Since 2013, when he first arrived as Rice University, Kaipeng Li has worked alongside Joseph R. Cavallaro, the director of the Center for Multimedia Communications (CMC).
“Rice is very famous for electrical engineering, especially digital signal processing. Our work lies in the wireless communications area. I was enthusiastic about doing research that matched my background and interests, and Rice has given me that opportunity,” said Li, a sixth-year graduate student in electrical and computer engineering (ECE).
In November, Li completed a three-month software engineering internship with Google.
“Kaipeng is an exceptionally creative student who is able to connect advanced wireless algorithms with cutting-edge parallel GPU computing systems,” said Cavallaro, professor of ECE and Li’s doctoral adviser.
In collaboration with Cavallaro, Li’s recent research has focused on “massive MU-MIMO,” short for “multi-user multiple-input multiple-output,” a transmission scheme that uses base stations with hundreds of antennas to simultaneously serve multiple users on the same frequency. The object is to boost the aggregate network capacity by several degrees and increase connectivity and signal strength for telephones and other mobile devices.
Massive MU-MIMO permits optimal spatial reuse, increased power efficiency and reduced inter-user interference. In the past, the capacity of conventional, small-scale MIMO wireless systems was limited by available spectrum and transmission power. Recent research in the field of information theory has suggested that such limits on capacity can be overcome by exploiting spatial reuse through massive MU-MIMO technology.
“Our work has been developing efficient algorithms and creating hardware prototypes. The value is, it’s a decentralized and scalable approach to tackle implementation challenges in typical massive MU-MIMO with centralized signal processing. We can easily add more antennas to make the system even larger,” Li said.
In October, Li won second place in a student paper contest at the Asilomar Conference on Signals, Systems, and Computers in Pacific Grove, Calif. He was the lead author in writing “Feedforward Architectures for Decentralized Precoding in Massive MU-MIMO Systems.” His co-authors are Charles Jeon, a graduate student in ECE at Cornell University; Cavallaro; and Christoph Studer, assistant professor of ECE at Cornell.
Cavallaro said of Li’s contributions to the project: “Our CMC group has made many contributions to wireless algorithms and testbed through the years. Kaipeng’s research on decentralized baseband processing will have a huge impact on accelerating processing and reducing latency in new wireless base-stations containing hundreds or thousands of antennas.”
Li was born and raised in Jinan, a coastal city in China that is the capital of Shandong province. His father is a businessman and his mother a machinist.He earned his B.S. in physics from Nanjing University in 2013. In addition to Google, Li has had internships at Baidu USA and IBM, and co-authored five journal papers and nine conference papers. The thesis he wrote to earn his master’s degree at Rice was titled “GPU Accelerated Reconfigurable Detector and Precoder for Massive MIMO SDR Systems.”
After graduation next spring, Li expects to work in industry. “Professor Cavallaro is a very nice guy. He gives us a lot of freedom and great suggestions on research. He also prepares us well for working in industry,” Li said.