Abstract: In one aspect, the invention provides a method implemented by an analog hardware circuit for fast frequency estimation. The analog circuit may be implemented a main oscillator circuit block [100], a P matrix circuit block [102], a K matrix circuit block[104], and a sigma integrator circuit block [106]. From input signals [108] having unknown frequency, amplitude and phase, the analog hardware circuit generates estimates of state variables xi, x2, x3 of a model oscillator, and outputs a sinusoidal estimate [110] of the model oscillator signal. The analog hardware circuit generates the estimates by implementing in continuous time an extended Kalman filter that relates a generating frequency 107 of the model oscillator to x3 by an affine transformation ?=?0+£x3, where k is a slope of a frequency error estimate and coo is a best estimate input signal frequency.

Abstract: In one aspect, the invention provides a method implemented by an analog hardware circuit for fast frequency estimation. The analog circuit may be implemented a main oscillator circuit block [100], a P matrix circuit block [102], a K matrix circuit block[104], and a sigma integrator circuit block [106]. From input signals [108] having unknown frequency, amplitude and phase, the analog hardware circuit generates estimates of state variables x, x2, x3 of a model oscillator, and outputs a sinusoidal estimate [110] of the model oscillator signal. The analog hardware circuit generates the estimates by implementing in continuous time an extended Kalman filter that relates a generating frequency co of the model oscillator to x3 by an affine transformation ?=?0+£x3, where k is a slope of a frequency error estimate and coo is a best estimate input signal frequency.

Abstract: A high-Q precision integrated reversibly trimmable singleband oscillator and tunable multiband oscillator are presented that overcome the problems laser trimming and solid state switches. This is accomplished using micro-electromechanical system (MEMS) technology to integrate an amplifier and its tunable LC network on a common substrate. The LC network can be configured to provide a very narrow bandwidth frequency response which peaks at one or more very specific predetermined frequencies without de-Qing the oscillator.

Abstract: Power amplifiers having reactive networks (such as classes C, C-E, E and F) employ tunable reactive devices in their reactive networks, with the reactive devices respective reactance values capable of being adjusted by means of respective control signals. The tunable reactive devices are made from micro-electromechanical (MEM) devices capable of being integrated with the control circuitry needed to produce the control signals and other amplifier components on a common substrate. The reactive components have high Q values across their adjustment range, enabling the amplifier to produce an output with a low harmonic content over a wide range of input signal frequencies, and a frequency agile, high quality output. The invention can be realized on a number of foundry technologies.

Abstract: A frequency stabilizer circuit in the form of a charge-pump phase-lock loop utilizing a MEMS capacitance device, preferably a tunable MEMS capacitor or a MEMS capacitor bank, which more rapid and with a greater precision determine the phase and frequency of a carrier signal so that it can be extracted, providing an information signal of interest. Such MEMS devices have the added advantage of providing linear capacitance, low insertion losses, higher isolation and high reliability, they run on low power and permit the entire circuit to be fabricated on a common substrate. The use of the MEMS capacitance device reduces unwanted harmonics generated by the circuit's charge pump allowing the filtering requirements to be relaxed or perhaps eliminated.

Abstract: The passive components of a transceiver, such as transmit/receive switches, antennas, inductors, capacitors and resonators, are integrated together on a common substrate to form an integrated passive transceiver section, which, in combination with other components, provides a highly reliable, low-cost, high-performance transceiver. Micro-electromechanical (MEM) device fabrication techniques are used to provide low-loss, high-performance switches and low-loss, high-Q reactive components, and enable the passive transceiver section's high level of integration. The passive components are preferably integrated on a low-cost glass substrate, with transceiver circuits containing active components fabricated on a separate substrate; the separate substrates are interconnected to implement the RF/analog and analog/digital interface portions of a transceiver. Additional MEM switching devices permit multiple, parallel signal paths to be switched in and out of the transceiver circuitry as needed to optimize performance.

Abstract: A high Q MEMS capacitor that can be continuously tuned with a large tuning ratio or reversibly trimmed using an electrostatic force. The tunable capacitor has a master/slave structure in which a control voltage is applied to the master (control) capacitor to set the capacitance of the slave (signal) capacitor to which an RF signal is applied via a suspended mechanical coupler. The master-slave structure reduces tuning error by reducing the signal capacitor's surface area and increasing its spring constant, and may eliminate the need for discrete blocking inductors by electrically isolating the control and signal capacitors. The trimmable capacitor provides an electrostatic actuator that selectively engages a stopper with teeth on a tunable capacitor structure to fix the trimmed capacitance.

Abstract: A monolithically integrated switched capacitor bank using MEMS technology that is capable of handling GHz signal frequencies in both the RF and millimeter bands while maintaining precise digital selection of capacitor levels over a wide tuning range. Each MEMS switch includes a cantilever arm that is affixed to the substrate and extends over a ground line and a gapped signal line. An electrical contact is formed on the bottom of the cantilever arm positioned above and facing the gap in the signal line. A top electrode atop the cantilever arm forms a control capacitor structure above the ground line. A capacitor structure, preferably a MEMS capacitor suspended above the substrate at approximately the same height as the cantilever arm, is anchored to the substrate and connected in series with a MEMS switch.

Abstract: An integrated, tunable inductance network features a number of fixed inductors fabricated on a common substrate along with a switching network made up of a number of micro-electromechanical (MEM) switches. The switches selectably interconnect the inductors to form an inductance network having a particular inductance value, which can be set with a high degree of precision when the inductors are configured appropriately. The preferred MEM switches introduce a very small amount of resistance, and the inductance network can thus have a high Q. The MEM switches and inductors can be integrated using common processing steps, reducing parasitic capacitance problems associated with wire bonds and prior art switches, increasing reliability, and reducing the space, weight and power requirements of prior art designs.

Abstract: An integrated, variable gain microwave frequency power amplifier comprises a number of individual amplifier stages which contain microwave frequency active devices. Each stage is fed with a common input signal, and the individual stage outputs are connected to respective micro-electromechanical (MEM) switches which, when closed, connect the individual outputs together to form the power amplifier's output. The power amplifier's gain is determined by the number of outputs connected together. The preferred switch provides low insertion loss and excellent electrical isolation, enabling a number of amplifier stages to be efficiently interconnected to provide a wide dynamic range power amplifier. The switches are preferably integrated on a common substrate with the active devices, eliminating the need for wire bonds and reducing parasitic capacitances.

Abstract: An optical modulator having a waveguide region comprising first and second layers of material having differing effective masses for free charge carriers at a predefined band edge energy disposed immediately adjacent to each other and covered by a lower refractive index cladding. A preferred embodiment employs a semiconductor system such as Al.sub.y Ga.sub.1-y As for the first and second material layers with the value of y adjusted between the layers so that the conduction band edge energies of the direct band in one layer is about the same as that of the indirect condition band in the other layer. A mechanism is provided for moving charge carriers between the first and second layers, such as metal contacts and a power source for applying electrical fields to the waveguide structure in a desired modulation pattern. The material layers may be deposited as a series of quantum wells with limited disordering or a ridge structure used to obtain lateral confinement.