Abstract: Wavelength division multiplexing (“WDM”) passive optical networks (“PON”) to transport signals having various access platforms are described. For one embodiment, a WDM PON performs bi-directional communications, and includes an interface. The interface transfers one or more signals having a first platform to a WDM-PON data transmission platform at an access point of a network to propagate through a single transmission medium, to one or more remote distribution nodes in between a Central Office and an optical network unit. The single transmission medium carriers three or more optical channels traveling in both directions.

Abstract: Various methods and apparatuses are described in which data transmission in two or more discrete wavelength bands are routed in the same transmission direction between a central office and a remote node in a wavelength-division-multiplexed passive-optical-network (WDM PON). The two or more discrete wavelength bands are separated by at least ten nanometers in wavelength spectrum. Further, each wavelength band contains two or more optical wavelength channels within that wavelength band.

Abstract: Various methods, systems, and apparatuses are described in which a wavelength-division-multiplexing passive-optical-network includes a wavelength-locked light source and a wavelength-specific light source. The wavelength-locked light source may be used for communications in a first direction in the wavelength division multiplexed passive optical network to supply data signals at a first data rate. The wavelength-specific light source may be used for communications in a second direction in the wavelength division multiplexed passive optical network to supply data at a second data rate.

Abstract: An optical heterodyne detection system includes a tunable optical pre-selector that is adjusted to track the frequency of a swept local oscillator signal. The tunable optical pre-selector is adjusted in response to a measure of the frequency of the swept local oscillator signal and in response to a measure of a portion of the swept local oscillator signal after the portion of the swept local oscillator signal optically interacts with the pre-selector. Additionally, the pre-selector is dithered such that a dither is imparted on the portion of the swept local oscillator signal that interacts with the optical pre-selector.

Abstract: Various methods and apparatuses are described for a multiple wavelength light source. The multiple wavelength light source may be located in a central office to supply a first broad band of wavelengths for a one or more passive optical networks. The multiple wavelength light source generates a series of four or more pulses of light in the first broad band of wavelengths. Each pulse of light in that series has a different center wavelength. The series of pulses of light in the first broad band of wavelengths may be repeated at a channel data rate of an optical receiver at a subscriber's location.

Abstract: Various methods and apparatuses are described in which an array of optical gain mediums capable of lasing are contained in a single integral unit. The array may contain four or more optical gain mediums capable of lasing. Each optical gain medium capable of lasing supplies a separate optical signal containing a band of wavelengths different than the other optical gain mediums capable of lasing in the array to a first multiplexer/demultiplexer. A connection for an output fiber exists to route an optical signal to and from a passive optical network.

Abstract: An acousto-optic filter includes an optical fiber with a longitudinal axis, a core and a cladding in a surrounding relationship to the core. The optical fiber has multiple cladding modes. At least one acoustic wave generator is included and made of a sufficiently high frequency piezoelectric material to produce a longitudinal acoustic wave. An acoustic wave propagation member has proximal and distal ends. The distal end is coupled to the optical fiber and the proximal end is coupled to the acoustic wave generator. The acoustic wave propagation member propagates the longitudinal acoustic wave from the proximal to the distal ends and excites the longitudinal acoustic wave in the optical fiber.

Abstract: At least one non-reciprocal rotation element is interposed between two adjacent walk off crystal members to form an optical isolator. Light in the forward direction is separated into two rays of linear polarizations where there is substantially no optical path length difference between the two rays. Light transmitted in the reverse direction is reduced. A conventional optical isolator which does not preserve optical path length difference is converted into one which does by adding a birefringent plate to compensate for the optical path length difference introduced by the conventional isolator. A pair of collimating lenses may be introduced between any pair of non-reciprocal rotation elements.