Designing a New Ternary Arithmetic Unit with Overflow Detection Using Reversible Ternary
Abstract
Reversible ternary circuit design has attracted considerable attention because ternary logic can reduce interconnection complexity relative to binary logic and is compatible with emerging quantum-computing and nanotechnology platforms. This study proposes a reversible 2-trit ternary parallel adder with a quantum cost of 23, one constant input, and three garbage outputs. Compared with previously reported counterparts, the proposed adder requires lower quantum cost and fewer constant inputs and garbage outputs. Based on this adder, a reversible arithmetic unit is developed for two 2-trit unsigned ternary numbers. The unit performs six arithmetic operations: A+B, A−B, A+1, A−1, A+B+1, and A−B−1. The unsigned inputs and outputs are represented within the decimal range from 0 to 8. A reversible arithmetic unit for two signed 2-trit ternary numbers is also proposed. This circuit has a quantum cost of 32 and requires only one constant input. It performs the same six arithmetic operations using the 3’s-complement representation over the range from −4 to +4. In addition, a new reversible overflow detection module is introduced for signed addition and subtraction. By integrating this module with the proposed signed arithmetic unit, a complete reversible ternary arithmetic circuit with overflow-detection capability is obtained. All proposed circuits are constructed using 1-qutrit shift gates and 2-qutrit Muthukrishnan–Stroud gates, which are primitive ternary gates suitable for implementation in ion-trap quantum-computing technology.