V. Silva Cortes

Shunt MEMS switch requirements for Tunable Matching Network at 1.9 GHz in composite substrates

A theoretical approach for the specification of shunt MEMS switches suitable for Tunable Matching Networks (TMN) at 1.9GHz is presented. DC-contact fixed-fixed beam MEMS switches designed with series metal-insulator-metal (MIM) capacitors at the grounding plane of a CPW transmission line provide the basic design block for the TMN. In the down-state, the MEMS switch makes an ohmic contact with the transmission line, as consequence, the down-state capacitance of the switch is dominated by the MIM capacitors. The proper dimensioning of the MIM capacitors enables to directly increase the capacitance ratio of the switch in order to operate at frequencies below 10 GHz. Based on predefined CPW transmission line configurations on composite substrates, the optimization of the capacitance ratio of the MEMS switch can be directly related to the geometry of the CPW transmission line.

Modeling of BAW filters for system level simulation

A behavioral model of a BAW resonator realized in VerilogA is presented. VerilogA models can be integrated in all leading RF design tools allowing simulations of BAW filters at a system and circuit level. In that way a coupled design of the conventional electronics and the electro-mechanical BAW is now possible. By using the presented model the system designer has the possibility to optimize both the conventional electronic and BAW components according to the system requirements simultaneously. The VerilogA model has been verified by performing optimization in Cadence and ADS.

Nonlinear BAW filter model effects on the performance of an LTE receiver

In this work, the impact of the intrinsic nonlinear effects of bulk acoustic wave (BAW) filters on the demodulation performance of an LTE user equipment (UE) receiver at 2600 MHz is evaluated. The nonlinear effects that shape the generation of higher harmonics in the BAW resonator are covered in a nonlinear model implemented in Keysights advance design system (ADS) and validated through nonlinear measurements for its second order harmonic response. By means of a polyharmonic distortion (PHD) model, the nonlinear characteristics of the BAW filter are captured. Allowing to co-simulate the PHD model of the BAW filter with an standard LTE receiver. Thus, its impact on the performance of current communication standards can be assessed prior manufacturing.

High power effects on a MEMS-based tunable matching network for power amplifier reconfigurability

In this work, the thermal effects of a tunable matching network (TMN) based on micro electro mechanical systems (MEMS) are investigated. A reconfigurable power amplifier (PA) is proposed based on a TMN. The thermal effects are modeled and their influence on the linearity of the PA are addressed. The study is aided by a behavioral model of the capacitive MEMS switch which has been extended in order to include the thermal effects that raise due to power dissipation at the MEMSs membrane. The PA architecture is based on a commercial process design kit and the MEMS switch is based on the geometry and material characteristics of an available component.

Evaluation of a multiphysical RF MEMS oscillator based on LTE receiver performance requirements

A simulation methodology dealing with the complexity of multiphysical micro electro mechanical system (MEMS) models and their evaluation according to RF specification is presented. It is focused towards the evaluation of a hybrid MEMS-CMOS RF oscillator prior to its realization, based on the demodulation performance of a long-term evolution (LTE) user equipment (UE). The proposed multiphysical simulation approach enables to meet the constraints of the receiver specification, the design rules for manufacturing and the implementation with the novel silicon-ceramic composite substrate (SiCer) based on co-simulation and a parametrized behavioral model of the MEMS resonator. Thus, allowing to successfully address the constraints at the different abstraction levels of the design and manufacturing processes.