VCSEL based high performance ATM switch

Abstract

Large-broadband ATM switching nodes will require novel hardware solutions which could benefit from the inclusion of optical interconnect technology, since electronic solutions are limited by pin out and by the capacitance/inductance ofthe interconnections. This paper describes, analyzes and provides preliminary data from a new three stage free space optical switch which utilizes VCSELs for the optical interconnections, a liquid crystal spatial light modulator (SLM) as a reconfigurable shutter and relatively simple optics for fan out and fan in. A custom CMOS chip is required to introduce a time delay in the optical bit stream and to drive the VCSELs. Analysis shows that the switch should be scaleable to 1024 input and output channels. This size switch requires an array of 2048 VCSELs. A detailed optical power budget calculation indicates that each of the VCSELs in the array must have a maximum optical output of /spl sim/2 mW.