Mark A. Basten

A 100 mW, 0.670 THz power module

A 0.670 THz Power Module based on a vacuum electronic (VE) power amplifier and a solid-state power amplifier (SSPA) has produced >;100 mW, operating from 0.640-0.685 THz in a bread-board demonstration. The driver amplifier is a power-combined, MMIC SSPA module based on InP HEMT technology. The compact VE power amplifier is based on a DRIE-fabricated folded waveguide slow-wave circuit, together with a high current density thermionic cathode and a single-stage, depressed collector for increased overall device efficiency. The VE power amplifier achieved 21.5 dB of gain, 15 GHz of operational bandwidth, a collector efficiency of 93% and an overall device efficiency of 0.44%.

220 GHz power amplifier testing at Northrop Grumman

A 220 GHz power amplifier has been demonstrated as part of the DARPA HiFIVE program. This amplifier is based on a folded waveguide circuit, and operates at 19 kV and 250 mA. Short pulse tests resulted in 56 W at 214 GHz and a 5.0 GHz bandwidth.

1.2: Sub-millimeter and THz power amplifier development at northrop grumman

Vacuum electronic (VE) power amplifiers are being developed between 100 GHz and 1 THz. Minimum power goals are 50 watts at 220 GHz, and 100 mW at 670 GHz. These devices will use advanced, high current density cathodes, a folded waveguide as the slow-wave circuit, and a depressed collector for overall device efficiency. Operation at duty cycles of 50–100% is anticipated.

220 GHz folded waveguide circuits for high power amplifiers

Folded waveguide interaction circuits for a vacuum electronic amplifier have been designed. Microfabrication efforts to produce the FWGs are underway and preliminary analysis of the properties of these slow wave circuits has been completed.

0.850 THz vacuum electronic power amplifier

Northrop Grumman Electronic Systems has developed the first, compact, microfabricated vacuum electronic amplifier operating at 0.835-0.875 THz. The amplifier produced >50 mW of output power at the window at frequencies between 0.835-0.842 THz and 39.4 mW of output power at 0.850 THz. The amplifier exhibited 26 dB of small signal gain and 11 GHz of instantaneous bandwidth. The compact power amplifier is based on a DRIE-fabricated folded waveguide slow-wave circuit, together with a high current density thermionic cathode, a high field permanent magnet solenoid, and a single-stage depressed collector for overall device efficiency.

Testing of a 0.850 THz vacuum electronic power amplifier

A 0.850 THz vacuum electronic power amplifier capable of >50 mIV output power is being tested at Northrop Grumman Electronic Systems. The compact power amplifier is based on a DRIE-fabricated folded waveguide slow-wave circuit, together with a high current density thermionic cathode, a high field permanent magnet solenoid, and a single-stage depressed collector for overall device efficiency. The new 0.850 THz power amplifier design is based on a 0.670 THz source that achieved over 100 mIV of output power with 21.5 dB of saturated gain, 15 GHz of operational bandwidth, a collector efficiency of 93% and an overall device efficiency of 0.44%.

220 GHz power amplifier development at Northrop Grumman

Northrop Grumman Electronic Systems (NGES) is developing compact, efficient sources above 100 GHz as part of the DARPA THz Electronics (THzE) program. The THzE Phase I goal is a high duty amplifier producing 100 mW of RF power at 670 GHz. These devices will use advanced, high current density cathodes, a folded waveguide as the slow-wave circuit, and a depressed collector for overall device efficiency. Operation at duty cycles of 50–100% is anticipated. Realization of fully-integrated high power amplifiers at these frequencies will have a significant impact on a variety of defense applications including covert, high data-rate communication, airborne collision avoidance systems, and high resolution radar imaging.Northrop Grumman Electronic Systems is developing compact, efficient amplifiers above 100 GHz as part of the DARPA High Frequency Integrated Vacuum Electronics (HiFIVE) program. Sub-components are being demonstrated for a compact 100 W amplifier operating at 220 GHz including a low attenuation folded waveguide (FWG) circuit and a high aspect ratio electron beam propagating through a FWG circuit at 95% transmission efficiency. The HiFIVE program relies upon a robust FWG circuit where a TE10 mode propagates through a serpentine, rectangular waveguide as the electron beam travels through a beam hole along the axis of the circuit. The FWG slows the RF phase velocity relative to the electron beam, enabling synchronous interaction and net gain.

A 0.85 THz vacuum-based power amplifier

A 0.850 THz vacuum electronic power amplifier capable of >;100mW output power is being developed at Northrop Grumman Electronic Systems. The compact power amplifier is based on a DRIE-fabricated folded waveguide slow-wave circuit, together with a high current density thermionic cathode, a high field permanent magnet solenoid, and a single-stage depressed collector for overall device efficiency. The new 0.85 THz power amplifier design is based on a 0.67 THz amplifier that achieved over 100mW of output power with 21.5 dB of gain, 15 GHz of operational bandwidth, a collector efficiency of 93% and an overall device efficiency of 0.44%.

233 GHz high Power amplifier development at Northrop Grumman

Northrop Grumman has developed a folded-waveguide vacuum electronic high power amplifier at 233 GHz. The amplifier demonstrates output power over 79 W (49 dBm) from 232.6-234.6 GHz, and greater than 50 W (47 dBm) over a 2.4 GHz instantaneous bandwidth. Saturated gain is approximately 23-24 dBm over this bandwidth, with an input drive of 26-27 dBm required for saturated output power. The device operating point is 20.95kV, 114mA for a frequency range centered at 233.6 GHz, but is capable of producing 50W at frequencies up to 237.8 GHz by varying the operating voltage. Typical instantaneous (3 dB) operating bandwidth ranges from 2.4-3.0 GHz for a beam voltage range of 20.5-21 kV. The amplifier uses a compact permanent magnet solenoid for beam focusing and confinement, and typically achieves 95-98% beam transmission through the folded-waveguide circuit and into the single-section depressed collector. This device has demonstrated operational duty cycles up to 50% with liquid cooling and using Northrop Grummans Microwave Power Module compact integrated power conditioner technology. A more compact version of this power amplifier is being developed with emphasis on reducing the size of the permanent magnet solenoid.

A multiple electron beam array for a 220 GHz amplifier

An electron beamlet array is being developed for use with power-combined, micro-machined folded waveguide circuits for a 50W, 220 GHz submillimeter RF device.