Microwave and millmeter-wave system components are fabricated by using slotlines extending from the periphery of CPW resonators This technique permits the degree of electrical coupling between the CPW and and the slotlines to be adjusted for matching, and the CPW resonators and slotlines behave as if they were relatively independent circuit elements, permitting transmission line models to be useful design tools and predicting the behavior of the system components The system components are fully planar and allow easy integration of active and passive semiconductor devices in series with the CPW, and in shunt across the slotlines in hybrid and monolithic circuit forms This technique also enables the conductive plane to be split for biasing semiconductor devices coupled to the CPW resonators for microwave and millimeter-wave power generation, tuning, mixing, filtering, frequency multiplication and switching Integration with a notch antenna and slot-to-microstrip transitions are also described which permit a direct radiation/reception or a coaxial connector output

Planar active endfire radiating elements and coplanar waveguide filters with wide electronic tuning bandwidth

A programmable crystal oscillator is provided having a memory for storing frequency-defining parameters. Typically, one of these parameters is used to program an adjustable capacitive load circuit coupled to a crystal to thereby adjust the crystal source frequency. Additional parameters are used to program the output frequency of a phase locked loop circuit coupled to receive the adjusted source frequency. A further parameter can also be used to divide the output frequency of the phase locked loop circuit to supply a specified output frequency. The oscillators can be manufactured as generic programmable crystal oscillators without regard for output frequency and then quickly programmed to produce customer-specified output frequencies with a high degree of accuracy.

Crystal oscillator programmable with frequency-defining parameters

An on-chip apparatus and method are provided for automatically tuning a continuous time filter in which a single filter selectively filters an information signal or, when tuning is desired, an unfiltered reference signal. During tuning, a controller determines the amplitudes of the unfiltered and filtered reference signals and their ratio. From the ratio, the controller ascertains a corresponding center or tuned frequency of the filter. If the ascertained frequency does not substantially equal a desired tuned frequency, the controller directs a bias controller to adjust the bias of the filter until the tuned frequency is substantially equal to the desired tuned frequency.

On-chip self-tuning filter system

Filter adjustment apparatus for adjusting cut-off frequencies or dip frequencies, for example, may be adjusted to desired optimum properties, during application of an input signal of a constant frequency. The optimum filter adjustment data are found, based on data manifested when the level detected output of the filter output crosses a prescribed reference level whereby the filter adjustment operation is simplified and accuracy is improved with a simplified structure, and it is possible to achieve automatic adjustment of the filter characteristics.

Filter adjustment apparatus and method

A worldwide logistics network includes a processing center for receiving customer orders for crystal oscillators over communications links, processing the orders, and generating work orders that are selectively disseminated over communications links to programming centers at strategic locations around the world. Each of the programming centers carries an inventory of generic programmable crystal oscillators. Upon receipt of a work order, a programming center withdraws quantity of programmable crystal oscillators from inventory sufficient to fill the customer order, and, using automated parts handling equipment, the oscillators are successively directed to an interface position with a computer. There, the unique crystal frequency of each oscillator is read and each oscillator is uniquely programmed on the basis of its crystal frequency to generate an output frequency meeting customer specification. Upon completion of this final manufacturing step, the programmed crystal oscillators are shipped to the customers directly from the programming centers.

Worldwide marketing logistics network including strategically located centers for frequency programming crystal oscillators to customer specification

A self-tuning filter is provided through the employment of a voltage tunable filter circuit which simulates a series resistor-inductor-capacitor (RLC) circuit and which is tunable to vary or adjust its resonant frequency in response to the value of an input control voltage. The filter is made self-tuning through the provision of suitable circuitry, responsive to simulated inductance and capacitance voltages, to generate the input control voltage and hence render the voltage tunable filter circuit resonant at the frequency of an applied input signal.

Self-tuning filter

A voltage controlled oscillator for producing an output signal having a frequency proportional to the magnitude of an input control signal includes a tunable filter circuit for simulating a resistance-inductance-capacitance (RLC) circuit with a resonant frequency approximately equal to the base or center frequency around which the voltage controlled oscillator is to operate. Through appropriate feedback means and multiple gain paths within the simulated RLC circuit, there is provided an output signal whose frequency is a function of the input control signal.

Voltage controlled oscillator using a voltage tunable filter with feedback

An electronic filter circuit comprised of summing circuits and integrating circuits is interconnected such that the filter may use the same components to serve either as a band-reject or a band-pass filter having the same natural frequency. Changing of the filter operation between the two modes is accomplished simply by the interchange of two component values.

Active filter with inverse option

IN RECENT YEARS the analog computer has become available to a large number of design and development engineers. It is not difficult for an engineer to become proficient in the use of the analog computer, but one problem which confronts all who use it is that of scaling: How many volts represent one inch? Three popular scaling methods are: (1) the ?actual equation-machine equation method,?1?2 (2) the ?per-unit method,? and (3) the ?direct analogy method.? The first method is better suited to the mathematician than to the engineer because it deals with equations of the system being studied. The system equations are rewritten in terms of computer voltages and are then called ?machine equations.? This tends to cause the engineer to think in terms of the computer rather than to retain a physical picture of the actual equipment he is developing. The other two methods are better in this respect since the thinking tends to be more in terms of actual physical variables. However, when using either of these two methods, many engineers feel that the tie between actual and computer variables is not firm or concrete and that the probability of making a mistake is high enough to introduce uncertainty, especially when integrators or differentiators are involved.

http://ieeexplore.ieee.org/iel5/6366379/6367322/06367326.pdf

A method of scaling and checking computer circuits

A frequency to voltage transducer for producing an output signal having a value proportional to the magnitude of the frequency of an input signal includes a tunable filter circuit for simulating a resistance - inductance - capacitance (RLC) circuit with a resonant frequency approximately equal to the anticipated base frequency of the input signal. Through appropriate feedback means and multiple gain paths within the simulated RLC circuit, there is provided an output signal which is proportional in magnitude to the frequency of the input signal.

L. Jubin Lane

Papers

Self-tuning filter

Voltage controlled oscillator using a voltage tunable filter with feedback

Active filter with inverse option

A method of scaling and checking computer circuits

Frequency to voltage transducer