Rx Modules Research Articles

A Spatially Diverse 2TX-3RX Galvanic-Coupled Transdural Telemetry for Tether-Less Distributed Brain-Computer Interfaces.

A near-field galvanic coupled transdural telemetry ASICs for intracortical brain-computer interfaces is presented. The proposed design features a two channels transmitter and three channels receiver (2TX-3RX) topology, which introduces spatial diversity to effectively mitigate misalignments (both lateral and rotational) between the brain and the skull and recovers the path loss by 13 dB when the RX is in the worst-case blind spot. This spatial diversity also allows the presented telemetry to support the spatial division multiplexing required for a high-capacity multi-implant distributed network. It achieves a signal-to-interference ratio of 12 dB, even with the adjacent interference node placed only 8mm away from the desired link. While consuming only 0.33 mW for each channel, the presented RX achieves a wide bandwidth of 360 MHz and a low input referred noise of 13.21 nV/√Hz. The presented telemetry achieves a 270 Mbps data rate with a BER < 10-6 and an energy efficiency of 3.4 pJ/b and 3.7 pJ/b, respectively. The core footprint of the TX and RX modules is only 100 and 52 mm2, respectively, minimizing the invasiveness of the surgery. The proposed transdural telemetry system has been characterized ex-vivo with a 7-mm thick porcine tissue.

Electromagnetic Detection System with Magnetic Dipole Source for Near-Surface Detection.

This paper proposes a nondestructive, separate transmitter-receiver (TX-RX) electromagnetic measurement system for near-surface detection. Different from the traditional dual-coil integrated design, the proposed transient electromagnetic (TEM) system performs shallow subsurface detection using independent TX coil and movable RX coils. This configuration requires a large primary field so that the far-away secondary field is able to generate reliably induced voltages. To achieve this goal, a bipolar current-pulsed power supply (BCPPS) with a late resonant charging strategy is designed to produce a sufficiently large magnetic moment for the exciting coil with low source interference. The magnetic dipole source (MDS) with a large proportion of weight is separated from the field observation device and does not need to be dragged or transported during the detection process. This setup lowers the weight of the scanning device to 3 kg and greatly improves the measurement efficiency. The results of the laboratory test verify the effectiveness of the separate MDS and RX module system. Field experimental detection further demonstrates that the proposed system can realize highly efficient and shallow surface detection within a 200 m range of the MDS device.

A 76-Gbit/s 265-GHz CMOS Receiver With WR-3.4 Waveguide Interface

A 76-Gbit/s 265-GHz CMOS receiver (RX) modularized with a WR-3.4 waveguide interface is presented. It is a mixer-first RX fabricated using a 40-nm CMOS technology. The primary design focus is simplicity and the resulting low noise and loss and high conversion gain (CG). To allow for both on-wafer and packaged measurements, ON-chip transmission lines are designed such that their characteristics are relatively insensitive to the presence or absence of adhesive covering the chip. The RX chip is flip-chip-mounted on a multilayer printed circuit board (PCB). Built into the PCB is a waveguide transition using double-resonant stacked patches for wideband operation. The CMOS RX module achieves the highest wireless data rate of 76 Gbit/s with 16 QAM, which is comparable to 80 Gbit/s reported previously for a CMOS RX with on-wafer probing measurement.

Rancang Bangun Driver PZT dan Filtering Data Akustik Pada Sonar Aktif

Acoustic transducer is a source level component in the sonar equation that is indispensable as an underwater acoustic energy source, with a certain emission pattern called beamforming. In this research, we designed the construction of a driver circuit to trigger a piezoelectric (PZT) transducer to produce an acoustic energy beam for the purpose of detecting underwater targets. The manufacture of an acoustic driver with a simple working principle has been carried out to provide transmit (TX) and receive (RX) commands. The RX module will receive the acoustic signal from the TX and the results are recorded for analysis. The mixing of the information signal with noise makes the information obtained cannot be directly verified so that a signal processing process is needed to be able to separate the information signal and noise. Calibration using a spherical target was carried out to determine the detection results and the acoustic intensity level. Signal analysis and visualization methods use Fast Fourier Transform (FFT) and wavelets.

Balancing of Common DC-Bus Parallel-Connected Modular Inductive Power Transfer Systems

The aim of this article is to design a modular, fault-tolerant multi-transmitter (Tx)/multi-receiver (Rx) parallel-connected common dc-bus inductive power transfer (IPT) system to replace slip rings in wind turbines or brushless exciters. In parallel-connected common dc-bus systems, current unbalance is a major issue that results in thermal stresses and over current or voltages. In this article, two different new current balancing methods are proposed: cross-coupled Rx modules and intentional detuning of Rx-side resonant frequency. These methods are investigated both analytically and experimentally for a single Tx and two Rx system for a 500-W prototype. The proposed methods are tested independently, and then, the combined current balancing method is also investigated. For the same misalignment case, cross coupled/detuned has a 55.8&#x0025; current balancing improvement compared with decoupled/fully tuned topology.

A Multiband/Multistandard 15–57 GHz Receive Phased-Array Module Based on 4 × 1 Beamformer IC and Supporting 5G NR FR2 Operation

This work presents a 15&#x2013;57 GHz multiband/ multistandard phased-array architecture for the fifth-generation (5G) new radio (NR) frequency range 2 (FR2) bands. An eight-element phased-array receive module is demonstrated based on two four-channel wideband beamformer chips designed in the SiGe BiCMOS process and flipped on a low-cost printed circuit board. The SiGe Rx chip employs RF beamforming and is designed to interface to a wideband differential Vivaldi antenna array. Each channel consists of a low-noise amplifier (LNA), active phase shifter with 5-bit resolution, variable gain amplifier (VGA), and differential-to-single-ended stage. The four channels are combined using a wideband two-stage on-chip Wilkinson network. The beamformer has a peak electronic gain of 24&#x2013;25 dB and a 4.7&#x2013;6.2 dB noise figure (NF) with a &#x2212;29 to &#x2212;24 dBm input <inline-formula> <tex-math notation="LaTeX">$P_{\boldsymbol {1\,dB}}$ </tex-math></inline-formula> at 20&#x2013;40 GHz. The eight-element phased-array module also achieved ultra-wideband frequency response with flat gain and low-system NF. The phased array scans &#x00B1;55&#x00B0; with <inline-formula> <tex-math notation="LaTeX">$ &lt; -12$ </tex-math></inline-formula>-dB sidelobes demonstrating multiband operation. A 1.2-m over-the-air (OTA) link measurement using the eight-element Rx module supports 400-MHz 256-QAM OFDMA modulation with &#x003C; 2.76&#x0025; error vector magnitude (EVM) at multiple 5G NR FR2 bands. To the author&#x2019;s knowledge, this work achieves the widest bandwidth phased array enabling the construction of multistandard systems.

A Novel Strategy for Monitoring a PV Junction Box Based on LoRa in a 3 kW Residential PV System

Recently, 3 kW residential PV (Photovoltaic) junction boxes have mainly been installed on the roof or outer wall of building. Wired and wireless monitoring systems are being implemented by RS-485 and WIFI/IoT. However, conventional monitoring systems have a communication limitation according to the distance and environment. It cannot receive any information when a failure of the PV junction box occurs. Therefore, there is a need for a strategy to determine whether the fuse and diode in the PV junction box are faulty through voltage and current sensors. In this paper, we propose a novel strategy for monitoring PV junction boxes, based on LoRa (Long Range). The TTGO LoRa32 V2.0 module with LoRa and various input and output ports is utilized. The wireless TX module transmits various data collected from the PV junction box to the RX module in real time. In addition, the RX module displays the received data on an LCD (Liquid Crystal Display) screen so that the user can intuitively identify it, and the data is recorded on the internal storage device or database in the web server. The manufactured PV junction box monitoring system was tested under a 3 kW PV system. Additionally, communication reception has stable signal intensity overall, both indoors and outdoors. In particular, it shows excellent characteristics in maintaining RSSI (Received Signal Strength Indicator) &gt; −99 dBm and PER (Packet Error Rate) &lt; 2.7%, up to a radius of 200 m, even in NLOS (Non Line-Of-Sight) environments. Although some packet loss occurred, it was confirmed that invisible communication was possible up to 300 m.

PHY-DTR: An Efficient PHY based Digital Transceiver for Body Coupled Communication using IEEE 802.3 on FPGA Platform

Body coupled communication (BCC) is an efficient networking approach to body area network (BAN) based on Human-centric communication. The BCC provides interference only between humans in very close proximity. In this work, an efficient Physical layer (PHY) based digital transceiver) is designed for BCC. The digital transceiver Module mainly contains a Digital transmitter (TX) with Manchester encoder, clock synchronization unit, and Digital receiver (RX) with Manchester decoder. The TX and RX modules are designed using a finite state machine as per the IEEE 802.3 Standards. The complete work is also varied for BAN applications by connecting two Application layer transceivers and two Physical layer-based digital transceivers. The architecture is simulated in a Model-sim simulator. The complete Module is synthesized using different FPGA families, and the hardware design constraints are contrasted. The digital transceiver works at 231.28 MHz operating frequency, consumes 0.113W power, and provides a 7.7 Mbps data rate and 4.67 Kbps/Slice efficiency on Artix-7 FPGA. The proposed transceiver is also compared with existing digital transceivers with hardware constraints improvements.

Optical Power Distributions for 4×4 MIMO Visible Light Communications in Indoor Environment

Visible Light Communication (VLC) has emerged as a powerful technique for wireless communication systems. Providing high data rate and increasing capacity are the major problems in VLC. Recent evidence suggests that Multiple Input Multiple Output (MIMO) technique can offers improved data rates and increased link range. This paper describes the design and implementation of visible light communication system in indoor environment exploring the benefits of MIMO. The specific objective of this research was to implement a 4×4 Multiple Input (LEDs) Multiple Output (photodetectors)-VLC communication system, where a 16 white power LEDs in four arrays are setting up at transmitter and four RX modules are setting up at receiver side without the need for additional power or bandwidth as well as analyze a mathematical model for a VLC- 4×4 MIMO with different modes such as the suitable angles to cover the entire room. The research designs practically an electronic circuit for the transmitter and receiver with inexpensive components. The power distribution of different propagation modes is calculated for Single Input Single Output (SISO) and MIMO channels in typical room dimensions. The results in this paper indicate that the power is distributed uniformly for entire room when implemented VLC-MIMO as compared to VLC-SISO. Furthermore, a 4×4 MIMO implementing VLC is compared in term of BER vs. SINR with SISO communication system for both Line of Sight (LOS) and Non Line of Sight (NLOS) propagation modes. Comparing the two results of LOS and NLOS, it can be seen that a 4×4 MIMO implementing VLC for LOS perform better than the same system with NLOS due to decreasing in the received power resulted from the multipath effect.

38-GHz Phased Array Transmitter and Receiver Based on Scalable Phased Array Modules With Endfire Antenna Arrays for 5G MMW Data Links

This article presents the 38-GHz phased array 32-element Tx and 16-element Rx with 2-GHz IF and 5-GHz LO for fifth-generation (5G) millimeter-wave (MMW) communications. The Tx and Rx beamformers and upconverters/downconverters are fabricated in 65-nm CMOS. The PAs and LNAs near antenna ends are fabricated in 0.15- $\mu \text{m}$ GaAs pHEMT. The eight-element Tx and four-element Rx phased array printed circuit board (PCB) modules integrated with multiple integrated circuits (ICs) and endfire antennas are implemented as unit cells. Four pieces of Tx modules are vertically stacked to construct an $8\times {4}$ brick array (planar array), while four Rx modules are to construct a $4\times {4}$ array. According to 38-GHz over-the-air (OTA) measurements, the 32-element Tx shows 47.5-dBm equivalent isotropic radiated power (EIRP) at OP $_{\mathrm {1 ~dB}}$ with −35.2-dB image rejection ratio (IMRR) and −37.4-dB $\times 8$ LORR. The 16-element Rx at 38 GHz shows −4-dBm OP $_{\mathrm {1~dB}}$ with −28-dB IMRR and −36.6-dB LORR. The Tx and Rx support the beam scanning around ±60° azimuth and ±30° elevation planes. The Tx-to-Rx wireless data link demonstrates 64 quadrature amplitude modulation (QAM)/400 M-BR, 256 QAM/200 M-BR, and 512 QAM/100 M-BR in 20 m. To the best of our knowledge, this work is the first 5G 37-/39-GHz phased array Tx/Rx using the scalable brick array configuration and demonstrating competitive performances compared with previous works.

A QPSK 110-Gb/s Polarization-Diversity MIMO Wireless Link With a 220–255 GHz Tunable LO in a SiGe HBT Technology

In this article, a polarization-diversity technique multiple-input multiple-output (MIMO) is demonstrated to double the spectral efficiency of a line-of-sight quadrature phase-shift keying (QPSK) wireless link at 220-255 GHz with a pair of highly integrated single-chip transmitter (TX) and receiver (RX) front-end modules in 0.13-μm SiGe HBT technology ( f T/ f max = 350/550 GHz) exploiting only a low-cost wire-bonded chip-on-board packaging solution for high-speed baseband (BB) signals. Both TX and RX chips accommodate two independent fundamentally operated direct-conversion in-phase and quadrature (IQ) paths with separately tunable on-chip multiplier-based (×16) local oscillator (LO) generation paths driven from a single external highly stable 13.75-16-GHz frequency synthesizer. On the RX side, a mixer-first architecture is implemented to improve the symmetry between upper and lower sidebands (USB and LSB) at the cost of an increased noise figure (NF), whereas, on the TX chip, each upconversion mixer is followed by a gain-bandwidth (BW)-limited fourstage power amplifier (PA) to support the link budget at a meter distance. Next, two independent IQ data streams from the upconversion/downconversion paths on each chip are directed to a common lens-coupled broadband on-chip slot antenna system. This way, two orthogonal circular polarizations [left-handed circular polarization (LHCP) and right-handed circular polarization (RHCP)] can be transmitted with sufficient isolation for link operation without the need for a high-speed depolarizer in the BB for any relative orientation between TX and RX modules. The antenna combined with a 9-mm diameter Si-lens provides a directivity of 23.5-27 dBi at 210-270 GHz for each of the modules. This, along with a peak radiated power of 7.5 dBm/ch from the TX module, and the cascaded conversion gain (CG)/single sideband (SSB) NF of 18/18 dB/ch for the RX module followed by a broadband amplifier (PSPL5882) from Tektronix allowed successful transmission of two independent QPSK data streams with an aggregate speed of 110 and 80 Gb/s over 1 and 2 m, respectively, at 230 GHz with a board-level limited channel BB bandwidth (BW) of 13.5 GHz.

Nongalvanic Generic Packaging Solution Demonstrated in a Fully Integrated D-Band Receiver

This article presents a packaging technique for monolithic microwave integrated circuits (MMIC) demonstrated in a fully integrated receiver (Rx) module at the D -band (110–170 GHz). The solution consists of an MMIC-to-waveguide transition realized using an on-chip probe mounted in the E -plane of a split-block waveguide module. An artificial magnetic conductor structure is implemented to suppress cavity modes and achieve better coupling from the waveguide to the probe. The transition's performance is experimentally verified using a back-to-back test chip, and measurement results show that the proposed packaging solution achieves a low insertion loss of only 0.7 dB and covers a very wide frequency range extending from 105 to 175 GHz. The proposed transition is also integrated with an in-phase/quadrature-phase (I/Q) Rx on the same chip. The Rx is realized in a 250-nm indium phosphide double heterojunction bipolar transistor technology and consists of a low-noise amplifier, an I/Q mixer, and a frequency tripler. Measurement results show that the Rx module achieves an average conversion gain of 23 dB across the frequency range of 110–145 GHz and has an average noise figure of 10.6 dB. The Rx MMIC has a dc power consumption of 440 mW and occupies an area of 1.6 × 1.6 mm2. This article addresses one of the main challenges in systems operating above 100 GHz and presents a fully integrated packaging solution that suits large integrated circuits and does not require any galvanic contacts nor impose any limitations on MMIC dimensions.

Four-Port Dual-Mode Diplexer with High Signal Isolation

An ease of four-port dual-mode diplexer with high signal isolation is presented. A compact dual-mode diplexer with high signal isolation between the Rx and Tx modules is achievable by only using one resonator filter topology. Two back-to-back dual-mode diplexers have a 180° phase shift in one branch. The high isolation can be achieved by amplitude and phase cancellation technique. The delayed transmission line can be easily achieved by the phase shifter. The simulated and measured four-port dual-mode diplexers are designed at the centre frequency of Rx/Tx at 1.95 GHz and 2.14 GHz, respectively. The measured results of Rx/Tx dual-mode diplexer devices are presented with 47.1 dB Rx/Tx isolation. This four-port dual-mode diplexer achieves the isolation (S32) of more than 24.1 dB when compared with the conventional three-port dual-mode diplexer structure.

Autotuning Control System by Variation of Self-Inductance for Dynamic Wireless EV Charging With Small Air Gap

In this paper, an autotuning control system (ACS), which utilizes the variation of self-inductance of a transmitter (Tx) coil caused by a ferrite core of a receiver (Rx), is newly proposed for the dynamic wireless electric vehicle (EV) charging. A Tx module consists of only passive elements that include a Tx coil, a partially compensated capacitor in series with the Tx coil, and a parallel compensation capacitor. All Tx modules share an ac bus line that passes the output filter of an inverter in parallel without any active switches. The current of the coupled Tx coil increases automatically without any manipulations such as controlling the power switches, sensing, or communication when the Rx module is approaching. Not only the system efficiency is increased by the reduction of the conduction losses from the uncoupled Tx modules, but control also becomes simpler because sensors are not required for detecting EVs, and the constant output voltage characteristics can be obtained. Through experiments, it was found that the proposed ACS is suitable for applications such as a tram that runs along an orbit with a small air gap, such as a train. The results showed that the current of a coupled Tx coil increased 11.6 times larger than that of an uncoupled Tx coil, at which time the dc–dc efficiency achieved was 88.4% for an output power of 766 W (10 Ω of load resistance) at the laboratory scale.

Flexible wireless power transfer module implemented with aerojet-printing and laser-sintering of rigid NiZn–ferrite ceramic films

Integrating high-performance inorganic ceramic materials into flexible electronics has long been considered a technical challenge because of the conceptual clash between rigidity and flexibility. Moreover, the inevitable high-temperature processing of ceramic materials is incompatible with other materials used in flexible electronics. To address these issues, this work suggests a novel solution to incorporate rigid NiZn–ferrite (NZF) ceramic films into a flexible wireless power transfer (WPT) module via aerojet-printing and laser-sintering processes. The aerojet-printed NZF films exhibited excellent magnetic properties after laser sintering. Although laser sintering induced unexpected microcracks in the NZF films due to the rapid heating of the laser and the high porosity of the printed films, they played an important role in imparting flexibility to the NZF films. The laser-sintered NZF (LSNZF) films were separated from the substrate using an Ag sacrificial layer and then embedded into polydimethylsiloxane (PDMS). The flexibility of the PDMS-embedded LSNZF films was investigated via a bending test. The flexible WPT receiving (Rx) module was completed by combining the PDMS-embedded LSNZF films with an inkjet-printed Ag inductor coil. The performance of the flexible WPT Rx module was verified via wireless activation of light emitting diodes.

High spatial resolution identification of hematoma in inhomogeneous head phantom using broadband fNIR system

This paper presents a novel method for early detection of hematomas using highly sensitive optical fNIR imaging methods based on broadband photon migration. The NIR experimental measurements of inhomogeneous multi-layer phantoms representing human head are compared to 3D numerical modeling over broadband frequencies of 30–1000 MHz. A finite element method (FEM) simulation of the head phantom are compared to measurements of insertion loss and phase using custom-designed broadband free space optical transmitter (Tx) and receiver (Rx) modules that are developed for photon migration at wavelengths of 670 nm, 795 nm, 850 nm, though results of 670 nm are discussed here. Standard error is used to compute error between 3D FEM modeling and experimental measurements by fitting experimental data to the asqrt {frequency} + b . Error results are shown at narrowband and broadband frequency modulation in order to have confidence in 3D numerical modeling. A novel method is established here to identify presence of hematoma based on first and second derivatives of changes in insertion loss and phase (∆IL and ∆IP), where frequency modulated photons sensitive to different sizes of hematoma is identified for wavelength of 670 nm. The high accuracy of this comparison provides confidence in optical bio-imaging and its eventual application to TBI detection.

A Linear-Mode LiDAR Sensor Using a Multi-Channel CMOS Transimpedance Amplifier Array

This paper presents a linear-mode optical sensor for the feasible applications of unmanned vehicle LiDAR systems, in which a pulsed-erbium fiber laser is exploited as a light source and a 16-channel transimpedance amplifier (TIA) array is utilized in an optical Rx module with low-cost InGaAs PIN photodiodes. In particular, a voltage-mode CMOS feedforward (VCF-TIA) is newly proposed to achieve twice higher transimpedance gain with lower noise and similar bandwidth characteristics than a conventional inverter TIA, thereby enabling longer detection. Test chips of the 16-channel VCF-TIA array realized in a standard 0.18- $\mu \text{m}$ CMOS process demonstrate 76.3-dB $\Omega $ transimpedance gain, 6.3-pA/sqrt(Hz) average noise current spectral density, less than −33-dB crosstalk between channels, and 29.8-mW power dissipation per channel from a single 1.8-V supply. Automatic gain control is also equipped to extend input dynamic range for near-range detection. Hence, the proposed linear-mode optical sensor clearly detects the reflected optical pulses from the target of 5% reflection rate within the range of 0.5–25 m.

Design Consideration on Converged Rx SAW Duplexer Module for Multiband RF Front End

This paper presents the design consideration on a converged Rx surface acoustic wave (SAW) duplexer module for integrated RF front end. Two different matching-circuit and notch-circuit configurations were examined with importance placed on electrical characteristics (insertion loss and isolation of duplexer) and simplification of module, respectively. From circuit simulations and examinations, we verified that a simplified design was best in terms of both characteristics and space in the case of a finite inductor’s Q. We also fabricate a quad-band converged Rx module (Band I + II, V + VIII) using an SAW duplexer and verified that its electrical characteristics agree well with our simulation results.

Gas Spectroscopy System for Breath Analysis at mm-wave/THz Using SiGe BiCMOS Circuits

The unique fingerprint spectra of volatile organic compounds for breath analysis and toxic industrial chemicals make an mm-wave (mmW)/THz gas sensor very specific and sensitive. This paper reviews and updates results of our recent work on sensor systems for gas spectroscopy based on integrated transmitter (TX) and receiver (RX), which are developed and fabricated in IHP’s $0.13~\mu \text{m}$ SiGe BiCMOS technology. In this paper, we present an mmW/THz spectroscopic system including a folded gas absorption cell of 1.9 m length between the TX and RX modules. We discuss the results and specifications of our sensor system based on integrated TX and RX. We demonstrate TXs and RXs with integrated antennas for spectroscopy at 238–252 GHz and 494–500 GHz using integer- $N$ phase-locked loops (PLLs). We present a compact system by using fractional- ${N}$ PLLs allowing frequency ramps for the TX and RX, and for TX with superimposed frequency shift keying or reference frequency modulation. In another configuration, the voltage controlled oscillators of the TX and RX local oscillator are tuned directly without PLLs by applying external voltages. Further developments of our system are aimed at realizing an even wider frequency span by switching between frequency bands, and to use a more compact gas absorption cell.

100 Gbps (4 × 25 Gbps) Optical Receiver Module Packaged in Chip-on-Board Based on Germanium Photodetector

100 Gbps (4 × 25 Gbps) optical receiver (Rx) module is demonstrated using Germanium (Ge) photodetector (PD) which is fabricated through Silicon-photonics process using 750 ohm-cm of high-resistivity silicon oxide insulator (SOI) wafer. Trans-impedance amplifier (TIA) and Ge PD are packaged with chip-on-board (COB) manner on a printed circuit board (PCB). High speed PCB for the assembly of both electronic and photonic devices in COB package is precisely designed from the material selection to the device footprint layout and transmission line design. The layout on PCB is optimized using high frequency simulation tool of HFSS to minimize RF loss happening in the transmission line and electrical interconnection points of bond wires. Electrical-optical (EO) S-parameter measurement for the Ge PD shows 22 GHz of transmittance (S21) 3dB bandwidth. Photocurrents of the photodetector induced by the optical input power are analyzed for signal integrity both TIA ON and OFF states. Photocurrent changes by the misalignment of the lensed optical fiber coupled to the edge coupler of the Ge PD shows that 3dB misalignment tolerances are 5.5 µm in the longitudinal and around +/-1 µm in the lateral directions. This COB packaging technique of optical Rx module can be applied for the integration and assembly of the optical module of higher data rate of 100 Gbps and beyond.