Abstract: Greater levels of microwave and millimeter microwave frequency power is achieved in a new power amplifier structure in which sixteen MMIC amplifiers are supported in a 4×4 row by column matrix and the output (and input) manifold is of a “crazy-H” power combining structure. Even greater output power, on the order of 100 watts at 35 GHz, is achieved by combining multiple numbers of such power amplifier units through a radial combiner.

Abstract: An umbrella-shaped matching network (10, 14, 16) for matching phase and impedance in a power amplifier (2). The matching network (10, 14, 16) employs rounded corners (22). The rounded corners (22) reduce microwave signal scattering losses, because they are less prone to signal radiation than square corner power combining networks. The matching network (10, 14, 16) includes slits (24) defining separated arms (26). The slits (24) are positioned in such a way that they provide phase and amplitude balance for the signal presented to the amplifiers (2). The slits (24) also prevent current from traveling transversely.

Abstract: A field effect transistor with a double sided airbridge comprises a substrate containing a conductive region and source, drain and gate electrodes disposed on the substrate. The gate electrode has a finger portion with a first end secured to the substrate between the source and drain electrodes and a second end, and a double sided airbridge portion flaring outwardly from the second end and having opposed first and second extremities. A first gate pad is disposed on said substrate outwardly from the source electrode and is connected to the first extremity. A second gate pad is disposed on said substrate outwardly from the drain electrodes and is connected to the second extremity. The gate pads serve to support the airbridge gate finger so as to reduce stress on the gate finger. The first and second gate pads receive and transmit signals through the airbridge and to and from the gate finger.

Abstract: This invention discloses an emitter for a vacuum microelectronic device. The emitter includes a heterojunction step-doped barrier comprised of a first gallium arsenide region, an aluminum gallium arsenide region adjacent the first gallium arsenide region, and a second gallium arsenide region adjacent the aluminum gallium region and opposite to the first gallium arsenide region. The first gallium arsenide region includes a layer of heavily doped n-type gallium arsenide. The aluminum gallium arsenide region includes an intrinsic layer and a heavily doped p-type layer. The second gallium arsenide region includes a heavily doped p-type layer adjacent the aluminum gallium arsenide region, an intrinsic layer and a heavily doped n-type layer adjacent a vacuum region. In addition, a graded layer between the first gallium arsenide layer region and the aluminum gallium arsenide region is provided.

Abstract: The spatial power combiner disclosed here is used to efficiently combine the power sources, which incorporate two-terminal negative resistance devices, in a coherent manner such that a high power output with a stable and definite frequency and phase is obtained, the sources to be combined being arranged in an array configuration.