Optical binary logic gate-based modified signed-digit arithmetic

✍ Scribed by R.S Fyath; A.A.W Alsaffar; M.S Alam

• Publisher: Elsevier Science
• Year: 2002
• Tongue: English
• Weight: 202 KB
• Volume: 34
• Category: Article
• ISSN: 0030-3992
• DOI: 10.1016/s0030-3992(02)00015-4

✦ Synopsis

A new design approach for a three-step modiÿed signed-digit (MSD) adder is presented that can be optically implemented using binary logic gates. The proposed scheme depends on encoding each MSD digits into a pair of binary digits using a two-state and multi-position encoding scheme. The proposed design algorithm depends on constructing the addition truth table of binary-coded MSD numbers and then using Karnaugh map to achieve output minimization. The optical binary logic gates are obtained by simply programming the decoding masks of a shadow-casting-based optical logic gate system. The proposed scheme results in a simple, compact, and e cient optical binary gate-based parallel addition system.