Image Processing Algorithms Implementation Using Quantum Cellular Automata - Cellular Automata in Image Processing and Geometry - page 69

A

B AB

0

Fig. 4.7 The logic AND gate designed using QCA cells

35, 65], flip-flop [17, 38, 53], arithmetic logic units (ALUs) [43, 59] and serial or
parallel memories [35, 58, 64, 65].
By using QCA technology, the integration can reach densities of 10 12 devices/cm 2
and the circuit switching frequency can be close to terahertz [19]. Although, the
main advantages of QCA designs are the improvement that offer in size, speed and
power consumption, there are also some other characteristics that give advantage to
QCA technology, such as the ability to cross wires in a plane [62] and a new com-
putation and information representation method which is referred to as processing-
in-wire [28]. Therefore, QCA is a new opportunity for the design of highly parallel
algorithms and architectures.
But, there are also some problems in the realization of QCA technology. The sta-
bility of a QCA circuit is based on the assumption that the system falls to the ground

A

B A+B

1
Fig. 4.8 The logic OR gate designed using QCA cells