Gee-Kung Chang, Ph.D.

Optical Networking
Georgia Institute of Technology
Recruited: 2002

One day in the not-too-distant future, your mobile device will have wireless access to an incredibly powerful communications network, with lightning-fast data and split-second feedback – up to 100 times faster than today's.
This network won’t just make it easier to browse the web or download digital data and movies. It will also enable sweeping transformations in how “smart” our communities and devices can be. Imagine advances like traffic alerts that signal you about accidents as they’re happening nearby and direct you with an up-to-the-second alternate route. Or hyper-local tornado warning systems that offer customized guidance on the fastest way to safety.
This is the dream of the 5G mobile data network, and G. K. Chang is working to deliver it. He and fellow researchers are developing a model for 5G that integrates fiber optics with wireless communication. Their approach would bring together optical fiber, the highest-bandwidth wires, with an unprecedentedly efficient use of the radio spectrum (from 0.1 GHz to frequencies as high as 110 GHz) for next-generation mobile networks.
The current mobile data model requires high-powered base stations that transmit over wide areas and long distances. By contrast, the model Chang favors would have smaller, simpler and more numerous access points or smaller cells – located in office parks, shopping centers, schools, even homes.
These wireless access points would be connected by fiber optic wires, enabling data transfer at a much faster rate. And with less air distance to cover, the new base stations could broadcast over a wider range of radio frequencies – including the high-frequency bands at centimeter-, millimeter-, and sub-Tera Hertz waves, where there's less interference at the cell-edge through coordinated multi-point transmission.
It might sound complex, but the end result would be pervasive: small unobtrusive base stations, and wires hidden in walls, ceilings, or underground.
Beyond his work in the lab, Dr. Chang is also a strategist and industry leader who serves as the director of both the NSF Industry/University Cooperative Research Center for Optical Wireless Applications and the Georgia Tech Center for Fiber Wireless Integration and Networking


Dr. Chang's lab designed and built a wireless over optical fiber testbed for next generation multi-gigabit wireless access networks for very high throughput video and data applications.

  • Integrating optical, microwave, and millimeter-wave transceivers into computer chips with high-density, high-speed optical interconnect technology (i.e., communication via optical waveguides and cables)
  • Demonstrating a high-density, high-speed 3-D optical interconnect system, constructed on a flexible, low-cost and lightweight substrate material
  • Designing an optical-label switching router for information packet forwarding and routing
  • Designing and building a super broadband, integrated fiber-wireless access network that can deliver both wireless and wired access bandwidth of more than 10 Gb/s per user over WDM-PONS (wavelength division multiplexed passive optical networks) and multi-tier radio access network (M-RAT) services using microwave photonics and radio wave over fiber (ROF) technologies  

Straight from the Scholar

After gaining 23 years of industry experience in R&D at Bell Labs, Bellcore, Telcordia Technologies, and OpNext, Dr. Chang was excited to enter the university environment where he could pursue his research at the leading edge of integrated optical and millimeter-wave networking technologies. Georgia Tech’s organizational mission is advancing the well-being of human condition through technology — a good place for Dr. Chang to pursue his own vision of improving the most speedily adopted technology in human history… optical fiber communications and the mobile data network. 

Intellectual Property

56 patents and co-authorship on 500+ peer-reviewed articles