Improving the Throughput of On-line Addition for Data Streams

In this paper we deal with the throughput of on-line addition for a stream of data. This throughput is directly related to the initiation interval between two successive instances. The on-line delay for the addition of two signed-digit (or carry-save) numbers is two, and N+2 cycles are classically used to compute a new pair of N- digit data (initiation interval: N+2). In this paper we present some techniques to reduce the initiation interval to N (which is the theoretical minimum value) with a very small amount of hardware or N+1 with no hardware cost. For short operands, this might have a significant effect on the throughput.