Publications Search Results
1 - 10 of 49
-
PublicationWideband Cross-Domain Characterization of a W-band Amplifier MMIC( 2023)In this paper, we present a novel on-chip multi-tone characterization of a millimeter-wave amplifier MMIC in a waveguide environment covering W-band frequencies. The measurement setup comprises extension modules in WR-10, where a new architecture with a wideband RF input enables source calibration. The setup is capable of measuring small-signal parameters while the same configuration is able to excite wideband multi-tone or complex modulated signals and measure the signal response for a time-domain analysis. The in-situ combination of an analog millimeter-wave frequency domain setup with digitally modulated wideband time domain entities is described as a cross-domain measurement setup. A W-band power amplifier chip is used as a device-under-test, where a multi-tone test is conducted and the response of complex modulated signals is analyzed.
-
PublicationSingle-Ended Resistive Down-Converter MMICs in InGaAs mHEMT and GaN-HEMT Technologies for D-Band (110-170 GHz) Applications( 2023)
-
PublicationThe technology platform of the EIVE CubeSat mission for high throughput downlinks at W-band( 2023)This paper details the motivation and the status of a new satellite mission, which targets the in-orbit verification of a wide band satellite communication link, operating in the high millimeter-wave regime at 71–76 GHz. Under ideal weather conditions, data rates over 15 Gb/s in complex modulation formats are expected to be demonstrated in-orbit, while data rates over 6 Gb/s are still expected under adverse atmospheric and weather conditions. The scientific payload, hosted by a 6U-CubeSat platform, comprises a high-performance W-band transmitter with GaN-based solid state power amplifiers, an InGaAs-based low-noise receiver and a modern FPGA-based digital processing unit, realizing arbitrary waveform generation functionality and 4k image/video storage. The ground terminal employs a highly directive Cassegrain antenna with coarse GNSS and fine multi-mode RF tracking and a low-noise receiver together with an integrated high-speed digital processing and storage unit.
-
PublicationComparison of Electronic and Optoelectronic Signal Generation for Wireless THz Communications( 2023)We compare electronic and optoelectronic terahertz (THz) signal generation. By mathematical modeling, we compare the noise performance and show that optoelectronic generation has advantages in terms of linearity and spectral purity but suffers from increased phase noise. For electronic transceiver architectures, however, harmonic mixing terms generated in the mixers as well as intermodulation products can become the limiting factors. We experimentally validate our analytical considerations transmitting QPSK, 8QAM, and 16QAM at symbol rates of up to 8 Gbaud over a distance of up to 48m.
-
PublicationImpairments of Atmospheric Attenuation on a Wideband E-Band Outdoor Communication Link( 2022)This paper analyses experimental data of the atmospheric propagation effects affecting millimeter wave communication links using wideband complex modulation formats with up to 3.3 GBd symbol rate. The main focus is on attenuation caused by atmospheric gases and water droplets and the influence of the air temperature and humidity on an E-band link (71–76 GHz), operated over 1.6 km distance for a period of more than 2 months. Statistics of the expected losses, according to the pertaining International Telecommunication Union models and some experimental results, as in the case of rain and snow attenuation, obtained in Stuttgart, Germany, are discussed and provide further insights in link stability and availability. 3.3 GBd are correctly transmitted regardless of the weather conditions. The presented link can also serve as calibration system for further atmospheric effects studies.
-
PublicationA Superheterodyne 300GHz Transmit Receive Chipset for Beyond 5G Network Integration( 2022)
-
PublicationE-Band Transmitter with 3 W Complex Modulated Signal Output Power Performance( 2022)This paper reports on an E-band transmitter frontend designed to operate on a CubeSat platform to explore high data rate downlink from a low earth orbit. The LO generation, the up-conversion and the RF pre-amplification realized by MMICs based on 50 nm InGaAs metamorphic high electron mobility transistor technology. The final amplification stage comprises two solid-state power amplifier chips, parallelized with waveguide techniques into a single split-block waveguide module, utilizing an AlGaN/GaN-HEMT technology with 100nm gate length. The Tx chain is characterized, both, with single IF tones and wideband complex modulated signals. The transmit frontend achieves a record maximum output power of 3 W for a QPSK modulation with 7.4 Gbit/s data rate, demodulated with a broadband receiver. A maximum QPSK-modulated symbol rate of 6 Gbd could be captured by the signal analyzer software with an EVM of 34% and signal power of 33dBm. In addition higher order modulation formats 16- and 32-QAM are demonstrated.
-
PublicationMeasurements of Atmospheric Attenuation in an Outdoor Wireless E/W-Band Communication Link( 2022)This paper is giving a summary about the atmospheric effects affecting millimeter wave communication systems for a point-to-point E-band link. The focus is on attenuation caused by water droplets. Experimental results obtained in Stuttgart, Germany, are presented to confirm the theoretical aspects discussed through this paper. Wideband complex modulated signals with up to 3.3 GBd symbol rate are used to model the atmospheric behavior of electromagnetic radio frequency signals on an E-band link (71-76 GHz), operated over 1.6 km distance. This paper reviews also the availability and fade margin targets of the new radio links by showing the correlation with the ITU models and recommendations.
-
PublicationOptical Generation and Transmission of mmWave Signals in 5G ERA: Experimental Evaluation Paradigm( 2022)We demonstrate the generation, of a mmWave signal via the injection of an optical frequency comb (OFC) into an integrated tunable dual distributed Bragg reflector (DBR) laser as well as the fiber transmission and the processing of this signal by an optical beamforming network (OBFN). The dual DBR laser is based on a hybrid indium phosphide (InP)-polymer photonic integrated circuit (PIC). Two different cases have been examined in which the microwave signal is centered around 39 GHz and 60 GHz respectively, carrying quadrature amplitude modulation (QAM) formats at 0.5 Gbaud. In this proof-of-concept scenario, the OBFN consists of two optical paths, where the relative true time delay is induced by an optical delay line (ODL). Extensive comparison between the back-to-back (B2B) case and scenarios with transmission over 25 km of standard single-mode fiber (SSMF) has been made using the error-vector magnitude (EVM) and the bit-error ratio (BER) as evaluation criteria. In all cases, error-free transmission was suggested for all QPSK signals, whereas a worst-case EVM of 11.8% was observed for 16-QAM transmission, successfully showcasing the concept's potential. The generated microwave signal's frequency can be set arbitrarily high, provided that high-speed photodetection equipment is available for the detection and down-conversion of the signal. Extension to higher antenna elements (AEs) numbers is straight-forward, relying only on the number of available photodetectors.
-
PublicationA compact 281-319 GHz low-power downconverter MMIC for superheterodyne communication receivers( 2021)
- 1 (current)
- 2
- 3
- 4
- 5