Magnetic quantum-dot cellular automata (MQCA) is a new kind of unconventional computation structure that uses solitons or domain walls propagating in field coupled magnet dots to implement signal propagation. Input and output structures are required as an interface between MQCA and the outside circuit. Input structures "write" a particular state to magnet dots, and output structures "read" out the state. Several kinds of input and output realization structures are reviewed in this thesis, of which technologically undemanding structures are picked up as promising candidates because of the simple operation of the MQCA structure. A joint experimental and theoretical approach of AMR-based magnetic sensor is undertaken; as the resistance change of the sensor is predicted using micromagnetic simulations. Simulation and measured resistance vs. magnetic field change curves show good agreement on a simple test device and mesoscopic magnet wire.