13 September 2011

Oclaro adds 100Gbps coherent receivers for transmission networks using PM-QPSK modulation

Oclaro Inc of San Jose, CA, USA, which makes optical communications and laser components, modules and subsystems, has launched the CR5100 series of 100Gbps coherent receivers.

The firm claims that the new receivers provide a compact and cost-effective solution to implement coherent communication using the polarization multiplexed quadrature phase-shift keying format (PM-QPSK, or DP-QPSK), which is the modulation scheme of choice for metro and long-haul optical transmission. Oclaro is previewing the new receivers in booths 1368 & 1370 at the European Conference and Exhibition on Optical Communications (ECOC 2011) in Geneva, Switzerland (19–21 September).  

“By leveraging our expertise in indium phosphide integration and our proven track record in developing coherent solutions for high-speed networks, we’ve been able to significantly lower the footprint of these receivers, which frees up valuable space for adding more functionality to customers’ modules and line cards,” says Yves Hardy, senior director of Transmission Product Management.

The new 100Gbps coherent receiver is used in transmission networks that employ the PM-QPSK modulation format. The CR5100 series (together with the CR5040 Series for 40Gbps PM-QPSK) is designed to be compliant with the OIF Implementation Agreement OIF-DPC-RX-01.0, a collaborative forum to which Oclaro has been a key contributor. The receiver is also available in a much reduced form factor for users that want to benefit from this next-generation footprint. Oclaro says that the design provides a compact and cost-effective solution for implementing coherent transponders using PM-QPSK, minimizing chromatic dispersion impairments and improving the spectral efficiency of existing fiber infrastructure.

The CR5100 100Gbps coherent receiver uses Oclaro’s indium phosphide (InP) technology to implement the optical hybrid phase mixers with integrated waveguide photodetectors, and employs high levels of functional integration on InP to minimize cost and enable high-volume manufacture. The electrical outputs of the balanced waveguide photodetectors are then coupled to a pair of dual-input linear transimpedance amplifiers (TIAs). The coherent receiver has several electrical control features to optimize the performance of the TIAs, such as bandwidth control and manual gain adjustment. The 32 GBaud output from the receiver is then coupled to the input of the subsequent ADC/DSP IC.

The functional components of the receiver are assembled in a miniature ceramic package, which is less than a half of the minimum footprint defined by the OIF. InP-based photonic integration enables a significant increase in density on the module or line card, says Oclaro. The miniature package is also available with an adaptor PCB for users that prefer compliance to the form, fit and function defined by the OIF Implementation Agreement.

Oclaro is currently sampling the CR5100 series of 100Gbps coherent receivers to tier-one systems and module manufacturers, with production release scheduled for later this year.

Tags: Oclaro 100Gbps coherent receivers

Visit: www.ecoc2011.org

Visit: www.oclaro.com