US Federal Government Spectrum Monitoring by Mr. Michael Cotton
Tutorial of the Spectrum Observatory and a Walkthrough of the Technology by Mr. Anoop Gupta
Beyond Sensing: Multi-GHz Realtime Spectrum Analytics by Mr. Lixin Shi, MIT
Spectrum sensing has been an active research area for the past two decades. Nonetheless, current spectrum sensing systems provide only coarse occupancy data. They lack information about the detailed signal patterns in each band and can easily miss fleeting signals like radar.
We present SpecInsight, a system for acquiring a detailed view of 4 GHz of spectrum in real-time. SpecInsight’s design addresses the intrinsic conflict between the need to quickly scan a wide spectrum and the desire for obtaining very detailed information about each band. Its key enabler is a learned database of signal patterns and a new scheduling algorithm that leverages these patterns to identify when to sample each band to maximize the probability of sensing active signals.
SpecInsight is implemented using off-the-shelf USRP radios with only tens of MHz of instant bandwidth, but is able to span 4 GHz of spectrum, and capture very low duty-cycle signals in the radar band. Using SpecInsight, we perform a large-scale study of the spectrum in 6 locations in the US that span major cities and suburban areas, and build a first-of-its-kind database of spectrum usage patterns.
Integrated Sensing and Database Architecture for White Space Networking by Dr. Sumit Roy, University of Washington
The evolution of cognitive (secondary) networks to enable more efficient spectrum usage will rely on fast and accurate spectrum sensing/mapping, supported by a suitable architecture for data integration and model building. In the first part of the talk, fundamental aspects of the wide-area RF mapping problem as a grand challenge will be highlighted; and some recent work at UW that underpin sub-system level trade-offs (between scan latency and channel status estimation accuracy) for channel sensing described. Next, the role of centralized databases in RF map creation for enabling primary-to-secondary and secondary-to-secondary coexistence is explored and a hybrid architecture proposed – that involves both distributed (crowd-sourced) local sensing as well as it’s integration into databases. Finally, some ongoing work regarding a fundamental question: how much white space capacity is actually available – will be described.
TxMiner: Identifying Transmitters in Real-World Spectrum Measurements
How should regulators re-assign spectrum optimally? How do licensees identify spectrum usage in order to provision for future needs? How do Dynamic Spectrum Access devices determine on which frequency to operate? All these questions require knowledge about active transmitters, which is not straight-forward to obtain with currently-existing techniques. In this talk I am going to present TxMiner: a system that automatically identifies transmitters without prior knowledge of their characteristics. TxMiner makes use of machine learning methods in order to tease apart transmitters from raw spectrum measurements. I will start by outlining several key insights that enable TxMiner; I will then show results from transmitter identification using traces collected by Microsoft’s Spectrum Observatory.
Towards Commoditized Real-time Spectrum Monitoring
We are facing an increasing difficult challenge in spectrum management: how to perform real-time spectrum monitoring with strong coverage of deployed regions. Today’s solutions use dedicated hardware that is bulky and expensive, making the monitoring task extremely difficult and cost prohibitive. We propose a practical alternative by leveraging the power of the masses, i.e. millions of wireless users, using low- cost, commoditized spectrum monitoring hardware. We envision an ecosystem where crowd sourced smartphone users perform automated and continuous spectrum measurements using their mobile devices, and report the results to a monitoring agency in real-time.
In this talk, we will introduce our initial feasibility study to verify the efficacy of the mobile monitoring platform compared to that of conventional monitoring devices. Our results indicate that commoditized real-time spectrum monitoring is indeed feasible in the near future. We conclude by discussing a set of open challenges and potential directions for follow-up research.
An Overview of the Global Policy and Regulatory Landscape – Opportunities and Risks for Alternative Forms of Spectrum Access
It has been three decades since the United States Federal Communications Commission (“FCC”) created the first unlicensed spectrum access. Although only available commercially in the last fifteen years, it is hard to imagine consumers doing without technologies now used in the unlicensed spectrum bands – Wi-Fi, Bluetooth, RFID. There are now many more wireless devices reliant on unlicensed access to spectrum than wireless devices reliant on licensed access to spectrum. Driven by growing demand that risks outstripping the current allocations of spectrum for wireless broadband applications, governments and regulators around the world are now looking at making more spectrum available on an exclusive-use licensed basis for 4G LTE, as well as make more spectrum available on an unlicensed (or licensed-exempt) basis for Wi-Fi and other technologies. Governments and regulators are likewise now looking at alternative forms of spectrum access which will not require incumbent licensees to be cleared and reallocated, such as spectrum sharing opportunities in the TV white spaces, 2.3 GHz, 3.5 GHz, and 5 GHz either on an unlicensed, licensed, or lightly-licensed basis. This presentation will provide an overview of efforts by governments and regulators around the world to address these issues – with a particular focus on alternative forms of spectrum access. This presentation will also discuss how spectrum observatories, standardization, technology trials, commercial pilots, partnerships, and industry and academic coalitions can and are being used to support these efforts.