UCSD ECE 191 Winter 2018 01 August 2018

UCSD ECE 191 Winter 2018 01 August 2018 Modulator/Demodulator for Optical Communication Team: Jason Kelley Jin Choe Michael Lindarto Stephanie Lugo Sponsor: Mentors: Aaron Freeman David Robie 1

Project Description • Develop a direct detection optical communication system – Free space laser communication • Simultaneously transmit and receive data – 620 Mbps • The system will use pulse position modulation Electronics Weekly. “https: //www. electronicsweekly. com/news/business/free-space-opticalcomms-gets-nearer-2017 -10/” 2

Current Progress • High performance and low cost layouts complete – In review by GA personnel • Moving to BASYS 3 FPGA Dev Board https: //www. eevblog. com/forum/microcontrollers/basys 3 -connected-tosmartphone/? action=dlattach; attach=227683; image 3

Project Schematic • Two Designs – High Speed – Low Speed, Low Cost 4

Tx Basic Schematic 5

Tx Board Layout 6

Rx Basic Schematic 7

Rx Board Layout 8

Low Cost 9

Low Cost Tx 10

Low Cost TX Layout 11

Low Cost Rx 12

Low Cost RX Layout 13

FPGA Modulation Scheme 14

FPGA Demodulation Scheme 15

Gantt Chart 16

Goals for coming weeks • Send layouts to board house for fabrication • Develop test plan • Assemble hardware • Begin loading/testing modulation on FPGA/Arduino 17