Abstract: Methods, systems, and devices for determining a parameter of interest of downhole fluid using an acoustic assembly comprising a single solid acoustic transmission medium having a face immersed in the downhole fluid. Methods include using characteristics of a plurality of acoustic pulse reflections from a solid-liquid interface at the face of the solid acoustic transmission medium to estimate the parameter of interest in near real-time. The characteristics may comprise a corresponding reflection amplitude and the corresponding unique angle of reflection for each acoustic pulse reflection. Methods may include generating a two dimensional data set from measured characteristics, generating a curve by performing data fitting on the two dimensional data set, and using the reciprocal slope of the curve to estimate the parameter of interest.

Abstract: A selective frequency limiter having a magnetic material and a slow wave structure disposed to magnetically couple a magnetic field, produced by electromagnetic energy propagating through the slow wave structure, into the magnetic material.

Abstract: A tunable acoustic resonator device has a piezoelectric medium as a first thin film layer and a tunable crystal medium as a second thin film layer. The tunable crystal medium has a first acoustic behavior over an operating temperature range under a condition of relatively low applied stress and a second acoustic behavior under a condition of relatively high applied stress. The acoustic behaviors are substantially different and, consequently, the different levels of applied stress are used to tune the acoustic resonator device. Compared with the tunable resonator device consisting of only tunable crystal medium, a device having both the piezoelectric and tunable crystal medium has advantages such as larger inherent bandwidth and less nonlinearity with AC signals. The device also requires a smaller applied stress (i.e. bias voltage) to achieve the required frequency tuning.

Abstract: A group delay adjusting circuit. The group delay adjusting circuit comprises an electronically adjustable variable capacitance, and an electronically variable virtual inductor coupled in parallel to the electronically variable capacitance at a node.

Abstract: A group delay adjusting circuit. The group delay adjusting circuit comprises an electronically adjustable variable capacitance, and an electronically variable virtual inductor coupled in parallel to the electronically variable capacitance at a node.

Abstract: To make a variable phase shifter at low cost and that is easy to manufacture, two propagation paths for a high frequency signal are provided in parallel between the input and the output of the phase shifter. These two paths are of different lengths. An intermediate node on one of the paths is connected to an intermediate node on the other path by a PIN diode. The diode is connected to the paths by a segment of line further enhancing the length difference. By biasing the diode to a desired level, it is caused to present a particular impedance to propagation. It is shown that by acting in this way the diode can vary the phase shift between the input and the output without needing to use harmful reactive components.

Abstract: A phased array radar system employs programmable microelectromechanical (MEM) switches and transmission lines to provide true time delays or phase shifts in order to steer the array beam. The array includes an excitation signal source, a power division network for dividing the excitation signal into a plurality of excitation signal components, a plurality of programmable time delay/phase shift circuits including the transmission lines and MEM switches, and a plurality of radiating elements. An adaptive controller provides the control signals to set the MEM switches and select the time delay/phase shift through each time delay/phase shift circuit, thereby steering the array beam to a desired direction.

Abstract: An acoustic device has an acoustic wave propagating medium exhibiting elastic abnormality in the vicinity of a Curie temperature. It is desirable that such an acoustic wave propagating medium be formed of a ferroelectric substance or a high-elastic substance and, in particular, have a Curie temperature at normal temperatures. For example, such ferroelectric substance is a solid solution expressed by Cs(Pb.sub.1-x Sr.sub.x)(Cl.sub.1-y Br.sub.y).sub.3 or (Bi.sub.1-x Dy.sub.x)VO.sub.4. By changing values of x and y appropriately, the Curie temperature of the solid solution can be varied, and an acoustic wave propagating medium meeting the purpose of use can be obtained. In such an acoustic wave propagating medium, an elastic coefficient C.sup.P at the time of constant polarization differs greatly from an elastic coefficient C.sup.E at the time of a constant electric field in the vicinity of the Curie temperature. Accordingly, the propagation velocity of acoustic waves is greatly different, too.

Abstract: Apparatus and method for compensating for differences in time at which an incoming acoustic wave is received by an array of acoustic signal receivers to take account of the shape of the incoming wave and the non-zero incidence angle of its approach. Each receiver is provided with a time delay module that introduces a large or coarse scale time delay .DELTA.t.sub.L plus a small or fine scale time delay .DELTA.t.sub.S, where .DELTA.t.sub.L is an integral multiple of a coarse scale time interval length .DELTA.t.sub.c and .DELTA.t.sub.S may be varied continuously from 0 to a predetermined time interval length (.DELTA.t.sub.S).sub.max that may be made at least as large as .DELTA.t.sub.c.

Abstract: Apparatus and method to provide a controllable one-dimensional array or two-dimensional array of delay times for an array of acoustic signals propagating in a plurality of bodies of piezoelectric material. Each piezoelectric body is provided with three or more pairs of electrodes, with the first and second electrodes of a pair being spaced apart and positioned on first and second surfaces, respectively, of the piezoelectric body. As an acoustic wave propagates longitudinally in the piezoelectric body, an electrical voltage signal is generated between each electrode pair as the wave passes between the two electrodes of that pair. Time delay is controlled by choice of the longitudinal position of each electrode pair along the piezoelectric body.

Abstract: An ultrasonic delay line device has an adjusting circuit for adjusting delay time provided between two terminals at the power input side of an ultrasonic delay line, wherein the adjusting circuit includes a serial connection of a fixed capacitor and a variable resistor connected between said two terminals of the power input side and a fixed coil connected in parallel with the serial connection of the fixed capacitor and the variable resistor.

Abstract: A delay device for a frequency signal comprises an element made of acousto-optical material, provided with a first piezo-electric transducer transmitting an acoustic signal in the element and with a second piezoelectric transducer capable of detecting an acoustic wave. A light beam goes through the element and creates a field charge in the element. This charge field plays the role of a reflector for the acoustic wave transmitted by the transducer. By translating the beam along the direction Z, the propagation time of the transmitted acoustic wave is made to vary.

Abstract: A reading device operates by the placing in interference of a reference signal, in the form of a fundamental wave train, with delayed wave trains constituting the useful signal. The device comprises an interferometer, a first branch (32) of which is traversed by at least said fundamental wave train (14), the first branch (32) being equipped, with means (37, 67, 87) for the generation of quantified delays of said fundamental wave train (14) with means (39) for the generation of a continuously variable delay of said fundamental wave train (14) over a range about each quantified delay value.

Abstract: A laminar magnetic flux generating apparatus for use with a signal delay line or other apparatus requiring a long, narrow, uniform field. Magnetic flux orthogonal to the primary flux is generated by an array of spaced apart magnets located along the length of the long, narrow, uniform field; combined orthogonal and primary fluxes provide the desired long, narrow, uniform field flux within a magnetically conductive enclosure. Vector summation and fluid analogies for the achieved flux are disclosed.

Abstract: The disclosure relates to a small volume bulk acoustic channelizer, which does not utilize light and thereby avoids the shortcomings of light-related channelizers including limited dynamic range and poor response to short pulses. The device is essentially a bulk acoustic analogue of an optical spectroscope.

Abstract: A cascade combination of magnetostatic delay line elements operating in different signal propagation modes for the purpose of achieving dispersion cancellation; magnetic bias control of the attained frequency-dependent delay and a magnetic bias field establishing apparatus for providing the tubular, laminar magnetic flux needed for backward volume wave operation of a magnetostatic delay element are also included.

Abstract: An oscillator including two magnetostatic wave delay lines of different lengths formed on the surface of a magnetic material, one of whose ends is common and made by a first microstrip coupler, each of the other ends being made of a second and a third microstrip couplers respectively. The two lines are looped by means of a single amplifier. By selecting the two lengths, it is possible to obtain the desired interval between modes in such a way that there is a single oscillation mode comprised in the pass-band of the strips, in a pre-determined tuning band. This oscillator operates in the microwave range.

Abstract: An electric signal transmission transducer employing a ferromagnetic amorphous ribbon and especially an electric signal transmission element and system and an electroacoustic signal conversion system using a ferromagnetic amorphous ribbon. The transmission transducer also provides for applying a magnetic field to the ferromagnetic amorphous ribbon for controlling the electric signal transmission or delay time. Also shown are the electric and magnetic characteristics of ferromagnetic amorphous ribbons after various heat treatments in various magnetic fields.

Abstract: An electroacoustic apparatus is disclosed for providing beam steered and focused compressional or shear waves, using an interdigital generating grid operative with one surface of a piezoelectric delay line member. The generating transducer is provided with electrode elements having a variable spacing determined by the location of a receiving transducer on another surface of the delay line. The electrode elements are energized in a predetermined phase relationship by an input signal. The apparatus is suitable for use to process signals as a pulse compression or pulse expansion dispersive delay line.

Abstract: An apparatus for measuring the amount of relative displacement of mutually facing electrodes in such a direction as to cause a change in the distance therebetween, comprises:a power source generating an AC signal of a determined frequency;a phase-shifting means comprising a resistor and the mutually facing electrodes, the phase-shifting means being adapted to apply the AC signal to the mutually facing electrodes through the resistor and to generate an output signal of which the phase is shifted in response to the amount of relative displacement of the mutually facing electrodes; anda phase difference measuring means for measuring phase difference between the output signal of the phase-shifting means and the AC signal and generating a signal corresponding to the amount of relative displacement of the mutually facing electrodes.

Abstract: A delay line time compressor which can be operated at different multiplicon factors by virtue of changes in the length of the recirculation loop for selected parts of the recirculation routine. A preferred embodiment utilizes an organization of parallel recirculation loops and is well adapted to semiconductor shift register implementation. Another embodiment utilizes a single high frequency delay element such as glass, in combination with a shift register.

Abstract: A variable delay device for delaying an electrical signal includes a bar-shaped magnetostrictive member to be a transmitting path of a supersonic wave, an input transducer for converting an electric signal into a supersonic wave and an output transducer for converting a supersonic wave into an electric signal, the input and output transducers being provided at at opposite end portions of the magnetostrictive member, and a magnetic field producing device provided between the input and output transducers for supplying the magnetostrictive member with a magnetic field which varies in intensity along the elongated direction of the magnetostrictive member. The magnetic field supplied to the magnetostrictive member is controlled by a control signal applied to the magnetic field producing device to vary the Young's modulus of the magnetostrictive member. As a result, the velocity of the supersonic wave being transmitted therein is varied, to thereby control the delay time of the electric signal.