Photonic-copper mix study for KM3NeT

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1 Photonic-copper mix study for KM3NeT Using VDSL2 in the riser Status 1 November 26 contributed by: NIKHEF electronic department Eric Heine, Mar van der Hoek, Jelle Hogenbirk, Peter Jansweijer, Lex Kruijer, Sander Mos, Henk Peek, Paul Timmer. Henk Peek et al. WP3 meeting Paris 1 November 26 Slide 1 electronic department

2 GPS rec. Clock General diagram photonic-copper mix laser λ1..n clck-sc-cal. Logics apd data apd λ1 λn 1:n λ1.. λn m branches 48V/3.5 OM 1 vertical Cable VDSL2 logic vdsl2 <1Mbps c c PMT x PMT OM 2..3 CPUs GbE Copper branch equivalent Power 1kV vdsl2 vdsl2 vdsl2 Shore station Branch cable: n x λ in one fibre, 1 x 1kV power line Main cable: m fibres, 1 x 1kV power line n = number of lines on 1kV branch (<6) m = number of branches JB Main cable branch 4/48V 1kV/4V Ref: Catania apd LINE 1 mux 3:1 logic ADM λ1.. λn λ1 3Gbps λ2.. λn Anchors LINE 2..n Henk Peek et al. WP3 meeting Paris 1 November 26 Slide 2 electronic department

3 VDSL2 Channel AN (Access Node) NT (Network Termination) Broadband Network VTU-O (VDSL-2 Transceiver Unit At ONU (Optical Network Unit)) HPF Copper Pair HPF VTU-R (VDSL-2 Transceiver Unit- Remote side) GSTN network (General Switched Telephone Network) LPF LPF Voice Terminal Data with Plain Old Telephone Service (POTS) service application Model for remote deployment with splitter (ITU G standard figure 5-7) Henk Peek et al. WP3 meeting Paris 1 November 26 Slide 3 electronic department

4 VDSL2 Spectrum Amplitude Frequency I-Q Constellations Henk Peek et al. WP3 meeting Paris 1 November 26 Slide 4 electronic department

5 VDSL2 structure Carier (min) Frequency Carier (max) Time Symbol n Symbol n+1 Symbol n+2 Symbol n+3 Symbol n+4 Symbol n+5 Symbol n+6 Symbol n+7 Amplitude Symbol n Symbol n+1 FFT Symbol n+2 Symbol n+3 Symbol n+4 Time Henk Peek et al. WP3 meeting Paris 1 November 26 Slide 5 electronic department

6 Rate/Reach Performance One twisted pair 1BaseT 1BaseT 5 Meter VDSL2: 1 Mbit/s downstream 1 Mbit/s upstream Source: Henk Peek et al. WP3 meeting Paris 1 November 26 Slide 6 electronic department

7 General properties Attenuation 24 AWG (.5 mm copper) α = 16.5 db/km/ MHz (Bingham 3.5.6) 5 M, 3 MHz α = 5 M, 5 MHz α = 57.5 db 74.1dB Bit Error Rate BER < 1-7 for any of the supported carriers (ITU - T G (VDLS2) Chapter 9.8) Note : This includes Forward Error Correction (FEC) Henk Peek et al. WP3 meeting Paris 1 November 26 Slide 7 electronic department

8 VDSL2 power levels Power 2dBm = 1 mw VDSL2 Max. transmission power level dbm 3 MHz Bandwidth/Hz = 75 db -55dBm/Hz 23.8 db 15 bits * 3 db = 45 db -126dBm/Hz -14dBm/Hz (Telecom noise floor) 47.2 db 57.5 db Cable attenuation (@ 5 M) db (BER 1-7 ) db (system margin) db (Trellis Coding) ~14 dbm/hz Frequency [MHz] Henk Peek et al. WP3 meeting Paris 1 November 26 Slide 8 electronic department

9 Custom KM3Net VDSL2 Channel DC Power DC Power AN (Acces Node) NT (Network Termination) Broadband Network VTU-O (VDSL-2 Transceiver Unit At ONU (Optical Network Unit)) LPF.25-3 MHz Copper Pair LPF.25-3 MHz VTU-R (VDSL-2 Transceiver Unit- Remote side) Reference Oscillator BPF BPF Timing Reference Rate/Reach performance 1 Mbit/s over 5 meters Henk Peek et al. WP3 meeting Paris 1 November 26 Slide 9 electronic department

10 Calibration in general Local Clock stamp => Need local time calibration Shore Station Optical Module t Shore Station t + t pd Optical Module t + 2t pd Shore Station Time Henk Peek et al. WP3 meeting Paris 1 November 26 Slide 1 electronic department

11 Calibration example B Shore Station t ta tb t + t a 15 t a t + tb ta Example, t a :15 Clock ticks, t x 21 b t + 2t a tb Optical Module A t + 2t b : 21Clock ticks t b Loopback Shore time 3 = 2 t t Loopback B Shore time 42 = 2 t t B is currently 21 a Optical Module B b = 15 = 21 A A is currently 15 a b Henk Peek et al. WP3 meeting Paris 1 November 26 Slide 11 electronic department

12 Calibration with photonic-copper mix Time calibration of the clock in each Optical Module within ~ 1ns VDSL2 Propagation delay message for the timing calibration Optical Module Fiber Propagation delay message for the timing calibration Optical Module Shore Station Fibre Base of Line Henk Peek et al. WP3 meeting Paris 1 November 26 Slide 12 electronic department

13 Calibration over optical channel Bit Clk Data 11111x K23.7 x xxxxyyyy Dx.y K D16.2 K28.5 RxRecClk Calibrate Carier Extend Calibrate fixed latency between the data and the RxRecClk => The Calibration pulse may be encoded in the 8B/1B data, for example via Carrier Extend sequence Henk Peek et al. WP3 meeting Paris 1 November 26 Slide 13 electronic department

14 Calibration over copper channel Base of Line t Optical Module t + t pd Time 5 MHz Reference 5 MHz phase Jitter < 1 ns Calibration pulse At exact known phase! (zero crossing) VDSL2 Calibration Message Time uncertainty < 2 ns VDSL2 Calibration message determines 5 MHz period (= n * 2 ns) 5 MHz phase (zero crossing) determines < 1 ns Thus propagation delay is known with < 1 ns accuracy. Henk Peek et al. WP3 meeting Paris 1 November 26 Slide 14 electronic department

15 Calibration over copper channel Base of Line Optical Module Base of Line t t + t pd t om t + t pd + t om t + 2t pd + t om Time 5 MHz Reference 4 MHz Reference Calibration pulse At exact known phase! (zero crossing) VDSL2 Calibration Message Time uncertainty < 2 ns VDSL2 Calibration Message Time uncertainty < 2 ns Need to know propagation delay from the base to the optical module. Use a second (phase locked) reference signal for calibration from Optical Module to the Base of Line. Henk Peek et al. WP3 meeting Paris 1 November 26 Slide 15 electronic department

16 Progress of photonic-copper mix Copper in the riser seems possible, it needs a single twisted pair to each Optical Module VDSL2 chipsets are in production, detailed documentation is under disclosure Attenuation of copper twisted pair needs attention A copper transmission system needs rather complex electronics EMC is a point of concern Near future: Nikhef has a disclosure agreement with Infineon and gets a set of VDSL2 evaluation boards Henk Peek et al. WP3 meeting Paris 1 November 26 Slide 16 electronic department

PERFORMANCE ANALYSIS OF WDM PONS BASED ON FP-LD USING RZ-OOK AND NRZ-OOK

PERFORMANCE ANALYSIS OF WDM PONS BASED ON FP-LD USING RZ-OOK AND NRZ-OOK Mukesh Kumar 1, Dr. Ajay Pal Singh 2 Department of Electronics and Communication Engineering, Sant Longowal Institute of Engineering