Reversible logic has shown considerable acceptance and growth in the research fields like quantum computing, Nano computing and optical computing promising lower power dissipation.This paper proposes an optimised design single-bit reversible comparator called SKAR gate with a purpose of reducing quantum cost.Besides, this novel SKAR gate is used as a single-bit reversible comparator to construct an optimised design for a fourbit reversible comparator.The paper discusses two designs, one with the use of SKAR gate and other one using a derivative gate constructed from SKAR gate.Since the reversible logic aims at reducing the value of its fundamental parameters viz.quantum cost, garbage outputs, ancillary inputs, delay and number of gates; Both the proposed designs for single-bit and four-bit reversible comparator are compared with other existing designs on the basis of elementary parameters of reversible logic.
Reversible logic has shown considerable acceptance and growth in the research fields like quantum computing, Nano computing and optical computing promising lower power dissipation.This paper proposes an optimised design single-bit reversible comparator called SKAR gate with a purpose of reducing quantum cost.Besides, this novel SKAR gate is used as a single-bit reversible comparator to construct an optimised design for a fourbit reversible comparator.The paper discusses two designs, one with the use of SKAR gate and other one using a derivative gate constructed from SKAR gate.Since the reversible logic aims at reducing the value of its fundamental parameters viz.quantum cost, garbage outputs, ancillary inputs, delay and number of gates; Both the proposed designs for single-bit and four-bit reversible comparator are compared with other existing designs on the basis of elementary parameters of reversible logic.
Today, reversible logic circuits has attracted considerable attention in improving some fields like nanotechnology, quantum computing, and low power design. In this paper 4 bit reversible comparator based on classical logic circuit is represented which uses existing reversible gates. In this design we try to reduce optimization parameters like number of constant inputs, garbage outputs, and quantum cost. The results show that, the proposed comparator has 4 quantum cost and one constant input less than the prior design. 1
Reversible logic; transforms logic signal in a way that allows the original input signals to be recovered from the produced outputs, has attracted great attention because of its application in diverse areas such as quantum computing, low power computing, nanotechnology, DNA computing, quantum dot cellular automata, optical computing. In this paper, we design low power binary comparators using reversible logic gates. Firstly, single bit binary reversible comparator circuits are designed using different reversible gates along with proposed gate named Newly Proposed Gate. Then, these procedures are generalized for constructing binary n-bit reversible comparator circuit. The design synthesis consists of two parts: Comparator Cell and Propagator Cell. An algorithm, based on our proposed design, shows that proposed circuit reduces overall cost and it outperforms than existing sequential comparator circuits. Also, comparing with existing tree-based comparator circuit, proposed design reduces quantum cost, garbage output and gate count in a significance level which means better improvement as cost of any quantum circuit is directly associated with quantum cost, garbage output and gate count.
In recent years, research in reversible logic has attracted significance attention leading to different approaches such as synthesis, optimization, simulation and verification. In this paper, we propose Design of Efficient Reversible Binary Comparator. The input circuit and one-bit comparator cell using NOT, PG and CNOT gates are designed. The n-bit reversible binary comparator are designed using input circuit as first stage and one-bit comparator cell as second stage and so on. The Power consumption, Delay, Garbage outputs and Constant inputs are computed. It is observed that the Quantum cost and Garbage output values are less in the proposed technique compared to the existing approaches.
In recent years, reversible logic circuits have applications in the emerging field of digital signal processing, optical information processing, quantum computing and nano technology. Reversibility plays an important role when computations with minimal energy dissipation are considered. The main purpose of designing reversible logic is to decrease the number of reversible gates, garbage outputs, constant inputs, quantum cost, area, power, delay and hardware complexity of the reversible circuits. This paper reveals a comparative review on various reversible logic gates. This paper provides some reversible logic gates, which can be used in designing more complex systems having reversible circuits and can execute more complicated operations using quantum computers. Future digital technology will use reversible logic gates in order to reduce the power consumption and propagation delay as it effectively provides negligible loss of information in the circuit. Keywords: Garbage output, Power dissipation, quantum cost, Reversible Gate, Reversible logic,
Reversible logic has attracted significance attention in recent years, leading to different approaches such as synthesis, optimization, simulation and verification. In this paper, we propose the design and optimization of n-bit reversible binary comparator. The circuit for MSB and one-bit comparator cell using NOT, PG and CNOT gates are designed. The n-bit reversible binary comparator is designed using circuit for MSB as first stage to compare MSBs and one-bit comparator cell as second stage and so on to compare lesser significant bit positions. The power consumption, delay, garbage outputs and constant inputs are computed. It is observed that the quantum cost and garbage output values are less in the proposed technique compared to the existing approaches.
Reversible logic is one of the emerging technologies having promising applications in quantum computing. In this work, we present new design of the reversible BCD adder that has been primarily optimized for the number of ancilla input bits and the number of garbage outputs. The number of ancilla input bits and the garbage outputs is primarily considered as an optimization criteria as it is extremely difficult to realize a quantum computer with many qubits. As the optimization of ancilla input bits and the garbage outputs may degrade the design in terms of the quantum cost and the delay, thus the quantum cost and the delay parameters are also considered for optimization with primary focus towards the optimization of the number of ancilla input bits and the garbage outputs. Firstly, we propose a new design of the reversible ripple carry adder having the input carry Co and is designed with no ancilla input bits. The proposed reversible ripple carry adder design with no ancilla input bits has less quantum cost and the logic depth (delay) compared to its existing counterparts. The existing reversible Peres gate and a new reversible gate called the TR gate is efficiently utilized to improve the quantum cost and the delay of the reversible ripple carry adder. The improved quantum design of the TR gate is also illustrated. Finally, the reversible design of the BCD adder is presented which is based on a 4 bit reversible binary adder to add the BCD number, and finally the conversion of the binary result to the BCD format using a reversible binary to BCD converter.