The proliferation of mobile devices is driving an ever-increasing demand on the capacity of infrastructure wireless networks, especially WiFi. The current wireless networks can hardly meet this demand because they are interference limited -- per-user throughput decreases super-linearly with network density. Adding more access points (APs) may worsen the problem, because the APs themselves interfere with each other. The objective of this research is to overcome this fundamental limitation, and enable network capacity to scale proportionally with node density, by exploring a transformative architecture called Scalable Distributed MIMO (SDM). The principle behind SDM is to reorganize the APs into clusters. Within each cluster, the APs tightly synchronize and share data with each other. This enables them to cancel the mutual interference and scale network capacity with AP density. Different AP clusters contend for channel access in a self-organized manner, thus scaling capacity across an entire network. The long-term objective of SDM is to enable dense indoor infrastructure networks supporting Gbps per-user throughput, marking an important step towards the goals outlined in the National Broadband Plan.
To realize the SDM principle, the proposed research synthesizes a comprehensive framework of tasks including performance modeling/analysis, network protocol/algorithm design, and implementation/experimentation on a software radio testbed. In particular, the PI plans to (i) systematically explore ways of deploying AP clusters to balance the tradeoffs between system complexity, scalability, and compatibility with legacy networks; (ii) design a new paradigm of cluster-centric network protocols that feature tight coordination between APs within a cluster and self-organization among different clusters; (iii) develop new communications algorithms that tame the coordination overhead while maximizing cluster capacity, and translate the capacity gain into improved end-user experience. The testbed used in the research tasks will be extended into a user-friendly educational platform that enhances the knowledge of wireless networks for students at different levels. The research and educational materials will be broadly disseminated for reproducibility of results.
01/2020, MobiCom'20 papers: millimeter-wave networking for an array of phased phased arrays; MIMO mmWave measurement study based on the M-Cube software radio.
06/2018, MobiCom'18 paper: UbiG system for efficiently coordinating the directional beams among mmWave access points.
11/2015, INFOCOM'16 paper: uplink signaling protocol for distributed MIMO (network MIMO).
06/2015, MobiCom'15 paper accepted!
03/2015, MobiHoc'15 papers accepted!
11/2014, IPSN'15 paper accepted!
06/2013, NEMOx and AFC papers accepted to MobiCom'13. These are the basis of the SDM project.
04/2016, Software Release: 802.15.4 (ZigBee) and 802.11b (WiFi) library for the WARP software radio (easily portable to GNURadio). This is the code base for our Halma project (IPSN'15).
Before downloading the software, please accept the following conditions:
(i) The software is for non-commercial use only.
(ii) For any reuse or distribution, you must make clear to others the license terms of this work.
(iii) If you use it in your research work, please acknowledge the source and cite the appropriate paper(s) in the publication list below.
Detailed instructions are provided in the README file inside. For questions, please contact
Sanjib Sur.
11/2015, Software Release: a Multi-User MIMO OFDM library (in Matlab) for the WARP software radio. This implements a simplified version of 802.11ac. It is the code base for most of our recent works in MIMO and multi-user MIMO. The Matlab code can be easily ported to all other software radio platforms like GNURadio.
Before downloading the software, please accept the following conditions:
(i) The software is for non-commercial use only.
(ii) For any reuse or distribution, you must make clear to others the license terms of this work.
(iii) If you use it in your research work, please acknowledge the source and cite the appropriate paper(s) in the publication list below.