Ultrafast Coherent Optical Signal Processing Coherent Optical Signal Processing using Stabilized Optical Frequency Combs from Mode- ... Sensing, Detecting and

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<ul><li><p>Ultrafast Coherent Optical Signal </p><p>Processing using Stabilized Optical </p><p>Frequency Combs from Mode-</p><p>locked Diode Lasers Peter J. Delfyett </p><p>CREOL, The College of Optics and Photonics, University of Central Florida, Orlando, Florida 32816-2700 </p><p>delfyett@creol.ucf.edu </p><p>University of California </p><p>Santa Barbara, CA </p><p>December 5, 2012 </p></li><li><p>2 </p><p>Outline </p><p> Motivation Background </p><p> Key Technologies </p><p> Stabilized Optical Frequency Combs </p><p> Arcsine Phase &amp; Linear Intensity Modulators w/ Comb Filter </p><p> Direct Phase Detection (w/o external local oscillator) w/ Comb Filter </p><p> Applications </p><p> Arbitrary Waveform Measurements </p><p> Arbitrary Waveform Generation </p><p> Pattern Recognition using Matched Filtering Techniques </p><p> Summary and Conclusions </p></li><li><p>3 </p><p>Motivation </p><p>Why Diode Based Fiber Lasers? Diode lasers are small (100s microns), electrically efficient </p><p>(&gt;70%), wavelength agile (300 nm to &gt;10 microns via </p><p>bandgap engineering). </p><p> Robust, no moving / mechanical parts </p><p> Broad bandwidth potential for large tuning bandwidth. </p><p> Operates over very broad temperature ranges. </p><p> Cost effective, direct electrically (battery) pumped. </p><p> Can engineer the cavity Q to be &gt;&gt; than conventional cavities </p><p> Potential for photonic integrated circuits, e.g., electronics, </p><p>lasers, modulators &amp; detectors full functioning </p><p>optoelectronic systems on a chip </p><p> computing &amp; signal processing at the speed of light! </p></li><li><p>4 </p><p>Ultrawideband Communications </p><p>Synthetic Aperture Imaging Sensing, Detecting and Response </p><p>Applications Enabled By Optical Frequency Combs </p><p>Advanced Waveform Generation/Measurement </p></li><li><p>5 </p><p>Time Interleaved Pulse Trains Time Overlaid Pulse Trains </p><p> Interleaved Supermode Spectra Overlaid Supermode Spectra </p><p> P</p><p>ow</p><p>er </p><p>Time </p><p>Po</p><p>wer </p><p>Optical Frequency </p><p>Am</p><p>pli</p><p>tud</p><p>e </p><p>Time </p><p>Po</p><p>wer </p><p>Po</p><p>wer </p><p>Time </p><p> Optical Frequency </p><p>Am</p><p>pli</p><p>tud</p><p>e </p><p>Po</p><p>wer Time </p><p>ei </p><p>ei2 </p><p>E(-) </p><p>E(-2) </p><p>E() </p><p>2 </p><p>Po</p><p>we</p><p>r </p><p>eit </p><p>eit2t </p><p>fML </p><p>c/L </p><p>TC=L/c </p><p>c/L </p><p>fML </p><p>T= 1/fML </p><p>A1=1 </p><p>A2=1 </p><p>A3=0.5 </p><p>Harmonic Modelocked Lasers Schematic Representations </p></li><li><p>6 </p><p>0 200 400 600 800 1000 12000</p><p>50</p><p>100</p><p>150</p><p>200</p><p>250Intensity of Optical Pulse Train</p><p>Time</p><p>Inte</p><p>nsity</p><p>0 100 200 300 400 500 600 700 800 900 1000</p><p>195</p><p>200</p><p>205</p><p>210</p><p>215</p><p>220</p><p>225</p><p>230</p><p>235</p><p>Intensity of Optical Pulse Train</p><p>Time</p><p>Inte</p><p>nsity</p><p>210 220 230 240 250 260 270 280 290 300 3100</p><p>0.1</p><p>0.2</p><p>0.3</p><p>0.4</p><p>0.5</p><p>0.6</p><p>0.7</p><p>0.8</p><p>0.9</p><p>1</p><p>Optical Spectrum of Pulse Train</p><p>Frequency</p><p>Watt</p><p>s/H</p><p>z</p><p>20 40 60 80 100 120 140</p><p>-80</p><p>-60</p><p>-40</p><p>-20</p><p>0</p><p>20</p><p>RF Power Spectrum of Pulse Train</p><p>Frequency</p><p>dB</p><p>/Hz</p><p>Supermode Noise Spurs </p><p>(a) </p><p>(c) </p><p>(b) </p><p>(d) </p><p>Optical Pulse Train Intensity Optical Pulse Train Intensity </p><p>Optical Spectrum of Pulse Train RF Power Spectrum of Pulse Train </p></li><li><p>7 </p><p>Low Noise Modelocked Diode Lasers </p><p>Via </p><p>Stabilization of the Frequency Comb </p></li><li><p>8 </p><p>Fundamentally Modelocked Lasers </p><p>Time </p><p>Optical Frequency </p><p>fmod=c/L </p><p> =10 GHz </p><p>L </p><p>c/L </p><p>T=100 ps </p><p>~ </p><p>Po</p><p>wer </p><p>Po</p><p>wer </p><p>Log Frequency </p><p>RF Power Spectrum </p><p>Corner frequency moves to </p><p>large offset frequencies w/ short cavities </p><p>1 pulse in the cavity </p><p>Corner </p><p>Frequency </p><p>SOA </p><p>System Noise Floor </p><p>RF Power Spectrum </p><p>Frequency </p></li><li><p>9 </p><p>Harmonically Modelocked Lasers </p><p>Time </p><p>Optical Frequency </p><p>fmod=Nc/L </p><p> =10 GHz </p><p>L </p><p>c/L </p><p>T=100 ps </p><p>~ </p><p>SOA </p><p>Po</p><p>wer </p><p>Po</p><p>wer </p><p>Log Frequency </p><p>RF Power Spectrum </p><p>Supermodes </p><p>System Noise Floor </p><p>Example: Ring Laser </p><p>Mode Spacing=10 MHz </p><p>fmod= 10 GHz </p><p>N=1000 </p><p>N pulses in the cavity </p><p>N Independent longitudinal </p><p> mode groups </p><p>Coupled Modes </p><p>Corner </p><p>Frequency </p><p>10GHz RF Power Spectrum </p></li><li><p>10 </p><p>Harmonic Modelocking &amp; Supermode </p><p>Suppression </p><p>Fmod=nc/L </p><p> = 10GHz </p><p>L </p><p>T=100 psec </p><p>~ </p><p>Time </p><p>Optical Frequency </p><p>10GHz </p><p>T=100 psec </p><p> P</p><p>ow</p><p>er </p><p>Po</p><p>wer </p><p>Time </p><p>Optical Frequency </p><p>10GHz </p><p>T=100 psec </p><p>Po</p><p>wer </p><p>Po</p><p>wer </p><p>SOA </p><p>=10GHz </p><p>Fmod=nc/L </p><p> =10GHz </p><p>L </p><p>~ </p><p>Supermode </p><p>Suppression Filter </p><p>SOA </p></li><li><p>11 </p><p>Ii</p><p>T</p><p>1 R exp i d i</p><p>64</p><p>0.0 I2i</p><p>T2</p><p>1 R2 exp i di </p><p>8</p><p>0.0</p><p>0</p><p>0.2</p><p>0.4</p><p>0.6</p><p>0.8</p><p>1</p><p>1.2</p><p>0</p><p>0.2</p><p>0.4</p><p>0.6</p><p>0.8</p><p>1</p><p>1.2</p><p>Frequency </p><p>Tran</p><p>smis</p><p>sio</p><p>n </p><p>Frequency </p><p>Tran</p><p>smis</p><p>sio</p><p>n </p><p>(a) </p><p>(b) </p><p>Nested Optical Cavities </p><p>R1=R2=90%; T1=T2 =10%; FSR2 / FSR1 =8 </p><p>Cavity Product Identical to R=99%; T=1% </p></li><li><p>12 </p><p>Harmonically Mode-locked Lasers &amp; </p><p>Supermode Suppression </p><p>Modulation rate </p><p>The etalon free spectral range must match the mode-locking rate. </p><p>Laser cavity modes must coincide with etalon transmission peaks. </p><p>Mode spacing </p><p>Etalon transmission </p><p>Laser cavity </p><p>10.24 GHz </p><p> SOA </p><p>IM </p><p>PC I </p><p>PC </p><p>DCF </p><p>DC </p><p>etalon </p><p>PC </p><p>PC </p><p>DCF </p><p>FL </p><p>SOA: semiconductor optical amplifier </p><p>PC: polarization controller </p><p>IM: intensity modulator </p><p>I: isolator </p><p>DCF: dispersion compensating fiber </p><p>FL: fiber launcher </p><p>FL </p></li><li><p>13 </p><p>Setup </p><p>SOA </p><p>VOD OPS </p><p>IM </p><p>I I </p><p>PC PC </p><p>PC </p><p>Output </p><p>DC </p><p>PC </p><p>Free Space </p><p> Optics FPE </p><p>PM </p><p>Cir </p><p>PBS </p><p>PID </p><p>O PS </p><p>PC </p><p>PC </p><p>PD </p><p>640 MHz </p><p>Laser Cavity </p><p>PDH Loop </p><p>I: isolator </p><p>SOA: semiconductor optical </p><p>amplifier </p><p>OPS: Optical phase shifter </p><p>PD: photodetector </p><p>PC: polarization controller </p><p>IM: intensity modulator </p><p>PBS: polarization beam splitter </p><p>FPE: Fabry-Perot etalon </p><p>PID: PID controller </p><p>PM: phase modulator </p><p>Cir : optical circulator </p><p>OPS: Optical Phase Shifter </p><p>VOD: Variable Optical Delay </p><p>DCF: Dispersion Comp. Fiber </p><p>PDH: Pound Drever Hall </p><p>Ultra-low noise osc. </p><p> at 10.287GHz </p></li><li><p>14 </p><p>Laser is constructed on a optical breadboard and thermally and </p><p>acoustically isolated with foam insulation. </p><p>Actively MLL with intracavity 1000 Finesse </p><p>etalon </p></li><li><p>15 </p><p>The pulses are compressed to 1.1 ps autocorrelation FWHM by using a </p><p>dual grating compressor. </p><p> Sampling scope and autocorrelation traces </p><p>Actively MLL with intracavity 1000 Finesse </p><p>etalon </p></li><li><p>16 </p><p>The 10 dB spectral width of the optical spectrum is ~8.3nm. </p><p>The comb line has a ~50dB signal-to-noise ratio </p><p> Optical spectrum </p><p>Actively MLL with intracavity 1000 Finesse </p><p>etalon </p><p>High Resolution Comb Line </p></li><li><p>17 </p><p> Timing jitter and amplitude noise: </p><p>Actively MLL with intracavity 1000 Finesse </p><p>etalon </p><p> Integrated timing jitter (1 Hz 100 MHz) is ~3fs </p><p>and up to Nyquist it is 14fs. </p><p> Integrated amplitude noise (1 Hz 100 </p><p>MHz) is 230ppm. </p><p>Note the overall dynamic range of the measurement 1016 ) </p></li><li><p>18 </p><p>The linewidth of the laser with the 1000 Finesse etalon was measured as ~ 500 Hz </p><p>(Note the relative ratio of the carrier frequency to the linewidth ~ 1012) Stability of 150 kHz over 30 sec </p><p>(NB: Measurements are limited by the CW laser linewidth &amp; stability) </p><p>MLL </p><p>CW laser </p><p>PC RFSA </p><p>OSA </p><p>-20 -10 0 10 20-70</p><p>-60</p><p>-50</p><p>-40</p><p>-30</p><p>-20</p><p>-10</p><p>0</p><p>Am</p><p>plit</p><p>ude</p><p> (d</p><p>Bm</p><p>)</p><p>Frequency (GHz)</p><p>High Resolution Spectrum Analyzer </p><p>CW laser</p><p>Stabilized Frequency Comb lines</p><p> Optical linewidth/stability measurement. </p><p>Actively MLL with intracavity 1000 Finesse </p><p>etalon </p><p>Stability </p></li><li><p>19 </p><p>Low Noise Modelocked Diode Lasers </p><p>The Effect of Intracavity Power </p></li><li><p>20 </p><p>SCOW Amplifier SCOWA Slab-Coupled Optical Waveguide Amplifier </p><p>J. J. Plant, et. al. IEEE Phot. Tech. Lett., v. 17, p.735 </p><p>(2005) </p><p>W. Loh, et. al. IEEE J. Quant. Electron., v. 47, p. 66 </p><p>(2011) </p><p>0 5 10 15 20 25 300</p><p>3</p><p>6</p><p>9</p><p>12</p><p>15</p><p>Pout</p><p> (dBm)</p><p>Ga</p><p>in (</p><p>dB</p><p>)</p><p>1 A</p><p>2 A</p><p>3 A</p><p>4 A</p></li><li><p>21 </p><p>Etalon stabilized HMLL Experimental setup </p><p>CIR: Circulator DBM: Double Balanced Mixer FPE: Fabry-Perot Etalon ISO: Isolator LPF: Low-Pass Filter OC: Output Coupler (Variable) PC: Polarization controller PD: Photodetector PID: Proportional-Integral-Differential Controller PM: Phase Modulator PS: Phase Shifter PZT: Piezoelectric Transducer (Fiber Stretcher) SOA: Semiconductor Optical Amplifier (SCOWA) VOD: Variable Optical Delay </p><p>Pound-Drever-Hall Loop </p><p>Optical Path </p><p>Electrical Path </p><p>SCOWA </p><p> IM </p><p>PC </p><p>PC </p><p>ISO ISO </p><p>FPE (FSR = 10.287 GHz) </p><p>OC </p><p> PS </p><p> PID </p><p>DBM </p><p>PD </p><p>CIR </p><p>LPF </p><p> PM </p><p>PC </p><p>PC PC </p><p>10.287 GHz </p><p>500 MHz </p><p>PC </p><p>Laser Output </p><p>Ultra-low </p><p>noise oscillator </p><p> Long fiber cavity provides narrow resonances </p><p> Fabry-Prot Etalon provides wide mode spacing </p><p> Pound-Drever-Hall loop locks both cavities </p><p> An ultra-low noise oscillator is used to drive the laser </p><p> VOD PZT </p><p>I. Ozdur, et. al., PTL, v. 22, pp. 431-433 (2010) </p><p>F. Quinlan, et. al., Opt. Express 14, 5346-5355 (2006) </p><p>PBS </p></li><li><p>22 </p><p>-80</p><p>-70</p><p>-60</p><p>-50</p><p>-40</p><p>-30</p><p>-20</p><p>Pow</p><p>er </p><p>(dB</p><p>m)</p><p>Frequency (100 MHz/div)</p><p>Span: 1 GHz</p><p>Res. BW: 1 MHz</p><p>~60 dB </p><p>High-Resolution Optical Spectrum Optical Spectrum </p><p>1544 1546 1548 1550</p><p>-70</p><p>-60</p><p>-50</p><p>-40</p><p>-30</p><p>-20</p><p>-10</p><p>Pow</p><p>er </p><p>(dB</p><p>m)</p><p>Wavelength (nm)</p><p>~60 dB </p><p>10.24 10.26 10.28 10.30 10.32-110</p><p>-100</p><p>-90</p><p>-80</p><p>-70</p><p>-60</p><p>-50</p><p>-40</p><p>-30</p><p>-20</p><p>-10</p><p>0</p><p>Rela</p><p>tive P</p><p>ow</p><p>er </p><p>(dB</p><p>)</p><p>Frequency (GHz)</p><p>Span: 100 MHz</p><p>Res. BW: 3 kHz</p><p>Radio-Frequency Spectrum </p><p>1 10 100 1k 10k 100k 1M 10M 100M</p><p>-170</p><p>-160</p><p>-150</p><p>-140</p><p>-130</p><p>-120</p><p>-110</p><p>-100</p><p>-90</p><p>-80</p><p>-70 Residual Phase Noise</p><p> Noise Floor</p><p> Poseidon Oscillator Absolute Noise</p><p>L(f</p><p>) (d</p><p>Bc/H</p><p>z)</p><p>Frequency Offset (Hz)</p><p>0.0</p><p>0.5</p><p>1.0</p><p>1.5</p><p>2.0</p><p>2.5</p><p>3.0</p><p> Inte</p><p>gra</p><p>ted T</p><p>imin</p><p>g J</p><p>itte</p><p>r (f</p><p>s)</p><p>Single sideband phase noise spectrum </p><p>Etalon-stabilized </p><p>laser (10.287 GHz) </p><p>Etalon-stabilized </p><p>laser (10.285 GHz) </p><p>Real-time Spectrum Analyzer </p><p>Real-time spectrogram </p><p>Tim</p><p>e (3</p><p>5 s</p><p>) </p><p>4 2 0 -2 -4 </p><p>Frequency Offset (MHz) </p><p>Optical Frequency Stability Measurement </p><p>Etalon-based Ultralow-noise Frequency </p><p>Comb Source </p></li><li><p>23 </p><p>Oscillator characterization </p><p>-40 -30 -20 -10 0 10 20 30 40</p><p>0.0</p><p>0.5</p><p>1.0</p><p> Compressed AC</p><p> Transform Limited AC</p><p>AC</p><p> Tra</p><p>ce (</p><p>a.u</p><p>.)</p><p>Delay (ps)</p><p>p = 930 fs</p><p>10.24 10.26 10.28 10.30 10.32</p><p>-100</p><p>-80</p><p>-60</p><p>-40</p><p>-20</p><p>0</p><p>Re</p><p>lative</p><p> Po</p><p>we</p><p>r (d</p><p>B)</p><p>Frequency (GHz)</p><p>Span: 100 MHz</p><p>Res. BW: 3 kHz</p><p> Pulses are compressible to close to the transform limit </p><p> Photodetected RF tone has &gt;90 dB dynamic range </p><p>Intensity Autocorrelation RF Power Spectrum </p></li><li><p>24 </p><p>Amplification Output power and spectral characteristics </p><p>-60</p><p>-40</p><p>-20</p><p>-60</p><p>-40</p><p>-20</p><p>1552 1554 1556 1558 1560 1562 1564</p><p>-60</p><p>-40</p><p>-20 I=4A, P</p><p>out=320 mW</p><p> I=4A, Pout</p><p>=214 mW</p><p> Directly from MLL</p><p>Op</p><p>tica</p><p>l P</p><p>ow</p><p>er </p><p>(dB</p><p>m)</p><p>Wavelength (nm)</p></li><li><p>25 </p><p>1 10 100 1k 10k 100k 1M 10M 100M</p><p>-170</p><p>-160</p><p>-150</p><p>-140</p><p>-130</p><p>-120</p><p>-110</p><p>-100</p><p>-90</p><p>-80</p><p>-70(iv)</p><p>(iii)</p><p>(ii) (i) All-anomalous Cav.</p><p> (ii) Disp. Comp. Cav.</p><p> (iii) All-anomalous and Covega</p><p> (iv) Poseidon Oscillator</p><p> Noise Floor</p><p>L(f</p><p>) (d</p><p>Bc/H</p><p>z)</p><p>Frequency Offset (Hz)</p><p>(i)</p><p>0</p><p>2</p><p>4</p><p>6</p><p>8</p><p>10</p><p> In</p><p>teg</p><p>rate</p><p>d J</p><p>itte</p><p>r (f</p><p>s)</p><p>and SCOWA </p><p>Timing Jitter SSB Phase Noise Comparison </p></li><li><p>26 </p><p>Outline </p><p> Motivation Background </p><p> Key Technologies </p><p> Stabilized Optical Frequency Combs </p><p> Arcsine Phase &amp; Linear Intensity Modulators w/ Comb Filter </p><p> Direct Phase Detection (w/o external local oscillator) w/ Comb Filter </p><p> Applications </p><p> Arbitrary Waveform Measurements </p><p> Arbitrary Waveform Generation </p><p> Pattern Recognition using Matched Filtering Techniques </p><p> High Precision Laser Radar w/ Unambiguous Ranging &amp; </p><p>Velocimetry </p><p> Summary and Conclusions </p></li><li><p>27 </p><p>General Ideas for OFC Modulation </p><p>Desirable Modulator Qualities for real time OFC applications: </p><p>Current methods of modulating light intensity: </p><p> Direct modulation of diode driving current Frequency chirp </p><p> External modulation: </p><p> Electro-optic modulators (EOM) Nonlinear modulation transfer function </p><p>and Relatively high V </p><p> Electro-absorption modulators (EAM) Poor optical power handling, </p><p>High insertion loss and Sensitive to temperature and wavelength </p><p>Proposed concept for OFC modulation: </p><p> Injection locking a resonant cavity w/ gain (VCSEL) arcsine phase modulation NB: Linear intensity modulator in an interferometric configuration </p><p>- Linear modulation transfer function </p><p>- Large modulation bandwidth </p><p>- Low Insertion Loss (negative..?) </p><p>- Low V </p><p> - Good power handling capability </p><p> - Comb filtering, tunable, arrays </p></li><li><p>28 </p><p>Injection-Locked Resonant Cavity as an Arcsine Phase </p><p>Modulator </p><p>1 </p><p>0 </p><p>Master laser </p><p>1 </p><p>Slave laser 0 </p><p>Adlers equation*: </p><p> = 1</p><p> = 2: locking range </p><p>*A. E. Siegman, Lasers, 1986 </p><p> = </p><p>Locking range </p><p>0 </p><p>1 </p></li><li><p>29 </p><p>V </p><p>f(t) ~ </p><p>/2 </p><p>Iin </p><p>V </p><p>T(V) </p><p>))((sin 1 tf</p><p>I0 ,1 )2</p><p>)(1(</p><p>tfII inout</p><p>Resonant cavity linear modulator Phase response Stable locking range </p><p> Calculate SFDR </p><p>f(t) ~ </p><p>Iin </p><p>T(V) </p><p>)2</p><p>)cos(1(</p><p> inout II</p><p>Electro-optic Mach-Zehnder modulator </p><p> VtV /)(0 </p><p>Resonant Cavity Interferometric Modulator Comparison to a Conventional MZ Modulator </p><p>outI</p><p>outI</p></li><li><p>30 </p><p>Filtering &amp; </p><p>Modulation </p><p>Optical Spectrum RF Spectrum </p><p>f1 </p><p>VCSEL </p><p>Bias T </p><p>AC Modulation; f1, </p><p>DC current= I1 </p><p>Phase Modulation &amp; Filtering -Channel selection concept </p><p>I() </p><p> f </p><p>P(f) </p><p>Ch. 1 </p><p>DC=I1 </p><p>Ch. 2 </p><p>DC=I2 </p><p>Ch. 1 </p><p>Ch. N </p><p>Ch. 2 </p><p>Comb Modulated Output </p><p> 0 = + f1 </p></li><li><p>31 </p><p>Filtering &amp; </p><p>Modulation </p><p>VCSEL </p><p>Bias T </p><p>AC Modulation; f2 </p><p>DC current= I2 </p><p>Phase Modulation &amp; Filtering -Channel selection concept </p><p>Ch. 1 </p><p>Ch. N </p><p>Ch. 2 </p><p>Comb Modulated Output </p><p>RF spectrum </p><p>f2 f </p><p>P(f) = + f2 I() </p><p> Ch. 1 DC=I1 </p><p>Ch. 2 </p><p>DC=I2 </p><p> 0 </p><p>Optical Spectrum 8.6 8.7 8.8 8.9 9.0</p><p>193.405</p><p>193.410</p><p>193.415</p><p>193.420</p><p>193.425</p><p>193.430 Measurement</p><p> Linear fit</p><p>Fre</p><p>quency (</p><p>TH</p><p>z)</p><p>DC Driving Current (mA)</p><p>Slope ~ 50 GHz/mA </p><p>Frequency vs. Current </p></li><li><p>32 </p><p>Linear Modulator Experimental Results </p><p>0 1 2 3 4 5 6</p><p>-80</p><p>-75</p><p>-70</p><p>-65</p><p>-60</p><p>-55</p><p>-50</p><p>Po</p><p>we</p><p>r (d</p><p>Bm</p><p>)</p><p>Frequency (GHz)</p><p>10 dB</p><p>00 00 00 000 00 00 00 000 </p><p>0 </p><p>0 </p><p>0 </p><p>0 </p><p>0</p><p>0 </p><p>0 </p><p>0 </p><p>0 </p><p>0 </p><p>0 Measurement</p><p> Fit </p><p> Sta</p><p>tic p</p><p>hase (</p><p>rad</p><p>ian</p><p>)</p><p>DC Current Deviation (mA)</p><p>1 GHz </p><p>1.0001 GHz </p><p>CW </p><p>laser </p><p>PID </p><p>RFSA </p><p>VCSEL </p><p>High-res </p><p>OSA </p><p>+ </p><p>Bias </p><p>Tee </p><p>EDFA </p><p>IDC RF </p><p>VOA PC </p><p>50/50 Iso </p><p>PD </p><p>PD </p><p>90/10 </p><p>PZT </p><p>VCSEL: vertical cavity surface emitting laser </p><p>Iso: isolator </p><p>VOA: variable optical attenuator </p><p>PC: polarization controller </p><p>PZT: piezoelectric transducer </p><p>PD: photo detector </p><p>PID: proportional-integrated-differential controller </p><p>CIR: circulator </p><p>OSA: optical spectrum analyzer </p><p>RFSA: RF spectrum analyzer </p><p>CIR </p><p>Spur free dynamic range of ~130 dB.Hz2/3 </p><p>Very low V of ~ 2.6 mV </p><p>Multi-gigahertz bandwidth (~ 5 GHz) </p><p>Possible gain </p><p>PC </p><p>-80 -70 -60 -50 -40 -30 -20</p><p>-160</p><p>-140</p><p>-120</p><p>-100</p><p>-80</p><p>-60</p><p>-40</p><p>-20</p><p>0</p><p> Fundamental</p><p> IM3</p><p>Fu</p><p>nd</p><p>am</p><p>enta</p><p>l &amp;</p><p> in</p><p>term</p><p>odu</p><p>latio</p><p>n</p><p> pow</p><p>er </p><p>(dB</p><p>m)</p><p>RF Input (dBm)</p><p>Noise floor </p><p>SFDR = 130 </p><p>dB.Hz2/3 </p></li><li><p>33 </p><p>Outline </p><p> Motivation Background </p><p> Key Technologies </p><p> Stabilized Optical Frequency Combs </p><p> Arcsine Phase &amp; Linear Intensity Modulators w/ Comb Filter </p><p> Direct Phase Detection (w/o external local oscillator) w/ Comb Filter </p><p> Applications </p><p> Arbitrary Waveform Measurements </p><p> Arbitrary Waveform Generation </p><p> Pattern Recognition using Matched Filtering Techniques </p><p> High Precision Laser Radar w/ Unambiguous Ranging &amp; </p><p>Velocimetry </p><p> Summary and Conclusions </p></li><li><p>34 </p><p>Direct demodulation of phase </p><p>modulated signals </p><p> Operating principle: Detecting light-induced changes in the </p><p>forward voltage of an optically injection locked VC

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