We are experiencing today an explosion in wireless network traffic driven by the rapidly growing number of mobile devices and bandwidth hungry applications. Industry research predicts a 1000-fold increase in aggregate bandwidth demands by 2020. In spite of decades of research on improving spectrum efficiency in WiFi and cellular networks, existing techniques can only offer short-term solutions. The millimeter-wave (mmWave) technology, e.g., in the unlicensed 60 GHz band supported by the IEEE 802.11ad standard, has recently emerged as an alternative to legacy WiFi, promising multi-Gigabits per second throughput. Although the commercial use of 60 GHz hardware has been limited until recently to short-range line-of-sight scenarios, e.g., wireless docking, due to the high attenuation and vulnerability to blockage of mmWave signals, this project envisions the use of mmWave technology for building general purpose, multi-Gigabit wireless Local Area Networks for home and enterprise environments that will offer always-on connectivity but an order of magnitude higher throughput than today's 2.4/5 GHz WiFi networks. One major factor that has hindered research efforts towards this vision is the lack of testbeds due to the unavailability of 60 GHz hardware that can simultaneously offer both high performance and high levels of reconfigurability and control. This project will build X60, a software defined based 60 GHz testbed that will offer high level of reconfigurability at the PHY, MAC, and network layer, and, at the same time, support channel widths and speeds commensurate to those of the IEEE 802.11ad standard.
Each testbed node consists of an FPGA-based mmWave Transceiver from National Instruments integrated with a 12-element phased antenna array from SiBeam Inc. With no other testbeds of similar capabilities available in the wireless networking community, the use of FPGAs lends full flexibility and enables one to implement a broader range of communication and networking solutions, ranging from the current standard itself to radically new communication and networking solutions. Starting from the broadband characterization of the channel, innovative modulations that maximize the spectral efficiency and new physical layer (PHY) synchronization mechanisms will be developed as part of this project. At the Medium Access Control (MAC) layer, novel beam forming/beam steering and rate adaptation algorithms as well as loss differentiation algorithms will be studied. At the network layer, the project will investigate the use of wireless relays and smart reflector arrays to improve connectivity, coverage, and network capacity, as well as explore a radically new integrated PHY/MAC cross-layer architecture founded on soft code-division multiplexing/multiple access principles - an approach fundamentally different from that of the IEEE 802.11 standards. The project will make the the developed software for the X60 testbed and the measurement data generated from research projects enabled by this infrastructure available to the wireless networking community.
