Substantial improvements in the far-from-carrier phase noise of oscillators referenced to stand-alone (as opposed to arrayed) capacitively transduced micromechanical disk resonators have been attained via the use of atomic layer deposition (ALD) to tune the electrode-to-resonator capacitive gaps. Specifically, ALD of about 30nm of hafnia (HfO 2 ) onto the surface of a released 60-MHz micromechanical disk resonator to reduce its effective resonator-to electrode gap size from 92nm to 32nm provides an increase in power handling leading to more than 15-20dB reduction in the far-from-carrier phase noise of an oscillator referenced to this resonator. This ALD-enabled nano-scale gap tuning provides a simple and effective method to satisfy increasing demands for higher short-term stability in frequency references for electronic applications.

A micromechanical displacement amplifier comprising two asymmetric resonator array composites coupled by a quarter-wavelength beam has been demonstrated that permits specification of gain factor by mere (digital) selection of an appropriate ratio of the number of resonators in an input array to that in an output array. Like the method of [1], this displacement gain circuit is a key enabler for resoswitch-based mechanical power amplifiers and power converters, because it can prevent unwanted drive electrode-to-resonator impact in such circuits. This design, however, differs from that of [1] in that 1) it can be applied to radial-contour mode disks that can achieve much higher frequency than the wine-glass disks of [1]; 2) it preserves the frequency and Q of its constituent resonators (whereas the method of [1] changed the frequency and lowered the Q); and 3) its digital method for gain specification is much more straightforward, accurate, and repeatable.

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A W-band target glint and background scene generator is developed for compact range hardware-in-the-loop (HWIL) seeker testing and characterization. The device comprises an Electronically Controlled Beamformer (ECB) capable of real time generation of wide variety of wavefronts in the near field of the system under test (SUT). The fine-pixelized ECB aperture with individual control of each pixel allows (in particular) formation of radar returns in a compact range by focusing and steering the (focused) Millimeter Wave (MMW) beam on the SUT aperture. Unlike compact range systems using limited number of radiators and focal plane optics, fine-pixelized ECB allows full glint simulation over SUT's field of view. ECB is compatible with currently used retransmitter and waveform simulator. We present the results of a simulation of the device's operation and compare them with the experiment. Major attention in both the simulations and the measurements was paid to the field distribution in the near-field region of the device.

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