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

在多用户MIMO系统中，已经实现了超过每秒每赫兹40比特的惊人频谱效率。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，即使附近没有主动接收器，许多频谱带也被认为是不可用的，因此资源根本无法使用。该项目融合了三个集成的重点，以实现高频谱空间效率（每平方米每赫兹每秒比特数）和高频谱可用性（允许在特定位置的特定频段传输）。首先，该项目通过利用智能主接收机实现了一种新的频谱可用模式。关键的思想是，一个典型的主频谱发射机，如电视广播电台，并不是在所有的位置都有主动接收器。该推力实现了智能主接收器的架构和算法，以通知控制器它们的使用情况，创造了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。这个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，必须自己分配。开发了一套集成的新方法来协调有限的MU-MIMO协议。最后的推力提供了一个实现和测量研究。这一推力产生了由智能主用户增强的频谱接入的第一个演示，以及由协调有限协议机制增强的第一个多用户MIMO多样化频谱系统。该平台的目标是“大规模”实验，通过使用最大程度放大的信号和从塔到用户到室内WLAN的真实场景。

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.