Optical Phase Demodulators
DPSK Demodulator
DQPSK Demodulator
90-Degree Optical Hybrid
2x4 QPSK Mixer
2x8 QPSK Mixer
10G DPSK Demodulators
2.5G DPSK Demodulators
Optical Interleavers
Tunable Optical Filters
Optical Monitors
Integrated High-Speed Receivers
Optical Test & Measurement
Optical Spectrum Analyzers
Lasers and Light Source
F-P Etalons Products
Custom-Design Products
Home > Products > Optical Phase Demodulators > 2x4 QPSK Mixer
2x4 QPSK Mixer  
Optoplex QPSK Mixer - Polarization Diversified Optical Hybrid
Optoplex QPSK Mixer - Polarization Diversified Optical Hybrid
PDF Datasheet
  • Description
  • Features
  • Applications
  • Specifications
Product Description - QPSK Mixer - Polarization Diversified Optical Hybrid

Optoplex's 2X4 polarization diversified optical hybrid (aka QPSK Mixer) is a 2x4 device, which mixes an incoming signal with a local oscillator. The 4 outputs of this device are connected to 4 single-ended detectors (see the function diagram below). The device features a monolithic optical core integrating a PBS with an interferometer which is also widely used in Optoplex's interleaver and DPSK-demodulator platforms. This device is athermal, colorless, data-rate independent, compact in size and designed for manufacturability. This platform can also be extended to a 2X8 polarization diversified hybrid to incorporate with 4 pairs of balanced detectors.

The QPSK mixer is a key building block of the ever-popular polarization- and phase-diversified QPSK modulation scheme which is not only one of the leading contenders for the 100-Gb/s systems but also a awesome alternative for the 40-Gb/s systems with the potential of utilizing 10-Gb/s modulator and electronics.

Principle of Optoplex QPSK mixer

For 90° Optical Hybrid, please visit Optical Hybrid page.

Features and Benefits of QPSK Mixer
  • Purely passive device (no need for external electric power)
  • Compact size
  • Based on free-space bulk-optics design
Applications of QPSK Mixer
  • For the next-generation optical transmission system
  • Key component for the optical coherent detection (a detection format which has been widely used in many other communication methods, such as radio and wireless)
Standard Specifications of DQPSK Demodulator




Wavelength Range (C-Band) nm 1527 ~ 1567
Phase Difference1 (between Ik and Qk), k=x or y degree 90±10
Insertion Loss1 (not including connector) S (polarization scrambled) to All Outputs dB 9.5 ~ 11.5
L (45° linear polarized) to All Outputs dB 9.5 ~ 11.5
Insertion Loss Uniformity1 Among S to All Outputs; Among L to All Outputs  dB <0.7
Among All Others dB <1.0
Optical Return Loss dB >27
Optical Path Difference1 (Skew, among Sà All Outputs) ps <1
Optical Path Difference1 (Skew, among Là All Outputs) ps <1
Polarization extinction ratio1 (for either S or L) dB >18
Max. Input Optical Power mW 300
Operating Temperature Range °C 0 ~ 65
Storage Temperature Range °C -40 ~ 85
Size (L x W x H)2 mm 48 x 31 x 10
Fiber Type (for S, Ix, Iy, Qx, Qy) - SMF-28 with 900 mm tight buffer
Fiber Type (for L) - PM with 900 mm loose tube
Fiber Pigtail Length m TBD
Connector Type - TBD

  1. Over the stated spectral and operating temperature ranges and all polarization states.
  2. Not including six collimator sleeves extending from one longer side by ~18 mm.

Product Request and Ordering Information
Please speak to Optoplex Sales persons. If you request custom-designed QPSK mixer product, please provide the following parameters:
  • Wavelength range
  • Fiber length
  • Optical connector type