Switch Matrix Research Articles

A novel approach for characterization of multibeam communication payloads

SummaryCommunication payload architecture has changed from a conventional single broad beam to a large number of spot beam forms to meet the ever‐increasing data rate demand. Owing to the large telecommunication requirements of the user, current generation satellites are equipped with a large number of transponders/beams. Due to the increased number of payload beams, performance evaluation and validation time increases during all stages of the satellite integration process. Also, satellite testing in thermal–vacuum (TVAC) conditions is hugely cost‐intensive. Under such circumstances, the conventional test setup established for multibeam payload characterization presents limitations and increases overall measurement time. The paper proposes a novel switch matrix (SWM) based architecture for integrated multibeam payload characterization at payload input and output to significantly reduce effective uplink and downlink transmission line chains required for RF characterization without compromising overall measurement accuracy. We have developed a Telecommand and Telemetry (TCTM) simulator system for closed‐loop automated switching of switches in SWM to reduce human intervention and ensure safety aspects of payload. We present the SWM approach for two classes of high throughput satellites (HTS), namely, symmetrical and asymmetrical architectures. The results show that the proposed approach is robust and advantageous in overall RF performance, reduction in the number of interfaces, electromagnetic interference and electromagnetic susceptibility (EMI/EMC) considerations, electrical integrity, and ground test setup complexity compared with conventional characterization philosophy.

A Multifunctional Video Switching Matrix Design

The use of Video Switching Matrix can greatly improve the utilization rate of internal space such as ships and submarines. This paper designs a multifunctional video switching matrix, which can realize 16-channel HDMI and VGA video signal input and 8-channel HDMI and VGA video signal output function. It can meet the complex scenes of HDMI and VGA integrated video input and output. This design realizes the conversion of input and output video formats through the front-end HDMI to VGA unit and the back-end VGA to HDMI unit. The middle RGB switching matrix is used to realize 16 input and 8 output selection of VGA video signal. It realizes the fusion of multi-channel dual-standard video switching. The module has the prospect of being applied to high reliability requirements in aerospace, navigation, and military industries.

Isolated High-Frequency Link PFC Rectifier With High Step-Down Factor and Reduced Energy Circulation

This article presents an isolated single-stage ac–dc high-frequency link full-bridge cycloconverter (HFLC) with high conversion ratio. Despite certain advantages, such topologies generally suffer from transformer leakage inductance problems and lack of effective modulation methods, particularly in the ac–dc operation mode. In this study, for the input current regulation with the power factor correction of the HFLC, a novel phase-shift modulation method is used. It allows soft-switched turn- <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">off</small> of the dc-side transistors and zero current switching of the ac-side matrix switches without additional circuits or topology modifications. The introduced time-varying regulation of the peak current can be easily implemented; as a result, merely minor energy circulation occurs. Moreover, two of the ac-side transistors operate with fundamental frequency. Design constraints of the concept are analyzed and discussed. For verification, a 1.2-kW 230 V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">AC</sub> to 48 V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">DC</sub> experimental prototype is used.

Chalcogenide Phase-Change Material Germanium Telluride for Radio-Frequency Applications: An overview

Chalcogenide phase-change materials (PCMs) have been widely used in optical storage media and nonvolatile memory devices applications. Over the past several years, there has been interest in exploiting PCM technology, especially germanium telluride (GeTe) and its alloys, for radio-frequency (RF) applications. The principle of operation of PCM-based RF devices is based on the ability of the material to transform from a high-resistivity (amorphous phase) to low-resistivity state (crystalline phase) and vice versa, with the application of a short, thermal pulse. Actuation pulses are applied to microheaters embedded with the PCM junction to switch between the two states. The PCM switch can exhibit more than five orders of resistance change between the two states. PCM-based RF switches are expected to bridge the gap between semiconductor switches and microelectromechanical systems (MEMS) switches as they combine the low insertion loss performance of MEMS technology and the small size and reliability performance of semiconductor technology. In addition to miniaturization, GeTe-based switches offer unique latching functionality and ease of monolithic integration with other RF circuits. This article presents an overview of PCM technology and its applications to RF circuits. A brief history of the technology is presented first, followed by a discussion of the basic characteristics of PCMs. The steps of a fabrication process of PCM RF devices are illustrated. A description of RF-PCM switch is presented in detail along with a comparison between RF performance of PCM switches and other existing commercial switches. As examples of application of the PCM technology to other RF circuits, the article concludes by presenting a crossbar switch matrix, phase shifter, and variable attenuator, realized using the PCM technology.

Model-Based Predictive Control with Graph Theory Approach Applied to Multilevel Back-to-Back Cascaded H-Bridge Converters

The multilevel back-to-back cascaded H-bridge converter (CHB-B2B) presents a significantly reduced components per level in comparison to other classical back-to-back multilevel topologies. However, this advantage cannot be fulfilled because of the several internal short circuits presented in the CHB-B2B when a conventional PWM modulation is applied. To solve this issue, a powerful math tool known as graph theory emerges as a solution for defining the converter switching matrix to be used with an appropriate control strategy, such as the model-based predictive control (MPC). Therefore, this research paper proposes a MPC with the graph theory approach applied to CHB-B2B which capable of not only eliminating the short circuit stages, but also exploring all the switching states remaining without losing the converter controllability and power quality. To demonstrate the proposed strategy applicability, the MPC with graph theory approach is tested in four different types of SST configurations, input-parallel output-parallel (IPOP), input-parallel output series (IPOS), input-series output-parallel (ISOP), and input-series output series (ISOS), attending distribution grids with different voltage and power levels. Real-time experimental results obtained in a hardware-in-the-loop (HIL) platform demonstrate the proposed strategy’s effectiveness, such as DC-link voltages regulation, multilevel voltage synthesis, and currents with reduced harmonic content.

Bypass diode and photovoltaic module failure analysis of 1.5kW solar PV array

ABSTRACT Solar photovoltaic (PV) is the widely preferred power generation source to meet the growing energy demands. Solar PV system must be made highly reliable and effectively utilized during the availability of the source. System reliability is the predominant factor to be considered because of the possibilities of various faults and various operating conditions to which PV system is subjected. The present work addresses three major faults that commonly occur in solar PV system, namely, failure of bypass diode, failure of PV module, and power generation mismatch due to panel replacement. This proposed work deals with the detection and clearance of these three faults. The failure of PV module results in a higher power reduction of 82% in the PV array. The switching matrix circuit is proposed to enhance the power obtained from PV system under the module failure fault. The faults are manually created in a typical 1.5 kW grid-connected PV system and rectified to enhance the power production in the PV array. An average power enhancement of 14% is obtained after the clearance of the power mismatch due to panel replacement. With the help of double bypass diode technique, output power is enhanced to 55.2% higher compared to before fault clearance at the same irradiance level. The experimental results obtained in 1.5 kW grid-connected solar PV system are studied and validated.

A dynamic reconfiguration method based on neuro-fuzzy control algorithm for partially shaded PV arrays

The partial shading on PV arrays causes power decrease, hot spots, and damage to its components. In addition, the performance of the PV array is reduced for the internal mismatch. This work proposes a novel dynamic, on line, low costs, and automatic method to mitigate these effects. The method considers the mismatch due to partial shading and cell variability. In this method, the entire PV array is fully dynamic, and auxiliary PV modules are not required. The PV modules are electrically rearranged while the same interconnection scheme is maintained. The method is based on the temperature, the global voltage, and the global current of the entire PV array. These global measurements reduce the number of sensors, signal processing, computing time, electrical connections, and implementation cost. The electrical rearrangement of the PV modules is controlled by a neuro-fuzzy algorithm, a connection control, and a switch matrix. The proposed approach was implemented in hardware and validated experimentally in a real PV array. The results show that the method has 97% effectiveness in distinguishing the cause of power decrease, a 100% effectiveness in locating the shaded PV module, and a 10% increase in the PV array output power.

Optical Switch Based on Ge2Sb2Se4Te1-Assisted Racetrack Microring

In this work, we have proposed and designed a 1 × 1 optical switch based on the optical phase-change material, Ge2Sb2Se4Te1 (GSST), for GSST-assisted silicon racetrack microring. Its optical power can periodically be exchanged between the straight silicon waveguide and the GSST/Si hybrid racetrack waveguide due to the formed directional coupling structure. By changing GSST from the crystalline state to the amorphous state, the switch shifts from the ON state to the OFF state, and vice versa. With finite-difference time-domain method optimization, the proposed switch shows an extinction ratio of 18 dB at 1547.4 nm. The insert losses at the ON and OFF states are both less than 1 dB. The proposed switch unit has the potential to build an N × N switch matrix.

Characteristic's analysis of associative switching system

This paper introduced new method and model of telecommunication switching system design which can be applied to wavelength-division multiplexing (WDM) optical networks, circuit-switching networks or virtual channel/path connections in an asynchronous transfer mode (ATM) networks. Modern data switching systems such as electronic private branch exchange (PBX), routers and switches include switching matrix which are constructed in the form of bipartite graphs. In such systems, the issues of requests’ processing are considered from the queuing theory point of view. Associative switching systems are fundamentally new structures, therefore it is necessary to develop adequate methods for their throughput determination. Article covered matters of throughput determination basics of an associative switching system and the obtained formulas used for state probability calculation of switching modules and system throughput.

Limited-Information Signal De-Embedding for a Grain Bin Electromagnetic Imaging System

Measurements taken with a Vector Network Analyzer (VNA) are often corrupted by the presence of 2-port networks such as cables or amplifiers between the VNA and device-under-test (DUT). These 2-port devices are an essential part of the signal path, but distort the desired measurements. These distortions are commonly removed by de-embedding the 2-port networks between the VNA and DUT. Herein we consider the case of a grain bin electromagnetic imaging system where the DUT (the grain bin) is connected to the VNA by a set of amplifiers, a switching matrix, and locally installed cables. Further, for cost savings, the VNA only measures the S21 and S11 scattering parameters. Applying traditional de-embedding techniques to such a system would require a full S-matrix measurement, as well as knowing full 2-port parameters of all system components between the VNA and DUT. As these grain imaging systems have cables cut to length on site and are located in remote locations, it is not possible to obtain full 2-port measurements of the networks between the VNA and the DUT. Herein, we present an algorithm for using de-embedding techniques on such a system that allows us to approximate the various network parameters needed, and show that these approximations allow us to de-embed the grain bin measurements. Experimental results from one bin show that de-embedding reduces the average S21 errors in magnitude to less than 0.5 dB, with average phase errors of less than 0.15 radians. The average magnitude errors are similar to the measurement error between two different VNAs. A second experiment on a grain bin where the authors did not have physical access, shows that de-embedding the signal improves the computational model of the signals (a key indicator for future imaging success).

28–38-GHz 6-bit Compact Passive Phase Shifter in 130-nm CMOS

In this letter, a highly compact, bidirectional, wideband 6-bit resolution passive phase shifter (PS) is presented in low-cost 130-nm CMOS technology. A compact Lange differential hybrid is designed in this letter to provide quadrature signals from the input. The compact Lange hybrid is followed by a switching matrix that generates weighted sums of the quadrature signals to cover 360° and additional controlled loss using single pole single throw (SPST) switches. The matrix consists of 12 transistors, each of which is controlled by a three-level gate voltage (0, 0.6, and 1.2 V) providing higher resolution in phase shifts. The chip achieves the state-of-the-art performance with 10-dB insertion loss across 28–38 GHz. The chip also achieves an rms gain error of 0.6 dB and an rms phase error of 3° in the bandwidth, consuming no dc power and only 0.15 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> including baluns.

Time-Optimal Velocity Tracking Control for Consensus Formation of Multiple Nonholonomic Mobile Robots.

The problem of velocity tracking is considered essential in the consensus of multi-wheeled mobile robot systems to minimise the total operating time and enhance the system’s energy efficiency. This study presents a novel switched-system approach, consisting of bang-bang control and consensus formation algorithms, to address the problem of time-optimal velocity tracking of multiple wheeled mobile robots with nonholonomic constraints. This effort aims to achieve the desired velocity formation in the least time for any initial velocity conditions in a multiple mobile robot system. The main findings of this study are as follows: (i) by deriving the equation of motion along the specified path, the motor’s extremal conditions for a time-optimal trajectory are introduced; (ii) utilising a general consensus formation algorithm, the desired velocity formation is achieved; (iii) applying the Pontryagin Maximum Principle, the new switching formation matrix of weights is obtained. Using this new switching matrix of weights guarantees that at least one of the system’s motors, of either the followers or the leader, reaches its maximum or minimum value by using extremals, which enables the multi-robot system to reach the velocity formation in the least time. The proposed approach is verified in a theoretical analysis along with the numerical simulation process. The simulation results demonstrated that using the proposed switched system, the time-optimal consensus algorithm behaved very well in the networks with different numbers of robots and different topology conditions. The required time for the consensus formation is dramatically reduced, which is very promising. The findings of this work could be extended to and beneficial for any multi-wheeled mobile robot system.

Artificial Adaptive and Maladaptive Sensory Receptors Based on a Surface-Dominated Diffusive Memristor.

A biological receptor serves as sensory transduction from an external stimulus to an electrical signal. It allows humans to better match the environment by filtering out repetitive innocuous information and recognize potentially damaging stimuli through key features, including adaptive and maladaptive behaviors. Herein, for the first time, the authors develop substantial artificial receptors involving both adaptive and maladaptive behaviors using diffusive memristor. Metal‐oxide nanorods (NR) as a switching matrix enable the electromigration of an active metal along the surface of the NRs under electrical stimulation, resulting in unique surface‐dominated switching dynamics with the advantage of fast Ag migration and fine controllability of the conductive filament. To experimentally demonstrate its potential application, a thermoreceptor system is constructed using memristive artificial receptors. The proposed surface‐dominated diffusive memristor allows the direct emulation of the biological receptors, which represents an advance in the bioinspired technology adopted in creating artificial intelligence systems.

Повышение скорости регистрации эхосигналов ультразвуковой антенной решеткой за счет оптимального прореживания коммутационной матрицы с помощью генетического алгоритма

To increase the speed of recording echo signals and increase the speed of image recovery of reflectors, it is proposed to use a thinned switching matrix (SMC). To obtain a switching matrix that allows to obtain images minimally different from the image obtained by the full switching matrix (FMC), it is proposed to use a genetic algorithm. Two variants of optimization of the switching matrix are considered: element-wise thinning and column thinning. Numerical and model experiments have shown that a thinned switching matrix determined using a genetic algorithm, filled by 25%, allows the formation of images that differ from the image obtained by FMC, with an error of about 3%. Working with the switching matrix by columns allows you to increase the speed of recording echo signals by 4 times. The speed of image recovery increases by the same number of times.

M × N electrically controlled optofluidic matrix switch.

A completely non-blocking M×N electrically controlled optofluidic matrix switch that uses a 1×3 optical switch with a V-shaped microchannel as the switching unit is proposed. Its light paths and output ports are selected by a micro-actuator matrix and a control circuit. There are few reports of optofluidic matrix switches. Here the given electrostatic micro-actuator and the basic switch structure provide an effective feasible manner for the matrix switch due to the simple and compact structure as well as the operation style. The impacts of microchannels and intersecting waveguides on the switch performance are discussed, and multiple optimization schemes are proposed to reduce the insertion loss efficiently and significantly. The research results indicate that the M×N matrix switch has the advantages of good matrix controllability, simple structure, wide waveband (400-1700 nm), negligible polarization-dependent loss, small insertion loss, and low cross talk. For 1550 nm wavelength, the insertion loss of a 2×6 matrix switch is about 0.17-0.55 dB, and the maximum cross talk is less than -26.8dB. In addition, the performance parameters of a 4×8 matrix switch are given and compared with other reported matrix switches. The proposed M×N matrix switch solves the problem of large insertion loss of general optical matrix switches and can be expanded to a large-scale matrix switch. Moreover, the design of multiple output ports has more flexible applications in systems with multiple branch optical paths and network nodes.

Ultra-wide band (O to L) photonic integrated polymer cross-bar switch matrix.

We present an ultra-wide band photonic integrated 4×4 polymer cross-bar switch matrix based on total internal reflection and the thermo-optic effect. The photonic integrated polymer switch owns low insertion loss, low power consumption, wavelength, and polarization-independent operation for all switching paths. The experimental results show ultra-wide band (O- to L-band) operation with fiber-to-fiber insertion losses ranging from -3.7 to -6.5dB, 0.1 to 0.6 dB polarization-dependent losses, switching the on-off ratio above 36 dB on average, and 25 mW power consumption per path. Error-free operation with a power penalty <0.2dB at 1 E-9 bit error rate (BER) for ultra-wide band non-return-to-zero on-off keying (NRZ-OOK) wavelength-division multiplexing (WDM) switched signals at 10, 25, 40, and 50 Gbit/s, and 510 Gbps dual polarization 64-QAM switched data with a negligible penalty were measured.

Generalized One-Dimensional Parallel Switching Matrices With an Arbitrary Number of Beams

This paper introduces a novel family of one-dimensional switching matrices, also known as beamforming networks (BFNs), which can be sized for an arbitrary number of beams. It also describes the associated numerical design method, supported by several design examples. The concept is further validated with a full-wave model of a generic 5 × 5 switching matrix designed at 76 GHz. The proposed matrices are obtained by cascading units consisting of a two-way coupler and a phase shifter in a parallel configuration, providing theoretically lossless operation as a direct consequence of the orthogonal BFN topology and equalized path lengths, expected to benefit the frequency bandwidth. The design method is general, also including the configurations equivalent to Butler matrices when the number of beams is a power of two. The obtained planar matrix designs combine some benefits of the well-known Butler and Nolen matrices, namely the parallel topology and the arbitrary number of beams. The minimum number of cascaded units required by the proposed topology, also corresponding to the number of layers, is found to be <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$N$</tex-math></inline-formula> , where <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$N$</tex-math></inline-formula> is the number of beams, which is less than the number of cascaded units for the corresponding “parallel” Nolen matrix, for <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$N$</tex-math></inline-formula> larger than three, thus providing a reduction in the number of layers of up to 38% for an 8-beam matrix. This reduction is close to the theoretical upper boundary of 50%, reached for large values of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$N$</tex-math></inline-formula> . This significant reduction is expected to have a positive impact on RF performance, and in particular insertion losses, as well as amplitude and phase dispersion over the operating band. Interestingly, the proposed switching matrix configuration reduces to a standard Butler matrix when the number of beams is equal to 4, and demonstrates a reduction in the number of layers of 20% over the corresponding planar Butler matrix for a design with 8 beams. The proposed matrix configuration is a promising solution for the design of low-cost single-layer beam-switching matrices.

Followed The Regularized Leader (FTRL) prediction model based photovoltaic array reconfiguration for mitigation of mismatch losses in partial shading condition

Non-uniform irradiance, for example, partial shading, would affect the performance of the whole Photovoltaic (PV) array and reduce the output power. Since the layout of PV array is also an important factor influencing the performance of PV array, reconfiguration scheme has been researched popularly. Since plenty of array reconfiguration techniques are not realistic to be implemented in reality, in this paper considering the simplicity, robustness and economical aspects, a Followed The Regularized Leader algorithm (FTRL) regression prediction model based switches controlled PV array reconfiguration method is proposed to enhance the power output from solar PV array and alleviate the effects of partial shadings. The proposed scheme has no additional labor and wire requirement, since the proposed connection architecture of PV array involves no complex switch matrix design. Subsequently, to testify the performance of the proposed scheme, simulations with various shades in different PV arrays are made and evaluation parameters, for example, Fill Factor (FF) and mismatch loss are calculated. Furthermore, outdoor experiments are conducted to validate the simulation and the analyses. Besides, extensive analyses of cost analysis and energy savings are given. At last, a comprehensive evaluation is performed to check the quality of the proposed scheme by comparing with various techniques in literature.

Semantic Coding and Model Reconstruction of Multifunction Radar Pulse Train

Retrieving the working modes of multifunction radar from electronic reconnaissance data is a difficult problem, and it has attracted widespread attention in the field of electronic reconnaissance. It is also an important task when extracting benefits from big electromagnetic data and provides straightforward support to applications, such as radar type recognition, working state recognition, radar intention inferring, and precise electronic jamming. Based on the assumption of model simplicity, this study defines a complexity measurement rule for multifunction radar pulse trains and introduces the semantic coding theory to analyze the temporal structure of multifunction radar pulse trains. The model complexity minimization criterion guides the semantic coding procedure to extract radar pulse groups corresponding to different radar functions from pulse trains. Furthermore, based on the coded sequence of the pulse train, the switching matrix between different pulse groups is estimated, and the hierarchical working model of multifunction radars is ultimately reconstructed. Simulations are conducted to verify the feasibility and performance of the new method. Simulation results indicate that the coding theory is successfully used in the proposed method to automatically extract pulse groups and rebuild operating models based on multifunction radar pulse trains. Moreover, the method is robust to data noises, such as missing pulses.

Ultralow-VπL Silicon Electro-Optic Directional Coupler Switch With a Liquid Crystal Cladding

An ultralow-V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">π</sub> L photonic switch device is demonstrated utilizing the high optical and electrical field confinement in silicon slot waveguides coupled with the strong electro-optic response of nematic liquid crystals. A silicon photonic directional coupler switch with a modulation efficiency of 0.0195 V·mm and a loss-efficiency product of 0.0624 V·dB is achieved. The 1.5 mm long device is based on two-mode interference within a single slot waveguide resulting in a V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">π</sub> of 0.013 V and an extinction ratio of ~ 9dB at 1550 nm wavelength. The power consumption of the photonic switch is estimated to be below 0.6 nW and it possesses a response time of <; 1.5 ms. A comparative performance study between the directional coupler switch and a Mach-Zehnder Interferometer (MZI) switch is performed. The directional coupler switch is projected to have a smaller footprint and lower optical loss compared to a similar design MZI switch making it a strong candidate for switch matrix designs and applications.