Abstract: An apparatus for providing auxiliary signals on a high speed electrical signal network is provided such that the auxiliary signals may be used for independent monitoring or communication of monitored information without affecting data or bit error rates for the primary high speed data signals. The auxiliary signals may be used as part of a built-in testing of a network, including electrical time-domain reflectometry measurements to determine fault locations in a network.

Abstract: An apparatus is provided that is capable of achieving bidirectional, full-duplex communication with an optical transceiver. In some instances, the communication is achieved over a single electrical connection of the transceiver and via the use of a duplexing circuit on the transceiver and a complementary duplexing circuit on a distal circuit coupled to the transceiver via the single electrical connection. The techniques described may be used to modify existing optical transceivers to provide diagnostic or health information without interrupting normal transceiver operation.

Abstract: A bidirectional fiber-optic transceiver with lower optical loss than previous beam-splitters or fiber couplers and a method of implementing the same. Preferably, the transceivers can operate in both directions using a single-wavelength of electromagnetic radiation.

Abstract: An apparatus to measure optical characteristics of a fiber optic transmission line or other optical medium may include a source to generate a bipolar pulse signal waveform. The apparatus may also include a mixer to mix the bipolar pulse signal waveform and an optical pulse and reflected signal waveform from the fiber optic transmission line or other optical medium to form a mixed product waveform, wherein the reflected signal is responsive to the optical pulse being transmitted into the fiber optic transmission line or optical medium.

Abstract: Apparatus and methods for improved fiber optic signal transmission systems are disclosed. In one embodiment, a reflectometer includes an optical source to emit optical energy into a the fiber optic line and to generate time-delayed signals from the repetitive pulses, an optical receiver to detect reflected energy from the fiber optic line and generate reflected signals from the reflected energy, a mixer that receives the reflected signals and receives the time delayed signals to generate a product waveform from the reflected signals and the time-delayed signals, and a processor that receives the product waveform to process the waveform to generate a value based on the sampled characteristic.

Abstract: Bi-directional optical signal transmission apparatus and methods are disclosed. In one embodiment, an optical detector is configured to receive an optical signal from an end of an optical fiber. An optical element is located at the detector surface and is configured to receive and direct a laser beam. A laser beam is directed by the optical element through the end into the optical fiber substantially parallel with the principal axis.

Abstract: Apparatus and methods for capacitively coupled device input/output are disclosed. In one embodiment, a connector module includes a first member having at least one first conductive lead disposed therein. A dielectric portion is coupled to an end portion of the at least one first conductive lead. A second member has at least one second conductive lead disposed therein. The first and second members are coupled such that respective end portions of the first and second conductive leads are operatively positioned and spaced apart by the dielectric portion. The dielectric portion is adapted to capacitively couple the respective end portions of the first and second conductive leads and to allow signals to be transmitted therethrough.

Abstract: An inexpensive optical time domain reflectometer is disclosed that comprises a variable delay device and that is capable of identifying the location of a damage portion of a fiber optic cable with great accuracy and minimal power consumption. A method of providing a vehicle with an on-board optical time domain reflectometer is also disclosed.

Abstract: A fiber optic communication system is provided that includes a light source adapted to emit a system optical signal and an electrical signal source adapted to provide a data input electrical signal. Additionally, the fiber optic communication system includes a feed forward photonic modulation circuit adapted to receive the data input electrical signal and the system optical signal and output a final modulated optical signal substantially free from residual error.

Abstract: Apparatus and methods for fiber optic links having a built-in test are disclosed. In one embodiment, an optical component includes a signal source, and a controller operatively coupled to the signal source. The signal source is adapted to output a first combined optical signal having a first optical signal portion of a first frequency and a second optical signal portion of a second frequency. The first frequency is substantially greater than the second frequency. The controller is adapted to induce the signal source to output the first and second optical signal portions, the first optical signal portion being associated with a main communication function and the second optical signal portion being associated with a monitoring function.