Marco Dietz

A 4–32-GHz Chipset for a Highly Integrated Heterodyne Two-Port Vector Network Analyzer

This work presents a chipset for a highly integrated heterodyne vector network analyzer (VNA) with two ports and a multi-octave bandwidth from 4 to 32 GHz. The chipset is comprised of a stimulus integrated circuit (IC) with two selectable single-ended output channels and a four-channel receiver IC. Both chips contain a frequency synthesizer with an average output power of 2.5 dBm and a single-sideband phase noise between -96.3 and -115.3 dBc/Hz at 1-MHz offset. The synthesizer consists of an array of three voltage-controlled oscillators with tuning ranges between 24.8% and 28.2% and a bandwidth extension stage. Wideband design techniques based on cascaded emitter followers are applied to a variable gain amplifier with a peak gain of 15.1 dB and to a wideband source switch with a minimum isolation of 23.6 dB. Single-ended receiver components such as a wideband low-noise amplifier with an average gain of 10 dB and a micromixer are used to compose the four-channel receiver with an average conversion gain of 14.4 dB. A hybrid microwave integrated circuit was fabricated in order to prove the functionality of a VNA utilizing the proposed chipset and wideband directional couplers. The measured scattering parameters of an arbitrary device-under-test showed an average deviation of 0.18 dB in magnitude and 1.8 ° in phase from the measurements obtained with a commercial VNA.

Highly Integrated 4-32-GHz Two-Port Vector Network Analyzers for Instrumentation and Biomedical Applications

This paper addresses the miniaturization of microwave vector network analyzers (VNAs) and the future vision of the VNA on a chip. Therefore, a highly integrated two-port VNA with a multioctave bandwidth from 4 to 32 GHz is presented. The proposed system is based on a fully integrated radio-frequency frontend consisting of a two-port stimulus, a four-channel heterodyne receiver, and a wideband testset. The testset is comprised of on-chip multisection directional couplers. The chip is operated inside a hardware demonstrator using a 16-term calibration procedure. The measurement of arbitrary devices under test is in excellent agreement with commercial measurement equipment and showed a mean deviation from the reference measurement of 0.17 dB and 1.29° regarding the forward transmission of a coaxial 30-dB attenuator. The system and receiver dynamic ranges are 44–77 and 82–101 dB at a resolution bandwidth of 100 kHz over the full system bandwidth. The measurements are highly repeatable and are robust against drift over time. As a proof of concept, the developed integrated network analyzers are utilized in a biomedical sensing scenario with an external and an on-chip sensor. Both approaches showed good sensitivity regarding the mixture ratio of binary solutions of ethanol and methanol.

A 10 Gb/s highly-integrated adaptive pseudo-noise transmitter for biomedical applications

A highly-integrated 211 −1 pseudo-random bit sequence (PRBS) transmitter for biomedical applications is presented. The chip consists of an ultra-wideband synthesizer with an integrated divider to drive a PLL, a linear feedback shift register (LFSR) to generate an M-sequence and a programmable binary divider to enable adaptive subsampling technique in the signal processing path. The circuit is created to be used in a miniaturized portable PRBS based sensor system for biomedical applications. A conceivable application is the measurement of dehydration in a human body. The PRBS generator is capable of generating a bit-rate up to 10Gb/s, correlating to a maximum bandwidth of the generated sequence of 5GHz, which is sufficient for the designated applications. The circuit is manufactured in an 0.35 μm SiGe-Bipolar technology with an ft of 200GHz using 12mm2 chip area.

A 60-GHz low-noise variable-gain amplifier in a 130-nm BiCMOS technology for sixport applications

A monolithic low noise variable gain amplifier (LNA) operating at 60 GHz is presented. It is designed for a sixport receiver, which is completely integrated on a single chip. These chips are build in highly miniaturized sensors to measure distances with radar. Therefore a high performance LNA is indispensable. The circuit has been designed using a new 0.13 μm SiGe BiCMOS process from IHP (SG13G2). For implementation a three stage architecture is chosen. Measurements show a tuneable gain from 16 to 24 dB at 60 GHz, an input matching of −17 dB and an output matching of −14 dB. The circuit consumes 13 mA from a 3.3 V supply.

A Low-Power 120-GHz integrated sixport receiver front-end with digital adjustable gain in a 130-nm bicmos technology

In this paper a 120 GHz monolithic low-power sixport receiver front-end including two variable gain amplifiers, a passive sixport network, four detectors and a digital serial interface (SPI) is presented. The measurement principle is based on the additive superposition of two incident millimeter-wave signals, whereas the superposition must be fulfilled under special conditions. After power detection, the quadrature components can be extracted. The proposed measurement system is well suited for industrial radar applications, as well as for biomedical applications and it is further more well suited for communication systems. The receiver has been designed using a 0.13 μm SiGe BiCMOS process from IHP (SG13G2). The whole integrated circuit has a size of 1560 μm × 900 μm and only consumes 102.3 mW from a 3.3 V supply. The receiver exhibits a 1 dB compression point of −13 dBm at the center frequency. The bandwidth is 15.5 GHz and covers the lower part of the D-Band. The gain of the input amplifier can be adjusted from 3 to 16 dB by a digital interface. The maximum power consumption of the VGA is 46.2 mW.

Determination of changes in NaCl concentration in aqueous solutions using an M-sequence based sensor system

In this paper measurements of changes in NaCl concentration in aqueous solutions are presented. For these measurements a simplified pseudo random binary sequence (PRBS) based sensor system, which is based on the binary noise theorem, is used. The pseudo random noise signal is represented by an M-sequence with a bandwidth of 10GHz. The transfer functions of the sensor with different NaCl concentrations in a fixed tube of a contactless distributed probe are determined and compared to each other. The results show that there is a frequency range with a clear relation between the magnitude of the transfer function and the NaCl concentration. This demonstrates, that it is possible to measure changes in NaCl concentration of aqueous solutions with a PRBS based sensor system.

A 180 GHz frequency multiplier in a 130nm SiGe BiCMOS technology

An integrated analog frequency multiplier for a novel high data rate communication system has been developed to multiply a 18GHz input signal by ten to generate a 180 GHz output signal. With a first step the 18GHz input signal is fed into a times five edge combiner, which generates an intermediate frequency of 90 GHz. Therefore five different phases with a delta of 72 degree are needed, that are provided by an active allpass filter chain. In a second step the 90 GHz intermediate frequency is given into a double-balanced Gilbert cell mixer. Here, frequency doubling is achieved by feeding the same signal into the LO and RF port of the mixer. Hence, the overall output frequency of 180GHz results in 180 GHz with a simulated output power of -7 dBm. All simulations are done post-layout. The chip is implemented in a 130nm BiCMOS technology with a chip area of 0.9mm × 1 mm.