Abstract: A surface mount chip resistor for increasing power handling capabilities of radio frequency (RF) circuits and for minimizing parasitic capacitance and inductance effects, the chip resistor includes a ceramic substrate having a main portion and an outrigger. A resistor element is between an input contact and an output contact on a top surface of the main portion. A ground plane attachment area is on a top surface of the outrigger. The ground plane attachment area is mounted to a ground plane of a circuit board to provide a heat pathway for dissipating heat generated by the resistor element.

Abstract: An integrated coupler may vertically integrate a hybrid coupler and a directional coupler. The hybrid coupler may include a first quarter-wave metallic strip dielectrically coupled to a second quarter-wave strip. The directional coupler may include the second quarter-wave metallic strip dielectrically coupled to a third metallic strip. The first quarter-wave metallic strip may receive a first input signal. The second quarter-wave metallic strip may receive a second input signal, and it may superimpose the first quarter-wave metallic strip along a vertical space, so as to combine power received from the first input signal and the second input signal to form an output signal. The third quarter-wave metallic strip may superimpose the second quarter-wave metallic strip along the vertical space, so as to sample the output signal of the second quarter-wave metallic strip.

Abstract: A surface mount chip resistor for increasing power handling capabilities of radio frequency (RF) circuits and for minimizing parasitic capacitance and inductance effects, the chip resistor includes a ceramic substrate having a main portion and an outrigger. A resistor element is between an input contact and an output contact on a top surface of the main portion. A ground plane attachment area is on a top surface of the outrigger. The ground plane attachment area is mounted to a ground plane of a circuit board to provide a heat pathway for dissipating heat generated by the resistor element.

Abstract: A temperature-dependent attenuator including one or more temperature-dependent resistors disposed in series with a transmission line and an inductive element shunting at least one of the temperature-dependent resistors.

Abstract: The present invention is a wideband directional coupler comprising first and second coupled transmission lines and first and second equalizers connected at opposite ends of the coupled portion of the second transmission line. Illustratively, the first and second equalizers are RC filters. The first and second equalizers are designed to have transmission characteristics that vary with frequency so as to offset the frequency variation of the coupling factor of the coupled transmission lines.

Abstract: A preferred embodiment of the present invention comprises at least first and second thermistors, arranged into a classical Tee, Pi, or Bridged Tee attenuator design, a heating element, a temperature sensor, and a control circuit. The thermistors have different temperature coefficients of resistance and are in close proximity to the heating element and the temperature sensor. The control circuit receives a voltage signal from the temperature sensor, compares that signal with a voltage signal specifying a desired temperature, and applies electrical energy to the heating element until receiving a signal from the temperature sensor that the temperature of the thermistors matches the desired temperature. As a result, the attenuation of the attenuator can be changed at a controlled rate by varying the temperature of the thermistors, while the impedance of the attenuator remains within acceptable levels.

Abstract: A temperature and frequency variable gain attenuator comprises a temperature variable attenuator and a temperature variable filter network whose resistances changed to c generate different responses that vary over temperature and frequency. At least three different thick film thermistors are used, with two of these used on the attenuator and a third one used on the filter network. The temperature coefficients of the thermistors are different and are selected so that the attenuator and filter network attenuation change at a controlled rate with changes in temperature while the impedance of the gain equalizer remains within acceptable levels. Substantially any temperature coefficient of resistance can be created for each resistor by properly selecting and mixing different inks when forming the thick film thermistors. Furthermore, the attenuator can have either a negative temperature coefficient of attenuation or a positive temperature coefficient of attenuation.

Abstract: The present invention is an absorptive-type cable temperature and frequency equalizer that offsets changes in the gain of the other circuit components cables with increases in temperature and/or frequency. The equalizer comprises a temperature variable filter network having component values and a temperature coefficient of resistance that vary over temperature and frequency to produce a desired response. The temperature and frequency equalizer has at least one thick film thermistor connected in series with a quarter wavelength transmission line. The thermistor absorbs forward and reflected signals at lower frequencies.

Abstract: An absorptive temperature-variable microwave attenuator is produced using a first plurality of shunt resistors separated by quarter-wave transmission lines connected by a series resistor with a second plurality of shunt resistors separated by quarter-wave transmission lines. At least one or more of the resistors are temperature-variable resistors. The temperature coefficients of the temperature-variable resistors are selected so that the attenuator changes at a controlled rate with changes in temperature while attenuator remains relatively matched to the transmission line. In one embodiment, the resistors are thick-film resistors and a variety of temperature coefficients can be created for each resistor by properly selecting and mixing different inks when forming the thick film resistors. Furthermore, attenuators can be created having either a negative temperature coefficient of attenuation or a positive temperature coefficient of attenuation.

Abstract: An integrated N-way Wilkinson power divider is described. In one embodiment, the N-way Wilkinson power divider uses a conductor layer with a cross-over (or cross-under) resistor insulated from the conducting layer by an insulating bridge. In one embodiment, the width of the transmission line underneath a cross-over resistor is adjusted to improve performance In one embodiment, a three-way Wilkinson power divider is formed using microstrip transmission lines on a single-layer substrate that supports the microstrip transmission lines, dielectric insulators, and resistors.

Abstract: An absorptive temperature-variable microwave attenuator is produced using at least two temperature-variable (or fixed) resistors in series with a transmission line. The temperature coefficients of the temperature-variable resistors are selected so that the attenuator changes at a controlled rate with changes in temperature while attenuator remains relatively matched to the transmission line. In one embodiment, the resistors are thick-film resistors and a variety of temperature coefficients can be created for each resistor by properly selecting and mixing different inks when forming the resistors. Furthermore, attenuators can be created having either a negative temperature coefficient of attenuation or a positive temperature coefficient of attenuation.