllable cavity length;

controlling the cavity length of the slave laser to cause it to break into a mode-locked oscillation condition, the oscillation condition creating an optical output signal comprising unmodulated optical carriers; and

coupling the optical output signal from the slave laser.

90. The method according to claim 89, wherein the controllable cavity length is controlled by a piezoelectric-driven mirror or an intracavity electro-optical phase shifter.