31 results about "Relative attenuation" patented technology

Circuits and methods for eliminating or mitigating the amount of temperature-dependent variation in the relative attenuation of a multi-valued digital step attenuator (DSA) by using resistive components having temperature-dependent resistance values that compensate for or offset changes in the temperature-dependent ON resistance (RON) of the switches within the DSA. In some embodiments, DSA attenuator cell switches are fabricated to have positive first-order resistance temperature (FORT) coefficients, while temperature-compensating series attenuation resistances are fabricated as a positive FORT coefficient resistor and temperature-compensating shunt resistances are fabricated as either a negative FORT coefficient resistor or a combination of a negative FORT coefficient resistor in parallel with a positive FORT coefficient resistor.

A large-mode-area (LMA) optical fiber (10) that operates as a single-mode optical fiber. The optical fiber includes a core region (20) surrounded by an inner cladding (32), which in turn is surrounded by an outer cladding (40). The inner cladding includes at least one up-doped ring region (32R1). The ring region is configured to form a large attenuation differential between the higher-order modes and the fundamental mode so only that the fundamental mode remains traveling in the optical fiber. If necessary, the optical fiber can include a bend (10B) having a select “resonant” bend diameter (DB) that increases the relative attenuation of the fundamental and higher-order modes. The optical fiber supports an effective mode field diameter (MFD) of up to 40 μm to 50 μm. As a result, detrimental non-linear effects are suppressed, which allows the optical fiber to carry substantially more optical power than conventional LMA optical fibers. The LMA optical fiber is thus eminently suited for a number of optical-fiber-based applications calling for high optical power, such as fiber lasers and pump sources for wavelength conversion.

The invention provides a catheter (12) comprising longitudinally spaced acoustic emitters (S1, S2) and receivers (M1, M2, M3) for use in determining the locations of obstructions in an upper airway ofa patient. A plurality of emitters and plurality of receivers are provided, such that, when inserted into an upper airway or oral cavity, the relative attenuation of signals received at each receiverfrom each emitter may be used to determine the existence and / or extent of obstructions located along the propagation path between each of the various emitter-receiver pairs. Also provided are methodsfor determining the locations of obstructions in an upper airway using signals received from acoustic receivers as comprised by catheter arrangements according to embodiments of the invention.

The invention relates to a method for directional signal processing for a hearing instrument, wherein a first input signal is generated from an ambient sound signal, wherein a second input signal is generated from an ambient sound signal, wherein a first and a second input signal are generated The two input signals generate a first calibrated orientation signal having relative attenuation in the direction of the first useful signal source of the environment, wherein, based on the first and second input signals, a second calibrated orientation signal is generated, the second calibrated orientation signal at There is a relative attenuation in the direction of the second useful signal source of the environment, wherein a relative amplification parameter is determined from the first and second calibration directional signals, wherein the first and second processing are generated from the first and second input signals, respectively A directional signal, wherein a source sensitive directional signal is generated from the first processed directional signal, the second processed directional signal and the relative amplification parameter, and wherein an output signal of the hearing device is generated from the source sensitive directional signal.

The invention discloses a quick speed blind source separation method based on frequency point selection under binaural distance. Firstly two problems in using a hybrid signal covariance matrix determinant as a frequency point selection standard are analyzed and a settlement solution is provided. A preliminary selecting solution is provided for selecting some frequency points for performing frequency domain ICA and ordering, and then finally selected frequency points and unselected frequency points are determined through frequency point screening. Furthermore an amplitude uncertainty problem is settled on the selected frequency points for finishing separation. The unselected frequency points are separated by means of a separating matrix which is established by means of a relative mixing parameter that is extracted by a separating matrix on the selected frequency points. The frequency points with relatively high separating performance can be selected through the preliminary selecting solution and a frequency point screening solution secondary selecting process. A separating algorithm for the unselected frequency points has advantages of no limitation by microphone distance, capability of restricting the frequency points for extracting the relative mixing parameter in a frequency range without space overlapping, and no influence of an amplitude uncertainty problem to a relative damping parameter.

The invention relates to a method (2) for operating a hearing aid (4), wherein a first input signal (12) is generated from a sound signal (10) by a first input converter (6), wherein a second input converter (8) generating a second input signal (14) from the sound signal, wherein a first angle and an angle range are preset wherein an attenuation directional signal (28) is formed according to the frequency band by means of the first input signal, the second input signal and the first angle, which having a relative attenuation at least for a second angle in an angular range around the first angle, and thereby determining superposition parameters, by means of the first and second input signals and the superposition parameters and / or the second angle forming an amplified directional signal ( 34) having relative amplification for a second angle, generating an angled directional signal (40) from the attenuated directional signal and the amplified directional signal, and generating an output signal (50) with the angled directional signal.