J.-M. Heinola

A Review of Microstrip T-resonator Method in Determination of Dielectric Properties of Printed Circuit Board Materials

When designing devices at microwave frequencies, the characteristics of printed circuit board materials should be well known in order to attain exact functionality. The characterization can be carried out for example with T-resonator test method. In this paper, microstrip T-resonator test method is analyzed. The analysis is based on literature search and experimental research, and the practicable calculation methods are introduced. The introduced modifications provide more precise calculation improving the accuracy of the method. The modifications also enable the determination of dielectric properties of high loss printed circuit board materials at broad frequency and temperature ranges

Dielectric characterization of printed wiring board materials using ring resonator techniques: a comparison of calculation models

Ring resonator structures are widely used to characterize the frequency and temperature dependence of the relative permittivity and loss tangent of printed wiring board materials. Several theoretical models for the ring resonator structures have been presented since the first ring resonator application. In this paper, the theoretical models of the ring resonator structure are adapted for calculating the relative permittivity of low-loss and high-loss printed wiring board materials at frequency range from 250 MHz to 10.0 GHz. In addition, a review of the characterization of the loss tangent using the ring resonator is presented. The review also provides information about differences of the results due to different approximation used for conductor losses of the microstrip line. The research presented in this paper is based on an experimental research with several different microstrip and strip line ring resonator structures. The results of this study provide useful information about applying the ring resonator method for measuring the relative permittivity and loss tangent of dielectric substrates

A new method to measure dielectric constant and dissipation factor of printed circuit board laminate material in function of temperature and frequency

In this article, a new method to measure the values of dielectric constant and dissipation factor of printed circuit board laminate material in function of temperature and frequency is presented. The method is based on the use of microstrip ring resonator structures and a climate chamber. The presented method is experimentally tested at frequency range from 1 GHz to 10 GHz and at the temperature range from -30/spl deg/C to 105/spl deg/C. With the presented method, frequency properties of different laminate materials and coatings can be measured at wide frequency and temperature range.

Determination of dielectric constant and dissipation factor of a printed circuit board material using a microstrip ring resonator structure

A microstrip ring resonator structure is used to determine the dielectric constant and dissipation factor of FR-4 type printed circuit board material. The article presents essential information on the microstrip ring resonator measurement method, characteristics of the microstrip line losses, and dielectric constant and dissipation factor calculation techniques. Based on the presented information, the dielectric properties of high loss printed circuit board materials can be determined for a wide frequency band.

A strip line ring resonator method for determination of dielectric properties of printed circuit board material in function of frequency

A new approach to determine dielectric properties of printed circuit board materials is presented. The new method is based on the use of a strip line ring resonator structure and utilization of the thru-reflect-line calibration method. An experimental research was carried out with one FR-4 type material in a frequency range from 1.0 GHz to 10.0 GHz and in a temperature range from -35/spl deg/C to 105/spl deg/C. The method was noted to be applicable for determination of dielectric properties as a function of frequency and temperature.

A method to evaluate effects of moisture absorption on dielectric constant and dissipation factor of printed circuit board materials

In this article a new method to evaluate, effects of moisture absorption on dielectric constant and dissipation factor in function of temperature and frequency are presented. The development of method is based on the experimental measurements and the use of ring resonator structures implemented to FR4-type material. The experimental measurement procedure was carried out at frequency range from 1 GHz to 10 GHz. The used temperature points were 23/spl deg/C and 85/spl deg/C. The results gained by the presented method were observed to be reproducible and consistent with the amount of the absorbed moisture. The method can be applied to different printed circuit board materials.

Dielectric characterization of printed wiring board materials: a comparison of ring and T-resonator based measurement methods

Dielectric characterization of printed wiring board materials is important for ensuring designed performance of printed wiring board products. Ring and T-resonator type planar transmission line resonators are widely used for dielectric characterization of printed wiring board materials. The measurement methods that are based on the ring and T-resonators are both broadband and the direction of the electric field is normal to a face of a measurement sample. A comparison between the ring and T-resonator based methods is presented in this article. The comparison is based on an experimental research that is carried out with one FR-4 type printed wiring board material at wide frequency range. The results of the comparison prove that with the ring and T-resonator based measurement methods can be achieved similar results in dielectric characterization of FR-4 type printed wiring board materials.

Effects of dimensions variation to the results of microstrip ring resonator method used on determination of dielectric properties

In this article, effects of dimension variation of the microstrip ring resonator structure to the determination results are experimentally studied. A measurement structure is presented, which includes several two-port microstrip ring resonators. The basic idea behind the determination of valued of dielectric constant is to design the microstrip line ring resonator structure to a certain main resonance frequency. The design is based on an estimated value of dielectric constant. If the measured resonance frequency deviates from the theoretically calculated value, the actual value of the material dielectric constant deviates from the estimated basing on the measured resonance frequencies and the dimensions of the microstrip line ring resonator structure. Determination of values of loss tangent in function of frequency is based on measured value of the loaded quality factor Q 1 and calculated value of the unloaded quality factor Q1 at each resonance frequency

Use of harmonics of microstrip ring resonator structure on determination of dielectric properties

Dielectric properties of printed wiring boards play a key role in many antenna application designs. The focus of this paper is to study effects of the harmonics of the ring resonator to determination uncertainty. For this purpose an experimental research of harmonics of the microstrip ring resonator is carried out. Results of the research offer essential information about determination of dielectric properties by using microstrip ring resonator structures.

Manufacturability aspects of a feeding pin construction in a coaxial to waveguide transition

Manufacturability aspects of a feeding pin in a coaxial to waveguide transition is discussed and various constructions are studied. Four SMA connector-based feeding pin geometries are constructed to find out how critical is the construction of the transition feeding pin. The reflection coefficient of the coaxial to waveguide transition of a horn antenna construction is measured with different feeding pins. Feeding pins are analyzed to find a construction with both good manufacturability and good electrical properties.