Abstract: An oscillator having a desired output frequency, comprising a cavity resonator 102 loaded with an anisotropic dielectric material and an oscillator circuit 100 including the cavity resonator 102 as a frequency determining element, the oscillator circuit 100 arranged to operate the cavity resonator 102 at a first frequency in a first mode and at a second frequency in a second mode, the first mode and the second mode each being influenced to a different extent by the thermal coefficient of permittivity of at least one crystal axis of the dielectric material, the oscillator circuit arranged to produce the desired operating frequency from the first frequency and the second frequency. The first frequency and the second frequency differ by an amount corresponding to the desired output frequency.

Abstract: An exemplary embodiment of the present invention described and shown in the specification and drawings is a transceiver with a receiver, a transmitter, a local oscillator (LO) generator, a controller, and a self-testing unit. All of these components can be packaged for integration into a single IC including components such as filters and inductors. The controller for adaptive programming and calibration of the receiver, transmitter and LO generator. The self-testing unit generates is used to determine the gain, frequency characteristics, selectivity, noise floor, and distortion behavior of the receiver, transmitter and LO generator. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or the meaning of the claims.

Abstract: An exemplary embodiment of the present invention described and shown in the specification and drawings is a transceiver with a receiver, a transmitter, a local oscillator (LO) generator, a controller, and a self-testing unit. All of these components can be packaged for integration into a single IC including components such as filters and inductors. The controller for adaptive programming and calibration of the receiver, transmitter and LO generator. The self-testing unit generates is used to determine the gain, frequency characteristics, selectivity, noise floor, and distortion behavior of the receiver, transmitter and LO generator. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or the meaning of the claims.

Abstract: A system and method for generating a local oscillator (LO) frequency in a zero intermediate frequency (IF) receiver or transmitter is presented. A signal is received from a voltage controlled oscillator (VCO). The signal has a VCO frequency. The VCO frequency is divided by a number N to produce a signal having a divided-down frequency. The signal having the VCO frequency is then mixed with the signal having the divided-down frequency to produce an output signal having an output frequency. Local oscillator leakage is reduced. Thus, the receiver or transmitter may operate in multiple wireless communication bands and modes and meet the associated specifications.

Abstract: A transmit frequency is generated for a transceiver by a controllable oscillator which generates an oscillator frequency, a divider by a factor N, and a mixer stage with a subsequent band filter. Signals with the oscillator frequency and the oscillator frequency divided by the factor N are to the mixer stage to generate an output signal at the transmit frequency.

Abstract: An apparatus for detecting a difference between frequencies includes a beat waveform generator which generates a beat waveform signal having a frequency which is equal to a difference between frequencies of a reference clock signal and a target clock signal. A frequency divider divides the reference clock signal by N, where N is an integer, to generate a divided reference-clock signal. A frequency comparator compares frequencies of the beat waveform signal and the divided reference-clock signal, and generates a step out alarm signal which is a binary signal depending upon a polarity of a difference between the frequencies of the beat waveform signal and the divided reference-clock signal.

Abstract: In a high-frequency module according to the present invention in which a conductive cap for an electromagnetic purpose is placed on a substrate on which a plurality of electrical components are mounted by soldering, an insulating adhesive is applied between the plurality of electrical components. Since the insulating adhesive is applied between the electrical components on the substrate, it is possible to prevent such deficiencies as “solder touch” between components due to self-alignment which is caused by a solder which melts in the reflow process. As a result, a highly reliable high-frequency module can be obtained, and the number of application points of the insulating adhesive can be reduced.

Abstract: A microwave synthesizer includes a drift-cancel loop having a narrow-band input, a low-frequency comb input, a wide-band input, and an output for providing an adjustable-frequency output signal. A narrow-band synthesizer is coupled to the narrow-band input, and a comb generator is coupled to the low-frequency comb input. Instead of using a wide-band synthesizer to drive the wide-band input, as conventional topologies have done, the instant invention employs a highly stable, low noise high frequency oscillator. The output of the oscillator is mixed with the output of the comb generator to produce low-noise, high frequency combs. The low-noise, high frequency combs are then used to drive the wide-band input of the drift-cancel loop. Significant reductions in phase noise can be achieved as compared with conventional designs.

Abstract: A system and method for generating a local oscillator (LO) frequency in a zero intermediate frequency (IF) receiver or transmitter is presented. A signal is received from a voltage controlled oscillator (VCO). The signal has a VCO frequency. The VCO frequency is divided by a number N to produce a signal having a divided-down frequency. The signal having the VCO frequency is then mixed with the signal having the divided-down frequency to produce an output signal having an output frequency. Local oscillator leakage is reduced. Thus, the receiver or transmitter may operate in multiple wireless communication bands and modes and meet the associated specifications.

Abstract: A voltage controlled oscillation device includes a voltage controlled oscillator, fixed-frequency oscillator, frequency mixer, and frequency selector. The voltage controlled oscillator changes the output signal frequency in the microwave band in accordance with the input voltage of a frequency control signal. The fixed-frequency oscillator has a fixed oscillation frequency higher than that of the voltage controlled oscillator. The frequency mixer mixes the output signal from the fixed-frequency oscillator and the output signal from the voltage controlled oscillator and outputs the sum frequency and difference frequency between the two signals. The frequency selector selects and outputs one of the sum frequency and difference frequency contained in the output signal from the frequency mixer.

Abstract: An oscillator circuit is disclosed which includes an oscillator to generate a first signal having a first frequency, a second oscillation source to generate a second signal having a second frequency, the second oscillator comprising a frequency divider coupled to the oscillator, and a mixer to mix to the first and second signals, wherein the oscillator, frequency divider and mixer are each quadrature. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or the meaning of the claims.

Abstract: Interference in a receiver caused by a beat frequency arising from mutual interference of local oscillation signals from other, proximately located receivers is prevented by changing over between an externally supplied clock signal and internal clock signal. The selected clock signal is used as the local oscillation signal of the receiver, thereby removing a difference between the mutually interfering local oscillation signals and preventing the beat interference from arising.

Abstract: A stabilised voltage controlled oscillator circuit comprises a closed loop circuit containing a voltage controlled oscillator (34), a local oscillator (40) and a harmonic mixer (38) that mixes a stabilised local oscillator (LO) frequency signal and a radio frequency (RF) signal from the voltage controlled oscillator (34) to obtain an intermediate frequency (IF) signal. An IF amplifier (42) is connected to a linear frequency discriminator (44) that provides an output signal to a summing amplifier (46), which is connected to the voltage controlled oscillator (34). The closed loop circuit uses the linear frequency discriminator (44) to provide a feedback signal that stabilises the voltage controlled oscillator (34).

Abstract: An apparatus and method for synthesizing low-noise, high stability, multi-frequency microwave signals is disclosed. The output frequencies of a lower frequency, low-noise, synthesizer are upconverted to higher microwave frequencies by mixing these frequencies with the output frequency of an ultra low noise microwave oscillator, determined by a very high Q resonator. Such resonators exhibit large frequency dependence on temperature, but the frequency of an ultra low noise microwave oscillator cannot be stabilized by phase-lock to a stable reference because of its very narrow voltage-controlled frequency tuning range, caused by the very high Q of the resonator. The microwave synthesizer output frequency stabilization is achieved by a novel phase-lock loop which uses the frequency tunability of a low noise SAW oscillator to compensate for the frequency drift of the microwave oscillator.

Abstract: An optically controlled MESFET semiconductor oscillator assembly having a MESFET semiconductor which, when voltage biased by a pulsed dc voltage, oscillates at a free running frequency; an optical signal delivery system, such as a light intensity modulator connected to optical fibers; and other oscillator circuitry including a pulse generator. In operation, the pulsed free running oscillation of the MESFET semiconductor can be injection locked to the intensity modulated optical signal delivered via the optical signal delivery system.

Abstract: A frequency synthesizer using a fixed oscillator driving a comb line generator to generate a spectrum of comb lines, one of which is selected by a switched array of fixed-tuned, YIG passband filters. The selected comb line is combined in a mixer with a signal from a local oscillator, which, preferably, is a direct digital synthesizer. The output of the mixer is fed to another switched array of fixed-tuned YIG passband filters where only the desired sideband is selected and the comb line and the other sideband is filtered out. In various alternative embodiments, tunable YIG filters are substituted for each array. Some embodiments also use a reverse slope equalizer to break up the coherent energy in the comb line spectrum at the output of the comb line generator to allow RF amplification to be applied without saturating the amplifier.

Abstract: Apparatus and a method for generating all of the assignable carrier frequencies in the FM broadcast band and for frequency modulating the generated carriers includes a generator of a train of pulses having a crystal-controlled repetition frequency and a specific pulse shape which together produce a spectrum of odd harmonics of the pulse repetition frequency whose separation in frequency is identical to that of the assignable carrier frequencies. This pulse train is then mixed with a 98.0 MHz sine wave to translate the spectrum to the FM band. Simultaneous modulation of all the carriers is achieved by frequency modulating the 98.0 MHz sine wave, whereby the same modulation is imparted simultaneously to all of the carriers.

Abstract: A microwave oscillator circuit is provided for decreasing the number of passive elements such as inductance, etc. in microwave oscillators and frequency doublers. A microwave oscillator circuit is connected to a resonator circuit generating a signal at a frequency f, and produces at its output a signal of frequency nf, and comprises a first field effect transistor having a gate connected to the resonator circuit, a second field effect transistor whose source/drain path is connected in series with the source/drain path of the first field effect transistor and a connecting circuit for coupling either the gate or source of the first field effect transistor to the gate of the second field effect transistor. A signal of frequency nf is output at a node corresponding to a connection point between the source of the first field effect transistor and the drain of the second field effect transistor.

Abstract: A multimode oscillator is disclosed which employs a single gain loop for exciting at least two modes of a resonator to cause the oscillator to oscillate simultaneously at at least two frequencies. The multimode oscillator comprises the resonator, an amplifier to provide gain at the appropriate operating frequencies to support simultaneous oscillation at such frequencies and an equalizing network with amplitude and phase characteristics versus frequency to support the simultaneous modes of oscillation. The single loop oscillator permits separate control of the two simultaneous different frequencies of oscillation. In order to minimize thermal hysteresis, at least the active portion of the feedback loop does not include inductors. In some applications, the multimode oscillator may include one or more rejection networks to suppress unwanted oscillations. The useful outputs of the multimode oscillator are one or more of the operating frequencies, harmonics and intermodulation products.

Abstract: Generation of multiple, harmonically related frequency outputs is achieved using a digital asymmetrical harmonic waveform generator, such as a high speed digital frequency divider, for example. The digital frequency divider is used with a division ratio that provides a nonsymmetrical waveform that generates a fundamental and odd and even harmonics of the fundamental derived from a reference frequency signal. The harmonically related frequency outputs from the digital frequency divider may be buffered, filtered, and mixed with the reference frequency signal to obtain a series of clean, single frequency tones suitable for use as frequency conversion local oscillator signals. The result is a small, low power, low cost multiple frequency tone generator.

Abstract: A differential mixer oscillator employing two transistors in a differential pair as the sustaining amplifier for a quartz crystal resonator at some first high frequency. The bias current of the differential pair is modulated at a second high frequency derived from some second frequency generating source, typically a second quartz crystal resonator, and the product terms are available at the collectors of the two transistors for selective filtering. The differential mixer oscillator may be employed in multiples, and with a variety of current sources, such as a Colpitts oscillator circuit.

Abstract: A multimode oscillator is disclosed which employs a single gain feedback loop for exciting at least two modes of a resonator to cause the oscillator to oscillate simultaneously at at least two frequencies. The multi-mode oscillator comprises the resonator, an amplifier to provide gain at the appropriate operating frequencies to support simultaneous oscillation at such frequencies and an equalizing network with amplitude and phase characteristics versus frequency to support the simultaneous modes of oscillation. The single loop oscillator permits separate control of the two simultaneous different frequencies of oscillation. In order to minimize thermal hysteresis, at least the active portion of the feedback loop does not include inductors. In some applications, the multimode oscillator may include one or more rejection networks to suppress unwanted oscillations. The useful outputs of the multimode oscillator are one or more of the operating frequencies, harmonics and intermodulation products.

Abstract: An apparatus and method is disclosed which phase locks a frequency-agile modulated output signal to any selected channel of a comb generated output. The phase error of an input signal is tracked, the input signal is modulated up to a carrier output frequency, and the modulated output frequency is locked to the comb generator output by subtracting the input signal and negating the phase error.

Abstract: A frequency divider is disclosed that includes two bipolar transistors coupled as a Darlington pair, where the base of the first transistor receives an input signal to be divided, and where the common collectors of the transistors generate an output signal having a frequency equal to one-half or other integer submultiple of the input signal. The frequency divider also includes a feedback network operable for coupling a portion of the output signal from the output side of the transistors to the input side of the transistors. Such a frequency divider can provide signal conversion gain at microwave frequencies.

Abstract: A self-oscillating mixer is disclosed, and includes two bipolar transistors coupled as a Darlington pair, where the base of the first transistor receives an input signal, and where the common collectors of the transistors generate an output signal; and a feedback resonator operable for coupling signals at the local-oscillator frequency from the output side of the transistors to the input side of the transistors. Such a self-oscillating mixer can provide signal conversion gain at microwave frequencies.

Abstract: The output signal frequencies of two current controlled oscillators are made to track closely by matching timing currents with a current mirror. A frequency difference between the output signals is obtained by establishing an additional timing current for only one of said oscillators.

Abstract: An inductive pressure sensor is proposed which has at least one coil embodying a frequency-determining part of an oscillator and disposed at a distance from a diaphragm which is deflectable in accordance with pressure. When pressure is exerted on the diaphragm, the inductance of the coil and thus the oscillator frequency are shifted. The coil is a flat, spiral element and the diaphragm has a surface of highly conductive or ferrite material. It is further provided that two oscillators of identical design and having corresponding coils are used, operating under identical thermal conditions. Either one oscillator operates at a fixed frequency, so that both absolute-pressure measurements and differential-pressure measurements relative to ambient pressure can be made, or else the two oscillators can be detunable in accordance with pressure, so that differential-pressure measurements between two media can be made. The output signal is then obtained by mixing.

Abstract: The optical injection-locking of an FET oscillator is accomplished by injecting the beat signal between two coherently mixed slave lasers, which are locked to different harmonics of a modulated master laser, into the FET oscillator to be locked. 120 GHz injection-locking beat signals are possible using this technique.

Abstract: The oscillator circuit comprises a digital temperature compensation circuit connected to a low and a high frequency quartz oscillator. The two quartz oscillators have the same inversion temperature points and a different temperature behaviour.In the temperature compensation circuit a beat frequency is produced between the divided signal of the high frequency oscillator and the frequency of the low frequency oscillator and then fed to a correction circuit and multiplied therein with a correction factor which has been stored in a PROM. The obtained correction signal is fed into the frequency divider chain for obtaining a temperature compensated outgoing signal for use in a timer circuit.The temperature compensation circuit is simply designed and allows high accuracy, which is particularly well suited for a wristwatch or a photo camera.

Abstract: An oscillator circuit having a digital temperature compensation circuit which contains two low frequency quartz oscillators, a beat frequency generator and a correction circuit and a logic circuit selectively controlling an addition circuit. The beat frequency generator receives the frequencies generated by the low frequency oscillators. The difference between the low frequencies is fed into the correction circuit which in turn cooperates with the logic circuit. The beat frequency generator is controlled by a high frequency oscillator having an integrated RC circuit and the correction circuit has a PROM in which the correction functions are stored. The selectively controlled addition circuit acts on the output signal of the first oscillator and corrects the frequency thereof.

Abstract: A signal generator having a digital temperature compensation circuit contains high and low frequency quartz oscillators (HF and NF), the low frequency oscillator being used for temperature compensation. Both oscillators are manufactured such that the descending portion of the temperature dependent parabolic frequency curve of the low frequency oscillator passes through the temperature inversion point of the parabola of the high frequency oscillator.The frequencies of both oscillators are first adjusted such that the ratio thereof is inversely proportional to the ratio of the parabolic temperature coefficient, i.e., f.sub.1 :f.sub.2 =.beta..sub.2 :.beta..sub.1. Subsequently two substantially identical reference frequencies are adjusted and, by feeding back the output frequency, combined in such a manner that an output frequency independent of temperature is produced which is determined substantially by the high frequency oscillator.

Abstract: A signal generator includes a high frequency oscillator such as a quartz crystal oscillator at a frequency of 4.19 MHz, a low frequency quartz oscillator with a frequency of 32 kHz, a beat frequency generator for producing a correction signal which is transmitted to a programmable frequency divider, and an electronic switch for periodic switching of the high frequency quartz oscillator. By periodically switching-on the high frequency quartz oscillator, comparing its frequency curve with that of the low frequency quartz oscillator and and appropriately adjusting the programmable frequency divider, the advantages of long term stability, temperature of behavior and aging of a high frequency oscillator are combined with the low current consumption characteristics associated with the low frequency quartz oscillator, whereby the life of a battery powering the signal generator can be substantially extended.

Abstract: An arrangement for temperature compensating transducers including two elastic surface wave oscillators whose frequencies are mixed to produce an output frequency that is a function of a parameter to be measured such as force, pressure or acceleration. A delay element such as a transmission line having a delay that is a function of temperature is inserted into the loop of at least one of the oscillators to balance oscillator frequency deviations resulting from temperature changes.

Abstract: An improved metal detecting device of the beat frequency oscillator type is provided which incorporates a method for determining the side of the zero beat frequency at which a search oscillator is operating. The device includes a search coil conveniently mounted which is part of a search oscillator. A reference oscillator is also provided, the output of which is digitally compared to that of the search oscillator by a digital phase comparator. The digital phase comparator output is applied through a low pass filter to a slope detector circuit. The slope detector output signal is supplied to both an audio output circuit and a filter/comparator. The audio output is sufficient to facilitate location of permeable and conductive substances. The output of the slope detector also contains information which is extracted by the filter/comparator and translated to an audible signal by an oscillator and the audio output circuit.

Abstract: A method and means for translating frequencies, as for example, to correct a frequency error .DELTA.f.sub.d introduced into a carrier signal of frequency f.sub.c, comprising means for dividing the resultant signal frequency (f.sub.c +.DELTA.f.sub.d) by N, resulting in a divided-down frequency (f.sub.c /N+.DELTA.f.sub.d /N), with .DELTA.f.sub.d being reduced to .DELTA.f.sub.d /N, and then heterodyning the divided-down frequency with signal of frequency (f.sub.c +f.sub.c /N) to produce a resultant signal of frequency (f.sub.c +.DELTA.f.sub.d /N), the frequency error remaining at its low, divided level .DELTA.f.sub.d /N.

Abstract: An octave conversion system of the fundamental frequency of an audible tone signal produced by electrically picking up mechanical vibration of a musical instrument in which the audible tone signal and an audible modulation signal having a frequency in a preselected relation to the fundamental frequency of the tone signal are applied to a multiplier which is preferably constituted by a voltage-controlled amplifier. When the modulation signal has a frequency half that of the tone signal, the tone signal is one-octave down-converted, while, when the modulation frequency is equal to the tone signal frequency the tone signal is one-octave up-converted. With this frequency conversion system the fundamental wave component of the octave-converted tone signal has the same envelope as that of the original tone signal. This frequency conversion system is advantageous in attaining small size versions of electric musical instruments and extension of inherent compasses of electric musical instruments.

Abstract: An oscillator circuit comprising a transistor, a piezoelectric element and a D.C. source, such as a battery, said transistor being common collector mounted and said piezoelectric element being disposed between the base of said transistor and a first terminal of said D.C. source, characterized in that it is adapted so that the response of said oscillator is ensured by a capacitive impedance comprising exclusively the capacitance of the base-emitter junction of the transistor, the voltage of the source being at most equal to 1.5V.

Abstract: A frequency synthesizer, responsive to a reference signal having a frequency f.sub.r, for supplying an output signal at a frequency selectable from M times N signal frequencies (where M and N are preselected integers) is disclosed. In each disclosed arrangement, a set of M signals that are each harmonically related to f.sub.r is derived by a cascade connected harmonic generator and comb filter, and a set of M signals that are each harmonically related to f.sub.r /M is derived from the reference signal by a cascaded frequency divider, harmonic generator and comb filter. Each of these signal frequencies within the two sets of signals can be selectively coupled to the input ports of signal mixing apparatus and bandpass filtering is employed to couple either the mixer sum or difference frequency to the synthesizer output terminal. In some situations, a single mixer circuit and bandpass filter is employed.