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A fully integrated broadband sub-mmWave chip-to-chip interconnect

Published in:
IEEE Trans. Microw. Theory Tech., Vol. 65, No. 7, July 2017, pp. 2373-86.

Summary

A new type of broadband link enabling extremely high-speed chip-to-chip communication is presented. The link is composed of fully integrated sub-mmWave on-chip traveling wave power couplers and a low-cost planar dielectric waveguide. This structure is based on a differentially driven half-mode substrate integrated waveguide supporting the first higher order hybrid microstrip mode. The cross-sectional width of the coupler structure is tapered in the direction of wave propagation to increase the coupling efficiency and maintain a large coupling bandwidth while minimizing its on-die size. A rectangular dielectric waveguide, constructed from Rogers Corporation R3006 material, is codesigned with the on-chip coupler structure to minimize coupling loss. The coupling structure achieves an average insertion loss of 4.8 dB from 220 to 270 GHz, with end-to-end link measurements presented. This system provides a packaging-friendly, cost effective, and high performance planar integration solution for ultrabroadband chip-to-chip communication utilizing millimeter waves.
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Summary

A new type of broadband link enabling extremely high-speed chip-to-chip communication is presented. The link is composed of fully integrated sub-mmWave on-chip traveling wave power couplers and a low-cost planar dielectric waveguide. This structure is based on a differentially driven half-mode substrate integrated waveguide supporting the first higher order hybrid...

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Nonlinear equalization of microwave photonic links

Published in:
IEEE Int. Topical Meeting on Microwave Photonics, MWP 2016, 31 October - 3 November 2016.

Summary

High dynamic range is a key requirement in advanced microwave photonic systems. We demonstrate compensation of nonlinearities occurring in microwave photonic links using a novel digital nonlinear equalization technique and demonstrate suppression of distortion products by 33 dB with a small number of equalizer coefficients.
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Summary

High dynamic range is a key requirement in advanced microwave photonic systems. We demonstrate compensation of nonlinearities occurring in microwave photonic links using a novel digital nonlinear equalization technique and demonstrate suppression of distortion products by 33 dB with a small number of equalizer coefficients.

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Reconfigurable RF systems using commercially available digital capacitor arrays

Published in:
38th Annual GOMACTech Conf., 11-14 March 2013.
R&D group:

Summary

Various RF circuit blocks implemented by using commercially available MEMS digital capacitor arrays are presented for reconfigurable RF systems. The designed circuit blocks are impedance-matching network, tunable bandpass filter, and VSWR sensor. The frequency range of the designed circuits is 0.4-4GHz. The MEMS digital capacitor arrays that are employed in the designs have built-in dc-to-dc voltage converter and serial interface significantly simplifying the control circuitry. The RF circuit blocks are suitable to low-cost, high-level of integration, thanks to the commercially available parts and standard RF packaging technologies.
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Summary

Various RF circuit blocks implemented by using commercially available MEMS digital capacitor arrays are presented for reconfigurable RF systems. The designed circuit blocks are impedance-matching network, tunable bandpass filter, and VSWR sensor. The frequency range of the designed circuits is 0.4-4GHz. The MEMS digital capacitor arrays that are employed in...

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Nanosatellites for Earth environmental monitoring: the MicroMAS project

Summary

The Micro-sized Microwave Atmospheric Satellite (MicroMAS) is a 3U cubesat (34x10x10 cm, 4.5 kg) hosting a passive microwave spectrometer operating near the 118.75-GHz oxygen absorption line. The focus of the first MicroMAS mission (hereafter, MicroMAS-1) is to observe convective thunderstorms, tropical cyclones, and hurricanes from a near-equatorial orbit at approximately 500-km altitude. A MicroMAS flight unit is currently being developed in anticipation of a 2014 launch. A parabolic reflector is mechanically rotated as the spacecraft orbits the earth, thus directing a cross-track scanned beam with FWHM beamwidth of 2.4-degrees, yielding an approximately 20-km diameter footprint at nadir incidence from a nominal altitude of 500 km. Radiometric calibration is carried out using observations of cold space, the earth?s limb, and an internal noise diode that is weakly coupled through the RF front-end electronics. A key technology feature is the development of an ultra-compact intermediate frequency processor module for channelization, detection, and A-to-D conversion. The antenna system and RF front-end electronics are highly integrated and miniaturized. A MicroMAS-2 mission is currently being planned using a multiband spectrometer operating near 118 and 183 GHz in a sunsynchronous orbit of approximately 800-km altitude. A HyMAS- 1 (Hyperspectral Microwave Atmospheric Satellite) mission with approximately 50 channels near 118 and 183 GHz is also being planned. In this paper, the mission concept of operations will be discussed, the radiometer payload will be described, and the spacecraft subsystems (avionics, power, communications, attitude determination and control, and mechanical structures) will be summarized.
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Summary

The Micro-sized Microwave Atmospheric Satellite (MicroMAS) is a 3U cubesat (34x10x10 cm, 4.5 kg) hosting a passive microwave spectrometer operating near the 118.75-GHz oxygen absorption line. The focus of the first MicroMAS mission (hereafter, MicroMAS-1) is to observe convective thunderstorms, tropical cyclones, and hurricanes from a near-equatorial orbit at approximately...

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A compressed sensing analog-to-information converter with edge-triggered SAR ADC core

Published in:
ISCAS 2012: IEEE Int. Symp. on Circuits and Systems, 20-23 May 2012, pp. 3162-3165.

Summary

This paper presents the design and implementation of an analog-to-information converter (AIC) based on compressed sensing. The core of the AIC is an edge-triggered charge-sharing SAR ADC. Compressed sensing is achieved through random sampling and asynchronous successive approximation conversion using the ADC core. Implemented in 90nm CMOS, the prototype SAR ADC core achieves a maximum sample rate of 9.5MS/s, an ENOB of 9.3 bits, and consumes 550 mu W from a 1.2V supply. Measurement results of the compressed sensing AIC demonstrate effective sub-Nyquist random sampling and reconstruction of signals with sparse frequency support suitable for wideband spectrum sensing applications. When accounting for the increased input bandwidth compared to Nyquist, the AIC achieves an effective FOM of 10.2fJ/conversion-step.
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Summary

This paper presents the design and implementation of an analog-to-information converter (AIC) based on compressed sensing. The core of the AIC is an edge-triggered charge-sharing SAR ADC. Compressed sensing is achieved through random sampling and asynchronous successive approximation conversion using the ADC core. Implemented in 90nm CMOS, the prototype SAR...

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Design and analysis of a hyperspectral microwave receiver subsystem

Published in:
MICRORAD 2012, 12th Specialist Meeting on Microwave Radiometry and Remote Sensing of the Environment, 5-9 March 2012.

Summary

Recent technology advances have profoundly changed the landscape of modern radiometry by enabling miniaturized, low-power, and low-noise radio-frequency receivers operating at frequencies near 200 GHz and beyond. These advances enable the practical use of receiver arrays to multiplex multiple broad frequency bands into many spectral channels. We use the term "hyperspectral microwave" to refer generically to microwave sounding systems with approximately 50 spectral channels or more. In this paper, we report on the design and analysis of the receiver subsystem (lensed antenna, RF frontend electronics, and IF processor module) for the Hyperspectral Microwave Atmospheric Sounder (HyMAS) comprising multiple receivers near the oxygen absorption line at 118.75 GHz and the water vapor absorption line at 183.31 GHz. The hyperspectral microwave receiver system will be integrated into a new scanhead compatible with the NASA GSFC Conical Scanning Microwave Imaging Radiometer/Compact Submillimeter-wave Imaging Radiometer (CoSMIR/CoSSIR) airborne instrument system to facilitate demonstration and performance characterization under funding from the NASA ESTO Advanced Component Technology program. Four identical radiometers will be used to cover 108-119 GHz, and two identical receivers will be used to cover 173-183 GHz. Subharmonic mixers will be driven by frequency-multiplied dielectric resonant oscillators, and single-sideband operation will be achieved by waveguide filtering of the lower sideband. A relatively high IF frequency is chosen to facilitate miniaturization of the IF processor module, which will be fabricated using Low Temperature Co-fired Ceramic (LTCC) technology. Corrugated feed antennas with lenses are used to achieve a FWHM beamwidth of approximately 3.5 degrees. Two polarizations are measured by each feed to increase overall channel count, and multiple options will be considered during the design phase for the polarization diplexing approach. Broadband operation over a relatively high intermediate frequency range (18-29 GHz) is a technical challenge of the front-end receiver systems, and a receiver temperature of approximately 2000-3000K is expected over the receiver bandwidth. This performance, together with approximately l00-msec integration times typical of airborne operation, yields channel NEDTs of approximately 0.35K, which is adequate to demonstrate the hyperspectral microwave concept by comparing profile retrievals with high-fidelity ground truth available either by coincident overpasses of hyperspectral infrared sounders and/or in situ radiosonde/dropsonde measurements.
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Summary

Recent technology advances have profoundly changed the landscape of modern radiometry by enabling miniaturized, low-power, and low-noise radio-frequency receivers operating at frequencies near 200 GHz and beyond. These advances enable the practical use of receiver arrays to multiplex multiple broad frequency bands into many spectral channels. We use the term...

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A low-loss double-tuned transformer

Published in:
IEEE Microw. Wirel. Compon. Lett., Vol. 17, No. 11, November 2007, pp. 772-774.
Topic:
R&D group:

Summary

In this letter, we present a state-of-the-art, planar double-tuned transformer using high- , micromachined spiral inductors and integrated capacitors. This circuit provides a 4:1 impedance transformation over a 30% bandwidth centered at 4.06 GHz, with a minimum insertion loss of 1.50 dB. The fabricated circuit occupies a total area of 440 500 m2 and finds application in power amplifier and other matching applications. An accurate lumped-element circuit model and design tradeoffs are presented. We believe this is the first implementation of a planar microwave double-tuned transformer.
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Summary

In this letter, we present a state-of-the-art, planar double-tuned transformer using high- , micromachined spiral inductors and integrated capacitors. This circuit provides a 4:1 impedance transformation over a 30% bandwidth centered at 4.06 GHz, with a minimum insertion loss of 1.50 dB. The fabricated circuit occupies a total area of...

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A 16mW 8Mbps fractional-n FSK modulator at 15.8-18.9GHz

Published in:
2007 IEEE Radio Frequency Integrated Circuits Symp., 3-5 June 2007, pp. 533-536.

Summary

Indirect modulation of fractional-N synthesizers is an energy-efficient architecture capable of moderate data rates, and is well-suited for use in sensor networks or WLAN. Although the architecture is used primarily at low RF frequencies, the capability for fractional- N synthesizers at Ku-band and above currently exist in available silicon technology. Recent demonstrations at 10- 25GHz show promising results, although power consumption at this higher frequency remains high for small batterypowered devices. This work implements a fully-integrated fractional-N synthesizer optimized for power efficient modulation at 15.8 to 18.9GHz with an 80MHz reference. Binary and 4-ary FSK modulation of up to 8Mbps is achieved while consuming 16mW in IBM 0.18um SiGe BiCMOS.
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Summary

Indirect modulation of fractional-N synthesizers is an energy-efficient architecture capable of moderate data rates, and is well-suited for use in sensor networks or WLAN. Although the architecture is used primarily at low RF frequencies, the capability for fractional- N synthesizers at Ku-band and above currently exist in available silicon technology...

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A sub-10mW 2Mbps BFSK transceiver at 1.35 to 1.75GHz.

Published in:
2007 IEEE Radio Frequency Integrated Circuits Symp., 3-5 June 2007, pp. 97-100.
Topic:
R&D group:

Summary

This work presents the design and measurement of a 2Mbps BFSK transceiver at 1.35 to 1.75GHz for use in wireless sensor node applications. The receiver is a direct conversion architecture and has a sensitivity of -74dBm at 2Mbps and consumes 8.0mW. The transmitter generates orthogonal BFSK modulation through the use of digital pre-emphasis of the synthesizer frequency control word and consumes 9.7mW including the power amplifier. The transmitter delivers >3dBm of output power for a total transmitter power efficiency of 23% and a transmitter FOM of 4.85nJ/bit at 2Mbps.
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Summary

This work presents the design and measurement of a 2Mbps BFSK transceiver at 1.35 to 1.75GHz for use in wireless sensor node applications. The receiver is a direct conversion architecture and has a sensitivity of -74dBm at 2Mbps and consumes 8.0mW. The transmitter generates orthogonal BFSK modulation through the use...

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