摘要:
Systems and methods of detecting wireless channel status from acoustic discrimination of spectral content are described. In one aspect, a wireless system includes a spectrum analyzer, a detector, and a controller. The spectrum analyzer is operable to acoustically discriminate spectral content of an input electrical signal in multiple discrete frequency channels. The detector is operable to determine respective statuses of the frequency channels from the acoustically discriminated spectral content. The controller is operable to select one of the frequency channels based on the determined statuses of the frequency channels.
摘要:
A spread-spectrum radio, such as a frequency-hopping spread-spectrum radio or a direct-sequence spread-spectrum radio, includes a transmitter that utilizes microelectromechanical systems (MEMS) based oscillation system to generate a spread-spectrum signal and/or a receiver that utilizes a MEMS-based frequency selection system to receive a spread-spectrum signal. In an embodiment, the MEMS-based oscillation system and the MEMS-based frequency selection system utilize MEMS resonators such as thin film bulk acoustic resonators (FBARs) that are fabricated in high density on a single substrate.
摘要:
A piezoelectric cantilever pressure sensor has a substrate and a piezoelectric cantilever having a base portion attached to the substrate and a beam portion suspended over a cavity. The piezoelectric cantilever contains a piezoelectric layer sandwiched between two electrodes and generates a measurable voltage when deformed under pressure. The piezoelectric cantilever pressure sensor can be manufactured at low cost and used in various applications including fingerprint identification devices.
摘要:
A power supply comprises an AC-DC converter circuit, which comprises a first capacitor and a second capacitor. The converter also comprises a rectifier circuit connected to the first and second capacitor and operative to charge both the first and the second capacitor and to discharge the first capacitor independently of the second capacitor. The power supply also comprises an acoustic transformer.
摘要:
A navigation system including a first navigation sensor configured to provide a first set of positional capacitance values, a second navigation sensor configured to provide a second set of positional capacitance values, and a controller configured to select between the first and second sets of positional capacitance values and to provide navigation information selectively based on the first and second sets of positional capacitance values.
摘要:
A method and apparatus for detecting a location of an eye of a user using an automated detection process, and automatically determining a position of a head of the user with respect to an object based on the detected location of the eye. A location of an eye of a user inside a vehicle is detected using the automated detection process, at least one of height and orientation information of the user is automatically determined based on the detected location of the eye, and a mechanical device inside the vehicle is controlled in accordance with the determined information. Moreover, an eye blinking pattern of a user is detected using an infrared reflectivity of an eye of the user, and messages are transmitted from the user in accordance with the detected eye blinking pattern of the user.
摘要:
A first and a second resonator are fabricated monolithically adjacent to one another. The first resonator is the reference resonator. The resonant frequency of the second resonator is offset by a difference frequency Fo from the first resonator. Each resonator is included within an oscillator. A mixer receives the output of both oscillators. A low pass filter receives the mixer output and generates a clock signal whose frequency is equal to the difference frequency Fo.