1 / 8

Ensuring Capabilities Via Spectrum Access : Meeting the 21st Century Mission Dr. Larry B. Stotts

DoD Spectrum Symposium 14-15 October 2009. Ensuring Capabilities Via Spectrum Access : Meeting the 21st Century Mission Dr. Larry B. Stotts Deputy Director, Strategic Technology Office Defense Advanced Research Projects Agency.

ilya
Download Presentation

Ensuring Capabilities Via Spectrum Access : Meeting the 21st Century Mission Dr. Larry B. Stotts

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. DoD Spectrum Symposium 14-15 October 2009 Ensuring Capabilities Via Spectrum Access: Meeting the 21st Century Mission Dr. Larry B. Stotts Deputy Director, Strategic Technology Office Defense Advanced Research Projects Agency The views, opinions, and/or findings contained in this article/presentation are those of the author/presenter and should not be interpreted as representing the official views or policies, either expressed or implied, of the Defense Advanced Research Projects Agency or the Department of Defense Approved for Public Release, Distribution Unlimited

  2. Network Centric Wireless OperationsTechnical Challenges How do we enable reliable communications in urban areas where signals are scattered by buildings and terrain? How do we provide reliable spectrum access and coexistence for thousands of RF-based systems? How do we enable networks to scale to a large number of users and adapt to users’ mobility? How do we provide interoperability and reliable networking among the hundreds of US Military, Coalition, & Public Safety radio types? How do we provide content to soldiers at an affordable cost? How do we reliably deliver information and sustain networks despite frequent network disruptions? JTRS GMR Military • MIL-STD • 2 channels • High Cost, Low Volume • Voice & Data SATCOM PRC 117 Cellular COTS Apple iPhone • Commercial Stds • Multi-channel • Low Cost • Rich User Content Coalition Public Safety EPLRS 2

  3. RADIO LIMITATIONS Link Outages LOS Routing Bandwidth Quality of Service (QoS) Radio Command and Control Dissemination to Disparate Groups NETWORK COMPENSATION Disruption Tolerance LOS / NLOS Routing / Rerouting Spectral Re-Use and Routing Prioritization / Retransmission Control Plane Multicast / Unicast Why are These Challenges? The Network May Overcome Radio Limitations

  4. Next Generation (XG) Technologies and System Concepts for Dynamic Spectrum Access Unused Spectrum Changes in Time and Space Capability to Integrate Software with Existing Legacy Radios Frequency (MHz) Time of Day (Sec) PRC-148 JEM PRC-152 Falcon-III • Goals • Demonstrate Factor of 10 Increase in Spectrum Access • Demonstrate Enhanced Robustness by Interference Avoidance (Radios, Radar, Jammers, etc.) • Mechanism for “Bandwidth on Demand” thru Dynamic Provisioning Static Spectrum Management is Limited in Its Ability to Improve Spectrum Utilization Efficiencies – Currently ~ 6% Utilization TODAY: Spectrum statically allocated XG Wideband Prototype XG can operate across currently partitioned spectrum allocations OBJECTIVE: Dynamically allocating spectrum in frequency, space, and time XG Wideband Sensor 90-95% not being used!

  5. XG/DSA Proven Potential PRC-152 PRC-148 XG Wideband Prototype WNaN XG/DSA Demonstrated Ability to be Implemented in Current and Future Network Systems

  6. Mobile Networked MIMO (MNM) Field Test ResultsExceeded All Program Goals Exploiting the surrounding landscape to provide more robust, higher data rate links that work well in complex urban environments

  7. Disruption Tolerant Networking Reliable Communications Across Intermittent and Disrupted Tactical Networks DTN is developing network protocols and interfaces to provide high reliability communications over intermittent and disrupted links Better reliability in service scenarios Reliable On-The-Move edge-to-edge Delivery in Disrupted Networks Networking without Infrastructure 3.5x Increase in EPLRS capacity 3x bandwidth reduction for C2PC using stateful compression “Communications is the lifeblood of command / of a special forces team / of intelligence/ of what we do...” - from Report on “Coalition Operations in Operation Iraqi Freedom”, 27 Aug. 2007 Aggregate Delivery: DTN vice E2E IP in a permanently partitioned network Per-NodeDelivery: DTN vice E2E IP in a permanently partitioned network End-to-End IP Only DTN with IP DTN delivers 100% after nominal latency IP delivers immediately or never Fort AP Hill Nov. 2007 IP doesn’t and can’t deliver from disconnected nodes

  8. Frequency Power Time TDMA/FDMA Frequency Power Time DARPA Interference Multiple Access (DIMA) • Current State of Networking Technology • Current communication networks use the interference avoidance paradigm, which fundamentally limits overall network performance, i.e. network capacity and user throughput. • Interference avoidance relies on spectrum allocation methods that limits users to partial use of the spectrum and require a controlling entity to manage channel access. 802.11 Media Access Control (MAC) Protocol • DIMA Technology Advancement • Exploit multi-access interference through Multiuser Detection (MUD) allowing multiple users to simultaneously occupy the same channel. • Enables high capacity mobile ad-hoc spread spectrum communications without infrastructure or power control DIMA Digital Receivers 0 dB* signal 1 signal 2 signal 3 signal 4 -3 dB* Current method: conventional signal 1 signal 2 signal 3 signal 4 -6 dB* signal 1 -9 dB* Multi-user based algorithm signal 2 signal 3 signal 4 Demonstrate a mobile ad hoc spread spectrum communications network that requires no infrastructure and has 3X the aggregate capacity of 802.11 or IS-95 8

More Related