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RF transceiver module is considered a vital part of any wireless communication system. This module consists of two important parts the RF transceiver and analog-to-digital converter (ADC). Usually, both these parts – RF transceiver and ADC – are used to enhance the perspective of size and power. The data processing in 4G communication makes hurdles and need research attention to make it faster and smaller in size. Accuracy and fast processing are the critical challenges in the modern communication system.

After theoretical and practical investigations, this research work proposes key new techniques for the RF transceiver module. These techniques will make RF transceiver small, power-efficient and on the other hand, make dual SAR-ADC more effective as well. The proposed design has no intermediate frequency where the RF transceiver is reduced its major blocks from five to four, which includes crystal oscillator, phase lock loop, power amplifier and low noise amplifier. Moreover, the shared circuitry is introduced in the architecture of the SAR-ADC for the production of dual outputs, specifically in bootstrapped switch and comparator.

The miniaturized RF transceiver and SAR-ADC are well tested separately before the plantation on the printed circuit board (PCB). The operating voltage and frequency of the RF transceiver module are 1.2 V and 5.8 GHz, where the sampling rate, bandwidth and output power are 25 MHz, 200 MHz and 5 dBm, respectively. The core area of the PCB is 58.13 mm². The bandwidth efficiency is 93% using surface acoustic wave less transmitter. The circuit is based on the library of 90 nm CMOS technology.

The entire circuit is highly synchronized with the input and reference clocks to avoid self-interference.

A W-band antennas-in-packages (AIP) module with a hybrid stacked glass-compound wafer level fan-out process was presented. Heterogeneous radio frequency (RF) chips were integrated into one single module with a microscale fan-out process. This paper aims to find a new strategy for 5G communication with 3D integration of multi-function chips.

The AIP module was composed of two stacked layers: the antenna layer and RF layer. After architecture design and performance simulation, the module was fabricated, The 8 × 8 antenna array was lithography patterned on the 12 inch glass wafer to reduce the parasitic parameters effect, and the signal feeding interface was fabricated on the backside of the glass substrate.

AIP module demonstrates a size of 180 mm × 180mm × 1mm, and its function covers the complete RF front-end chain from the antenna to signal to process and can be applied in 5 G communication and automotive components.

With three RF multi-function chips and two through silicon via (TSV) chips were embedded in the 12 inch compound wafer through the fan-out packaging process; two layers were interconnected with TSV and re-distributed layers.

The purpose of this paper is to describe the behavior of different lead-free solders (95.5Sn3.8Ag0.7Cu, i.e. SAC387 and Sn7In4.1Ag0.5Cu, i.e. SAC-In) in thermomechanically loaded non-collapsible ball grid array (BGA) joints of a low-temperature co-fired ceramic (LTCC) module. The validity of a modified Engelmaier’s model was tested to verify its capability to predict the characteristic lifetime of an LTCC module assembly implementable in field applications.

Five printed wiring board (PWB) assemblies, each carrying eight LTCC modules, were fabricated and exposed to a temperature cycling test over a −40 to 125°C temperature range to determine the characteristic lifetimes of interconnections in the LTCC module/PWB assemblies. The failure mechanisms of the test assemblies were verified using scanning acoustic microscopy, scanning electron microscopy (SEM) and field emission SEM investigation. A stress-dependent Engelmaier’s model, adjusted for plastic-core solder ball (PCSB) BGA structures, was used to predict the characteristic lifetimes of the assemblies.

Depending on the joint configuration, characteristic lifetimes of up to 1,920 cycles were achieved in the thermal cycling testing. The results showed that intergranular (creep) failures occurred primarily only in the joints containing Sn7In4.1Ag0.5Cu solder. Other primary failure mechanisms (mixed transgranular/intergranular, separation of the intermetallic compound/solder interface and cracking in the interface between the ceramic and metallization) were observed in the other joint configurations. The modified Engelmaier’s model was found to predict the lifetime of interconnections with good accuracy. The results confirmed the superiority of SAC-In solder over SAC in terms of reliability, and also proved that an air cavity structure of the module, which enhances its radio frequency (RF) performance, did not degrade the reliability of the second-level interconnections of the test assemblies.

This paper shows the superiority of SAC-In solder over SAC387 solder in terms of reliability and verifies the applicability of the modified Engelmaier’s model as an accurate lifetime prediction method for PCSB BGA structures for the presented LTCC packages for RF/microwave telecommunication applications.

In the capricious span of this current millennium, there is a deafening roar in the demand for modernization in the sector of robotics and technology to perform tasks in an intelligent manner. Thus to replenish such necessities, the innovations and inventions of researchers came forward as blessings on human civilization due to their sheer ingenuity and relentless and arduous efforts with each nanosecond passed from now onwards. With the same sublime goal, same resilient endeavor, same aggressive demeanor, the paper on obstacle avoiding robots comes forward. The paper aims to discuss these issues.

It exhibits how to control a differential drive robot wirelessly by analog thumb joystick module with added obstacle avoidance protection. The variations made by the user in the control of analog thumb joystick module are fed as input to the Atmega 16 microcontroller board which further transfers it wirelessly to the robot through the radio frequency (RF) transmitting module. The Arduino mega microcontroller equipped to the robot cross-checks the instructions gained through the RF receiving module and provides power accordingly to the geared motors through the motor driver board for movement along with scanning the environment to avoid obstacles present thereby.

The improvisation of RF technology in controlling the obstacle avoiding robot has enhanced its application and reliability by leaps and bounds reducing the anxiety and tension of the human controller.

With more advanced algorithm and genuine deployment sensors, the idea behind this research work can be used in humanoid robots which can help immensely in going to the extremely dangerous terrains, war zones and also in human rescue operations.

In this paper, Substrate Integrated Packaging (SIP) based on thin film multilayer technology is presented. Coplanar waveguide feedthroughs calculated with 3D‐Finite Differential Methods were manufactured using a ceramic or silicon carrier, gold conductors and polyimide as dielectric. The substrate integrated packages were realized with metallic frames and lids mounted on the thin film circuitry. S‐parameter measurements show the superior quality of the feedthroughs. To verify the new packaging concept, a 10GHz and a 58GHz amplifier module were realized. From these modules the potential of the SIP‐technology is demonstrated.

Engineers across many disciplines are becoming interested in wireless communication, however the plethora of standards, frequencies and technologies can lead to considerable confusion. This article presents some decision criteria to assist the reader selecting the most suitable technology. Further, it highlights other issues to prepare for integrating RF.

The purpose of this paper is to consider the adequacy of various microstrip filters’ behaviour based on different low-temperature co-fired ceramic (LTCC) dielectrics in the high frequency (HF) area up to 13 GHz.

Low pass, band pass and band stop filters for ultra-wideband radar systems were designed, simulated, fabricated and measured using three various dielectric substrates: Dupont GreenTape 951, Dupont GreenTape 9K7 and Murata LFC.

It is not possible to unambiguously determine the most suitable LTCC dielectric for these filter design because, in general, all designed filters fulfilled requirements (attenuation, cut off frequencies) with minimal divergences, but temperature-stable dielectric and physical properties of Murata LFC make them a promising ceramic for HF application (repeatability of realised experiments).

The novelty of this work lies in unconventional usage of LTCC as material with defined dielectric properties proper for HF applications.

In land grid array hybrid or system in package type products passive integration on silicon dies are flip chip mounted on a laminate substrate using Pb‐free solder. To increase the solder bump fatigue life, underfill is applied. The application of underfill resulted in the occurrence of an unexpected and unwanted phenomenon: solder flowing out of the underfill during a second level reflow test. The occurrence of solder flow‐out seemed associated with moisturizing as part of a moisture sensitivity level assessment. The solder flow‐out is preceded by delamination, initiated by mismatch in coefficient of thermal expansion between copper through‐holes and laminate. This paper aims to describe the phenomenon and possible solutions by combining experiments with finite element (FE) simulations.

Ways to prevent this kind of overstress failures are investigated by design of experiments and observed trends are compared with thermo‐mechanical FE simulations. A significant contribution is made by through‐holes close to the bump and underfill fillet.

The FE simulations confirmed increased thermo‐mechanical induced stress levels by bad positioning of vias, underfill and solder. The integrity of the flip chip construction is substantially improved by optimising product design, underfill material and the associated assembly process.

This paper is a useful source of information on the causes of delamination and solder flow‐out.

Conventionally, fleet maintenance decisions are made based on the level of repair (LOR) analysis. A general assumption made during LOR analysis is the consideration of the lifetime distribution with constant failure rate (CFR). However, industries do use preventive maintenance (PM) to extend the life of such components, which in turn may affect the LOR decisions such as repair/move/discard. The CFR assumption does not allow the consideration of effect of PM in LOR analysis. The purpose of this paper is to develop a more practical LOR analysis approach, considering the time-dependent failure rate (TDFR) of components and the effect of PM.

In the proposed methodology, first, a detailed life cycle model considering the effect of various parameters related to LOR and PM is developed. A simulation-based genetic algorithm approach is then used to obtain an integrated solution for LOR and PM schedule decisions. The model is also evaluated for the various cases of quality of maintenance measured in terms of degree of restoration.

The results, from the illustrative example for a multi-indenture and multi-echelon fleet maintenance network, show that the proposed integrated strategy leads to better LCC performance compare to the conventional approach. Additionally, it is identified that the degree of restoration also affects the PM schedule as well as LOR decisions of the fleet system. Therefore, consideration of TDFR is important to truly optimize the LOR decisions. The proposed approach can be applied to fleet of any equipment.

The approach is illustrated using a hypothetical example of an industrial system. A more complex system structure in terms of number of machines, types of machines (identical vs non-identical), number of echelons, possible repair actions at various echelons, etc. may be present for a particular industrial case. However, the approach presented is generic and can be extended to any system. Moreover, the aim of the paper is to highlight the importance of the considering PM and quality of maintenance in LOR decision making.

To the best of the authors’ knowledge, this is the first work which considers the effect of PM and quality of maintenance on LOR analysis. Consideration of TDFR and imperfect maintenance while optimizing LOR decisions is a complex problem. Thus, the work is of high significance from the research point of view. Also, most of the real life fleet systems use PM to extend the life of the equipment. Thus, present paper is a more practical approach for LOR analysis of such systems.