Electronics Letters | Year: 2014
There is a desire to overlay future optical access networks onto legacy passive optical networks (PONs) to provide increasingly advanced services by filling empty wavelength bands of legacy gigabit rate PONs. Nonlinear Raman crosstalk from new wavelengths onto legacy RF video services (1550-1560 nm band) and onto the legacy digital downstream at 1490 nm, however, can limit the number and the launch power of new wavelengths. As an example, straightforward physical-layer adjustments at the optical line terminal that increase the number of new, 10 Gbit/s channels launched in the 1575-1580 nm band by a factor of 16 without increasing the Raman penalty on the video signal are illustrated. A physical-layer (RF) filter modifies the on-off-keyed signal feeding each 10 Gbit/s transmitter, suppressing the RF Raman crosstalk on the video signal by 9 dB while incurring a power penalty on each 10 Gbit/s link of <0.5 (2.0) dB with (without) forward error correction. The previous Raman mitigation work used non-standard line-coding to shape the 10 Gbit/s electrical spectrum. In addition, polarisation-interleaving of new wavelengths lowers the worst-case RF DC crosstalk by ?3 dB in fibres and it limits and stabilises DC crosstalk in low polarisation mode dispersion fibre links. © The Institution of Engineering and Technology 2014.
NeoPhotonics | Date: 2013-07-26
Optical telecommunication receivers and transmitters are described comprising dispersive elements and adjustable beam steering elements that are combined to provide optical grid tracking to adjust with very low power consumption to variations in the optical grid due to various changes, such as temperature fluctuations, age or other environmental or design changes. Thus, high bandwidth transmitters or receivers can be provides with low power consumption and/or low cost designs.
NeoPhotonics | Date: 2015-05-06
A method of manufacture of an integrated circuit coupling system includes: forming a waveguide assembly, having a top clad over an open end of an optical core; forming a first photoresist having a base photoresist pattern shape with sloped photoresist sidewalls tapered down to expose a portion of the top clad; forming a recess having clad sidewalls from the portion of the top clad exposed by the base photoresist pattern shape, the clad sidewalls having a shape replicating a shape of the base photo resist pattern shape; and forming an optical vertical insertion area, from the clad sidewalls forming the recess, having a pocket trench, a horizontal step, and a mirror with a reflective material selectively applied to a section of the clad sidewalls and exposing the open end opposite to the mirror, the horizontal step between the mirror and the pocket trench.
NeoPhotonics | Date: 2014-10-06
A multiple-output laser component is described with a plurality of diode lasers in a common package, each of the diode lasers having distinct electrical control and optically coupled to a distinct output fiber, the component configured such that up to a maximum total output power can be selectively and dynamically partitioned among said diode lasers. The dynamic allocation can be based on demand for laser power in a fiber optic coupled to each diode laser. The multi-output laser component can be used to drive amplifiers associated with a multicast switch in some embodiments.
NeoPhotonics | Date: 2014-10-20
Telecommunications switches are presented, including expandable optical switches that allow for a switch of N inputsM outputs to be expanded arbitrarily to a new number of N inputs and/or a new number of M outputs. Switches having internal switch blocks controlling signal bypass lines are also provided, with these switches being useful for the expandable switches.