Benjamin Schoch

Zusammenfassung

Intermodulation effects play a decisive role in any system relying on the linear transmission of signals, such as highspeed wireless communication. For the first time, this paper presents measured third-order and fifth-order intermodulation performance of a 300GHz monolithic integrated circuit with a new photonic approach. Conventional amplifier characterization in this frequency range showed a small-signal gain of more than 15dB, operating frequency range from 279 to 313GHz, and a 1dB compression point and saturated output power of 1.6dBm and 6dBm, respectively, from a one-tone power sweep. Using a novel photonic-based measurement setup, the amplifiers' output-related IP3 and IP5 are measured to 13dBm and 11dBm, respectively. The two-tone measurement uses the photonic mixing of three laser lines to generate the two-beat frequencies at 299 and 301GHz.

Zusammenfassung

This paper introduces the system architecture, implementation and measured characterization of the FPGA-based adaptive onboard payload computer used for an in-orbit verification of an E-band high bandwidth communication system. The mission goal is to evaluate the atmospheric effects on a multiGigabit data-downlink, in the frequency range of 71-76 GHz with a data rate of minimum 10 Gbit/s, from a 6U CubeSat in low earth orbit to a ground station. The miniaturized onboard payload computer in conjunction with a fast digital-to-analog converter shall serve as an arbitrary waveform generator and as image processing unit.

Zusammenfassung

This contribution details the motivation and the status of a new satellite mission, which targets the in-orbit verification of a wideband satellite communication link operating in the high millimeter-wave regime at 71-76 GHz. The paper reviews the dynamic link budgets for data links between satellites in low-earth orbits and ground stations on close to sea level, taking into account the expected atmospheric attenuation according to lTU models and supported by successful terrestrial transmission experiments, which confirm the feasibility and attractiveness of exploiting allocated spectrum in E-band for Gigabit satellite feeder links of globe-spanning satellite constellations and high capacity data downlinks in earth observation, even under adverse weather conditions. The scientific payload, hosted by a 6V-Cubsat platform, comprises a high-performance E-band transmitter with GaN-based solid state power amplifiers, an InGaAs-based low-noise receiver and a modern FPGA-based digital processing unit realizing AWG functionality and 4k image/video storage. The ground terminal employs a highly directive Cassegrain antenna with coarse GPS and fine RF tracking and a low-noise receiver.

Zusammenfassung

This paper presents an E-band (60 - 90GHz) balanced driver amplifier in a 50nm InGaAs-based metamorphic high electron mobility transistor technology. The amplifier is realized as a millimeter-wave monolithic integrated circuit and is designed to drive a high power output stage in a multi-gigabit communication system. The three stage driver amplifier is balanced via 90° hybrid Lange couplers. To track the power levels, especially to fulfill regulated power density requirements, a detector was placed at the output of the amplifier. On-wafer measurements were performed and a maximum gain of 35dB at 66GHz could be achieved. Between 60 to 90GHz a gain greater than 30dB could be measured which results in a gain-bandwidth product of 1.8THz. With four parallel common source transistors in the output stage a maximum output power of 14.5dBm at 73.5GHz could be reached.

Zusammenfassung

This paper presents ongoing activities towards an in-orbit verification of an E-band high bandwidth communication system to exploit a new spectrum for broadband satellite communication by demonstrating a data-downlink, using solid state technologies for the RF analog transmit front end, in the frequency range of 71-76 GHz with a data rate of 5 Gbit/s from a three-axis stabilized 6U nano-satellite in low earth orbit to a ground station. A recent plane-to-ground data transmission has successfully validated the technology platform, and dynamic link budgets suggest the feasibility of LEO to ground links exploiting E-band frequencies.

Zusammenfassung

A wireless communication link operating in E-band at 71-76 GHz with 30 dBm of transmit power from a GaN-based solid-state power amplifier and a 3-dB noise Figure of its GaAs-based receiver is employed in a data transmission with up to 9.8 Gbit/s data rate between a plane and a ground station. Flying at a height of 1000 m above ground and at distances between 5 and 12 km from the receiver, a microlight aircraft hosts the payload mounted to its wing. The highly directional link is formed by a 39.7 dBi gain Cassegrain parabolic antenna in the plane-mounted transmitter, and a 48.7 dBi Cassegrain antenna with GPS-based antenna tracking in the ground terminal. Stable data links were established with up to 9.8 Gbit/s data rate employing QPSK, 8-PSK and 16-QAM modulation.

Zusammenfassung

In this paper, a performance analysis of a full-duplex E-band link is reported. The transmission system is operated with a real-time capable modem as a digital signal processing unit with broadband mixed-signal blocks. The measurement has been done with a 1.425 gigabaud-per-second data rate transmission for higher order modulations. A raised-cosine pulse-shaping filter is used with a 0.5 roll-off factor. A residual bit-error-rate which is below the forward-error correction limit is measured. The uplink (81–86 GHz band) transceiver and the downlink (71–76 GHz band) transceiver of the E-band duplex-link provide a 64-QAM transmission which has a 7.5 gigabit-per-second data-rate with a back-to-back configured setup. The 32-QAM and the 16-QAM which provide 6.2 and 5 gigabit-per-second data transmission, respectively are analyzed as well. The paper analyzes the influence of the main analog front-end impairments, noise and amplifier compression, including a real-time capable modem sensitivity over the entire full-duplex E-band communication system performance, i.e. their upper and lower threshold limit for the received power, for different modulation formats and relates these limits to the power compression of the analog frontend's transfer characteristics.

Zusammenfassung

This work describes the dynamic link budgets arising in ultra-high data rate satellite communication links in the E- and W-band operating in low earth orbits (LEO). The calculations take into account all available ITU models for atmospheric effects, the current state of the art in achievable system gain, i.e. transmit power and receiver sensitivity, prospective antenna realisations, and arbitrary low-earth orbits and locations of ground terminals. In this work, we calculate link-budgets for different LEO scenarios for defined ground stations. The communication systems are described on a high-level basis, where it is possible to estimate the link quality and capacity. The communication system is derived from state-of-art performance of E/W-band components. Antenna sizes, pointing accuracy and probability densities are taken into account to describe a full satellite mission with focus on the communication channel. A time dependent SNR can be estimated to calculate thresholds for modulation formats and link reliability. Calculation are made to predict the energy per useful bit to noise density ratio (E b /N 0 ) for a LEO- satellite pass through the zenith at an orbit altitude of 400 km. Finally, the achievable data volume can be estimated for each atmospheric situation, e.g. weather condition, which can be offloaded from the satellite.

Zusammenfassung

This paper presents a highly broadband quadrature down-converter with a center frequency of 300GHz and a low-noise amplifier (LNA) with a bandwidth of 80GHz. The operation frequency between 235GHz and 315GHz enables the usage in future wireless high data rate applications. The submillimeter-wave monolithic integrated circuits (S-MMICs) are realized using a 35nm metamorphic high electron mobility transistor (mHEMT) technology based on InAlAs/InGaAs. The down-converter integrates a frequency multiplier by four, a buffer amplifier and a passive fundamental I/Q mixer and reaches a conversion gain of -15dB and an RF bandwidth of 60GHz. The low-noise amplifier has an average gain of 26dB over the 3dB bandwidth. A total conversion gain of the receiver of 11dB is therefore reached by combining the down-converter and the LNA.

Zusammenfassung

In this paper we present a transmit and receive MMIC for FMCW radar. The transmitter consisting of a frequency multiplier-by-three and a power amplifier featuring a high output power of 7 dBm with a 60 GHz 3-dB RF-bandwidth. The receiver is designed to be highly linear over a LO and RF bandwidth from 235 to 285 GHz. It employs a frequency tripler and a power amplifier as driver stage for a passive I/Q downconverter which enables an image reject architecture. To ensure linear operation and improve the overall receiver noise an input amplifier stage with an input referred 1-dB compression point exceeding -3 dBm is also integrated. The chipset is realized in a 35 nm metamorphic high electron mobility transistor technology.

Zusammenfassung

In this paper, a performance analysis of a full-duplex E-band link is reported. The transmission system is operated with a real-time capable modem as a digital signal processing unit with broadband mixed-signal blocks. The measurement has been done with a 1.425 gigabaud-per-second data rate transmission for higher order modulations. A raised-cosine pulse-shaping filter is used with a 0.5 roll-off factor. A residual bit-error-rate which is below the forward-error correction limit is measured. The uplink (81–86 GHz band) transceiver and the downlink (71–76 GHz band) transceiver of the E-band duplex-link provide a 64-QAM transmission which has a 7.5 gigabit-per-second data-rate with a back-to-back configured setup. The 32-QAM and the 16-QAM which provide 6.2 and 5 gigabit-per-second data transmission, respectively are analyzed as well. The paper analyzes the influence of the main analog front-end impairments, noise and amplifier compression, including a real-time capable modem sensitivity over the entire full-duplex E-band communication system performance, i.e. their upper and lower threshold limit for the received power, for different modulation formats and relates these limits to the power compression of the analog frontend's transfer characteristics.

Zusammenfassung

This paper presents a broadband H-Band (220-325 GHz) power amplifier in a 35nm InGaAs-based metamorphic high electron mobility transistor technology. The amplifier is realized as a submillimeter-wave monolithic integrated circuit and is designed to drive a high power amplifier in a multi-gigabit communication system or to be implemented in a wideband millimeter-wave radar to detect imperfections in materials. A five-stage amplifier S-MMIC based on common-source gain cells was realized and measured on-wafer with a maximum gain of 14.7dB at 245 GHz. The 3-dB-bandwidth is from 238 to 292 GHz with a gain variation of around 2dB. The amplifier has four parallel transistors in the last two stages and provides up to 4 dBm of output power, under 1dB gain compression. A saturated output power of 6.7 dBm at 280GHz could be measured.

Zusammenfassung

This paper presents a broadband H-band (220 -325 GHz) power amplifier in a 35 nm InGaAs-based metamorphic high electron mobility transistor technology. The amplifier is realized as a submillimeter-wave monolithic integrated circuit (S-MMIC) and is designed to drive a high power amplifier in a multi-gigabit communication system. The five-stage amplifier S-MMIC based on common-source gain cells was realized and measured on-wafer with a maximum gain of 23 dB at 285 GHz. The lower and higher cutoff frequency is 278 and 335 GHz, respectively, with a gain variation of around 4 dB. The amplifier has four parallel transistors in the last two stages and provides a saturated output power of 8 dBm at 300 GHz. A gain-bandwidth product (GBW) of 508 GHz could be achieved.

Zusammenfassung

The Russians launched the first artificial Earth satellite, Sputnik 1, into an elliptical low-Earth orbit (LEO) in October 1957. Through its four external antennas, Sputnik 1 broadcast radio beacons at 20.005 and 40.01 MHz to study the density of the atmosphere and the radio-wave propagation through the ionosphere. This historic event represents the advent of the satellite age. Since then, satellites have become an integral part of global navigation, Earth observation, broadcasting, and communication systems. The latter complements conventional wired and wireless terrestrial communication and provides an effective platform to relay radio signals between two arbitrary points on or near the Earth. Satellite communication offers end users a high level of flexibility. Irrespective of the geological coordinate, the user can benefit from a broad spectrum for various applications, from two-way voice and data communication to video conferencing.

Zusammenfassung

A compact receiver MMIC for a 300 GHz wireless communication system has been developed in a 35 nm mHEMT technology. The circuit integrates an active frequency multiplier by three and a buffer amplifier for the LO signal, a single balanced, quadrature, fundamental resistive down-converter and an RF pre-amplifier. The chip measurements have shown that the receiver exhibits a conversion gain of -1 dB and a 3-dB bandwidth of 30 GHz. The DC power consumption of the receiver is 110 mW.