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Buchele and Associates, Inc.
Characterization of ASIC and Device Packaging
Figure 1. shows simulation results for an evaluation ASIC and associated wiring. Current density is depicted as a false color plot on the conductors. A 'Method of Moments" simulator (IE3D) was used for this example. 
    The simulation and optimization of ASIC interconnects and packaging at microwave frequencies requires a full-wave simulation of the device geometry. Typically the goal is to fully model all signal paths to characterize discontinuities and crosstalk associated with wirebonds, vias, board traces, packaging and integrated circuits. Impedance and crosstalk parameters are extracted as multi-port S-parameters.  If required they can be converted to circuit elements (LRCM) useful in most Spice-like circuit simulators.
Design and Characterization of RF and Microwave Devices and Antennas
Figure 2. shows a two-section multi-layer spiral inductor fabricated on a silicon chip. Magnetic field intensity is plotted on a section-plane above the spirals. A "Method of Moments" simulator (IE3D) was used for this analysis.
    In this example three-port S-parameters were extracted. A wide-band mathematical LRCM model of the inductor network was synthesized. A derived LRCM model or S-parameters may be imported into a compatible simulator along with an RF ASIC and the device performance evaluated.
Figure 1.
Figure 3.
Design and Analysis of Inductively-Powered Implanted Medical Device
Figure 3. shows an external induction-coil providing power to an implanted medical device.  Operating at RF frequencies (HF Band) the antenna powers electronics and related circuitry within a device implanted in the human body.
    In this case power is dissipated in the human tissue layers and the implanted device. The relative magnitude of the power dissipation (mw/cc) is shown highlighted in lighter colors. A Finite Element (FEM) simulator (Maxwell 3D) was used for this analysis.
Figure 2.
Figure 3.
Antenna Design
Figure 4. shows a cross-sectioned view of the Far-Field radiation pattern for a device operating in the 2.4GHz band (Bluetooth / WiFi). The complete module is 15X25mm. The area required by the printed antenna is approximately 15X6mm.  The antenna achieves good radiation efficiency (<2dB losses)  for an electrically short device.  S, Z and far-field radiation parameters are derived for the antenna which enable proper matching to the RF ASIC TX/RX port and calculation of the radiation pattern and efficiency.
A Finite Element (FEM) simulator (Ansoft HFSS) was used for this analysis.
Figure 4.
Analysis, Simulation and Design of Packaging,  Components and Antennas