Optical crossbar network MILORD machine: last developments and results

We present here the state of development of our MILORD machine. MILORD is a multiprocessor architecture organized around a 32 x 32 optical crossbar network. This network interconnects 16 INMOS T4 14 microprocessors with four bidirectional links each. Once the system integration was made, we have noted the existence of errors on the optical links caused by the presence of modal noise at the output of the optical fibers. A theroretical analysis of modal noise effect is presented and solutions to avoid it in optical networks are proposed. This study is still in progress at the Optics Department. We examine the possibilities to improve the three main parameters of such networks : the number of links, the reconfiguration time, the data rate. We give a theoretical and quite general analysis about the bit error rate performance as a function of the mean power available at each output of such matrixvector inner product optical networks.