Abstract: A MMIC for providing a suspended transmission medium, comprising a MMIC chip, an upper ground plane overlying and spaced from critical circuitry and a lower ground plane underlying and spaced from the critical circuitry. The upper and lower ground planes are spaced from the critical circuitry at electrically similar distances. The portion of the MMIC chip that has the critical circuitry is suspended over a recess in the housing floor.

Abstract: An RF power detector (10) includes an RF detector circuit (12), a nonlinear feedback amplifier (14), a temperature compensation circuit (16) and a linear feedback amplifier circuit (18). The RF detector circuit converts an RF signal to a voltage representative of the RF signals power level. Nonlinear feedback amplifier (14) nonlinearly amplifies the voltage and compensates for the nonlinearities of the RF detector circuits detector elements. Temperature compensation element provides a temperature compensation signal to compensate for the temperature effects of the detector elements of RF detector circuit (12). The output signal of RF power detector (10) is a substantially linearly representation of the RF input signals power level. Nonlinear feedback amplifier (14) includes a nonlinear feedback circuit (30) with a nonlinear feedback element (32) in the feedback path of op-amp (42).

Abstract: An integrated microstrip (14) to suspended stripline (24) transition structure and method for fabricating the same provide a transition from microstrip (14) to suspended stripline (24) transmission line with minimal electrical discontinuity and insensitivity due to misalignment. A conductor (10) has a constant width, while gradually tapering voids (44,42) in ground planes (36, 38) provide a suspended stripline (24) transmission medium. The gradually tapering voids (44, 42) provide impedance transformation and minimize discontinuities during transition due to fabrication tolerances.

Abstract: An extremely broad band high power termination (10) for microwave and millimeter frequency amplifiers combines a standard resistive low frequency termination (15) with a broad band high frequency absorptive element (13) using an absorptive material such as Eccosorb. A mid-band matching network (14) is provided between the resistive termination (15) and the Eccosorb absorptive element (13). The Eccosorb absorbs the energy of the higher microwave frequencies while the resistor absorbs energy at low frequencies. Accordingly, a much higher power handling capability in a compact planer environment is achieved. This termination (10) is suitable use for use in K-band power amplifier combiners (30) that require high isolation and high power handling capability of the isolated ports (35).

Abstract: A method (140) for tuning millimeter-wave FET amplifiers (20) during manufacture, through the application (144) of a gate bias voltage (52) so as to tune the FET (22) of the amplifier (20) to match an input circuit (24), and through the application (146) of a drain bias voltage (74) so as to tune the FET (22) of the amplifier (20) to match an output circuit (26), then measuring (150) the frequency response of the amplifier (20). This tuning method (140) is repeated (152) until a predetermined frequency response has been achieved. Once achieved, the predetermined frequency response is realized (154) by permanently fixing the gate bias voltage (52) and the drain bias voltage (74) at the determined values. This iterative method (140) of tuning amplifiers (20) is then repeated for all amplifiers (20) to be tuned.

Abstract: A system (10) and method delivers geolocation or other signals (26, 28) to a communication unit (24) located within an area (20) (e.g., a building) where an obstruction exists between the signal transmitter (12, 18) and the communication unit (24). The system (10) uses an infrastructure transceiver apparatus (14, 16, 22) to receive (204, 304, 604) the signals (26, 28) and retransmit (208, 310, 610) them within the area (20). A communication unit (24) calculates responsive data, such as its approximate position, from the retransmitted signals and reports (406, 704) the responsive data to a host system via the infrastructure transceiver apparatus (14, 16, 22).

Abstract: A system (10) and method delivers simplex signals (26, 28) to a communication unit (24) located within an area (20) (e.g., a building) where an obstruction exists between the signal transmitter (12, 18) and the communication unit (24). The system (10) uses an infrastructure retransmission apparatus (14, 16, 22) to receive (204, 304, 402, 404) the signals (26, 28) and retransmit (208, 310, 410) them within the area (20). Geolocation signals (26) from navigation satellites (12) can be retransmitted (208, 310) using the infrastructure retransmission apparatus (14, 16, 22), thus enabling a communication unit (24) located within an obstructed area (20) to calculate its position.

Abstract: A power amplifier (10) suitable for satellite cellular communication systems provides highly efficient linear amplification of noise-like RF signals that have multiple carriers spread over a large instantaneous bandwidth. The amount of distortion present in the output is detected (14, 16, 18) and a feedback signal is provided to control the bias point of the active devices. As drive levels increase, the increased harmonic distortion power detected causes the power amplifier bias to increase thus reducing distortion. The control circuit (20) continually re-biases the power amplifier (12) for maximum efficiency for a predetermined level of distortion. The control circuit (20) may be adjusted to maximize efficiency while maintaining an allowable distortion level over the entire dynamic range of the devices.

Abstract: A MMIC power amplifier (100) uses MMIC FET cells (104, 112) and provides high gain at microwave and millimeter-wave frequencies. The power amplifier includes an input matching network (102), a first plurality of unit FET cells (104) for amplifying in-phase signals provided by the input matching network, a second plurality of unit FET cells (112), an interstage matching network (106) for combining output signals provided by the first plurality of unit FET cells, and providing in-phase signals to the second plurality of unit FET cells; and a combiner (113) for combining output signals of the second plurality of unit FET cells to provide an output signal. The FET cells are designed to be unconditionally stable without the use of an external series gate resistance. The FET cells are combined to provide total device periphery suitable for output power levels exceeding 0.8 watt at frequencies ranging from 19 to 23.5 GHz. The FET cells are designed using device scaling and device modeling techniques.