Wolfgang Bosch | Graz University of Technology (original) (raw)

Papers by Wolfgang Bosch

2020 International Workshop on Antenna Technology (iWAT), 2020

In this paper, a slotted substrate integrated waveguide (SIW) beamforming phased array antenna is... more In this paper, a slotted substrate integrated waveguide (SIW) beamforming phased array antenna is investigated. The phased array antenna is fed by a highly integrated Quadchannel RX/TX Ka-band time delay beamforming RFIC. The proposed antenna is 64-element slot array antenna built in three-layer printed circuit board which are connecting through a Microstrip-Coaxial-Microstrip (MCM) transition with surrounding metallic via-holes. Different MCM topologies are investigated through a pervasive parameter studies. The proposed antenna is operating at 30-GHz with bandwidth of 1.4 GHz (-10-dB return loss) and directivity of 15.6 dBi.

2021 IEEE Radio and Wireless Symposium (RWS)

In this paper, we present a novel equivalent circuit (EC) model that can be used to conduct a cir... more In this paper, we present a novel equivalent circuit (EC) model that can be used to conduct a circuit-level interoperability analysis of a wireless power transfer (WPT) system and a near-field communication (NFC) system in close proximity to one another. Each system consists of two devices, which are respectively the WPT transmitter, WPT receiver, NFC reader, and NFC transponder (tag). Due to their close proximity, the WPT and the NFC systems interact with one another due to parasitic inductive and capacitive coupling between their coil antennas. Our investigations show that parasitic coupling causes the NFC system to produce a distorted communication signal. In particular, the detectability of the communication signal sent from the NFC tag to the NFC reader decreases rapidly, if the parasitic capacitive coupling between the coil antennas is too large. In addition, a custom-built prototype is presented here that can be used to take measurements and verify these results.

2020 International Workshop on Antenna Technology (iWAT)

This paper introduces a new design methodology of filtering antenna (filtenna) based on the coupl... more This paper introduces a new design methodology of filtering antenna (filtenna) based on the coupled radiating resonator structure. The idea is to integrate both filter and antenna as a single component with combined treatment. The patch antenna structure backed by substrate integrated cavity (SIC) resonator is effectively employed to comply with coupled-resonator filtering function. The proposed filtenna is a compact stack-layered array antenna module with the aim of highly integrated 5G massive array antenna application. A fourth-degree filtenna with operating frequency band of 27-29 GHz and return loss better than 22-dB is designed to verify the design method. The simulated results are in good agreement compared with those of analytical synthesis and circuit model.

For space applications an accurate estimate of the GaAs-FET lifetime is fundamental as it has a s... more For space applications an accurate estimate of the GaAs-FET lifetime is fundamental as it has a significant impact on the overall system design. The gate current is one of the most sensitive parameters regarding degradation modes, hence its behaviour under RF operation is a valid measure for lifetime. Different degradation and failure modes are analyzed and presented. The stress on the device under multicarrier operation when CW reliability data are available is simulated by means of a simplified amplifier model and the statistical properties of the applied RF signals.

A shaping network of beams (CFH ") comprising circuits operating a Discrete Fourier Transfor... more A shaping network of beams (CFH ") comprising circuits operating a Discrete Fourier Transform" DFT "two-dimensional hexagonal on input signals so as to control the radiating elements of an antenna. The number of inputs being equal to Nt, with Nt = N ** 2xR, the circuitry comprises a first layer (5) consists of N identical cells (51a-54d) operating a "DFT" dimensional RxR and a second layer consisting of R games independent (7, 8, 9), each set including first (71-74, 81-84, 91-94) and second (75-78, 85-88, 95-98) of N identical cells rows operating a " DFT "dimensional NxN. the invention also relates to the mechanical layout structure of such a network (CFH"). Application particularly to the control of radio frequency antennas of the network type to the control phase for generating multiple beams, embedded on a satellite .

2016 Austrochip Workshop on Microelectronics (Austrochip), 2016

Circuit techniques termed as threshold voltage (Vth) compensation are utilized for CMOS RF-DC pow... more Circuit techniques termed as threshold voltage (Vth) compensation are utilized for CMOS RF-DC power converters or more specifically RF charge pumps to improve the power conversion efficiency at low levels of RF input voltage. In this work, we present two differential RF charge pumps for UHF RFID transponder ICs that include a Vth compensation. The first circuit uses gate biasing for Vth compensation, whereas the second circuit design follows a combined approach of gate and bulk biasing. The circuits have been manufactured in a 40nm low-power CMOS technology. Measurement results demonstrate that the power conversion efficiency can be improved from 39% to 42% at a given output power of 4µW and an output voltage of 1V by using bulk biasing. Both circuits show a low input quality factor of 13 at this output power level and allow therefore the implementation of highly sensitive broadband UHF RFID transponders.

IEEE Transactions on Microwave Theory and Techniques, 1989

Ahsfrucf-A typical method for designing a predistortion linearizer is to realize a circuit that c... more Ahsfrucf-A typical method for designing a predistortion linearizer is to realize a circuit that creates an AM/AM and AM/PM characteristic inverse to that of the power amplifier to be linearized [1]-[3]. This strategy is correct only if the predistortion circuit maintains this characteristic also at signal envelope frequencies. This is often not true due to the time constants present in the linearizer circuits that limit its effectiveness (hereafter these effects are referred as memory effects). This problem is not limited to linearization techniques hut affects the operation of nonlinear systems in general. The purpose of this paper is to review the major consequences of memory effects, to present efficient techniques to measure them, and to illustrate a simulation approach that can be used to predict their influence in practical systems.

2017 47th European Microwave Conference (EuMC), Oct 1, 2017

A new class of dual-mode dual-band microwave filters is presented. Conductor-loaded dielectric re... more A new class of dual-mode dual-band microwave filters is presented. Conductor-loaded dielectric resonators are used as a basic building blocks for these devices. The proposed resonator enables the realization of microwave filters with unloaded quality factors of 1000-4000 with good spurious performance and significant reduced size, e.g. less than the half physical size, compared to TEM filters. The basic properties of the proposed resonator have been studied and examined with the help of a finite element method solver (HFSS2015). A design example of a dual-mode dual-band bandpass filter with maximum transmission zeros for mobile communications is developed.

e & i Elektrotechnik und Informationstechnik

More and more driver assistance systems are integrated into modern vehicles. This development res... more More and more driver assistance systems are integrated into modern vehicles. This development results in a continuous rise in the complexity of these vehicles, as the functions have to comply to the corresponding safety standards. Testing and validating these functions on an automotive test bench instead of driving tests at closed proving grounds requires comprehensive stimulation of the involved sensors. In this article we are focusing on an approach for stimulating short-range radar sensors of a vehicle located on such a test bench. Coping with the requirements imposed by these types of sensors we investigate the usage of frequency multipliers and dividers in the frequency translation section of the radar stimulator. For this purpose, we provide an overview on different concepts for these multipliers and dividers. After reviewing the advantages and disadvantages of these devices, we provide measurement results of a stimulator setup applying this type of frequency translation.

IEEE Transactions on Microwave Theory and Techniques

This paper presents a new class of triple mode dielectric resonator filters. These devices use di... more This paper presents a new class of triple mode dielectric resonator filters. These devices use dielectric-loaded cavities with unloaded Q-factor of 3000-5000 and reasonable spurious free window. The proposed structure is less than one quarter of the physical volume of TEM filters of the same Q. A finite element method solver for electromagnetic structures (HFSS) is used to study the main properties of this resonator. Fundamental design rules for a bandpass filter have been presented. A three pole bandpass filter was designed, fabricated and measured to verify the proposed approach.

2016 11th European Microwave Integrated Circuits Conference (EuMIC), 2016

2016 International Conference on Broadband Communications for Next Generation Networks and Multimedia Applications (CoBCom), 2016

2015 IEEE MTT-S International Microwave Symposium, 2015

IEEE Transactions on Microwave Theory and Techniques

IEEE Transactions on Microwave Theory and Techniques

2013 European Microwave Conference, 2013

2013 35th Electrical Overstress Electrostatic Discharge Symposium, Sep 1, 2013

2020 International Workshop on Antenna Technology (iWAT), 2020

In this paper, a slotted substrate integrated waveguide (SIW) beamforming phased array antenna is... more In this paper, a slotted substrate integrated waveguide (SIW) beamforming phased array antenna is investigated. The phased array antenna is fed by a highly integrated Quadchannel RX/TX Ka-band time delay beamforming RFIC. The proposed antenna is 64-element slot array antenna built in three-layer printed circuit board which are connecting through a Microstrip-Coaxial-Microstrip (MCM) transition with surrounding metallic via-holes. Different MCM topologies are investigated through a pervasive parameter studies. The proposed antenna is operating at 30-GHz with bandwidth of 1.4 GHz (-10-dB return loss) and directivity of 15.6 dBi.

2021 IEEE Radio and Wireless Symposium (RWS)

In this paper, we present a novel equivalent circuit (EC) model that can be used to conduct a cir... more In this paper, we present a novel equivalent circuit (EC) model that can be used to conduct a circuit-level interoperability analysis of a wireless power transfer (WPT) system and a near-field communication (NFC) system in close proximity to one another. Each system consists of two devices, which are respectively the WPT transmitter, WPT receiver, NFC reader, and NFC transponder (tag). Due to their close proximity, the WPT and the NFC systems interact with one another due to parasitic inductive and capacitive coupling between their coil antennas. Our investigations show that parasitic coupling causes the NFC system to produce a distorted communication signal. In particular, the detectability of the communication signal sent from the NFC tag to the NFC reader decreases rapidly, if the parasitic capacitive coupling between the coil antennas is too large. In addition, a custom-built prototype is presented here that can be used to take measurements and verify these results.

2020 International Workshop on Antenna Technology (iWAT)

This paper introduces a new design methodology of filtering antenna (filtenna) based on the coupl... more This paper introduces a new design methodology of filtering antenna (filtenna) based on the coupled radiating resonator structure. The idea is to integrate both filter and antenna as a single component with combined treatment. The patch antenna structure backed by substrate integrated cavity (SIC) resonator is effectively employed to comply with coupled-resonator filtering function. The proposed filtenna is a compact stack-layered array antenna module with the aim of highly integrated 5G massive array antenna application. A fourth-degree filtenna with operating frequency band of 27-29 GHz and return loss better than 22-dB is designed to verify the design method. The simulated results are in good agreement compared with those of analytical synthesis and circuit model.

For space applications an accurate estimate of the GaAs-FET lifetime is fundamental as it has a s... more For space applications an accurate estimate of the GaAs-FET lifetime is fundamental as it has a significant impact on the overall system design. The gate current is one of the most sensitive parameters regarding degradation modes, hence its behaviour under RF operation is a valid measure for lifetime. Different degradation and failure modes are analyzed and presented. The stress on the device under multicarrier operation when CW reliability data are available is simulated by means of a simplified amplifier model and the statistical properties of the applied RF signals.

A shaping network of beams (CFH ") comprising circuits operating a Discrete Fourier Transfor... more A shaping network of beams (CFH ") comprising circuits operating a Discrete Fourier Transform" DFT "two-dimensional hexagonal on input signals so as to control the radiating elements of an antenna. The number of inputs being equal to Nt, with Nt = N ** 2xR, the circuitry comprises a first layer (5) consists of N identical cells (51a-54d) operating a "DFT" dimensional RxR and a second layer consisting of R games independent (7, 8, 9), each set including first (71-74, 81-84, 91-94) and second (75-78, 85-88, 95-98) of N identical cells rows operating a " DFT "dimensional NxN. the invention also relates to the mechanical layout structure of such a network (CFH"). Application particularly to the control of radio frequency antennas of the network type to the control phase for generating multiple beams, embedded on a satellite .

2016 Austrochip Workshop on Microelectronics (Austrochip), 2016

Circuit techniques termed as threshold voltage (Vth) compensation are utilized for CMOS RF-DC pow... more Circuit techniques termed as threshold voltage (Vth) compensation are utilized for CMOS RF-DC power converters or more specifically RF charge pumps to improve the power conversion efficiency at low levels of RF input voltage. In this work, we present two differential RF charge pumps for UHF RFID transponder ICs that include a Vth compensation. The first circuit uses gate biasing for Vth compensation, whereas the second circuit design follows a combined approach of gate and bulk biasing. The circuits have been manufactured in a 40nm low-power CMOS technology. Measurement results demonstrate that the power conversion efficiency can be improved from 39% to 42% at a given output power of 4µW and an output voltage of 1V by using bulk biasing. Both circuits show a low input quality factor of 13 at this output power level and allow therefore the implementation of highly sensitive broadband UHF RFID transponders.

IEEE Transactions on Microwave Theory and Techniques, 1989

Ahsfrucf-A typical method for designing a predistortion linearizer is to realize a circuit that c... more Ahsfrucf-A typical method for designing a predistortion linearizer is to realize a circuit that creates an AM/AM and AM/PM characteristic inverse to that of the power amplifier to be linearized [1]-[3]. This strategy is correct only if the predistortion circuit maintains this characteristic also at signal envelope frequencies. This is often not true due to the time constants present in the linearizer circuits that limit its effectiveness (hereafter these effects are referred as memory effects). This problem is not limited to linearization techniques hut affects the operation of nonlinear systems in general. The purpose of this paper is to review the major consequences of memory effects, to present efficient techniques to measure them, and to illustrate a simulation approach that can be used to predict their influence in practical systems.

2017 47th European Microwave Conference (EuMC), Oct 1, 2017

A new class of dual-mode dual-band microwave filters is presented. Conductor-loaded dielectric re... more A new class of dual-mode dual-band microwave filters is presented. Conductor-loaded dielectric resonators are used as a basic building blocks for these devices. The proposed resonator enables the realization of microwave filters with unloaded quality factors of 1000-4000 with good spurious performance and significant reduced size, e.g. less than the half physical size, compared to TEM filters. The basic properties of the proposed resonator have been studied and examined with the help of a finite element method solver (HFSS2015). A design example of a dual-mode dual-band bandpass filter with maximum transmission zeros for mobile communications is developed.

e & i Elektrotechnik und Informationstechnik

More and more driver assistance systems are integrated into modern vehicles. This development res... more More and more driver assistance systems are integrated into modern vehicles. This development results in a continuous rise in the complexity of these vehicles, as the functions have to comply to the corresponding safety standards. Testing and validating these functions on an automotive test bench instead of driving tests at closed proving grounds requires comprehensive stimulation of the involved sensors. In this article we are focusing on an approach for stimulating short-range radar sensors of a vehicle located on such a test bench. Coping with the requirements imposed by these types of sensors we investigate the usage of frequency multipliers and dividers in the frequency translation section of the radar stimulator. For this purpose, we provide an overview on different concepts for these multipliers and dividers. After reviewing the advantages and disadvantages of these devices, we provide measurement results of a stimulator setup applying this type of frequency translation.

IEEE Transactions on Microwave Theory and Techniques

This paper presents a new class of triple mode dielectric resonator filters. These devices use di... more This paper presents a new class of triple mode dielectric resonator filters. These devices use dielectric-loaded cavities with unloaded Q-factor of 3000-5000 and reasonable spurious free window. The proposed structure is less than one quarter of the physical volume of TEM filters of the same Q. A finite element method solver for electromagnetic structures (HFSS) is used to study the main properties of this resonator. Fundamental design rules for a bandpass filter have been presented. A three pole bandpass filter was designed, fabricated and measured to verify the proposed approach.

2016 11th European Microwave Integrated Circuits Conference (EuMIC), 2016

2016 International Conference on Broadband Communications for Next Generation Networks and Multimedia Applications (CoBCom), 2016

2015 IEEE MTT-S International Microwave Symposium, 2015

IEEE Transactions on Microwave Theory and Techniques

IEEE Transactions on Microwave Theory and Techniques

2013 European Microwave Conference, 2013

2013 35th Electrical Overstress Electrostatic Discharge Symposium, Sep 1, 2013