Over-the-air (OTA) measurements are the standardized methods to evaluate radio performance in wireless systems. EMC issues such as interference and receiver desensitization are important factors. In this paper, OTA measurement challenges in the upcoming fiftth generation (5G) wireless systems are overviewed. Several key technologies that could be widely used in the 5G OTA measurements are discussed, including near-field to far-field transformation, anechoic chamber absorbers, and sampling antennas. The most important devices under test (DUT) for 5G OTA are chip sets, user equipment, and active array systems. The OTA test challenges for certification, research and development, and mass production for these DUTs are introduced.

Through silicon via (TSV)-based 3-D integrated circuit has introduced the solution to limitlessly growing demand on high system bandwidth, low power consumption, and small form factor of electronic devices. As the system design aims for higher performance, the physical dimensions of the channels are continuously decreasing. With TSV diameter of less than 10 μm and pitch of several tens of micrometers, the I/O count has increased up to the order of tens of thousands for wide bandwidth data transmission. However, without highly precise fabrication process, such small structures are susceptible to a variety of defects. For the first time, in this paper, we propose a noninvasive defect analysis method for high-speed TSV channel. With designed and fabricated test vehicles, the proposed method is demonstrated with S-parameter and time-domain reflectometry measurement results. In addition, we present equivalent circuit models of TSV daisy-chain structures, including the circuit components for open defect and short defect. With characterized dominant factors in each frequency range, S ₁₁ is analyzed to distinguish and locate the defects by the amount of capacitance, resistance, and inductance that the signal experiences. S-parameter measurement sufficiently allows high-frequency defect analysis of TSV channel without destroying the test sample. We experimentally verified the accuracy of the suggested model by comparing the S-parameter results from circuit simulations and measurements. Finally, the model is modified to discuss the effects of open defect and short defect on the electrical characteristics of TSV channel.

The aim of this paper is to present a novel and compact transmit/receive module (TRM) for enhancing antenna performances to be employed in space applications. The key advancement is the use of a 3-D technology which, to the best of our knowledge, would be for the first time introduced in the space industry for hermetically packaging RF modules. The 3-D module development is based on the highly demanding specifications of space active electronically steerable antennas (AESAs); the TRM consists of two ``submodules'' electrically connected by an ad hoc interposer. The complete electrical design process, together with a comprehensive discussion on electromagnetic, mechanical, and thermal aspects, is presented, and the achieved module performances such as gain and return losses are detailed. Moreover, several manufactured samples are measured to validate the simulated design, and the excellent results in terms of gain, noise figure, and output power fulfilling the target specs are presented and discussed. The presented data, characterized by a limited variability among the 10 measured samples, make the proposed design and the manufacturing process a good candidate in terms of potential reliability for building the next generation of high-performance space AESA.

This contribution deals with the optimal placement of the decoupling capacitances on the gridded power delivery network of a multichip assembly with interposer. The optimization is performed by means of a nature-inspired algorithm of the genetic class. Different placement strategies are considered and compared. The cost function is based on the evaluation of the input impedance looked into the power and ground rails of the power distribution network and its comparison with a user-defined mask.

An iterative optimization for decoupling capacitor placement on a power delivery network (PDN) is presented based on Genetic Algorithm (GA) and Artificial Neural Network (ANN). The ANN is first trained by an appropriate set of results obtained by a commercial simulator. Once the ANN is ready, it is used within an iterative GA process to place a minimum number of decoupling capacitors for minimizing the differences between the input impedance at one or more location, and the required target impedance. The combined GA–ANN process is shown to effectively provide results consistent with those obtained by a longer optimization based on commercial simulators. With the new approach the accuracy of the results remains at the same level, but the computational time is reduced by at least 30 times. Two test cases have been considered for validating the proposed approach, with the second one also being compared by experimental measurements.

A new common-mode filter structure based on planar electromagnetic bandgap (EBG) technologies is designed, fabricated, and measured. It is based on a previously proposed geometry, implementing a sequence of two or more EBGs resonating at a filtering frequency; however, the new filter is placed on the top of the PCB as a standalone component, instead of being included within the PCB stack up. The filter can be easily removed and substituted by another one that is designed to filter a different frequency. The replacement design should maintain the same external size of the component as the original filter, which can be achieved by choosing the permittivity of the dielectric as well as the relationship among the EBG parameters appropriately. The electromagnetic behavior of the filter is simulated and a prototype structure is fabricated and measured. Results are compared to validate the design concept and procedure.