Cognitive Radio Kit Framework : Experimental Platform for Dynamic Spectrum Research

1. Cognitive Radio Kit Framework : Experimental Platform for Dynamic Spectrum Research Ivan Seskar Rutgers, The State University of New Jersey www.winlab.rutgers.edu Contact: Ivan Seskar, Associate Director seskar (at) winlab (dot) rutgers (dot) edu

2. Cognitive Radio (CR) platforms • Research community already has a variety of platforms for CR research Microsoft Sora USRP2 USRP MIT Airblue U. Of Colorado RICE WARP Platform

3. Cognitive Radio platform issues • Problems with existing (experimental) platforms: do we wait for Moore’s law to catch up or we need new hardware architectures for CR? • “Analog” issues: range (frequency, power), agility, cost, scalability, future proofing • “Digital” issues: scalability, power consumption, performance vs. flexibility, cost, future proofing • Ease of “use” issues: how do we program/control these platforms? • Large scale experiments in realistic environments • Nation-wide (experimental) cognitive radio spectrum allocation • Multiple testbeds with different objectives • GENI advanced technology demonstrator of cognitive radio networks • Address New Application Needs • Spectrum sensing, vehicular networking

4. Spiral II GENI project: CR kit • Range of baseband FPGA platforms • 4 (2) configurable radio modules for phased or smart antenna applications with • Phase I: Each module allows two 25 MHz bands from 300 to 6000 MHz • Phase II: Each module allows two different 300 MHz bands from 100 to 7500 MHz • Each module supports independent full duplex operation. • 1 usec RF frequency switching time • Switched antenna diversity for both TX and RX channels.n Wide-tuning Digital Radio (WDR) block diagram

5. Why CRKIT Framework ? INNOVATIONCYCLE • Focus on Creativity, not Engineering Complexity : • Split Baseband in twodomain spaces : • Dynamic – Swappable Communication APPs • (creative problem) • Static - Open-sourced System-on-Chip • (complex engineering problem) Focus on APP Development NOT complete Radio Abstract lower level design complexities from Users • FSoC Features • Access to lower level resources thru APIs • VITA radio transport protocol for radio control • Networking capable node • Support up to four dynamic APPs • Library of Open-sourced Communication APPs • Static Framework utilization level < 15% for V5SX95, even less for newer technologies, for ex. Virtex7 . • Transparent to underlying FPGA technology. • Can be ported to future HW platforms and newer FPGA technologies. • Build Radio : • Non trivial effort • Substantial barrier to entry • Many engineering man-hours needed • Requires cross-disciplinary expertise Live system runs CRKIT= make real-time and wide-tuning radio a viable solution for large scale experiments. WDR from Radio Technology Solutions

6. CRKIT Framework Overview CRKIT HW Platform SW Platform ORBIT Integration Wide-tuning Radio Flexible Baseband Embedded HOST PHY Layer Exp. Exp. Scalability FPGA- SoC Comm. APPs Radio APIs OMF • Baseband Processor : • FPGA-based off-the-shelf board • Multitude of high-speed IOs : GigE, USB, PCIe • Control up to 4 full-duplex wideband radios • FPGA-based System-on-Chip (FSoC) implementation • Wide-tuning Radio (WDR) Module : • Wide-tuning range : 100MHz to 7.5GHz • 36MHz bandwidth • 50Msps 12-bit ADC, 200Msps 12-bit DAC • 1us switch between frequencies

7. FPGA SoC Overview • FPGA SoC components : • Ethernet Port (static) • Gigabit Ethernet rate • frame synchronization • frame generation/formatting • Packet Processor (static) • packet classification/forwarding • Control packets -> Processor Core • Data packets -> APP • Memory management for APP data • IP/VITA packet generation/formatting • Application (dynamic) • User specific designs e.g. simple QPSK/QAM, OFDM, FHSS, DSSS… • Support up to 4 APPs simultaneously • Swappable APPs, can either reside in RAM or downloadable through Ethernet port. • RF Port (static) • interfacing to DA/AD • RMAP Processor (static) • Sub-system interfacing and control • Address decoding • RF SPI Control • Processor Core (static) • 32-bit Softcore processor • bus interconnect • interfacing to 32MB DRAM • interfacing to 16MB FLASH Three distinct data flows through system: 1) APP/Processor Core to outbound ethernet port 2) Inbound ethernet port to APP 3) Inbound ethernet port to Processor Core

8. CRKIT Transport Layers APP domain (dynamic) Framework Domain : • ETH Layer – Ethernet Physical layer only, no MAC. Only Ethernet frames with Broadcast MAC or matching destination MAC addresses are forwarded to IP layer. • IP Layer (Fast Path) – • Hardware based implementation • Only a subset of IP and UDP functions. • Fast track is reserved for APP data related traffic • Data IP packets are routed to the fast track based on specific UDP port number. • IP Layer (Slow Path) – • Software based implementation • Support TCP as this is done in SW e.g. processor core. • Slow track is reserved mostly for control related traffic : CRKit hardware configuration (register map access) and RF control. • Any IP packets with UDP port number not matching the fast track UDP port number will be routed to the slow track. • Note : for Address Resolution Protocol (ARP) the IP layer is bypassed, we parse the packets based on Ethernet frame Ethertype field. • VRT Layer – • VITA Radio Transport layer, only a subset of VITA standard is supported. • VRT layer is optional, bypass this layer if not used. • VRT useful to mux multiple radio streams to a single pipe, and demux at the other end. • Standardized radio packet types: 1) Data for signal data transmission, could be digitized I/Q samples. 2) Context for control information such as set frequency, power level, bandwidth and so forth. Framework domain (static) Application Domain : • User Specific Layer - since we are in the APP domain, users have their freedom to add any new layers they may wish. • Wireless PHY – again user specific implementation.

9. Inbound Data Flow PCORE CMD FORMAT Ethertype = 0x0800 - IPv4 0x0806 - ARP If (V==1) then VITA context packet Else non-VITA packet use ethertype field for further parsing Endif; Use CMD_CNT as ACK to MEM_CTL to indicate completion of PCORE data removal from MEM. PortID Lookup Table • Forward ethernet payload if : • incoming MAC = dMAC • incoming MAC = Broadcast • Append Ethertype field (16-bit) to ethernet payload if (ethertype == IPv4 & Incoming IP == dIP & UDP = 1000-1004) then forward UDP payload to VITA Receiver else forward packet to PCORE

10. Inbound Register Map For UDP Port 1000 Traffic (VITA) Registers visible to PCORE For non-VITA traffic UDP 1001 => P0 UDP 1002 => P1 UDP 1003 => P2 UDP 1004 => P3 StreamID lookup (direct-mapped) APP Identifier

11. Outbound Data Flow If IP-Flag then IP packet processing. Lookup using PortID VRT Receiver Lookup using PortID if V-Flag then Enable VITA formatting

12. Outbound Packet Processor RMAP VITA enable flag IP enable flag VITA header IP header Lookup using PID Data/Context Lookup using PID StreamID Lookup Table MAC/IP Lookup Table

13. CRKIT Register Address Map Upper 4 MSBs : 0x0-0x1 : PCORE 0x2 : CRKIT Others : Unused 0x0 : CMN 0x1 : ETH 0x2 : PKT 0x4-0xB : APP 0xC : DAC IF 0xD : ADC IF INT SPI, LED DCM/CLOCK CE

14. CRKIT Programming Model Network CRKIT HOST CRKIT development Application development Java, C# C C GUI Algorithm Comm. APP Embedded SW System Debugging System Test CR DSA VHDL/ Verilog Mathworks Simulink IP Networking HW Configuration Host CMD Parsing DHCP/ARP Lookup Tables/ RF ETH/VITA

15. APP Development Flow APP Specification PCORE boots CRKIT Flow Design dynamic APP Execute CRKIT Embedded SW MATLAB Simulink Flow APP Validation • Get IP address using DHCP • Discover HOST • Configure CRKIT hardware • Parse HOST commands CRKIT Embedded SW Compile APP Networking Link APP to Framework HW Config. Host CMD Parsing initial config. Compile Framework Xilinx ISE Flow RF Control Lookup Table Configuration Generate FPGA bit file dynamic Config. (ETH/VITA) Download to Hardware

16. Innovation Cycle Feedback idea Algorithms/ Models Build Radio Live Experiments Creative Processes Engineering Processes

17. APP SimulinkEnvironment Data Verification IO Validation Channel Model BMU MON APP RF LPBK I/Q data .txt files BMU DRV I/Q ETH .txt files Register Read/Write PCORE DRIVER Send X data packets CMD .txt file

18. APP SimulinkTestbench

19. Rendezvous APPs

20. QPSK Transmitter

21. QPSK Receiver

22. Rendezvous APP – FPGA Utilization

23. ORBIT Integration Actual SB6 with two CRKITs ORBIT SB6 OPEN TO ORBIT COMMUNITY !

24. Conclusion • CRKIT = Advanced Radio System enabling experimental research in CR and DSA techniques • Powerful combination of Wideband Radio and Flexible Baseband Processing • FSoC Static and Dynamic domain spaces • APP development for Creativity and Productivity => MATLAB/Simulink • Framework development for Engineering Complexity=> Traditional Hardware design flow • ORBIT Integration => User Friendliness Experience + Experimentation Scalability

25. Future Work • Extend APP library : OFDM-based waveform APP • Upgrade Static framework to support live loadable APPs from Network : • Clock Management • Run-time Reconfiguration • Port Linux to PCORE • Integrate CRKIT fully into ORBIT Management Framework (OMF) • Extreme Digital Radio (XDR) : 800MHz Bandwidth • Upgrade baseband processor board to newer and higher performance FPGA technologies