EARS: Enhanced Spectrum Availability and MU-MIMO Coordination for High Spatial-Spectral Efficiency

在多用户MIMO系统中已经实现了惊人的频谱效率，超过了每赫兹每秒40比特。不幸的是，在空间、频率和时间上促进传输所需的协调会严重限制效率。此外，许多频谱现在被认为是不可用的，即使附近没有活动的接收器，因此资源根本无法使用。该项目融合了三个综合推力，以实现高频谱空间效率(每平方米每赫兹每秒比特)和高频谱可用性(允许在特定位置的特定频段内传输)。首先，该项目通过开发智能主接收器实现了一种新的频谱可用性模式。关键的想法是，典型的主要频谱发射机，如电视广播公司，并不是在所有位置都有活动的接收器。这一推力实现了一种用于智能主接收器的架构和算法，以通知控制器其使用情况，从而创建大量新的动态可用的空间频谱资源。其次，该项目克服了目前频谱接入所需的协调方面的基本限制。这一推力认为，通道探测和用户-状态协调是系统设计的基础资源，本身必须进行分配。针对协作受限的MU-MIMO协议，提出了一套完整的新方法。最后一项重点是实施和测量研究。这一推力产生了第一个由智能主用户增强的频谱接入的演示，以及第一个通过协调有限协议机制增强的多用户MIMO分集频谱系统。该平台通过使用最大放大的信号和从塔楼到用户再到室内无线局域网的真实场景，以“大规模”实验为目标。

Astounding spectral efficiencies exceeding 40 bits per second per Hertz have already been achieved in multi-user MIMO systems. Unfortunately, the coordination needed to facilitate transmissions in space, frequency, and time can severely limit efficiency. Moreover, many spectral bands are today deemed unavailable even if no active receiver is nearby and hence resources cannot be used at all.This project fuses three integrated thrusts towards achieving high spectral-spatial efficiency (bits per second per Hertz per square meter) with high spectrum availability (permission to transmit in a particular band at a particular location). First, this project enables a new mode of spectrum availability by exploiting smart primary receivers. The key idea is that a typical primary spectrum transmitter such as a TV broadcaster does not have active receivers in all locations. This thrust realizes an architecture and algorithms for smart primary receivers to inform a controller of their usage, creating vast new dynamically available spatial-spectral resources. Second, this project overcomes fundamental limits in the coordination that is today required for spectrum access. This thrust considers channel sounding and user-state coordination to be a foundational resource of system design that must itself be allocated. An integrated suite of new methods for coordination limited MU-MIMO protocols is developed. The final thrust provides an implementation and measurement study. This thrust yields the first demonstration of spectrum access enhanced by smart primary users and the first multi-user MIMO diverse spectrum system enhanced by coordination limited protocol mechanisms. The platform targets "at scale" experiments via use of maximally amplified signals and real-word scenarios spanning from tower-to-user to indoor WLAN.