A 4 X 4 superconducting Batcher-Banyan switch

The paper describes a Batcher sorter and a Banyan network which together form a nonblocking and self-routing switch. The Batcher sorter sorts input packets in the order of their address values. This sorting operation guarantees no blocking in the succeeding Banyan network and presents an efficient way to check contention. The Banyan network distributes contention-free packets to their final destinations. The Batcher and Banyan switches were designed by using a three-junction SQUID gate family driven by three-phase powering clocks. The Batcher sorter is composed of 2/spl times/2 Batcher switching elements. Each Batcher switching element sorts two input packets in the order of their address values. A 4/spl times/4 Batcher sorter with 2-b data width, which is composed of six 2/spl times/2 Batcher switching elements, was fabricated by an Nb tri-layer process. Its correct operation was confirmed. The Banyan network consists of 2/spl times/2 Banyan switching elements. A 2/spl times/2 Banyan switching element with 2-b data width was also fabricated. The correct operation was confirmed up to 4 GHz by using a test pattern generator integrated on-chip.