Apparatus and method for adjusting the phase-modulator's modulating signal time reference in a quantum-key-distribution system
Номер патента: EP4295529A1
Опубликовано: 27-12-2023
Автор(ы): Atul Kumar Gupta, Prasanta Halder, Prashant Kumar RATHORE, Roshan Lal SHARMA, VIVEK Kumar
Принадлежит: CENTRE FOR DEVELOPMENT OF TELEMATICS, Centre for Development of Telematics C DOT
Опубликовано: 27-12-2023
Автор(ы): Atul Kumar Gupta, Prasanta Halder, Prashant Kumar RATHORE, Roshan Lal SHARMA, VIVEK Kumar
Принадлежит: CENTRE FOR DEVELOPMENT OF TELEMATICS, Centre for Development of Telematics C DOT
Реферат: The present disclosure relates to the field Quantum Key distribution (QKD) and discloses an apparatus (100) and method (300) for adjusting the phase modulator's modulating signal time reference in a phase-based QKD system. The QKD system comprises a pulse generator (10) that generates optical pulses and a phase modulator (20) that modulates the phase of each of the pulses. The apparatus (100) comprises a beam splitter/tap (112), a 1-bit delay interferometer (110), two photodetectors (106,108), and a processing device (104). The splitter feeds the phase modulated optical pulses to the interferometer (110). Two photo detectors are connected to the constructive and destructive output legs (110a,110b) of the interferometer (110). The photo detectors' output are then converted to digital signals and fed to the processing device (104). The processing device (104) measures the average power at both the legs of the interferometer (110) to detect delay between optical signal and modulating signal and adjusts the delay to accurately align the phase modulator (20) with the pulse generator (10).
Apparatus And Method For Adjusting The Phase-Modulator's Modulating Signal Time Reference In A Quantum-Key-Distribution System
Номер патента: US20240039635A1. Автор: VIVEK Kumar,Prasanta Halder,Atul Kumar Gupta,Roshan Lal SHARMA,Prashant Kumar RATHORE. Владелец: Centre for Development of Telematics C DOT. Дата публикации: 2024-02-01.