I also attended Globecom this year in Anaheim, CA, on Thu and Fri and mainly focused on following the recent advances in energy-efficient network designs.
On Thur morning, I presented a research paper about Energy-Efficient MU-MIMO in the “Energy Efficiency in Access Networks” session and listened to several other presentations. The research results presented in this session covered issues from PHY layer all the way up to network deployment, which is expected as energy is consumed by protocols of all layers. While most of them are based on well-known ideas like dynamic/static BS management, power allocation, sleep mode, etc, there’re some interesting new concepts. For example, the sleep mode can be improved to consider the QoS (though I’m questioning if a device is sleeping, who will care about the QoS… ). A student from Cioffi’s group presented a paper about intelligent power save mode design for devices connected to 802.11 WLAN. The battery life can be improved more than 1/3 especially when the packet arrival rate is low and the packet idle durations are long. It shows a good way to go when we consider connecting IoT devices through WLAN.
On the afternoon, I chaired a session, together with Oliver Blume from Bell Labs, on Green Cellular Wireless Communications. This session was even more interesting. There’re many new ideas about what we can do to save energy consumption for cellular networks. For example, energy-efficient beamforming, EE femtocell power optimization, utilization of stochastic geometry, and dynamic system bandwidth management. The interests came from both academia and industry and there were lots of questions/discussions in this sessions. The presentation by Oliver was especially interesting (slides attached below). He showed that by adapting the system bandwidth and # of operating circuits according to traffic load, a significant amount of energy can be saved. The difficulties however lie in the design and implementation of adaptive hardware, which were unfortunately not discussed. This is one way to go, but definitely the only one. We should pursue more better solutions.
Friday was for tutorials and there were some good ones. For example, “Interference Alignment: State of the Art” by Syed A. Jafar and “Opportunistic Communication: Unified View and New Applications” by Aria Nosratinia, both cover the respective areas very well. However after some offline discussions, it seems the interference alignment doesn’t gain much momentum in industry because of the high complexity in the implementation. But will complexity always be a bottleneck? We have Moore’s law…
On Fri afternoon, I presented a tutorial about Joint PHY-MAC Design for Spectral- and Energy-Efficient Wireless Networks. This tutorial summarizes spectral and energy efficient communication technologies for both individual and multi-user networks.