Quantum Encryption System - Synchronization presentation Midterm Project name: Synchronization for Quantum Encryption System Project supervisor : Yossi Hipsh. Project performed by : Omer Mor Oded Belfer.

Quantum Encryption System - Synchronization Project Goal The Synchronization system is an integral part of a quantum encryption system. The system will allow transferring messages in a safe way that a third unauthorized person would not be able to decipher. The Synchronization system is needed to control the detector so it would be able to identify a single photon in an optic cable at a given time.

Quantum Encryption System - Synchronization System requirements Locate and place a single photon with 1nSec accuracy resolution, in a 3nSec window. The system should be a “stand alone” system and not depended on other components of the encryption system. For that we will need to simulate the other systems. The system should be capable to work with very fast pulses. The system will receive an Optic Sync signal and transfer it to a delayed electric signal, according to the photon arrival.

Quantum Encryption System - Synchronization General Block scheme

Quantum Encryption System - Synchronization Synchronization system – General Block scheme 5V Surface 3.3V Surface

Quantum Encryption System - Synchronization General Block scheme – 5V Surface Optic Detector Board Pulse stretcher Splitter TTL D.D.L TTL Ref – Test point ComputerD.D.L TTL *components marked in yellow are detailed latter. FPGA Splitter TTL Ref – T.P To 3.3V Sync Photon 24nSec ≤ τ ≤ 0.5μSecPulse width 15-35nSec Optic sync From transmitter 5V Surface Synchronization board.

Quantum Encryption System - Synchronization General Block scheme – 3.3V Surface Mono Stable TTL To ECL Splitter ECL D.D.L ECL *components marked in yellow are detailed latter. Balanced to Unbalanced Splitter ECL Ref – Test point To Receiver 30pSec ≤ τ ≤ 10nSec Pulse width 3nSec From 5V TTL splitter 3.3V Surface Synchronization board. Splitter ECL Balanced to Unbalanced Ref – Test point

Quantum Encryption System - Synchronization Special components – FPGA Input Output FPGA Sync END Computer Sync START D.D.L TTL D.D.L ECL D.D.L TTL “Photon” – from splitter #1 “Sync” – from splitter #2 ADD1 Enable ADD2 Enable STR1 Valid photon 1 STR2 Valid photon 2 * ’Valid photon’ will be used only if STR is not available.

Quantum Encryption System - Synchronization Special components – Optic Detector Board Regulator 9V Input Optic Detector Transformator Optic Sync. Input From transmitter Pulse stretcher Balanced Unbalanced 3.3V

Quantum Encryption System - Synchronization Special components – Mono Stable Splitter ECL 1:2 D.D.L ECL From TTL To ECL D.D.L ECL Flip Flop CLK _Q_Q Q S D R '1' '0'

Quantum Encryption System - Synchronization Special components – Bal-UN Special components – Bal-UN Balanced to Unbalanced OUT 68Ω 140Ω 150Ω 1nF 100nF IN + -

Quantum Encryption System - Synchronization Optic Detector Board The optic detector board will receive optic signal and translate it to a balanced electric pulse. The board will supply the working needs for the Optic detector. Input : optic signal (Laser). Output : Balanced electric pulse.

Quantum Encryption System - Synchronization Aspects in choosing components Technological compatibility - (TTL/ECL, input and output voltage) – most of the components we chose works in TTL technology because we needed width pulse for the computer and to the long delay device. System compatibility - (with the transmitter, receiver and computer) – the transmitter output is an optic pulse so we needed to add an optic detector. The receiver input is in ECL technology so we need to convert the output technology to ECL. Short Trise and Tfall – because we deal with a short an accurate pulses. Available for purchase.

Quantum Encryption System - Synchronization System Inputs Optic Sync pulse from the transmitter – we will simulate this pulse with a laser to test our system before integration with the transmitter. STR1 & STR2 pulses from the receiver – feedback to check the photon arrival. We will simulate this pulse with the FPGA to test our system before integration with the receiver. SYNC_START from the PC – starting the calibration sequence. We will assign switch on the board to simulate SYNC_START command.

Quantum Encryption System - Synchronization System Outputs Delayed electric Sync to the receiver – the pulse will be delayed according to the photon arrival, we will be able to test this pulse with a scope in the reference test points. D.D.L control from FPGA – controlling the D.D.L delay – a binary word that will translated to delay in the D.D.L. MIX_Enable from FPGA – MIX Enable=‘1’ while calibrating the system, MIX Enable=‘0’after calibration is over - reactivate the MIX in receiver. Sync_end form FPGA – Informing the computer that the calibration is over.

Quantum Encryption System - Synchronization Hardware specification We will need 9V transformer for the optic detector board. All the parts we selected in the synchronization will need 5V power supply. Scope for checking the system performance. Laser for simulating the optic input pulse.

Quantum Encryption System - Synchronization Logic design of the FPGA software

Quantum Encryption System - Synchronization Placing the photon in the first 0.5nSec of the window We will need to get probability statistics of detecting photons in order to determine the size of N/t – the number of detections in a given time.

Quantum Encryption System - Synchronization Time table: – Finalizing the component list to order and the ORCAD electric design for our system – Approving the pin to pin net list and building the manufacturing files needed, finalizing it and send it to manufacturing – Starting the FPGA tools learning and making the skeleton of the software.