Wireless Communication Research Group (WCRG)

1. Research on Wireless Communications and Signal Processing In Two Laboratories at CISSIC: WCRG: http://www.ece.mtu.edu/ee/faculty/rezaz/wireless_lab/ WLPS: http://www.ece.mtu.edu/pages/research_labs/wlps/index.htmlDirected by Dr. Zekavat

2. Wireless Communication Research Group (WCRG) Research on: • MIMO RFID/Cognitive Radio Development; • Ad-hoc Network Capacity; • Information Fusion; • Blind Source Separation; • Optimal Beam forming in Scattering Environment; • Channel Modeling • Time-of-Arrival (TOA) and Direction-of-Arrival (DOA) Estimation Techniques; • Dynamic Channel Allocation; 14 Graduate Students are involved in WCRG

3. Activities inWireless Local Positioning System(WLPS) Directed by Seyed A. (Reza) Zekavat Michigan Technological University WLPS patent application was submitted on May 2003. Supported by NSF ITR for National Priorities

4. INTRODUCTION

5. Base An Introduction to Positioning Systems • Global Positioning Systems a. Satellites for Self Positioning, c. Mainly for Navigation, d. Command and Control via Communication, Example: Battlefield Vehicle Control e.Fails to perform in indoor and downtown areas, f. Yet expensive. • Local Positioning Systems 2. remote positioning • Command, Control, Monitoring and Tracking • Active and Passive 1. Self Positioning •Navigation (INS)

6. Motivation for WLPS To develop an active remote positioning system: Suitable: • Urban and indoor areas; • Any weather conditions; • Variety of applications (defense, Security, Law enforcement, Road Safety). • High Pd and low Pfa (Possible via Active Target Systems) It Means: • Not limited to the static base station. • Flexible coverage area. • Identify and Discriminate Mobiles; • Need limited Power

7. WLPS: An Active Remote Positioning System • Has 2 main components: Dynamic Base Station (DBS), Transponder (TRX) • DBS/TRX components can be installed in mobiles (vehicle, people, …) • Based on application each mobile might be equipped with DBS, TRX or both. • DBS discriminates mobiles (TRXes) via specific codes assigned to them. • DBS locates and tracks all mobiles (TRXes). TRX TRX

8. Positioning via WLPS TRX R, TOA DBS , DOA ID Request (IDR) Signal transmitted by DBS ID transmitted by the TRX DBS TRX Time of Arrival Duty Cycle =  / IRT ID Request Repetition Time (IRT) Time of Arrival  Distance of TRX (R) Direction of arrival (Via antenna arrays at the DBS)  Direction of TRX ( )

9. WLPS Structure • TRX: CDMA transceiver with omni-directional antenna. • DBS: Transmitter CDMA Spreading ID Request (IDR) Signal Generator Omni-directional Antenna Modulator Receiver Processor (Position Finder) Beamformer & Diversity Combiner MA RCVR and DOA finder Antenna Arrays • Hence, DBS transmits ID request signal whenever it is required (Not at all time). • The whole system: FDD/TDD/CDMA communication system.

10. PROBABILITY-OF-DETECTIONPERFORMANCE

11. Performance Evaluation – TRX Receiver DS-CDMA: Duty cycle = 0.001, 4 fold diversity Standard RCVR: Duty cycle = 0.000015, 4 fold diversity Standard RCVR: Duty cycle = 0.001, 1 fold diversity ● Further improvement is possible by selecting a larger IRT value, or a smaller value.

12. RAKE for TRX j C O M B I N E R Beamformer for the 1st path of TRX j RAKE for TRX j Beamformer for the 2nd path of TRX j Decision Rule ID Detector RAKE for TRX j Beamformer for the Lth path of TRX j RAKE for TRX j DBS Receiver: Beamforming Combined with DS-CDMA

13. Performance Evaluation – DBS RCVR The best Result with Beamforming DS-CDMA RCVR Standard RCVR (With the same BW as DS-CDMA) Standard RCVR Beam Forming ● With the same bandwidth, standard RCVR outperforms DS-CDMA RCVR. ● SDMA (beamforming) techniques highly enhances the POD performance.

14. Linear Constrained Minimum Variance (LCMV) Beam Forming • Design criteria: • Solution: In general, LCMV leads to a better removal of interference effects compared to the Conventional Beamforming.

15. Covariance Matrix Estimation for LCMV BF • Definition: • Standard estimation method: • Valid if: • However……

16. Non-Stationarity in WLPS • For WLPS: Interfering User 1 Desired User Interfering User 2 Different bits experience different interference

17. Solution: Cyclostationarity Received signal in IRT period T+1 Received signal in IRT period T Interference Signal: TRX 3 Desired Signal: TRX 1 Interference Signal: TRX 2 Same Interference Same Interference Estimated covariance matrix For nth chip of desired user Received signal at nthchip of ωth frame Number of Static User Frames

18. Probability of Miss-Detection Performance Cyclostationarity remains for 8 frames (IRT) 25 50 LCMV Beam-forming using cyclostationarity for observed signal covariance matrix highly increases the performance and the capacity.

19. DIRECTION-OF-ARRIVAL (DOA)ESTIMATION PERFORMANCE

20. DOA Estimation DOA estimation techniques developed using: • The notion of Cyclostationarity; and • Application of MUSIC algorithm.

21. Direction Combining: Approach 1 TRX2 ID signal: TRX1 ID signal:

22. Direction Combining: Approach 2 TRX2 ID signal: TRX1 ID signal:

23. DOA Mean Square Error Simulation Results

24. Simulation Results (Cont.)

25. APPLICATIONS

26. Application in Road Safety • Injuries (or die) of Hundreds of thousands of people. • Intelligent vehicle initiative was announced in 1998 by U.S. DOT. • Eight areas where intelligent systems could “improve” or “impact” safety. 1.Four kinds of collision avoidance: a. rear end, b. lane change and merge, c. road departure, and d. intersection; 2. Two kinds of enhancements: a. vision, and b. vehicle stability, 3.Two kinds of monitoring: c. driver condition and d. driver distraction. 2008 is the Deadline

27. Application in Road Safety Implementation of WLPS for Vehicle-to-Pedestrian Collision Avoidance • About one Billion people are carrying wireless mobiles, • Wireless systems offers new services everyday, • It is anticipated the number of wireless customers increases, • These people are mainly leaving in urban and highly populated areas, with high probability of accident. • WLPS protects wireless customers: Defines a new application for wireless communications. • A simple transponder in vehicles prevents Car-to-Car accident.

28. Application in Airport Security • Congress: Improvement of airport security is required [1]. • Security requires:Positioning, Monitoring, Communicating with individuals, e.g., passengers, employees, guards. • Desire: Security guards to find the position of everybody with respect to themselves at all times and all positions, inside and outside of the airport, and Whenever it is required. • Hence, System Characterization: Infrastructure-less High Probability of Detection High Coverage (Indoor, Outdoor) [1] Transportation Security Administration, “Aviation Security: Improvement still Needed in Federal Aviation Security Efforts”, GAO-04-0592T, March 30, 2004.

29. Application in Airport Security Plastic Card Boarding Pass Name : ________ Flight No. : ______ Gate No. : ________ Date: _______ Boarding Pass No: __________________ DBSantenna arrays installed on the belt TRX Name : ___________ Gate No: ______ Flight No. : _______ TRX Wristband Boarding Pass Implementation of WLPS for Indoor Areas (e.g., Airports): A Futuristic View ● Communication:The wristband can receive the updated gate, flight, etc, information. ● Monitoring: The wristband can be equipped with a heart beat sensor which is required: (a) for security guard safety, (b) to make sure the wristband is in its position.

30. Application in Airport Security Employee T. H. Flight NW 1234 Security F. E. Passenger A. W. Static Base Stations (SBS) Central Command and Control • Specific clusters of ID codes can be assigned to each group of people (employees, passengers, security guards)

31. Application in Battlefield Command and Control Precise Location Information of All Soldiers are Submitted to the Center via Satellite The Soldier with WLPS finds the position of all soldiers in its coverage area (equipped just with a simple TRX) TRX Com Node GPS/WLPS/Com (e.g., Staelleite Com) Node:WLPS: DBS/TRX • The position of the Soldier carrying WLPS (DBS and TRX) is computed by the vehicle WLPS. • This position, along with the GPS positioning leads to exact position of all soldiers. Central Command and Control

32. Applications in Law Enforcement:Multi-Agent Operation

33. Anechoic Chamber From Relay Antenna Work Station Relay Antenna Scaled Environment WLPS set (can be installed on a robot) Impact on Research and Education:Development of a Laboratory for Positioning Studiesat Michigan Tech University • This Laboratory will serve many courses: • Wireless Communications • Advanced Wireless Communications • Communication Theory • Antennas • Robotics

34. Conclusions • WLPS is an Active Target Remote Positioning System, • Consists of a Transceiver (TRX) and Dynamic Base Station (DBS), • With a variety of Civilian and Military Applications, • Much Cheaper/less complex than a GPS, • Can be used for Positioning AND Communication, • Can be a node in a MANET (Mobile Adhoc NETworks), • Can be merged with GPS (e.g., in one of the MANET nodes) to provide Global Positioning for every MANET node, • WLPS, GPS, and Communication merger leads to Central Command and Control, • An NSF award has been received (Sept. 2004) to initiate basic research (non-application oriented), • Research is Required for WLPS application-based development, • A WLPS lab has been established at the Dept. of ECE at MTU.

35. WLPS Laboratory • The TRX Hardware and Software is complete; • The DBS Transmitter Hardware and Software is Complete; • Five Ph.D. Students, three master students and one undergraduate; • Collaborating with Two Companies: Mercury Data Systems and GCI

36. Selected Recent Publications • H. Tong and S. A. Zekavat, “A Novel Wireless Local Positioning System via Asynchronous DS-CDMA and Beamforming: Implementation and Perturbation Analysis,” to appear in IEEE Transactions on Vehicular Technology, May 2007. • S. A. Zekavat, and X. Li, “User Central Wireless Systems,” Journal of Communications, vol. 1, no 1, pp. 60 -67, April 2006, Invited paper. • S. A. Zekavat, and P. T. Keong, “Beam-Pattern-Scanning Dynamic-Time Block Coding: Performance Analysis,” IEEE Transactions on Wireless Communications, vol. 5, no. 9, pp. 2334 – 2337, Sept. 2006. • H. Tong and S. A. Zekavat, “Spatially Correlated Rayleigh Channel: Generation via Virtual Channel Representation, ” IEEE Communication Letters, vol. 10, no. 05, pp. 332 – 334, May 2006. • S. A. Zekavat and C. R. Nassar, “Transmit diversity via oscillating beam pattern adaptive antennas: An evaluation using geometric-based stochastic circular-scenario channel modeling,” IEEE Transactions on Wireless Communication, Vol. 4, No. 3,pp. 1134-1141, July 2004. • S. A. Zekavat, C. R. Nassar and S. Shattil, “Merging multi-carrier CDMA and oscillating-beam smart antenna arrays: Exploiting directionality, transmit diversity and frequency diversity, ” IEEE Transactions on communications, Vol. 52, No. 1, pp. 110 – 119, Jan. 2004. • H. Tong and S. A. Zekavat, “A simple beamforming-SIMO merger in spatially correlated channel via virtual channel representation,” Proceedings IEEE Globecom 2005, St. Louis, 28 Nov. – 02 Dec., 2005. • S. A. Zekavat and X. Li, “User-Central Wireless System: Ultimate Dynamic Channel Allocation, ” Proceedings IEEE DySPAN’05, Baltimore, Nov. 8 – 11, 2005 (won graduate student travel award) • H. Tong and S. A. Zekavat, “Wireless local positioning system implementation via LCMV beamforming, ” Proceedings SPIE’05 Conference on Defense and Security, Orlando, FL, April 2005. • R. Kulkarni and S. A. Zekavat, “Smart versus blind inter-vendor spectrum sharing for MC-CDMA systems, ” Proceedings WNCG’04 Conference, Austin, TX, Oct. 2004. • S. A. Zekavat, H. Tong, and J. Tan, "A novel wireless local positioning system for airport (indoor) security, " Proceedings SPIE Conference on Defense and Security 2004, Orlando, FL, pp. 522-533, April 2004.