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This paper describes the computer-aided-design (CAD)-assited microwave characterization of coplanar waveguide (CPW) lines formed by ink-jet printed technology on flexible polyethylene terephthalate (PET) substrates. A spacemapping technique is used to link the measured results with simulations and the mapping is used to extract the electrical properties of the ink and supporting dielectric spacer...
This paper describes the computer-aided-design (CAD)-assited microwave characterization of coplanar waveguide (CPW) lines formed by ink-jet printed technology on flexible polyethylene terephthalate (PET) substrates. A spacemapping technique is used to link the measured results with simulations and the mapping is used to extract the electrical properties of the ink and supporting dielectric spacer...
We propose a compact wideband multi-way power divider/combiner with planar structure for applications to RF power amplifiers (PAs). Uniform transmission lines in the conventional divider are replaced with non-uniform transmission lines (NTLs), which are governed by a truncated Fourier series. An optimization-driven framework is employed in even-mode analysis to obtain the coefficients of the NTLs...
An Unequally Spaced Multi-Tone signal (USMT) is used for the assessment of nonlinear devices and circuits. The statistical properties of the signal are described. The setup measurements for such a signal are given either by using a Large Signal Network Analyzer (LSNA) or a Nonlinear Vector Network Analyzer (Keysight PNA NVNA with SA option). A USMT Load Pull (USMT-LP)set-up has been developed using...
Error Vector Magnitude (EVM) is used by communication systems designers as one way to express distortions in digital communications. These distortions may come from initial modulator amplitude and phase imbalances, from linear distortions or non-linear distortions in the transmission chain. It is a good indicator of power amplifiers non-linearity. We propose to use a closed form method based on cross-correlation...
In this contribution we describe the accuracy improvement achievable using a vector corrected, power calibrated test-bench when measuring mm-wave non-linear devices. The absence of automatic level control in commercially available network analyzer frequency extenders can result in AM distortion of the transfer characteristic. Moreover, when largesignal mm-wave test-benches are employed (i.e., using...
As with anything new, especially metrology tools, you want to know how good the new tool is. This is generally done through comparisons with existing systems. In this paper, such a comparison is described. The new NIST method of processing measurements and uncertainties, the Microwave Uncertainty Framework will be compared to the established NIST method for measuring one and two-port scattering-parameters...
We have developed flexible circular dielectric waveguide for millimeter-wave and terahertz frequency applications. In the millimeter and terahertz frequency range, over 70 GHz, metallic waveguide transmission line is generally used. However, it is hard to build-up the system due to noflexibility of metallic waveguide lines. High density polytetrafluoroethylene, i.e. PTFE, is used for developed dielectric...
This paper presents a digitally assisted analogpredistortion scheme for linearization of high power amplifier. Taking advantage of recent available digital signal processing solutions, the proposed method reduces hardware requirement of conventional analog predistorter by alleviating the need of Vector multiplier, hybrid 900 coupler and delay lines. Proposed method provides flexibility in terms of...
This paper reports our precise measurement of a gallium nitride (GaN) schottky diode and our diode model for designing a rectifier at 5.8 GHz. The originality in this study is the estimation of the measurement uncertainty of the GaN diode and its propagation to the diode model, and the calculation of the uncertainty of the parameters in this model. The relative expanded uncertainty (95 % confidence...
In this study, quasi-optical techniques are used to evaluate the properties of dielectric substrates at millimeter wave frequencies. Anisotropy with respect to wave polarization was observed in the composite materials using several instruments including the FTS, TDS, and THz VNA. The measurements were carried out from 200 GHz to 3000 GHz (3 THz ) depending on the instrument. Material loss deviated...
A revealing case study is presented to explore the impact of excess noise ratio (ENR) and vector network analyzer (VNA) mechanical coaxial calibration on accurate on-wafer noise parameter testing for ultra-low noise devices. On-wafer noise parameter tests were conducted on a GaAs pHEMT device from 2-50 GHz after calibration with three different noise sources. For each, ENR specified from an external...
A testbed is reported for the measurement of the instantaneous power dissipation of a dual input Chireix power amplifier (PA) driven by an LTE signal. An FPGA system is used to dynamically control the phase difference and respective incident power level of the two signals injected at the dual-inputs of the Chireix PA under test. The dynamic drain currents of the power amplifier are measured using...
Transmission lines take a crucial role in verifying measurement accuracy of a calibrated vector network analyzer (VNA) as well as in establishing traceability of measured Sparameters. Difficulties in manufacturing of long transmission lines demand verification of the test transmission line before use. This work presents a simple method for comparing characteristic impedance of a test line with the...
This paper presents a scalable MIM capacitor model that is applicable at RF and mm-wave frequencies. The model parameters are obtained from electromagnetic simulations and verified by measurements over a wide range of geometry parameters. A de-embedding method is described that is based on two through structures.
This paper describes the design, fabrication, and testing of an on-wafer substrate that has been developed specifically for measuring extreme impedance devices using an on-wafer probe station. Such devices include carbon nano-tubes (CNTs) and structures based on graphene which possess impedances in the κ Ω range and are generally realised on the nano-scale rather than the micro-scale that is used...
We provide total radiated power measurements at millimeter-wave frequencies using a reverberation chamber and a power-calibrated vector network analyzer capable of measuring wave parameters. We compare total radiated power results obtained from two different approaches. In the first approach, applicable when the terminals of the antenna under test are accessible, the total radiated power is calculated...
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