1. Wireless Power and Data Transfer for Sonar Array Applications By: Ricardo M. Silva Advised by: Dr. Rajeev Bansal (Univ. of Connecticut) Mr. Michael Sullivan (Electric Boat) Sponsored by: Electric Boat Lockheed Martin In cooperation with: EDONUWC

2. Problem Future sensor systems such as large passive hull mounted submarine sonar arrays may have thousands of sensors. Cables and connectors can dominate the cost of an array : Labor intensive. Labor intensive. High quality connectors are expensive. High quality connectors are expensive. Hull penetrators are expensive and bulky.

3. Problem (Continuation) Cables and connectors are a major cause of failure in large electronic systems both underwater and in the air. Repairing faulty cables and connectors is difficult: Identifying the bad cable Identifying the bad cable Removing and replacing it Removing and replacing it Labor intensive Labor intensive

4. Summary Overall Block Diagram Proposed Layout for Future Arrays RECTENNA (RECtifying anTENNA) Waveguide Setup

5. RF POWER SOURCE HULL PENETRATOR DATA RECEIVER DATA OUT TO PROCESSOR OverallBlockDiagram WAVEGUIDE MODULE 1:a RECTIFICATION & REGULATION MODULE 1:b DATA TRANSMITTER SOUND DC POWER MODULE 2MODULE 3MODULE 4

6. Proposed Layout for Future Arrays Sensors Telemetry Port Power Port Hull

7. Rectenna – The most critical part of this system - VDC + VDC Low Pass Filter D.C. Filter ½ Wave Dipole Antenna (fo= 1GHz) This filter shorts the AC component of the rectified signal to ground High efficiency Schottky diode This filter allows 1GHz through but prevents harmonics from re-radiating Operation similar to a clamper circuit

8. Waveguide Setup Cross-Section View Dielectric Medium (I.E. TEFLON ) 1GHz Waveguide Sound Sensors With embedded Rectennas Side View 1GHz Slot Antennas Top View

9. 2002 Senior-Design Outstanding Problems Efficiency of Rectenna was low (≈ 11%) Efficiency of voltage regulator was low (≈ 50%) Unable to power more than two sensors Monopole antenna position in the waveguide prevented multiple sensors from being powered Schottky diodes were operating at their power extremes causing thermal degradation over operational time Very basic telemetry system with high power requirements (250 mW) Lacked an efficient waveguide architecture that could be deployed unto a large scale sensor array

10. Project Timeline Phase-1 To be conducted during year 2003 To be conducted during year 2003 Architecture for waterborne array Architecture for waterborne array Preliminary work Preliminary work Modeling ModelingPhase-2 To be conducted during year 2004 To be conducted during year 2004 Implement design Implement design Test prototype Test prototype

11. Phase–1 Overall Architecture BROAD BAND PRESSURE SENSOR WIRELESS ARRAY CONFIGURATION COMPLIANT TUBE BAFFLES METAL/FIBERGLASS MOUNTING PLATE WAVEGUIDE SENSOR LOW BAND REFLECTION MID BAND REFLECTION HIGH BAND REFLECTION Cross-Section View Courtesy of Mr. Sullivan

12. Phase–1 Overall Architecture Courtesy of Mr. Sullivan 2 0.5 2.5 0.25, 2X2 ANGLE, Al Al PLATE 14 GLUE POLYETHYLENE VOIDED URETHANE 1/8 Al WAVEGUIDE 1/8 Al WAVEGUIDE COVER 6 3 2.5 HYDROPHONE (6 SPACED AT 6”) DIMENTIONS IN INCHES 6 ELEMENT WIRELESS ACOUSTIC ARRAY STAVE 3.5 kHz REGION ASSUMPTIONS: HIGH DENSITY POLYETHYLENE SPEED = 7970 FPS G/CM 3 = 0.69 Z = 2.33 MRayl MODULE ELECTRONICS PROBABLY SOLID FILLED EST. MAX. DIM. 2X5X1.25

13. Phase–1 Overall Architecture Courtesy of Mr. Sullivan 6 6 6 6 48 3 6 TOP VIEW SIDE VIEW. DIELECTRIC FILLED WAVEGUIDE WIRELESS ACOUSTIC ARRAY STAVE 1 GHz MONOPOLE ANTENNA (POWER XMIT.) 1 GHz SLOT ANTENNA (POWER RCV.) 2.45 GHz SLOT ANTENNA (DATA XMIT.) HYDROPHONE POLYETHYLENE DIELECTRIC RAM DIMENSIONS ARE IN INCHES ELECTRONICS HOUSING Polyethylene has been considered as a possible dielectric medium due to its low cost (1/10 of Teflon), low RF absorption at 1GHz (loss tangent =9.3E-4,.127dB/m), and good acoustic properties ( V=2.3 Km/Sec, Z = 2.33 Mray)

14. Phase–1 Overall Architecture Power Distribution - Proposed Waveguide Architectures TX Antenna SerpentineManifoldCorporate TX Antenna

15. Phase-1 Antennas Necessary to extract power from the waveguide to the rectenna Slot Antennas Widely used in radar arrays Widely used in radar arrays Easy to manufacture Easy to manufacture Stub Antennas Require insertion into the dielectric medium Require insertion into the dielectric medium Uncommon application Uncommon application Analysis required to determine the effect of the stubs in the path of the propagating energy Analysis required to determine the effect of the stubs in the path of the propagating energy

16. Phase-1 Rectenna Design The rectenna is the most crucial component in this system Previously, Silicon (Si) Schottky diodes with a Frequency-Cut-Off (fco) of 3.7 GHz were used The rectifying diodes should have a fco at least 10 x the operating frequency ( > 10 X 1 GHz) Gallium Arsenide (GaAs) diodes will be used in the future due to their higher carrier mobility By keeping the power consumption of each sensor low, it will be possible to use smaller diodes with a smaller junction capacitance (Cjo) which will have a higher fco (higher efficiency) (fco= 1 / (2 x pi x Rs x Cjo))

17. Phase-1 Rectenna Design - VDC + VDC Low Pass Filter D.C. Filter ½ Wave Dipole Antenna (fo= 1GHz) This filter shorts the AC component of the rectified signal to ground High efficiency Schottky diode This filter allows 1GHz through but prevents harmonics from re- radiating

18. Phase-1 Sensors Mr. Sullivan contacted EDO Mr. James Smith (EDO) Mr. James Smith (EDO) Mr. Wayne Richardson (EDO) Mr. Wayne Richardson (EDO) EDO is very interested in supplying a low-power Hydrophone Currently working with Electric Boat, UConn, and Lockheed Martin in identifying a suitable Hydrophone Currently working with Electric Boat, UConn, and Lockheed Martin in identifying a suitable Hydrophone

19. Phase-1 Data Telemetry EDO will be working with Lockheed Martin in providing specifications for the Hydrophones Lockheed Martin will provide the most expertise in the area of telemetry UConn has done limited research in this area since UConn is concentrating its efforts in the power delivery system

20. Phase-1 Modeling Mr. Paul Medeiros (NUWC) will be sharing his expertise in HFSS (Ansoft) and will kindly assist UConn in prototype modeling Mrs. Radhika Gurumurthy (UConn) has begun helping this team with HFSS modeling Dr. Marco Farina (MeM Research) will also be assisting UConn with 3D electromagnetic models

21. Table1 SystemSub-SystemStatusTimeframeRemarksConclusionID Overall - Architecture22 Waveguide LayoutWIPP1Aserpentine / corporate (Power)23 Waveguide DimensionsJCP1Afor 1GHz operation3" x 6 "24 Waveguide DielectricJCP1ACheaper then TeflonPolyethylene25 Waveguide Cyl Vs RectAWP1ACyl W/G Vs Rect W/G26 Rectenna27 DiodeWIPP1AGaAs28 Design of RectennaAWP1Bfilters, etc29 Slot Vs StubWIPP1Asimulation to be conducted30 Voltage RegulationAWP1BAwaiting specs from EDO/LM31 Sensor32 HydrophonesWIPP1AEDO is working with EB/LM33 Telemetry34 Data TelemetryAWP1BAwaiting LM response35 Project Progress

22. Modeling36 Slot Antenna in W/GWIPP1Alook at near field Pattern radiation37 Stub Antenna in W/GAWP1AIdentify energy pattern in TE1038 W/G SerpentineAWP1ALook at reflections39 W/G Corporate FeedAWP1ALook at power distribution40 W/G Manifold FeedAWP1BLook at power distribution41 Rectenna PSPICEJCP1ARectenna behaved like clampersee remarks42 Prototype43 Build WaveguideAWP2A44 Build RectennaAWP2A45 Test PrototypeAWP2A46 Incorporate SensorAWP2B47 Incorporate TelemetryAWP2B48 Test PrototypeAWP2B49 SystemSub-SystemStatusTimeframeRemarksConclusionID Project Progress (Cont.)