Transcript Photonics
Photonic technologies for aerospace applications Mauro Varasi (Finmeccanica) Roma - August 20th, 2008 Outlook Photonics: where optics meet electronics Why photonics Structural Monitoring: FBG Gyro Radar Data Links New technological frontiers Conclusions Photonics: where optic meets electronic ….. ….. in airborne platforms Airborne Radars EW systems Digital Photonics Microwave Photonics • Photonic ADC & wideband digitizer • Optical Computing • …. • Optical BFN • Waveform Generator • Filtering • Antenna remoting, remoting, Transponder • L.O. generation/distribution generation/distribution • …… Inertial Monitoring Fiber Optic Sensors Units • Smart structure Fiber Optic Link Photonics • Homeland security • Inertial sensors (gyro, gyro, acceler., acceler., ….) • Acoustic Sensor (hydrophones, hydrophones, ..) • …. Health Monitoring Signal and Data Processing Subsystems Interconnect Optoelectronic Sensors • Chemical / Biological sensors • Homeland security • …. Smart Structures Sensors • High data rate interconnections • Secure Comms • …. Data Distribution Optical interconnect • In package Chip to Chip • On board • Board to Board • ….. Quantum Optics • Cryptography • Optical computers • Secure comms • …… Secure Comms Photonics: where optic meets electronic ….. ….. in airborne platforms BRAGG GRATING FIBER OPTIC TERMINATION Data Interconnect Health Monitoring Subsystems Interconnect • computers • sensors / actuators • weapons • fly-by-light • ….. Smart Structures • Distributes fiber Sensors sensors • FBG Inertial Monitoring Units • gyroscope • ….. • Structural • Engine • Human • FLIR • wind shear • LIDAR / LOAS • Multi-Hyper Spectral • DIRCM / Designators Signal and Data Processing Airborne Radars EW systems • ESM • ECM Secure Comms • Navigation • Fire control Why photonics ? improved EM interference immunity reduce volume and weight huge digital data handling capability low losses / low dispersion wide instantaneous bandwidth real time processing high accuracy and resolution ……. Structural Monitoring: FBG Health Management System (HMS) & Health Monitoring Equipment (HME) Load monitoring Strain Sensors NDT + Stress measure Impacts Revelation Corrosion Revelation Defects Revelation Health Monitoring Equipment (HME) Fatigue Life Analysis PROGNOSIS Damage monitoring DIAGNOSIS Health Management System (HMS) HMS on-board connected to the ground support structure Structural Monitoring: FBG AOTF PRINCIPLE Fiber Optic Bragg Grating (FOBG) Bragg Law AOTF The sensorised fiber composite structure is embedded into the Variations of the grating pitch can be read (i.e. mechanical stress, thermal deformations, pressure variation, ice formation) BRAGG GRATING FIBER OPTIC TERMINATION Several sensors can be positioned on the same Cobonded J-spar with embedded FOBG senso fiber and separately A multiplex fiber system can be realized Structural Monitoring: FBG PYLON HOUSING TEST BOX Typhoon •Embedding of FOBG sensors into composite materials (carbon); System integration and ground test demonstration Centre Fuselage Stringer 10 AREA A C27J Frame 18 left side AREA B FORWARD Gyro Gyroscopes are key elements of IMU (Inertial Monitoring Units) in the navigation system of airborne platforms Optical gyroscopes have no moving parts, then: - gravitation doesn’t affect - no need for gimbal mounting - reduced sensitivity to vibrations - insensitive to EM fields Combiner cw path Ω ccw path Splitter Sagnac effect: rotation Ω induces phase shift ΔΦ between cw and ccw radiation paths ΔΦ=4π Α•Ω / λc Gyro Fiber optic gyroscope • 0,01 deg/h • Can be produced in a smaller size in principle (looses precision though) Gyro STRATEGIC NAVIGATION 1 nautical mile/hour 103 Scale Factor Stability (ppm) FIBER OPTIC TACTICAL CONSUMER FLIGHT CONTROL SMART MUNITIONS ROBOTICS TACTICAL MISSILE MIDCOURSE GUIDANCE MEMS / MEOMS AHRS TORPEDO 102 STRATEGIC CRUISE MISSILES STRATEGIC BALISTIC MISSILES 10 MECHANICAL AIR/LAND/SEA NAVIGATION SURVEYING Earth rate AUTONOMOUS SUBMARINE NAVIGATION 1 Gyro Technology Applications RING LASER 10-6 10-1 10-5 10-4 10-3 10-2 10-1 1 Bias Stability (deg/h) 10 102 103 104 105 Radar Photonic solutions in Airborne Radar systems Beam Forming networking in phased array active antennas Time delay lines Analog/Digital signal processing and distribution Fiber optic massive data transmission systems Very fast A/D converter Parallel optical computing Antenna remoting Antenna calibration Radar Digital Photonics Photonic ADC Converters Fiber Optic Massive Data Transmission System Y AX N Photonic Digital Signal Processor • 100 Gsample/s • BW >20 GHz • Resolution >8 bit • >100 Gbit/s per link Photonic a technology for advanced Radar and EW systems Frequency Generation Antenna Remoting Trasponder • Processor speed > 10 THz • 10.000 Giga Multiply Acc. Op. per sec. Filtering Optical BFN Microwave Photonics Radar Four steps towards the Photonic Antenna System RX TX Step IV: Step III: Step II: Step I: Photonic supports the RF system Photonic implements complex RF functions Photonic replaces relevant parts of the RF system Photonic assimilates the RF system Radar Analog to Digital conversion Concepts of Photonic A/D conversion basically relies on using an optical architecture to: Generate a stream of very low jitter sampling optical pulses + wavelength dispersion Modulate the height of the dispersed optical pulses by the voltage signal to be sampled through an optical modulator Split along multiple (N) parallel wavelength channels the samples Perform A/D conv. in each channel with 1/N sampling rate using std electronic A/DCs Recombine the bit stream by digital processing Radar Frequency / Waveform Generations Optoelectronic schemes and architectures for low phase noise RF oscillators at microwave frequencies (typ. 1 to 20 GHz) with high spectral purity (typ. -140 dBc/Hz @ 10 kHz offset for X band radar application) optical output dual frequency optical source ampli. filter photodiode RF splitter fiber loop(s) or µ-sphere(s) or µ-disk(s) Pump Laser E/O Modulator Optical_Out RF output Fiber Spool RF Filter RF_Out RF Sp lit te r Photo Detector Optical Path E l ec t ric a l Pa th RF A mplifier Radar Optical Beam Forming in Phased Array Antennas Optical MIR Radar Rx BFN Optical MIR EW Rx BFN Optical MIR Control Comms Rx BFN Optical MIR • Antenna architecture for the beamforming (BFN) function, supporting simultaneous multiple RF functions and allowing for a dynamic reconfiguration of array elements Analog RF and Digital control signals distributed by the same fiber network Comms Rx BFN Optical Routing Switch • Optical Interconnections Due to continually shrinking feature sizes, higher clock frequencies, and the simultaneous growth in complexity, the role of interconnect as a dominant factor in determining circuit performance is growing in importance Optical interconnects to mitigate the limitations of metal interconnects on-chip on-board board to board Optical Interconnections sub-system to sub-system “fly by light” the step beyond the “fly by wire” Optical Interconnections AFDX (Avionics Full-Duplex Switched Ethernet): Airbus implementation Through the use of twisted pair or fiber optic cables, FullDuplex Ethernet uses two separate pairs or strands for transmit and receiving data. AFDX extends standard Ethernet to provide high data integrity and deterministic timing New technological frontiers What ahead ? Multifunctional low cost integration: Hybrid Silicon Photonics Functional Polymer Integrated Circuits III-V Circuitry New devices and sensors: Photonic Band Gap Nanophotonics Plasmonics New crossings with “electrons/electronics”: Plasmonics THz New technological frontiers Multifunctional low cost integration: Hybrid Silicon Photonics Functional Polymers Integrated Circuits III-V Circuitry New technological frontiers New devices and sensors: Photonic Band Gap Plasmonics New technological frontiers Nano Photonics Conclusions • Photonic is a powerful underpinning technology in many avionic applications, enabling to advanced solutions and new capabilities • The use of COTS from the consumer communication market is accelerating the introduction of photonic solutions into aerospace platform • The most advanced photonic technologies are going to facilitate the photonic insertion into the aerospace platforms with their new multifunction integration capabilities and advanced functionalities.