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How to Select a PBC/PBS for High-Bandwidth Systems

2025-11-12

High-bandwidth systems need clean, stable, and predictable light paths. When your design depends on strong polarization control, a PBC or PBS becomes one of the most important components in your link. These devices keep the polarization states separate or combine them efficiently so your system can move more data with less noise and fewer errors. Choosing the right Polarization Beam Combiner/Splitter helps your design stay steady even as speeds rise and requirements become tighter. 

A careful selection process makes sure your PBC/PBS supports your bandwidth, handles your power, and maintains strong performance under real operating conditions. 

In this blog, we will discuss: 

  • What a PBC/PBS does in high-bandwidth systems 
  • Key performance factors to check 
  • How to match the device to your fiber and wavelength 
  • When polarization stability becomes essential 
  • How to choose for high-power or long-distance links 

 

What a PBC/PBS Does in High-Bandwidth Designs 

A Polarization Beam Combiner/Splitter manages two orthogonal polarization states. A PBC combines them into one output. A PBS separates them into two outputs. High-bandwidth signals depend on stable polarization because advanced modulation formats use polarization to move more information through the link. 

If the polarization state becomes unstable, the system may lose speed, increase error rates, or show unpredictable signal behavior. A well-chosen PBC/PBS helps you reduce these risks and keep your design performing as expected. 

 

Check the Insertion Loss and Isolation 

Insertion loss and isolation play a big role in high-bandwidth work. 

Low insertion loss
A low loss value helps more power reach the receiver. High-bandwidth formats often need stronger and cleaner signals, so low loss becomes important. 

High isolation
Isolation helps the device keep the two polarization states separate. Strong isolation reduces leakage and prevents unwanted cross-talk between channels. 

If you want stable performance, you want a PBC/PBS with tight control over both parameters. 

 

Match the Device to the Right Wavelength 

You want your Polarization Beam Combiner/Splitter to match your operating wavelength or wavelength band. High-bandwidth systems often run in the C-band or L-band. A mismatch may create loss, reflection, or drift. 

Check these details before selecting a device: 

  • Wavelength range 
  • Center wavelength 
  • Spectral bandwidth 
  • Temperature stability of these values 

The right wavelength match supports cleaner and more stable performance. 

 

Look at PER and Polarization Stability 

High-speed systems depend on strong PER and steady polarization. This becomes even more important when your design uses coherent detection or advanced modulation formats. 

A strong PER helps your system: 

  • Reduce polarization-related noise 
  • Keep bandwidth consistent 
  • Maintain a predictable signal path 

If your design uses PM fiber, you want a PBC/PBS that supports it with consistent axis alignment. 

 

Consider Power Handling for High-Power Systems 

You want to check the power rating if your system uses high optical power. Some PBC/PBS devices support only low or moderate power. Others handle higher power with better thermal control. 

Make sure the device can: 

  • Handle your continuous and peak power levels 
  • Manage heat without drifting 
  • Maintain isolation under load 

This keeps your system safe and stable as power rises. 

 

Match the Device to Your Fiber Type 

You want your PBC/PBS to match the fiber in your system. A mismatch can create loss, alignment problems, and long-term stability issues. 

Check these details: 

  • Fiber size and type 
  • PM or non-PM fiber 
  • Connector type 
  • Pigtail length 

A correct match gives you cleaner integration and reduces installation stress. 

 

Choose Based on Application Requirements 

Different applications use PBC/PBS devices differently. 

Coherent communication systems 

These systems depend heavily on polarization control. A high-PER PBC/PBS becomes essential. 

Fiber sensing systems 

Stable splitting helps sensors stay accurate across long distances. 

High-power fiber lasers 

A PBC helps combine signals efficiently as power increases. 

DWDM and long-haul links 

Strong isolation helps reduce noise and keeps the channels clean. 

Once you know your application, you can choose a device that supports it more effectively. 

 

Final Thoughts 

Selecting a PBC/PBS is a simple process once you know the performance needs of your system. When you check loss, isolation, PER, wavelength, and power handling, you can choose a Polarization Beam Combiner/Splitter that supports clean, stable, and high-bandwidth operation. With the right device in place, your system gains the reliability and performance it needs for real-world conditions. 

 

FAQs  

  1. Why do I need a PBC or PBS in my system?

You need it to control two polarization states. It helps your system send or split light in a clean way. 

  1. Does a PBC/PBS make the signal faster?

No. It does not make the signal faster. It keeps the polarization steady so your high-speed system works better. 

  1. What happens if I choose the wrong device?

You may get more loss, more noise, or unstable signals. Choosing the right device helps you avoid these problems.