James T. Aberle

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This paper discusses the implementation of an automatic antenna tuning unit system (ATU) for software-defined and cognitive radio. The ATU simplifies radio frequency (RF) front-end design for multi-band, multi-mode radios by allowing an electrically small reconfigurable antenna to become a frequency-agile selective component (essentially a tunable filter).(More)
Fig. 5. Input impedance of the wideband patch antenna with capacitive probe feed. benefits of the subdomain attachment mode over the entire-domain attachment mode is that it can be used with any shape of patch and that it is faster to evaluate. The entire-domain attachment mode has to be derived from scratch for other shapes of patches. One uncertainty(More)
This paper proposes a novel RF front-end architecture for software-defined radios (SDRs) based on an electronically tunable antenna pair controlled by an antenna control unit (ACU) consisting of field effect transistor (FET) switches and a field pro-grammable gate array (FPGA). The fundamental gain-bandwidth limitations of electrically small antennas(More)
In this paper, the execution of rectangular patch antenna is mended applying a newly cylindrical electromagnetic band-gap (EBG) substrate. The microstrip patch antenna is fed in the driven terminal. This EBG structure, when constituted with microstrip patch antenna to radiation pattern and return loss got from menstruation appearance a better impedance(More)
In this paper, the execution of rectangular patch antenna is mended applying a newly cylindrical electromagnetic band-gap (EBG) substrate. The microstrip patch antenna is fed by the driven terminal. This EBG structure, when comprised with microstrip patch antenna to radiation pattern and return loss got from menstruation appearance a better impedance(More)
iii ABSTRACT The radiation pattern of an antenna array depends strongly on the weighting method and the geometry of the array. Selection of the weights has received extensive attention, primarily because the radiation pattern is a linear function of the weights. However, the array geometry has received relatively little attention even though it also(More)
ii ABSTRACT A dual-channel directional digital hearing aid (DHA) front-end using a fully differential difference amplifier (FDDA) based Microphone interface circuit (MIC) for a capacitive Micro Electro Mechanical Systems (MEMS) microphones and an adaptive-power analog font end (AFE) is presented. The Microphone interface circuit based on FDDA converts the(More)
i ABSTRACT A dual-channel directional digital hearing aid (DHA) front end using Micro Electro Mechanical System (MEMS) microphones and an adaptive-power analog processing signal chain is presented. The analog front end consists of a double differential amplifier (DDA) based capacitance to voltage conversion circuit, 40dB variable gain amplifier (VGA) and a(More)