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Thermocouple sensor for temperature measurement has been widely used, however, the increase of precision is constrained due to the shortcoming of hardware based or table look up method, especially with nonlinear adjustment and cold end compensation. A new method was presented to compensate nonlinearity and cold-side-offset for signal processing of thermocouple with RBF neural networks. The structure of RBF neural networks was proposed and optimized with genetic algorithm, the principle of temperature measurement with thermocouple was analyzed and the neural networks model for signal conditioning was created. The simulation experiments show that the algorithm can improve network generation ability and high accurate compensation and nonlinear adjustment for cold-side-offset was realized effectively.

The factors determining quantum efficiency of field-assisted InP/InGaAsP semiconductor photocathodes have been analysed in detail in the paper. The transmission process of electrons in the absorption layer and transferred-electron process in the emission layer as well as the escape probability of electrons in the surface of emission layer have been calculated quantitatively on the basis of continuity equations and tunnelling effect of quantum mechanics. The curves of quantum efficiency versus wavelength for various biases have been obtained. The results show that the quantum efficiency of semiconductor photocathode in the range 0.9-1.25μm can be risen two orders of magnitude or more under a proper bias. It is helpful in designing the structure of semiconductor photocathodes and choose the optimum conditions of operation.

The dark-current source of a semiconductor field-assisted photocathode has been theoretically analysed and calculated. Under a given temperature of operation, a principal source of dark-current emission from the cathode is the impact ionisation component of hot holes in the Schottky barrier range. A specific expression for the multiplication factor of the impact ionisation is obtained. According to the theoretical calculation, the emission intensity of dependence of dark-current on the applied bias, doping concentration and operating temperature has been predicted. It may be helpful to design a field-assisted photocathode and choose an optimum operation condition.

The chip scale wireless interconnect systems are analyzed in terms of bit error rate performance and studied in terms of their antennas in this thesis. First, a novel inter-chip RF-interconnect system is proposed and analyzed. The intra-chip wireless interconnect system is analyzed at 25 GHz for various digital modulation schemes. In addition, on-chip antennas for intra-chip wireless interconnects are studied, including dipole antennas, 60-GHz inverted-F and quasi-Yagi antennas, as well as monopoles. A novel intra-chip wireless interconnect system using on-chip meander antennas and ultrawide-band (UWB) radios that operate in 22-29 GHz is analyzed. Furthermore, LTCC-based on-package antennas for inter-chip wireless interconnects are studied, including a discrete beveled UWB antenna, a UWB integrated circuit package antenna (ICPA), and 60-GHz ICPAs. A novel interchip wireless interconnect system using on-package beveled antennas and UWB radios that operate in 3.1-10.6 GHz is analyzed. DOCTOR OF PHILOSOPHY (EEE)