Two-tier Calibration Research Articles

Modeling of SOL calibration standards for PCB channel probing

On-wafer probes are used to obtain vector network analyzer (VNA) measurements for the close packed PCB channels in the system applications. The S-parameter model of the probes is de-embedded from channel data in a two-tier calibration, which is an efficient option to perform the calibration. The one port method with short-open-load (SOL) standards derives the probe models. Its accuracy relies on the accurate knowledge of the electrical property of the SOL standards used in the calibration. In this paper, the modeling methodology of SOL standards on the calibration substrate is presented. The models for SOL standards are determined empirically by using the measured zero-length thru data as a reference. An optimization algorithm is applied to aid the search of the best models for SOL standards. The standards are also simulated with a 3D full wave field solver to capture the physical aspect of the layout of the standards directly, though it is limited as an approximation.

Estimation of Transferred Power from a Noise Source to an IC with Forwarded Power Characteristics

This paper proposes an accurate approach for predicting transferred power from a noise source to integrated circuits based on the characteristics of the power transfer network. A power delivery trace on a package and a printed circuit board are designed to transmit power from an external source to integrated circuits. The power is demonstrated between an injection terminal on the edge of the printed circuit board and integrated circuits, and the power transfer function of the power distribution network is derived. A two-tier calibration is applied to the test, and scattering parameters of the network are measured for the calculation of the power transfer function. After testing to obtain the indispensable parameters, the real received and tolerable power of the integrated circuits can be easily achieved. Our proposed estimation method is an enhancement of the existing the International Electrotechnical Commission standard for precise prediction of the electromagnetic immunity of integrated circuits.

A NEW QUALITY INDICATOR FOR WIDEBAND UNTERMINATION BY USING REFLECTIVE STANDARDS

In this paper a new quality indicator for two-tier calibration procedures that use only reflection standards is presented and applied to coaxial-to-waveguide transitions. The quality indicator is based on the algebraic conditioning of the system of equations solved for obtaining transition characteristics. The study has been carried out in a wide bandwidth as a difference with previous works. The obtained results indicate that a threshold value for this indicator around 10% can be established. For values below this limit the error grows to unacceptable values. Additionally, it has been shown that an exponential relationship between quality indicator and the error can be predicted.

Electrical Performance of the Recessed Probe Launch Technique for Measurement of Embedded Multilayer Structures

This paper explores the electrical performance of a recessed probe launch (RPL) technique for measurement of embedded (internal) printed circuit board (PCB) structures such as striplines and vias (plated through holes). The RPL uses high-frequency microprobes in combination with a milling technique that removes upper board layers and exposes internal probing points. A two-tier calibration technique is applied for the extraction of the S-parameters of the RPLs with the help of thru-reflect-line calibration standards designed on PCB. Full-wave models are used to corroborate and validate the obtained S-parameters. Good model-to-hardware correlation is obtained up to 40 GHz. Furthermore, the launch performance with respect to microprobe positioning and variations of the cavity size is investigated using the full-wave models. These simulations suggest techniques for launch optimization and probe modifications that improve the launch measurement bandwidth.

16-Term Error Model in Reciprocal Systems

By taking reciprocity of the error network into account, full and accurate calibration of a 16-term error model can be performed using only four two-port calibration standards or termination pairs. Moreover, there is no need for a nonsymmetrical calibration standard that is strictly required in a more conventional five-standard calibration. Commercially available standard substrates can thus be used. Detailed theory of the reciprocal 16-term error model and a new calibration method are presented. Reciprocity assumption is valid in on-wafer and other measurements when two-tier calibration is applied. However, the calibration scheme allows measurement of nonreciprocal devices too. The usefulness of the new method is confirmed by practical wideband on-wafer measurements.

Novel Wideband Transition Between Coplanar Waveguide and Microstrip Line

A novel wideband vertical transition for connecting the coplanar waveguide (CPW) to the microstrip line is proposed. This transition can be very useful for millimeter-wave packaging and vertical interconnects. It is multilayered, partly tapered, and consists of only one via interconnect. Two different transitions are designed. The first transition allows connectivity of a CPW with Zc=50 Ω to a microstrip line with Zc=16 Ω with a bandwidth of 10-60 GHz. The second transition has the same characteristic impedance, Zc=50 Ω, at the two ports. In this case, the operating frequency is from 40 MHz to 60 GHz. The return losses of both transitions are generally lower than -10 dB over their indicated frequency ranges, while the maximum measured insertion losses are 1.8 and 2.4 dB for the first and second transition, respectively. To extract the S-parameters of the transitions, a new thru-line technique, based on the standard thru-reflect-line two-tier calibration is introduced. Simulation and experimental results, showing good agreement, are presented and discussed.

Extended Through-Short-Delay Technique for the Calibration of Vector Network Analyzers With Nonmating Waveguide Ports

The extension of the through-short-delay (TSD) technique to the calibration of two-port vector network analyzers (VNAs) with nonmating waveguide ports is reported. The method retains the well-known high accuracy of the basic TSD technique while it enables to calibrate VNAs using two waveguide ports with different cross sections. Comparisons with the reciprocal-short-open-load technique commonly adopted to calibrate VNAs with nonconnectable ports and with theoretical data are reported. The present method can be adopted as either a one- or a two-tier calibration technique.

A bilateral lightwave network analyzer-architecture and calibration

The first bilateral lightwave network analyzer (BLNA) architecture that is capable of two-port S-parameter measurements is reported in this paper. A combined two-tier calibration is proposed and implemented for electrooptic and optoelectronic measurements. Calibrated measurement results showing the good performance of the BLNA for all types of lightwave components are also presented.