Reconfigurable Microwave Photonic Repeater for Broadband Telecom Missions: Concepts and technologies

Transcription

1 Reconfigurable Microwave Photonic Repeater for Broadband Telecom Missions: Concepts and technologies M. Aveline, M. Sotom, R. Barbaste, B. Benazet, A. Le-Kernec, J. Magnaval, P. Ginestet (TAS) O. Navasquillo, M.A. Piqueras (DAS Photonics) DOC-TAS-EN-003

2 Outline

3 Photonics on their way to satellite payloads 3

4 Mission illustration : Broadband multi-beam forward link System operators demand going towards more capacity and more flexibility 4 Telecom payloads can benefit from several advantages of microwave-photonics Expected improvements illustrated on the forward link of a multi-beam flexible payload : Frequency flexibility + routing flexibility: Any channel uplinked by a gateway can be allocated to any frequency and any beam Any colors combination is possible per gateway Compatible with : Any unbalanced N colors beam pattern Gateway deployment scenario (the first operational gateway will serve the chosen 10 highest priority beams, or 1 single gateway can feed all the beams with reduced bandwidth ) Reconfigurability all along the mission, for instance in case of gateway failure or to adapt to traffic demand changes. Gateway (*1 to *8) 80 User beams

5 Microwave photonic repeater general concept Application domain : Telecom satellite payload: 5 In particular RF intra-section : Channel demultiplexing Input section Intra section Output section Frequency conversion Routing/switching Photonic section altenative with: No need for demultiplexing before frequency conversion Optical Multi-frequency conversion : Each input translated by all the frequencies of the optical FGU One single optical conversion chain for each input access Less hardware for frequency translation Optical routing and switching : Very flexible routing : any input to any output Enables full frequency flexibility together with multi-frequency conversion

6 Microwave photonic repeater general concept Photonic alternative : Four main sections : 6 Photonic LO: generation and optical distribution of centralized (multi-frequency) Local Oscilator EOM: Microwave telecom signals transferred onto optical carriers at the Electro-Optical Mixers Distribution and switching: selection of RF LO through wavelength demultiplexing (WDM), switching, routing, amplification O/E: signals converted back into microwave domain in Opto-Electrical receivers

7 Enabling technology for photonic frequency generation Optical Frequency generation : Photonic LO : Optical double side-band modulation with carrier suppression (DSB-CS): MZ-EOM : Mach-Zender Electro Optical Modulator biased at minimum transmission point for carrier suppression Optical input = high power CW laser Modulating signal = RF input (RF LO /2) 7 OA : Optical Amplification Photonic LO concept Photonic LO optical spectrum Optical Multi-frequency generation : Combination of several Photonic LO at different wavelength: Up to 6 photonic LO s WDM for Wavelength Division Multiplexing HPOA : High Power Optical Amplification Photonic Multi-LO optical spectrum Photonic Multi-LO concept

8 Enabling technology for microwave-photonic repeater Microwave Photonic repeater : 8 RF to Photonic + frequency translation : MZ-EOM : Mach-Zender Electro Optical Modulator Optical input = Photonic Multi-frequency generation unit Modulating signal = RF input useful signals Flexibility: OA : Optical amplifier WDM: Wavelength Division Multiplexing for Wavelength and corresponding RF LO frequency selection Optical switch: between WDM and O/E, providing full flexibility (any input to any output) for LO frequency selectivity and channels routing. Optical spectrum at EOM output Conversion back to RF domain: O/E = opto-electronic receivers RF filtering: cancelling unwanted compounds RF spectrum at O/E output for CW RF input signal

9 Microwave-photonic repeater demonstrators 9 Previous projects Sat n Light demonstrator (2007) : 1. microwave photonic LO source, 2. electro-optical mixer, 3. optical cross-connect (switch Sercalo 4*4) 4. opto-microwave receivers. THALES Technodays demonstrator: 1. microwave photonic LO source, 2. Integrated KA/IF receiver 3. electro-optical mixer, 4. 4*4 MEMS based optical switching matrix 5. opto-microwave receivers. ➁ ➂ ➃ 1 4 ➀ cm Microwave-Photonic repeater with cross-connections Microwave-Photonic receiver front-end for array antenna with digital beam forming

10 Microwave-photonic repeater demonstrators On-going projects: photonic repeater breadboards 10 OMCU: Optical Multi-frequency Conversion Unit Includes photonic Multi-frequency generation (*5) Elegant BreadBoard (EBB) of the EOM slices («space like») Functional breadboard of other units (Optical multi-frequency generation unit, photo-receivers, optical amplifiers,.) Photonic Multi frequency generation unit and output optical spectrum (DAS Photonics) 2 dual EOM slices of photonic downconverter EBB

11 Microwave-photonic repeater demonstrators On-going projects: photonic repeater breadboards OWR-RFE: Optical Wideband Reconfigurable Receiver Front-End Photonic Multi-frequency generation (*6) Elegant BreadBoard (EBB) of the all the photonic units except optical switch EBB design of Photonic Multi-frequency generation for 50 EOMs : 6 redunded photonic LO, 4 redunded optical amplifiers, Combining and dividing sections EBB design of Photonic downconverter assembly: 32 photoreceivers (8 slices), 8 EOM (4 slices) 370mm 250mm 390mm 190mm

12 Photonics specificities and perspectives in Telecom Payloads Challenges for photonic introduction in telecom payloads Full microwave photonic repeater with several types of unit to qualify simultaneously, versus smaller RF photonic sub-systems for new applications to be defined Development of key units compliant with space constraints (e.g. optical switch resistant to mechanical environment, rad-hard fiber amplifier ) Potential need for performance trade-off (gain /noise figure/linearity) 12 Expected improvements/advantages : Optical fibers routing: light and easy compared to coaxial cables Photonic units developement independant from RF frequency ( same Photonic units for Ku, Ka, C, Q/V band payloads) Broadband bandwidth No sensivity to electro-magnetic interferences (EMI) Reduction of some major disturbing RF mixing products spurious thanks to photonic downconverter High scale full flexibility achievable at low mass/size with optical switching (commercial switch 80 inputs / 80 outputs : 120*80*40mm) Mass and consumption improvements estimated at this stage of development/integration from 20% to 35% depending on the type of application. (But significant potential further improvement could be done)

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