A seesaw-type MEMS switch with enhanced contact force: the first results

Outstanding working characteristics make microelectromechanical systems (MEMS) switches attractive for many applications. However, the lack of reliability prevents their commercial success. Due to the small size, MEMS switches develop low contact force compared to their macroscopic counterparts, which leads to instability and fast increase of the contact resistance. This work describes the switch providing significantly larger force than the previously reported device. The enlargement is achieved by the modified shape of the beam and electrodes with the same footprint and lower actuation voltage. Design, simulation, fabrication and first experimental results for the switch are presented.

CMOS voltage-controlled oscillator with high-performance MEMS tunable inductor

LC CMOS voltage-controlled oscillators (VCOs) with tunable inductors are essential for high-performance, multi-band communication systems, such as IoT applications and 5G communication. However, VCOs that use CMOS tunable inductors have difficulty in achieving high RF performance due to the low Q-factor of the inductor. In addition, previously reported CMOS VCOs integrated with MEMS inductors have used CMOS switches for tuning frequency bands, but they also had large signal losses on the switch. Herein, we propose a CMOS VCO that is integrated with a MEMS tunable inductor that tunes the frequency band with three MEMS switches. The proposed MEMS tunable inductor enables us to achieve high RF performance due to the suspended structure, and RF MEMS switches enable lower signal loss than CMOS switches. In this work, we successfully fabricated the proposed CMOS VCO integrated with a MEMS tunable inductor using the flip-chip bonding process, and we measured oscillation frequencies according to the actuation of the three switches. The oscillation powers were measured as − 3.03 dBm @ 1.39 GHz, − 5.80 @ 1.98 GHz, − 7.44 dBm @ 2.81 GHz, and − 8.77 dBm @ 3.68 GHz.

HALF-WAVE DIPOLE WITH AN ACTIVE REFLECTOR BASED ON OPTO-CONTROLLED METAMATERIAL

Для обеспечения радиосвязи применяются различные конструкции антенн, которые могут обладать всенаправленными или узконаправленными диаграммами направленности, при этом наибольшей защитой канала связи от помех и от перехвата обладают направленные антенны. Но их недостатком является то, что для обеспечения связи во всех направлениях требуется или установка группы антенн, или использование поворотных платформ, которые ухудшают показатели надежности системы, а также усложняют ее. Поэтому, как правило, для обеспечения связи применяют всенаправленные антенны, которые имеют диаграмму направленности в виде тороида. Недостаткaми таких антенн являются малый коэффициент направленного действия, а также прием большого числа шумов, что усложняет последующую обработку сигналов. Предлагается конструкция дипольной антенны, помещенной в активный метаматериал, с возможностью формирования луча путем коммутации слоев конструкции, что формирует динамически перестраиваемые рефлекторы. Получаемые в процессе функционирования системы диаграммы направленности обладают высокими значениями КНД, а также высокой помехозащищённостью и защитой от перехвата ввиду направленных свойств. Была получена конструкция антенны, помещенная в кубическую структуру активного метаматериала, с возможностью коммутации проводников с использованием pin-диодов или МЭМС-коммутаторов, что позволяет обеспечить быстрое переключение режимов работы устройства, формирование направленного луча и обеспечение помехозащищенной и защищенной от перехвата связи To ensure radio communication, various antenna designs are used, which can have omnidirectional or narrowly directional radiation patterns, while directional antennas have the greatest protection of the communication channel from interference and interception. However, their disadvantage is that to ensure communication in all directions, either the installation of a group of antennas or the use of turntables are required, which degrade the reliability of the system, as well as complicate it. Therefore, as a rule, to provide communication, omnidirectional antennas are used, which have a radiation pattern in the form of a toroid. The disadvantage of such antennas is, as a rule, a small directional coefficient, as well as the reception of a large number of noises, which complicates the subsequent signal processing. In this work, we propose a design of a dipole antenna placed in an active metamaterial with the possibility of forming a beam by switching the layers of the structure, which forms dynamically tunable reflectors. Directional patterns obtained in the course of system operation have high directivity values, as well as high noise immunity and protection against interception due to directional properties. As a result of the study, we obtained an antenna design, placed in a cubic structure of an active metamaterial with the possibility of switching conductors using pin diodes or MEMS switches, which allows for fast switching of device operating modes, formation of a directed beam and providing noise-immune and interception-proof communication