Abstract: An electronic device may be provided with an antenna having a resonating element formed from a segment of peripheral conductive housing structures. A speaker may be aligned with first openings in the segment. A vent may be aligned with second openings in the segment. A connector may protrude through the segment. A trace combiner for the antenna may be patterned onto the speaker and may be coupled to the segment. Tuners for the antenna may be disposed on first and second flexible printed circuits that extend along opposing sides of the connector. The tuners may be controlled through the speaker. The second flexible printed circuit may extend along the vent. The vent may have a vent cowling with a cut-out region next to the tuner on the second flexible printed circuit.

Abstract: An electronic device may be provided with an antenna having a resonating element formed from a segment of peripheral conductive housing structures. A speaker may be aligned with first openings in the segment. A vent may be aligned with second openings in the segment. A connector may protrude through the segment. A trace combiner for the antenna may be patterned onto the speaker and may be coupled to the segment. Tuners for the antenna may be disposed on first and second flexible printed circuits that extend along opposing sides of the connector. The tuners may be controlled through the speaker. The second flexible printed circuit may extend along the vent. The vent may have a vent cowling with a cut-out region next to the tuner on the second flexible printed circuit.

Abstract: Techniques are described for configuring an optical network unit (ONU) in a pre-burst state prior to transitioning the ONU to a burst-on state. During the pre-burst state, a laser emitter of the ONU stabilizes to its wavelength, thereby reducing the impact of wavelength drift when the ONU transitions to the burst-on state.

Abstract: Techniques are described for configuring an optical network unit (ONU) in a pre-burst state prior to transitioning the ONU to a burst-on state. During the pre-burst state, a laser emitter of the ONU stabilizes to its wavelength, thereby reducing the impact of wavelength drift when the ONU transitions to the burst-on state.

Abstract: Techniques are described for configuring an optical network unit (ONU) in a pre-burst state prior to transitioning the ONU to a burst-on state. During the pre-burst state, a laser emitter of the ONU stabilizes to its wavelength, thereby reducing the impact of wavelength drift when the ONU transitions to the burst-on state.

Abstract: Techniques are described for configuring an optical network unit (ONU) in a pre-burst state prior to transitioning the ONU to a burst-on state. During the pre-burst state, a laser emitter of the ONU stabilizes to its wavelength, thereby reducing the impact of wavelength drift when the ONU transitions to the burst-on state.

Abstract: In general, this disclosure relates to optical network devices with support for multiple physical layer transport standards. An optical network device may include an optical receiver that can be adaptively configured to support different physical layer transport standards. For example, the optical receiver may include a photodiode and a control unit to adjust a characteristic of the photodiode to support different optical physical layer transport standards on an adaptive basis. For example, the control unit may adjust the photodiode characteristic to prevent an overload condition when an optical signal is received according to the physical layer access standard.

Abstract: Techniques are described for maintaining the extinction ratio of an output optical signal over temperature and aging. In some examples, the techniques may determine the instantaneous slope efficiency of the laser outputting the optical signal, while the laser is outputting the optical signal. Based on the determined slope efficiency, the techniques may determine the needed drive current components (e.g., at least one of the bias current and the modulation current) that results in maintaining the extinction ratio to within a desired range.

Abstract: This disclosure relates to detection of optical fiber failure and implementation of protection switching in a passive optical network (PON). A protection switch determines whether there is an optical fiber failure in a fiber link between an OLT and a group of ONTs. In the case of an optical fiber failure, an optical fiber may be physically cut or damaged, causing the optical fiber link to be disabled. A protection switch may detect an optical fiber failure by determining a peak optical power of at least a portion of an upstream optical signal transmitted from one or more ONTs via the optical fiber link. If the peak optical power is less than a threshold value, the protection switch may detect a fiber failure. In response to a detected fiber failure, the protection switch may switch upstream and downstream PON transmissions from a primary optical fiber to a secondary optical fiber.

Abstract: In general, this disclosure relates to optical network devices with support for multiple physical layer transport standards. An optical network device may include an optical receiver that can be adaptively configured to support different physical layer transport standards. For example, the optical receiver may include a photodiode and a control unit to adjust a characteristic of the photodiode to support different optical physical layer transport standards on an adaptive basis. For example, the control unit may adjust the photodiode characteristic to prevent an overload condition when an optical signal is received according to the physical layer access standard.

Abstract: This disclosure is directed to techniques for facilitating return path compliance in networks. A device, such as an optical network terminal (ONT), may, for example, buffer a digital representation of an upstream analog signal to facilitate return path compliance specified by a Data Over Cable Service Interface Specification (DOCSIS) 3.0 standard. The ONT may comprise a first conversion module that converts an upstream analog signal into a corresponding digital signal and a signal detection module that determines whether the upstream analog signal represents a valid upstream communication. The device may further comprise a buffer that buffers the corresponding digital signal while the signal detection module makes the determination, a second conversion module that converts the buffered digital signal into a reconverted upstream analog signal upon the determination that the upstream analog signal is valid and a laser that transmits the reconverted upstream analog signal via a fiber optical cable.

Abstract: This disclosure relates to detection of optical fiber failure and implementation of protection switching in a passive optical network (PON). A protection switch determines whether there is an optical fiber failure in a fiber link between an OLT and a group of ONTs. In the case of an optical fiber failure, an optical fiber may be physically cut or damaged, causing the optical fiber link to be disabled. A protection switch may detect an optical fiber failure by determining a peak optical power of at least a portion of an upstream optical signal transmitted from one or more ONTs via the optical fiber link. If the peak optical power is less than a threshold value, the protection switch may detect a fiber failure. In response to a detected fiber failure, the protection switch may switch upstream and downstream PON transmissions from a primary optical fiber to a secondary optical fiber.

Abstract: This disclosure describes techniques for providing a communication path for upstream communications originating from a node of an optical network. In particular, methods and devices are described for combining upstream communications originating from the node of the optical network with upstream communications originating from subscriber devices coupled to the node. The upstream communication originating from the node may, for example, include status information about the node. The upstream communication, which may include status information about the node, essentially piggy-backs onto upstream communication originating from the subscriber devices coupled to the node.

Abstract: A method of determining liquid absorption of an aggregate comprises providing a sample of the aggregate, adding liquid to the sample, subjecting the sample to a light source signal, monitoring a light reflected signal reflected from the sample and controlling addition of liquid to the sample as a function of the light reflected signal. The apparatus comprises a support for supporting a sample of the aggregate, a liquid source for adding liquid to the sample, a light source which subjects the sample to a light source signal, a light sensor which senses a reflected light signal reflected from the sample and a processor/controller which controls addition of liquid from the liquid source as a function of the reflected light signal. The light source is preferably an infrared source and the light sensor is preferably an infrared detector.

Abstract: A method of determining liquid absorption of an aggregate comprises providing a sample of the aggregate, adding liquid to the sample, subjecting the sample to a light source signal, monitoring a light reflected signal reflected from the sample and controlling addition of liquid to the sample as a function of the light reflected signal. The apparatus comprises a support for supporting a sample of the aggregate, a liquid source for adding liquid to the sample, a light source which subjects the sample to a light source signal, a light sensor which senses a reflected light signal reflected from the sample and a processor/controller which controls addition of liquid from the liquid source as a function of the reflected light signal. The light source is preferably an infrared source and the light sensor is preferably an infrared detector.