SDR Technology Implementation for the Cognitive Radio Bruce

SDR Technology Implementation for the Cognitive Radio Bruce Fette Ph. D Chief Scientist General Dynamics Decision Systems bruce. fette@gdds. com © 2003 General Dynamics, All rights reserved. 28 February 2021

Cognitive Radio* is Built on SDR* · We must start with a Software Defined Radio as a basic platform on which to build a Cognitive Radio · Cognitive Radio can provide the spectral awareness technology to support FCC initiatives in Spectral Use *SDR and Cognitive Radio are terms coined by Dr. Joe Mitola - see appendices for references © 2003 General Dynamics, All rights reserved. 28 February 2021 2

Definition of SDR · From FCC NPRM*: “We view software defined radios as the result of an evolutionary process from purely hardwarebased equipment to fully software-based equipment. In this regard, the process can be roughly described in three stages ä ä ä 1. Hardware driven radios: Transmit frequencies, modulation type and other radio frequency (RF) parameters are determined by hardware and cannot be changed without hardware changes. 2. Digital radios: A digital radio performs part of the signal processing or transmission digitally, but is not programmable in the field 3. Software Defined Radios: . All functions, modes and applications can be configured and reconfigured by software. *Notice of Proposed Rule Making (NPRM) 8/12/00 © 2003 General Dynamics, All rights reserved. 28 February 2021 3

Definition of SDR - Continued · SDR Forum: ä · 4. SW defines all waveform properties, cryptography and applications, is re-programmable, and may be upgraded in the field with new capabilities Importance of Standards (APIs) ä 5. HW Interfaces, RF services, Operating Environment, Application to Radio Interfaces © 2003 General Dynamics, All rights reserved. 28 February 2021 4

SDR Technology · Technology fundamentals: ä Digital Signal Processors (DSPs) provide virtually infinite programmability ä All modulation, cryptography, protocols, and source coding (voice, data, imagery) are established using software ä Many types of modulation can be accomplished over a broad range of frequencies, thereby an SDR is capable of servicing more than one class of service ä Field serviceable, when requirements change, upgrades and modifications are relatively easy to execute © 2003 General Dynamics, All rights reserved. 28 February 2021 5

SDR Standardized Architecture Supports Both Current and Future Applications · FDMA, TDMA, CDMA, TDD · AM, FM, MFSK, MPSK, MQAM, CPM, SSB, DSSS … · DES, 3 DES, AES, Me. Xe · Trunked Radio, APCO-25, GSM, Iridium, 802. 11. . · Tone Coded Squelch, CVSD, LPC, VSELP, AMBE, …. It’s just a matter of software! © 2003 General Dynamics, All rights reserved. 28 February 2021 6

Building the Cognitive Radio using SDR Technology - The SDR Radio is Available Now! · SDR drives the Cognitive Radio concept that will provide the spectral awareness technology supporting the FCC’s Spectral Use initiatives · SDR is a proven, flexible, COTS technology platform · SDR Technology is in Production and Available Now New Announcements Coming Soon © 2003 General Dynamics, All rights reserved. 28 February 2021 7

Cognitive Radio Means “Smart” and “Alert” · It knows where it is · It knows what services are available, for example, it can identify then use empty spectrum to communicate more efficiently · It knows what services interest the user, and knows how to find them · It knows the current degree of needs and future likelihood of needs of its user · Learns and recognizes usage patterns from the user · Applies “Model Based Reasoning” about user needs, local content, environmental context © 2003 General Dynamics, All rights reserved. 28 February 2021 8

How Does a Cognitive Radio Get So Smart? External Intelligence Sources Orient Establish Priority Infer on Context Hierarchy Plan Pre-process Immediate Urgent Parse Observe Receive a Message Read Buttons Outside World Normal Learn New States Save Global States Prior States Act Send a Message Set Display Generate Alternatives (Program Generation) Evaluate Alternatives Register to Current Time Decide Alternate Resources Initiate Process(es) (Isochronism Is Key) The Cognition Cycle Mitola, “Cognitive Radio for Flexible Mobile Multimedia Communications”, IEEE Mobile Multimedia Conference, 1999, pp 3 -10 © 2003 General Dynamics, All rights reserved. 28 February 2021 9

Example Spectral Awareness Etiquette That Can Be Implemented on Existing SDR / Cognitive Radio • Infrastructure Based Approaches § Possible Infrastructure Reuse - spread economic support base § Existing examples of Spectrum sharing Protocols Ø A) Trunked radio Ø B) Cellular spectrum borrowing Ø § C) Demand Assigned Multiple Access (DAMA)(demand assigned time sharing) Infrastructure Supports wide Range of Spectrum Management Policies Ø Match Requirements, Priorities, Spectral Mask of Owners © 2003 General Dynamics, All rights reserved. 28 February 2021 10

Example Spectral Awareness Etiquette Can Be Implemented on Existing SDR/Cognitive Radio (continued) Ø Cognitive Radios can adopt new etiquettes for new standards o Possible Demonstrations using existing SDRs ü Spectrum rental transactions ü Spectral Availability (Borrow) Beacon ü Local Spectrum Utilization Database Server (time, freq, code, space, power, modulation) • Distributed techniques - Possible Demonstrations § Spectral Noise temperature (Kolodzy, 2002) § RTS - CTS handshake (handshake includes local spectral activity model at each end of link, as well as BW, packet size, TX PWR for APC). Minimizes hidden node problem § Underlay, Overlay, Interweave © 2003 General Dynamics, All rights reserved. 28 February 2021 11

Example Spectral Awareness Etiquette Can Be Implemented on Existing SDR/Cognitive Radio (continued) ä Waveform Orthogonality: Time - Freq - Code - Hop/Chirp - Spatial - Usually Involves some form of CSMA sensing for high priority user Adaptive Frequency - find a frequency © 2003 General Dynamics, All rights reserved. 28 February 2021 12

SDR Finds Frequency - Time Opportunities Spectral Awareness Etiquette Deployed waveforms Existing Signals Detailed

Example Spectral Awareness Etiquette Can Be Implemented on Existing SDR/Cognitive Radio (continued) ä Waveform Orthogonality: Time - Freq - Code - Hop/Chirp - Spatial - Usually Involves some form of CSMA sensing for high priority user Adaptive Frequency - find a frequency Adaptive TDMA - find an unused time slot in between a periodic user © 2003 General Dynamics, All rights reserved. 28 February 2021 14

Opportunities for Spectral Reuse Amongst Periodic Signals © 2003 General Dynamics, All rights reserved.

Example Spectral Awareness Etiquette Can Be Implemented on Existing SDR/Cognitive Radio (continued) ä Waveform Orthogonality: Time - Freq - Code - Hop/Chirp - Spatial - Usually Involves some form of CSMA sensing for high priority user Adaptive Frequency - find a frequency Adaptive TDMA - find an unused time slot in between a periodic user Spatial - Beam steering and Null Steering © 2003 General Dynamics, All rights reserved. 28 February 2021 16

Time - Frequency - Space Each Domain has Opportunities for Spectral Reuse Transmitter forms Beam Toward Intended Recipient Receiver forms Null Toward Interference Sources R 1, R 4 T 2 T 1 Interfering Signal Placed In Null R 3, T 4 T 3 R 3 © 2003 General Dynamics, All rights reserved. 28 February 2021 17

Example Spectral Awareness Etiquette Can Be Implemented on Existing SDR/Cognitive Radio (continued) ä Waveform Orthogonality: Time - Freq - Code - Hop/Chirp - Spatial - Usually Involves some form of CSMA sensing for high priority user Adaptive Frequency - find a frequency Adaptive TDMA - find an unused time slot in between a periodic user Spatial - Beam steering and Null Steering Adaptive Bit Loading onto OFDM carriers based on SNR © 2003 General Dynamics, All rights reserved. 28 February 2021 18

OFDM Interference Avoidance QPSK Interference Spectrum Shaped QPSK @ 128 kbps 0 Power Spectrum Magnitude (d. B) -10 -20 -30 -40 -50 -60 -70 -80 Tx Spectrum -90 -100 0 0. 5 1 1. 5 Frequency (Hz) 2 Power Spectrum Magnitude (d. B) -20 -40 -60 -80 -100 -120 -140 2. 5 3 2 Survive 1. 5 1 Frequency (Hz) x 10 6 2 0. 5 Survive 0 1 Normal Transmission Number Rcv Spectrum 2. 5 x 10 6 0 -20 -40 -60 -80 -100 2. 5 3 2 Survive 1. 5 1 6 Frequency (Hz) x 10 © 2003 General Dynamics, All rights reserved. 2 0. 5 Survive 0 1 Normal Transmission Number 28 February 2021 19

Example Spectral Awareness Etiquette Can Be Implemented on Existing SDR/Cognitive Radio (continued) ä Waveform Orthogonality: Time - Freq - Code - Hop/Chirp - Spatial - Usually Involves some form of CSMA sensing for high priority user Adaptive Frequency - find a frequency Adaptive TDMA - find an unused time slot in between a periodic user Spatial - Beam steering and Null Steering Adaptive Bit Loading onto OFDM carriers based on SNR OFDM techniques where small spectral holes can be filled by one or a few carriers that fit the time - frequency hole © 2003 General Dynamics, All rights reserved. 28 February 2021 20

OFDM Carriers Selected for Use That Fall into Available Spectrum Spectral Adaptation Waveforms T

Example Spectral Awareness Etiquette Can Be Implemented on Existing SDR/Cognitive Radio (continued) ä Waveform Orthogonality: Time - Freq - Code - Hop/Chirp - Spatial - Usually Involves some form of CSMA sensing for high priority user Adaptive Frequency - find a frequency Adaptive TDMA - find an unused time slot in between a periodic user Spatial - Beam steering and Null Steering Adaptive Bit Loading onto OFDM carriers based on SNR OFDM techniques where small spectral holes can be filled by one or a few carriers that fit the time - frequency hole Interference Suppression & Multi. User Decomposition © 2003 General Dynamics, All rights reserved. 28 February 2021 22

Example Spectral Awareness Etiquette Can Be Implemented on Existing SDR/Cognitive Radio (continued) ä Waveform Orthogonality: Time - Freq - Code - Hop/Chirp - Spatial - Usually Involves some form of CSMA sensing for high priority user Adaptive Frequency - find a frequency Adaptive TDMA - find an unused time slot in between a periodic user Spatial - Beam steering and Null Steering Adaptive Bit Loading onto OFDM carriers based on SNR OFDM techniques where small spectral holes can be filled by one or a few carriers that fit the time - frequency hole Interference Suppression & Multi. User Decomposition ä Importance of Adaptive Power Control ä AD Hoc Networking (shortest hop routing w APC) © 2003 General Dynamics, All rights reserved. 28 February 2021 23

Transmitting from A -> Z : Ad. Hoc Networking Node Z Node A ©

Example Spectral Awareness Etiquette Can Be Implemented on Existing SDR/Cognitive Radio (continued) ä Waveform Orthogonality: Time - Freq - Code - Hop/Chirp - Spatial - Usually Involves some form of CSMA sensing for high priority user Adaptive Frequency - find a frequency Adaptive TDMA - find an unused time slot in between a periodic user Spatial - Beam steering and Null Steering Adaptive Bit Loading onto OFDM carriers based on SNR OFDM techniques where small spectral holes can be filled by one or a few carriers that fit the time - frequency hole Interference Suppression & Multi. User Decomposition ä Importance of Adaptive Power Control ä AD Hoc Networking (shortest hop routing w APC) © 2003 General Dynamics, All rights reserved. 28 February 2021 25

Timeline: SDR’s to have Cognitive Capabilities 2003 DARPA’s Demonstrations within 1 year 2003 2004 Commercial viability exploration & commercial analysis under existing agreements 2004 2005 2006 2007 5 years for etiquettes to be formally standardized Viability demonstrated for commercial purposes within 2 year 2005 2008 SDR Forum can initiate early work and insert into standards bodies as work matures 2006 2007 © 2003 General Dynamics, All rights reserved. 2008 28 February 2021 26

In Conclusion · SDR Products and Technology are a Reality Today · SDR Standards are Actively Being Worked today by Standards Bodies and Organizations · Cognitive Radios have the Ability to Implement Protocols and Policies Beyond Traditional Communications. · New Realms of Knowledge and Information Transfer are Achievable with Cognitive/SDR Radio as the Underlying Technology Enabler © 2003 General Dynamics, All rights reserved. 28 February 2021 27

Appendix · SCA Reference Architecture · Radio Services for Application Portability · SDR Forum Standardized Hardware Architecture · Reference Publications © 2003 General Dynamics, All rights reserved. 28 February 2021 28

SCA Reference Architecture © 2003 General Dynamics, All rights reserved. 28 February 2021 29

Radio Services For Application Portability JTR Set (Ext) Operating Environment (Int) (Ext) WF Apps (Ext) Radio Services (Int) Devices (Int) Radio Systems Applications (Ext) Middleware Services © 2003 General Dynamics, All rights reserved. 28 February 2021 30

SDR Forum* Standardized Hardware Architecture RF RF Aux I/O ANTENNA (A) Analog I/O I AIR BB / IF Real/ Complex Digital/ I/O I RF C C Aux BITS Cypher ext T Flow Contl (R) C Aux I/O I (M) C SEC I/O I LINK PROC (Black) MODEM C Key Fill C (L) C Representative Information Flow Formats BITS Plain Text Flow Contl MSG PROCESS & I/O I (R) INFOSEC Multimedia Voice Data Flow Control Video C (S) C C Routing C Network Clock/Strobe Ref, Power CONTROL (C) Common System Remote Control/ Display User Control (HMI) Aux: Special Purpose I: Information I/O for Antenna Diversity BB: Baseband Co-site Mitigation, etc. C: Control/Status Equipment Ext. Ref From Programmable Modular Communications System (PMCS) Guidance Document, 1997 *SDR Forum was established as an Industry Organization to address SDR technology on 1995 © 2003 General Dynamics, All rights reserved. 28 February 2021 31

Reference Publications ä Mitola, “Cognitive Radio for Flexible Mobile Multimedia Communications”, IEEE Mobile Multimedia Conference, 1999, pp 3 -10 ä Mitola, “Future of Signal Processing - Cognitive Radio”, Keynote, IEEE ICASSP, May 1999 ä Mitola, Maguire, “Cognitive Radio: Making SW Radios More Personal”, IEEE Personal Communications, August 1999, pp 13 -18 ä Mitola, “SDR Architecture Refinement for JTRS”, Milcom 2000, pp 214 -218 ä Mitola, “Software Radio Architecture: A Mathematical Perspective”, IEEE J on Selected Areas in Comms, April 1999, pp 514 -538 ä Margulies, Mitola, “Software Defined Radio: A Technical Challenge and a Migration Strategy”, 1998, pp 551 -556 © 2003 General Dynamics, All rights reserved. 28 February 2021 32