Project Title:

Fiber-optic readout of superconducting A/D converter.

94-1	08.07	1190	A	

Fiber-optic readout of superconducting A/D converter. 

Abstract:

The interconnections needed to read electrical data from infrared 
focal plane arrays present a thermal load to the array module, with 
the wires acting as thermal leaks. Satellites using on-board cryo-
coolers need substantial power to maintain the cryogenic 
environment. For satellites sent into orbit carrying a finite 
amount of liquid helium, the mission life is effectively over when 
this supply runs out. Therefore, it is mandatory to look for 
alternative methods to couple data from the 'cooled' array to the 'warmer' 
environment of the satellite. The use of optical fiber links between sensors 
and data transmission electronics can substantially reduce the heat load by 
transmitting data from the sensor environment via low thermal conductivity 
optical fiber. HYPRES is pleased to present a program to demonstrate the use 
of optical fiber links to read data from a superconducting analog to digital 
(A/D) converter. This technique is based upon the the use of laser diodes 
operating at cryogenic temperatures with greatly reduced power requirements. 
In Phase I we will demonstrate the operation of a superconducting A/D 
converter coupled to an optical readout link. 

This program will lead to the development of electronic sytems suitable for 
use on satellite infrared focal plane array readouts, permitting longer 
mission lifetimes. The application of cryogenic/room temperature optical 
links to superconducting circuitry can lead to potential commercial 
applications including superconducting/optical ATM (asynchronous transfer 
mode) network switch nodes directly compatible with fiber optic networks, 
ultra-fast memory modules, and optical interconnects for massively paralled 
processors. 

Key Words

HYPRES, Inc.        
175 Clearbrook Road
Elmsford, New York 10523