FDTD Analysis of Active Integrated Antenna with Amplifier

摘要

In this paper, an FDTD analysis is carried out for an active integrated antenna with an amplifier. The GaAs FET used in the amplifier is expressed in terms of TriQuint's Own Model (TOM) and the numerical results of its state equation are combined with the FDTD method by way of the voltage source method. As a result of investigation of the method for application of the bias voltage in a 8.5-GHz low-noise amplifier, it is found that convergence to the set voltage is obtained by applying the voltages via shorting pins after all bias circuits are modeled. Also, the analysis and experimental results of the radiation patterns of the active patch antenna are compared. It is found that the cross polarization level is increased due to the currents flowing in the drain bias line placed near the patch antenna. Finally, the radiation characteristics of the active slot antenna are investigated. It is confirmed that the cross polarization can be reduced by separating the radiating part and the circuit part on opposite sides of the substrate. The method proposed in this paper allows design of the entire antenna structure integrated with active devices, including the effect of the coupling between the circuit elements, impedance matching conditions, and radiation patterns.