Bi spends much of his time in the CDMA Performance Lab, working to verify CDMA system performance and devising ways to improve related algorithms.

Bell Labs' Qi Bi: A Wireless Pioneer
January 10, 2003
by Rebecca Scott
Bell Labs

Years later, Bi not only works at Bell Labs, but recently received the institution's top honor -- recognition as a Bell Labs Fellow -- for his pioneering contributions in the areas of analysis, design and optimization of code division multiple access (CDMA) mobile communications systems. His influential work was pivotal to the company's decision to support CDMA as a second-generation wireless standard and has contributed to Lucent's success in digital wireless communications.

"Being selected as a Fellow is a true honor, but it would not have been possible without the work of many others in my organization," said Bi, a technical manager in Mobility Solutions' systems engineering group in Whippany, N.J. "This tribute gives me a greater sense of my role in helping to carry on the rich tradition that past Bell Labs pioneers have created."

According to Bi's supervisor, Patrick Li, director, AMPS/PCS BS Systems Engineering in Whippany, Bi is not only at the top of his field, but is a role model when it comes to collaboration and teamwork. "Qi is always willing to share his considerable insights with others," Li said. "His judgment of what is realistic comes from both extensive theoretical modeling as well as field experience. Many people focus on just one or the other -- Qi does both very effectively."

Pioneering Work on CDMA
Bell Labs began to look into CDMA, a digital wireless system that uses mathematical codes to transmit information, as a digital communication option in 1990. That's when Bi volunteered to join the research team working to evaluate the feasibility of CDMA.

"At that time, mobile communications systems were all analog," Bi said. "They weren't very efficient, so we began to look at designing wireless systems that would have greater capacity."

The pursuit of CDMA was not very popular at the time, but the team saw promise in CDMA and began a number of detailed studies. Based on the results of CDMA studies, Bell Labs and Qualcomm decided to cooperate on a technology roadmap.
In the early '90s, much of the effort to improve wireless capacity was focused on the reverse link of the system -- from the mobile phone to the cell site. Bi and his team were among the first to realize that the limiting link was actually the forward link -- from the cell site to the mobile phone. This was a key breakthrough and soon led to the desired improvement in efficiency.

Looking Beyond 3G
"It's amazing how much progress we've been able to make on CDMA in the last 10 years," Bi said, "from architectural definition to algorithm development to prototyping to standardization."

Currently, Bi is responsible for the evaluation and algorithm design of third-generation wireless systems, including, CDMA2000 and 1xEV-DO. "That we are already looking beyond 3G, I find incredible," he said.

"Qi's work has a direct impact on Lucent's customers," Li added. "His team constantly proposes performance improvements that help make and keep Lucent base stations best in class. And his interaction with our customers has helped establish Lucent's reputation as the leader in spread-spectrum technologies."

Bi enjoys working at Bell Labs and looks forward to many more years here. "I've been lucky to have many wonderful mentors who have given me guidance and direction throughout my career. I would not be where I am today without all of their help," Bi said. "The Bell Labs working environment is incredible, and I am lucky to be a part of it."

Bi (center) has made pioneering contributions in the areas of analysis, design and optimization of CDMA mobile communications systems. Bi is seen here with Mobility Solutions colleagues (from left) Neil Bernstein, Asif Gandhi, Bob Funk, and Ellen Farrey-Goudreau, in Whippany’s CDMA Performance Lab.