Microwave Photonics Micr crowave Ph e Photonics cs Phot otoni nics techni nique ues f s for g gene neration, on, t transm nsmissi ssion on, proc ocessi ssing o ng of microw owave ve sign gnals
Why photonics techniques Microwave Photonic Link (Radio on Fiber Link) OPTICAL FIBER OUTPUT INPUT OPTICAL PHOTO - µ W µ W SOURCE DETECTOR SIGNALS SIGNALS • Fiber can be better than coaxial cable • New functionalities
Advantage of Fiber over Coaxial Cable Fiber Coax - Size 0.25 mm 2-6 mm - Weight 0.073 g/m 30~100 g/m - Loss(dB/km) 0.4~0.8 1000~1500 - Time-Bandwidth Product >10 6 10 2
Application: Mobile Communication Networks Central Station Remote Antenna Unit Established Cell
Example of Fiber Radio system for closed-area shopping mall (Japan) Tennjinnbashisuji Shopping Mall (Osaka) Base Station Topology : Star Number of base units: 2, access units: 9 Fiber length: Approx. 2000 m/2 systems Courtesy of NTT DoCoMo
Tennjinnbashisuji Shopping Mall Base Station Optics fiber (DoCoMo) Apporox. 50m To another arcade Fixed telephone lines (NTT) Courtesy of NTT DoCoMo
RoF in the Building • World Trade Center in Japan (very high building) Antenna Topology:Star Number of base units: 2, access units: 15 Fiber length: Approx. 1200 m/2 systems Courtesy of NTT DoCoMo
Radio-on-Fiber for Closed Area Mobile Services Satellite communication ► High transmission loss of millimeter-wave - Many antenna base stations In-building - Many closed-area (no service area) ► Radio-on-fiber systems Antenna base station Antenna Household base station Shadow Central of building Office Optical fiber To other building Underground shopping mall
Broadband Wireless Access fiber Broadband fixed backbone network CARRIER FREQ.: Millimeter Waves FCC opened 70, 80 and 90GHz bands for commercial uses (2004/10) Millimeter-wave generation and processing are required
Military Applications – (1) Fiber : flexible, small and light, no EMI Communication Network Radar Systems – Phased Array Antennas
Military Applications – (2) Fiber : flexible, small and light, no EMI Communication and Radar Systems in Planes and Tanks Inter-Connection between Complex Control Systems
Atacama Large Millimeter Array (ALMA) ALMA : study the structure of the early universe and the evolution of galaxies The array consists of 64 telescopes with 12-meter dish antennas Location : high-altitude (5000 meters), extremely dry mountain site in Chile's Atacama desert for free from distortions caused by atmospheric water
Construction Sight of ALMA
Photonics in ALMA
A Simple Picture for Fiber Radio Link µ wave to µ wave to light to µ wave light baseband Requirements • Generation of microwave photonic signals • Transmission of microwave photonic signals • Detection of microwave photonic signal
Important Parameters for Fiber Radio System Fiber Radio System Digital Optical Communication Transporting and Storing Signals Transporting Bits. Bandwidth Bit rate Dynamic Range Data Recovery Spurious Free Dynamic Range Bit Error Ratio Compression Dynamic Range Eye Opening, Q Signal-to-Noise Ratio Sensitivity (for BER=10 -9 ) Noise Figure Phase Noise Jitter Intermodulation Distortion Intersymbol Interference Power Penalties Power penalties Dispersion, Chirp Dispersion, Chirp Reflections, Channel Crosstalk Reflections, Channel Crosstalk Nonlinearities Nonlinearities Output Power Error-Free Transmission High-Fidelity Transmission
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