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Simons, Rainee N.

Publications and source records attributed to Simons, Rainee N..

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2019

Multi-Band and Multi-Function Reconfigurable Gallium Nitride Based Fully Solid-State Microwave Power Module for Cognitive Radio/Radar Platforms

This paper presents as a proof-of-concept (POC) the design, integration, and performance of a novel reconfigurable S-/X-band Gallium Nitride (GaN) based fully solid-state microwave power module (SSMPM) for the role as the transmit module in a cognitive radio (CR). The SSMPM synergistically integrates multiple amplifiers through diplexing and high power switches to enable a single SSMPM capable of functioning as both S-/X-band amplifiers for telemetry, tracking, and command (TT&C), telecommunications, and science data downlink or as X-band radar for proximity sensing onboard a planetary exploration spacecraft. Integration of an electric field shaping field plate (FP) onto the GaN high electron mobility transistors (HEMTs) in this SSMPM provides increased performance and reliability for operation in the harsh conditions of space. This SSMPM is capable of delivering saturated power (Psat) of 39 dBm (8 W continuous wave (CW)) at S-band, P(sub sat) of 43 dBm (20 W CW) at X-band, and P(sub sat) of >50 dBm (>100 W Pulsed) at X-band.

Simons, Rainee N.↗
NASA NTRS2019

A Novel Reconfigurable GaN Based Fully Solid-State Microwave Power Module for Communications/Radar Applications

The paper presents as a proof-of-concept (POC) the design, integration, and performance of a novel reconfigurableS-/X-band, GaN based, fully solid-state microwave power module (SSMPM) to enable miniaturization of the overall RFsystem. The SSMPM includes diplexers, pre-amplifiers, a multistage medium power amplifier, SPDT switches, andCW/Pulsed high-power amplifiers. These components are synergistically integrated such that a single SSMPM is capable of being dynamically reconfigured to function as a CW S-/X-band amplifier for TT&C/science data downlink and as a pulsed X-band amplifier for remote sensing radar onboard a planetary exploration spacecraft. The POC SSMPM is capable of delivering Psat of 39 dBm (8 W CW) at S-band, P(sub sat) of 46 dBm (40 W CW) at X-band, and P(sub sat) of >50 dBm (>100 W Pulsed) at X-band.

Simons, Rainee N.↗
NASA NTRS2019

A Novel Reconfigurable GaN Based Fully Solid-State Microwave Power Module for Communications/Radar Applications

In this paper, we present as a proof-of-concept (POC) the design, integration, and performance of a novel reconfigurable GaN based fully solid-state MPM. The module synergistically integrates diplexers, pre-amplifiers, multistage medium power amplifiers (MPAs), SPDT switches, and CW/Pulsed high power amplifiers (HPAs) with a voltage sequencer, a DC blanking controller, and a low voltage electronic power conditioner. The POC SSMPM operates at both S-band and X-band to serve multiple roles. The SSMPM can be reconfigured to deliver Psat of 39 dBm (8 W CW) at S-band, Psat of 46 dBm (40 W CW) at X-band, and Psat of >50 dBm (>100 W Pulsed) at X-band. Lastly, our link budget calculations indicate that the SSMPM with Psat = 40 W when coupled to a 10 cm X-band transmit antenna on a low Earth orbiting (900 km) satellite can close a 1 Gbps (QPSK) data downlink to a 1 m receive antenna on ground with 3 dB margin.

Simons, Rainee N.↗
NASA NTRS2018

High/Low Temperature Contactless Radio Frequency Probes

A contactless radio frequency (RF) probe with inverted microstrip lines. The RF probe includes a microstrip associated with a device under test, and a broadside coupled inverted microstrip line configured to exchange RF signals to a network analyzer.

Jordan, Jennifer L.↗
NASA NTRS2018

A Novel Reconfigurable GaN Based Fully Solid-State Microwave Power Module for Communications/Radar Applications

The paper presents the design, integration, and performance of a novel S-/X-band, GaN based, fully solid-state microwave power module (SSMPM). The SSMPM includes diplexers, pre-amplifiers, a multi-stage medium power amplifier, SPDT switches, and CW/Pulsed high-power amplifiers. These components are synergistically integrated such that a single SSMPM is capable of being dynamically reconfigured to function as a S-/X-band amplifier for TT&C/telecommunications for command/science date downlink and radar for remote sensing onboard a planetary exploration spacecraft. The SSMPM is capable of delivering Psat of 39.5 dBm (~10 W CW) at S-band, Psat of 46.7 dBm (~45 W CW) at X-band, and Psat of 51.2 dBm (~122 W Pulsed) at X-band.

Microwave Amplifier↗
NASA NTRS2018

Ka-Band Waveguide Hybrid Divider with Unequal and Arbitrary Power Output Ratio

One or more embodiments of the present invention describe an apparatus and method to combine unequal powers. The apparatus includes a first input port, a second input port, and a combiner. The first input port is operably connected to a first power amplifier and is configured to receive a first power from the first power amplifier. The second input port is operably connected to a second power amplifier and is configured to receive a second power from the second power amplifier. The combiner is configured to simultaneously receive the first power from the first input port and the second power from the second input port. The combiner is also configured to combine the first power and second power to produce a maximized power. The first power and second power are unequal.

Simons, Rainee N.↗
NASA NTRS2017

Reconfigurable Wideband Circularly Polarized Stacked Square Patch Antenna for Cognitive Radios

An almost square patch, a square patch and a stacked square patch with corner truncation for circular polarization (CP) are researched and developed at X-band for cognitive radios. Experimental results indicate, first, that the impedance bandwidth of a CP almost square patch fed from the edge by a 50 ohm line is 1.70 percent and second, that of a CP square patch fed from the ground plane side by a surface launch connector is 1.87 percent. Third, the impedance bandwidth of a CP stacked square patch fed by a surface launch connector is 2.22 percent. The measured center frequency for the CP square patch fed by a surface launch connector without and with an identical stacked patch is 8.45 and 8.1017 GHz, respectively. By stacking a patch, separated by a fixed air gap of 0.254 mm, the center frequency is observed to shift by as much as 348.3 MHz. The shift in the center frequency can be exploited to reconfigure the operating frequency by mechanically increasing the air gap. The results indicate that a tuning bandwidth of about 100 MHz can be achieved when the distance of separation between the driven patch and the stacked patch is increased from its initial setting of 0.254 to 1.016 mm.

Cognitive↗
NASA NTRS2017

Multiband Reconfigurable Harmonically Tuned Gallium Nitride (GaN) Solid-State Power Amplifier (SSPA) for Cognitive Radios

The paper presents the architecture of a wideband reconfigurable harmonically-tuned Gallium Nitride (GaN) Solid State Power Amplifier (SSPA) for cognitive radios. When interfaced with the physical layer of a cognitive communication system, this amplifier topology offers broadband high efficiency through the use of multiple tuned input/output matching networks. This feature enables the cognitive radio to reconfigure the operating frequency without sacrificing efficiency. This paper additionally presents as a proof-of-concept the design, fabrication, and test results for a GaN inverse Class-F type amplifier operating at X-band (8.4 GHz) that achieves a maximum output power of 5.14-W, Power Added Efficiency (PAE) of 38.6 percent, and Drain Efficiency (DE) of 48.9 percent under continuous wave (CW) operation.

Cognitive↗
NASA NTRS2017

A Ka-Band (26 GHz) Circularly Polarized 2x2 Microstrip Patch Sub-Array with Compact Feed

A Ka-Band (26 gigahertz) 2 by 2 sub-array with square-shaped microstrip patch antenna elements having two truncated corners for circular polarization (CP) is presented. In addition, the layout for a new compact microstrip feed network for the sub-array is also presented. The compact feed network offers a footprint size reduction of near 60 percent over traditional sub-array at 26 gigahertz. Experimental data indicates that a truncation amount a equals 0.741 millimeters for an isolated patch element results in a return loss (S (sub II)) of minus 35 decibels at 26.3 gigahertz. Furthermore, the measured S (sub II) for the proof-of-concept sub-array with the above elements is better than minus 10.0 decibels at 27.7 gigahertz. However, the impedance match and the operating frequency can be fine-tuned to 26 gigahertz by adjusting the feed network dimensions. Lastly, good agreement is observed between the measured and simulated S (sub II) for the subarray for both right hand and left hand CP. The goal of this effort is utilize the above sub-array as a building block for a larger N by N element array, which would serve as a feed for a reflector antenna for satellite communications.

Microstrip↗
NASA NTRS2017

Wideband Reconfigurable Harmonically Tuned GaN SSPA for Cognitive Radios

The paper presents the architecture of a wideband reconfigurable harmonically-tuned Gallium Nitrate (GaN) Solid State Power Amplifier (SSPA) for cognitive radios. When interfaced with the physical layer of a cognitive communication system, this amplifier topology offers broadband high efficiency through the use of multiple tuned input/output matching networks. This feature enables the cognitive radio to reconfigure the operating frequency without sacrificing efficiency. This paper additionally presents as a proof-of-concept the design, fabrication, and test results for a GaN inverse class-F type amplifier operating at X-band (8.4 GHz) that achieves a maximum output power of 5.14-W, Power Added Efficiency (PAE) of 38.6, and Drain Efficiency (DE) of 48.9 under continuous wave (CW) operation.

Cognitive↗
NASA NTRS2017

Reconfigurable Wideband Circularly Polarized Stacked Square Patch Antenna for Cognitive Radios

An almost square patch, a square patch and a stacked square patch with corner truncation for circular polarization (CP) are researched and developed at X-band for cognitive radios. Experimental results indicate, first, that the impedance bandwidth of a CP almost square patch fed from the edge by a 50 ohm line is 1.70% and second, that of a CP square patch fed from the ground plane side by a surface launch connector is 1.87%. Third, the impedance bandwidth of a CP stacked square patch fed by a surface launch connector is 2.22%. The measured center frequency for the CP square patch fed by a surface launch connector without and with an identical stacked patch is 8.45 and 8.1017 GHz, respectively. By stacking a patch, separated by a fixed air gap of 0.254 mm, the center frequency is observed to shift by as much as 348.3 MHz. The shift in center frequency, brought about by the reconfiguring of the physical layer antenna, can be exploited in a cognitive system since it expands the usable frequency spectrum for software reconfiguration in the presence of interference. In addition, varying the fixed air gap in the stacked antenna geometry by increments of 0.254 mm further expands the usable frequency spectrum.

Cognitive↗
NASA NTRS2017

Waveguide Multimode Directional Coupler for Harvesting Harmonic Power from the Output of Traveling-Wave Tube Amplifiers

The paper presents the design, fabrication, and test results for a novel waveguide multimode directional coupler (MDC). The coupler fabricated from dissimilar frequency band waveguides, is capable of isolating power at the 2nd harmonic frequency from the fundamental power at the output port of a high power traveling-wave tube amplifier. The major advantage of the MDC is significantly lower insertion loss compared to a diplexer. The presentation slides for the paper that was approved is attached. The tracking number for the paper that was approved is TN 37015.

Directional Coupler↗
NASA NTRS2017

Waveguide Multimode Directional Coupler for Harvesting Harmonic Power from the Output of Traveling-Wave Tube Amplifiers

This paper presents the design, fabrication, and test results for a novel waveguide multimode directional coupler (MDC). The coupler fabricated from dissimilar frequency band waveguides, is capable of isolating power at the 2nd harmonic frequency from the fundamental power at the output port of traveling-wave tube amplifiers. Test results from proof-of-concept demonstrations are presented for Ku/Ka-band and Ka/E-band MDCs, which demonstrate sufficient power in the 2nd harmonic for a space borne beacon source for mm-wave atmospheric propagation studies.

Directional Coupler↗
NASA NTRS2016

Optical Tunable-Based Transmitter for Multiple Radio Frequency Bands

An optical tunable transmitter is used to transmit multiple radio frequency bands on a single beam. More specifically, a tunable laser is configured to generate a plurality of optical wavelengths, and an optical tunable transmitter is configured to modulate each of the plurality of optical wavelengths with a corresponding radio frequency band. The optical tunable transmitter is also configured to encode each of the plurality of modulated optical wavelengths onto a single laser beam for transmission of a plurality of radio frequency bands using the single laser beam.

Nguyen, Hung↗