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A growing interest in AI and deep learning applications necessitates the development of efficient power delivery networks (PDNs) to manage broadband impedance in high-speed switching environments. This paper evaluates the electromagnetic performance of horizontal, vertical, and embedded PDNs in fanout packages, with particular emphasis on vertical and embedded configurations, both less explored for noise mitigation. Simulations indicate that embedded PDNs significantly reduce commonmode (CM) and differential-mode (DM) radiation, achieving levels between 20-78 dBµV. Additionally, measurements show that embedded PDNs maintain a lower electric field strength of 1.9 V/m for DM radiation as compared to 2.7 V/m for horizontal PDNs and 11.4 V/m for vertical PDNs. Advanced shielding with 5-µm thick Cu-CoNiFe layers further reduces magnetic field emissions by 30-45 dB. These findings demonstrate that embedded PDNs are a more effective solution for electromagnetic interference (EMI) mitigation in future electronic systems, offering superior noise control and reduced crosstalk. 

A 4-channel code-multiplexed digital receiver is presented for multiple-input-multiple-output (MIMO) applications targeting 5G millimeter-wave (mm-Wave) communications. The receiver employs a code-multiplexing (CM) topology where multiple channels are encoded with unique orthogonal Walsh­ Hadamard codes and multiplexed into a single-channel for digitization. This approach overcomes the bottleneck of hardware complexity, cost, and power consumption in traditional multiplexing topologies by employing a single wideband analog-to-digital converter (ADC) to serve several channels. The article presents an end-to-end testbed to demonstrate the effectiveness of the proposed Code-Multiplexed Digital Receiver (CMDR) that consists of l ) ultrawideband (UWB) tightly-coupled dipole array (TCDA), 2) a custom-designed encoder circuit board (ECB), and 3) a Radio-Frequency System-on-Chip (RFSoC) field­ programmable gate array (FPGA) for encoding and decoding. The code sequences were generated at a maximum clock frequency of 400 MHz. Extensive experimental measurements were performed and test results were validated using performance metrics such as normalized mean square error (NMSE) and adjacent channel interference (ACI). Test results showed ACI of >20 dB, NMSE = -24.592 dB and little or no degradation in signal-to-noise ratio (SNR). To the best of our knowledge, this is the highest clock frequency and ACI value for hardware validation of channel multiplexing scheme reported in the literature. 

Electromagnetic shielding often requires the integration of thick shielding structures in the form of metal casings, walls, or via arrays. These shields typically isolate the entire package from external or internal noise sources. In some cases, they also isolate components within the package. However, integration of shielding structures with the required performance creates miniaturization and fabrication constraints, and results in longer product development cycle times. To address these limitations, a novel approach is presented for component- and package-level shielding. This approach is based on electromagnetic interference (EMI) shield integration through a microassembly of prefabricated shields inside microslots in packages and printed circuit boards (PCBs). This approach eliminates many of the design and process constraints during the shield integration within packages. Various design options were considered to mitigate capacitive and inductive coupling between representative microstrip lines that act as aggressors and victims. Three types of EMI shielding architectures, U-shaped, inverted-L-shaped, and T-shaped, were investigated with 17.5 μm copper. The fabricated EMI shields were studied for their shield performance, both as a compartmental shield between specific components and as a conformal shield from external and internal noises. The role of the ground termination was also investigated to further optimize the shielding performance. 

Reconfigurable Intelligent Surfaces (RIS) also known as Intelligent Reflecting Surfaces (IRS) often depend upon metasurfaces. These typically comprise of a large array of passive elements that can be fabricated to modulate reflection amplitude or phase or both to create tunable functions that are independently controlled. Various RIS are developed to improve spectral efficiency through ultrawideband antennas, enhanced beamforming with higher gain and bandwidth, spatial reconfigurability, selective and adjustable isolation, and other desired features. Several approaches to tune the RIS performance are being explored. This paper reviews the primary approaches and the benefit of emerging tunable nanomaterials in achieving such RIS functions. Designs with 1-bit and 6-bit phase shifters are discussed in the first part. Various opportunities with nanomaterials and nanodevices to induce such phase shifts are discussed in the last part of the paper. 

Wireless power transmission is becoming a key technology in realizing future sensor nodes. Current approaches are based on inductive links or RF telemetry, both face limitations in achieving higher power densities. Multiferroic telemetry can address this challenge and provide a new approach for remote powering. This paper describes an integrated piezoelectric film on magnetostrictive carriers to achieve highly-efficient multiferroic functions. Various multi-layered architectures were investigated for output power performance. The multiferroic flexible stacks subsequently integrated with diode rectifier topologies and storage capacitors to generate the desired output. Results demonstrate new power telemetry opportunities with advanced material stacks with flex package integration.