مرجع [25] ضرب كننده با پيمانه هاي بزرگ به شكل () را مطرح كرد. [29] ضرب كننده پيمانه اي را مطرح كرده از Factored decomposition بهره گرفته و در آن پيمانه ها مي توانند اعداد غير اول باشد.
عمده اين روشها بر اساس بكارگيري عناصر رياضي binary-based هستند و هيچ كدام بجز طرح [16] براي استفاده از محاسبات مانده اي
(Residue Arithmatic) طراحي نشده اند.
3-3- الگوريتم
دو باقيمانده Y, X (Residue) را در نظر بگيريد هدف محاسبه |XY|m (حاصلضرب X و Y در پيمانه m) مي باشد. هر دو عدد را مي توان با n بيت نمايش داد:
كه در آن ها n برابر است:
و و بيت هاي باينري X و Y مي باشند. حاصلضرب X و Y را مي توان به صورت زير نمايش داد.
با بسط عبارت فوق داريم:
كه مي توان نوشت:
(3-1)
حالا را به صورت زير تعريف مي كنيم:
vj = (3-2)
بنابراين رابطه (3-1) به صورت زير بازنويسي مي شود:
(3-3)
و براي محاسبه معادله بالا به صورت زير در مي آيد:
(3-4)
3-4- پياده سازي سخت افزاري
شكل بلوكي سخت افزار اين طرح را در شكل (3-1) مشاهده مي كنيد. همانطور كه مشاهده مي شود، طرح پيشنهادي در چهارطبقه پياده شده است.
با دقت در رابطه (3-4) در مي يابيم كه براي پياده سازي اين طرح بايد تمام را محاسبه كرده و در انتها به صورت پيمانه اي با هم جمع كنيم. بررسي vj در رابطه (3-2) مشخص مي كند كه vj تعداد يك هاي نمايش باينري عبارت مي باشد.
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