Optical implementation of an ecient modi®ed signed-digit trinary addition
نویسنده
چکیده
Ecient parallel schemes for carry-propagation-free addition of modi®ed signed-digit trinary numbers are presented. The necessary minterms for implementation using an optical programmable logic array area are derived. The proposed schemes require only a truth table of 25 entries compared with an earlier scheme of 625 entries. The proposed schemes are amenable to optical implementation. Experimental results using an optical programmable logic array are demonstrated. The experiments show the problems of noise and crosstalk. This suggests some dc bias is necessary to increase the signal-to-noise ratio of the optical circuit. # 1998 Published by Elsevier Science Ltd. All rights reserved.
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Recoded and nonrecoded trinary signed-digit adders and multipliers with redundant-bit representations.
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