NeTS: Medium: Scaling WLAN Throughput and Range with Wide Aperture and 100x Spectrum Diversity

William Marsh Rice University, Houston TX

Investigators

Abstract

The driving vision of this project is to develop the foundations to scale line-of-sight (LOS) Wireless Local Area Networks (WLANs) to Terabit/second (Tbps) throughput and to exploit Tbps LOS interconnections to form distributed arrays in lower frequency bands. Namely, this project first targets to scale millimeter-wave networks with wide aperture LOS spatial multiplexing, thereby overcoming a fundamental limit of the lack of rich multi-path channels at high frequency. The second target is to overcome the inability of high frequencies to penetrate objects and the inability of lower frequency devices to have large arrays on a single client due to physical device constraints. Surmounting these obstacles enables formation of all-wireless distributed arrays with unprecedented properties. The proposed research agenda will enable new dimensions for scaling WLAN throughput and range.This project targets to impact spectrum policy via demonstration of novel usage cases of emerging and diverse spectral bands. This project will show how a design based on wide aperture enables high frequency bands to scale to achieve previously impossible capacity gains. This project will impact standards bodies as it will show how enhancements to existing standards and fusion of diverse bands can yield vast performance gains. This project will impact industry through demonstration of results coupled with the investigators' extensive collaborative industry network. Finally, the project includes an inter-disciplinary education plan and the team includes multiple Ph.D. students from under-represented groups. This project will provide two integrated fundamental advances towards realizing a vision of scaling WLAN throughput and range. The first project thrust is development and fabrication of a wide aperture millimeter wave interconnect with pico-second scale synchronization. The key technique is combining widely-spaced radiating elements into a synchronized and coherent line-of-sight spatially multiplexed transmission. Second, the project exploits the diverse properties of spectrum spanning two orders of magnitude (100 times or 100x). By coupling the aforementioned millimeter wave interconnect (operating at 30 GHz to 300 GHz) with legacy bands (500 MHz to 5 GHz), the 100x architecture will enable long-range spatially multiplexed object-penetrating links. The design will enable a device with a single legacy-band antenna to spoof legacy-band MIMO infrastructure into performing full-rank transmission and reception. A key project outcome will be experimental proof-of-concept demonstrations of all scaling principles and the first experimental realization of distributed legacy-band spatial multiplexing for single legacy-band antenna devices, a mode enabled by tightly synchronized distributed antennas with 100x spectrum diversity. Gigabit-per-second scale wireless transmission is now feasible: Driven by the wide spectrum availability at 60 GHz, multi-Gb/sec systems are already standardized in protocols such as IEEE 802.11ad and wireless HDMI and are available in commercial products and chipsets, including tri-band chips that support 60 GHz as well as legacy bands at 2.4 and 5 GHz. Moreover, the broad range of millimeter wave spectrum (30 GHz to 300 GHz) is considered a leading candidate by industry, regulators and the research community for the next generation of wireless systems. The project's objective is to realize the next order of magnitude in rate, directionality, and range, targeting both direct line-of-sight (LOS) paths and non-line-of-sight (NLOS) paths that must penetrate objects. The project's goal is to both explore the underlying foundations and to design and implement proof-of-concept systems to (i) realize a WLAN architecture that scales to Tbps via networked mm-wave antennas that form a large effective aperture and (ii) fuse diverse spectral bands spanning two orders of magnitude in order to scale client array size, and subsequently capacity, beyond the physical constraints of the device.