Abstract: A monolithic quasi-optic amplifier is provided for co-linear beam propagation in the millimeter wave frequency range (30-300 GHz). The amplifier comprises a multiplicity of unit cells that act as nearly independent amplifiers. Each unit cell includes a GaAs transistor, a slot antenna, a patch antenna, a microstrip line, and a DC bias provided by a ground plane that routes non-radiating transmission lines without interference. The slot antennas on GaAs provide preferential directionality in receiving the input waves. A vertically polarized input wave couples energy into each unit cell through the slots in the ground plane, through the microstrip lines, and to the base of each transistor. After amplification by the transistors, the signal is fed to the patch antennas, which generate a horizontally polarized output wave. The size of each patch antenna, which is determined by the operating frequency, is approximately 1 mm by 1 mm in GaAs at 44 GHz.

Abstract: A III-V semiconductor device is provided with a ballasting resistor that may be connected in series with the emitter, collector, or base of an HBT, depending on the function of the device. The semiconductor ballasting resistor is formed in the subcollector epitaxial layer that is in intimate thermal contact with the substrate. The resistor is defined by isolating a rectangular area of the subcollector with ohmic contacts at each end and is fabricated with no processing steps in addition to those required for the HBT. The resistor provides self-limiting current capacity because of its semiconductor nature. Connected in series with the HBT emitter, the semiconductor resistor prevents destruction of the HBT, particularly in multiple cell, high power applications.

Abstract: A monolithic integrated circuit provides RF and DC coupling for a unit cell of a high power quasi-optic grid amplifier. The monolithic chip includes two heterojunction bipolar transistors (HBTs) connected in a differential pair configuration with a common emitter and integrated collector-base and emitter bias resistors. Each of the plurality of unit cells comprising the quasi-optic grid amplifier includes an emitter-coupled HBT differential pair chip at the center, an input antenna that extends horizontally in both directions from the two base leads, an output antenna that extends vertically in both directions from the two collector leads, and high inductance bias lines for the emitter and collectors. The grid amplifier, which functions as a high frequency, high gain, wide bandwidth, free-space beam amplifier, comprises a plurality of unit cells arranged in a repeating pattern of input and output dipole antennas.

Abstract: An analog transversal filter includes a charge transfer delay line, including a plurality of cells for storing electrical charge, and a multiphase clock to transfer electrical charge from cell to cell through the delay line. A plurality of injection electrodes are connected to predetermined ones of the cells to sample an electrical signal, weight the signal sample a predetermined amount, and inject a charge packet representing the weighted signal sample into the cell. An output electrode collects and sums the charge packets transferred through the delay line. In another embodiment, the filter includes a plurality of charge transfer delay lines, with a plurality of cells for storing electrical charge in each delay line.