Arbitrary Power Splitting Ratio Research Articles

MEMS‐enabled Ultralow Power Consumption Programmable Arbitrary Order Mode Switch

AbstractMode‐division‐multiplexing (MDM) recently attracted much interest due to its ability to enhance the capacity for optical information communication. To meet growing data transmission demands and enable flexible on‐chip mode manipulation, programmable optical mode converter switches are essential. This work introduces a micro‐electromechanical‐system (MEMS)‐enabled programmable arbitrary order mode switch, capitalizing on the benefits of MEMS technology such as low power consumption, robust modulation capabilities, and seamless large‐scale integration. Employing newly developed MEMS‐tunable mode converter (MTMC) units, the system achieves high conversion efficiencies from the fundamental mode to arbitrary higher‐order modes and supports programmable power distribution among different modes by cascading multiple MTMCs. As a proof‐of‐concept, a programmable TE0–TE0/1/2 mode switch operates in the 3.64 to 3.71 µm wavelength range, achieving maximum crosstalk values of –9.56 and –9.88 dB for TE0 to TE1 and TE0 to TE2 mode conversion, respectively, and a remarkably low power consumption of 67 pW. Furthermore, a programmable mode multiplexer is developed by simultaneously actuating two MEMS actuators to modulate phase matching conditions, enabling arbitrary power splitting ratios among these modes. The demonstrated scalability and flexibility of the proposed system highlight its potential as a foundational component for MDM systems.

Design and validation of a miniaturized reconfigurable power divider with arbitrary power split ratio and flexible output phase difference

This study introduces a microstrip line (ML) based reconfigurable 5-port power divider (PD) capable of manipulating power ratios at four output ports. The proposed PD offers two operational modes: unidirectional and bidirectional. In unidirectional transmission mode, the entire source power is directed to a particular output port, while in bidirectional transmission mode, the source power is equally distributed between two output ports. The selection of different transmission modes is accomplished by configuring six adaptive loads that are coupled to the PD structure, and the corresponding S-parameters of the proposed PD are derived by even–odd mode modeling. The resulting data is subsequently optimized by a numerical approach to identify the required design parameters that would ensure optimal performance. The proposed PD resonates at 1.06GHz and covers a frequency range spanning 0.9GHz to 1.2GHz, making it an excellent option for supplying regulated power to multi-port antennas or multiple input multiple output (MIMO) antennas proposed for aircraft navigation applications. The prototype has been developed to validate the notion of reconfigurable reactive loads utilizing varactor diodes and the recorded result is evaluated with the simulated results. The findings confirm excellent performance with regards to insertion loss (with a difference of <-2dB from the optimal values), reflection coefficient (≥-20dB), and isolation (≥-40dB) between the transmitting (input port) and non-transmitting or the remaining ports.

Low-loss and broadband arbitrary ratios 1 × 2 power splitter based on asymmetrically tapered multimode interference

This work presents a low-loss and broadband 1 × 2 power splitter with arbitrary power splitting ratios (PSRs) based on asymmetrically tapered multimode interference. The asymmetrically input tapered waveguide is employed to gradually alter the direction of light propagating in the multimode region. Experimental results show that the device can maintain low losses (∼0.2–0.4 dB) with adjusted PSRs ranging from 50%:50% to 75%:25% at 1550 nm. The adjustable range of PSRs can be extended by increasing the asymmetry of the structure. Additionally, its performance is weakly dependent on wavelength within the range of 1530–1565 nm. Benefiting from the gradual alteration of the direction of light propagation, the device exhibits a low output phase difference of ±8.7°, and the maximum phase deviation is below 6.2° over the wavelength range from 1500 nm to 1600 nm.

Ultracompact and ultrabroadband arbitrary ratio power splitter using subwavelength gratings

An ultracompact and ultrabroadband arbitrary ratio power splitter based on adiabatically tapered silicon waveguides, with subwavelength gratings in the coupling region, is proposed and demonstrated experimentally. Various power splitting ratios (PSRs) can be implemented by flexibly manipulating the gap of two adjacent tapered waveguides. The wavelength dependence is greatly reduced by introducing subwavelength gratings. Simulation results show that our proposed device has a 400 nm (1300 nm–1700 nm) bandwidth with an insertion loss &lt;0.5dB for PSRs of 50:50, 60:40, 70:30, 80:20, and 90:10, and the corresponding total device length is only 2.9 µm. The experimental results indicate that the insertion loss is lower than 0.82 dB over a wide bandwidth of 80 nm, and there is a PSR variation less than 2.5% in the range of 1530 nm to 1610 nm.

Arbitrary ratio power splitter based on shape optimization for dual-band operation

Arbitrary ratio power splitters (ARPSs) are essential components in integrated photonics. However, most existing ARPSs are limited to operating within a single wavelength band. To address this limitation, in this paper, we propose a 1 × 2 ARPS capable of operating in multi-wavelength bands using the shape optimization method. Harnessing a compact footprint of 14 μm × 1.7 μm, a series of dual-band ARPSs (DBARPSs) with varying power splitting ratios (PSRs) are designed. Within the wavelength ranges of 1280–1340 nm and 1520–1580 nm, all of the DBARPSs have an excess loss of less than 0.55 dB, with PSR deviations falling within the range of −0.5 dB to 1 dB. The practical viability is confirmed through a fabricated DBARPS with a 3 dB PSR. Experimental results show that the PSR deviation is within −0.8 dB to 1 dB, while the excess loss remains below 0.54 dB within the bandwidths of 1280–1340 nm and 1520–1580 nm. Additionally, the same design methodology is extended to develop a high-performance 1310/1550 nm wavelength demultiplexer. The resulting device showcases remarkable performance, with insertion loss below 0.7 dB and extinction ratios higher than 17 dB across the specified wavelength ranges. Experimental outcomes align closely with the design objectives, underscoring the dual-band operational capability and robust generality of the approach outlined in this paper.

Ultra-Broadband, Compact Arbitrary-Ratio Multimode Power Splitter Based on Tilted Subwavelength Gratings

Mode division multiplexing (MDM) technology is an effective solution for high-capacity optical interconnection, and multimode power splitters, as essential components in MDM systems, have attracted widespread attention. However, supporting a wide range of modes and arbitrary power splitting ratios with large bandwidth in power splitters remains a significant challenge. In this paper, we designed a power splitter based on a subwavelength grating (SWG) structure with tilted placement on a silicon-on-insulator (SOI) substrate. We achieve arbitrary TE0–TE9 mode-insensitive power distribution by altering the filling coefficient of the SWG. Thanks to our specific selection of cladding materials and compensatory design for the optical wave transmission and reflection shifts induced by SWG, our device demonstrates low additional loss (EL &lt; 1.1 dB) and inter-mode crosstalk (−18.8 &lt; CT &lt; −60 dB) for optical modes ranging from TE0 to TE9, covering a wavelength range from 1200 nm to 1700 nm. Furthermore, our proposed device can be easily extended to higher-order modes with little loss of device performance, offering significant potential in MDM platforms.

Transport of a topologically protected photonic waveguide on-chip

We propose a design on integrated optical devices on-chip with an extra width degree of freedom by using a photonic crystal waveguide with Dirac points between two photonic crystals with opposite valley Chern numbers. With such an extra waveguide, we demonstrate numerically that the topologically protected photonic waveguide retains properties of valley-locking and immunity to defects. Due to the design flexibility of the width-tunable topologically protected photonic waveguide, many unique on-chip integrated devices have been proposed, such as energy concentrators with a concentration efficiency improvement of more than one order of magnitude, and a topological photonic power splitter with an arbitrary power splitting ratio. The topologically protected photonic waveguide with the width degree of freedom could be beneficial for scaling up photonic devices, and provides a flexible platform to implement integrated photonic networks on-chip.

Ultra-Broadband, Compact Arbitrary Ratio Power Splitters Enabled by Adiabatic Sub-Wavelength Grating

An ultra-broadband, compact and CMOS-compatible arbitrary ratio power splitter that is based on a directional coupler is proposed on the silicon-on-insulator (SOI) platform. The proposed device consists of an adiabatic sub-wavelength grating (ASWG) and a conventional directional coupler. The wavelength dependence is greatly reduced by introducing an ASWG in the coupling region of the directional coupler. Simulation results show that our proposed device has an operating bandwidth of 250 nm for arbitrary power splitting ratios, with a transmission power variation of less than 8.5%, covering the wavelength range from 1400 nm to 1650 nm. Meanwhile, the device footprint has been narrowed to less than 46 μm. In addition, the power splitters also exhibit a low excess loss of below 0.24 dB. Our proposed ASWG-assisted power splitters show excellent potential for application in large-scale photonic integrated circuits.

Ultra-broadband dual-polarization and arbitrary ratio power splitters based on Bezier curve optimized multimode interference

We propose and demonstrate two types of 1 × 2 power splitters based on multimode interference (MMI), which are ultra-compact, fabrication friendly, and low loss. The contours of MMI and output tapers are optimized with Bezier curves, which can implement arbitrary ratio power splitters (ARPSs) and ultra-broadband dual-polarization power splitters (UDPSs). For ARPSs, the experimental results show that arbitrary power splitting ratios can be obtained with an average excess loss (EL) of 0.17 dB at 1550 nm for fundamental TE polarization. For UDPSs, the experimental results show that the ELs for fundamental TE and TM polarization are less than 0.63 dB and 0.44 dB over a large bandwidth of 415 nm (1260-1675 nm). The footprints of the proposed devices are less than 10 µm × 2.5 µm (without input straight waveguide) with large fabrication tolerance.

Compact, ultrabroadband and temperature-insensitive arbitrary ratio power splitter based on adiabatic rib waveguides.

We propose a compact, ultrabroadband and temperature-insensitive adiabatic directional coupler based on rib silicon waveguide-enabling arbitrary splitting ratios. Simulation results show that the device can achieve arbitrary splitting ratios from 1400 to 1600nm, equal to 50%:50%, 60%:40%, 70%:30%, 80%:20%, and 90%:10% for the fundamental transverse electric mode. The designed device has an excess loss of less than 0.19dB on the operational waveband. Furthermore, the proposed device shows a great robustness to fabrication imperfection, with a waveguide width deviation of 50nm and ambient temperature change from 0°C to 200°C. These properties make the design a potential candidate for ultrahigh-density photonic integration chips.

IMPROVEMENT OF ENERGY COLLECTION EFFICIENCY IN MOBILE SENSOR NETWORKS

A proposed technique for increasing the lifespan of mobile wireless sensor networks that are energy constrained is provided in this paper. This technique is based on the idea that radio frequency (RF) signals simultaneously carry information and energy. Thus, the lifespan of a wireless network can be greatly increased by improving the efficiency of energy harvesting from RF signals. This technique's simultaneous wireless information and power transfer allows relay nodes to gather energy for use in wireless data transfer. At the receiver side, the transmitted RF energy can be recycled to lengthen the life of the mobile wireless network. Conversely, to maximize the system's overall effectiveness, a balance between energy harvesting and wireless data transfer is necessary. In the suggested method, the received power is divided into two continuous sets of power streams using arbitrary power splitting ratios. A resource allocation (ResAll) method is used to identify the resource allocation values by taking into account the various power splitting capacities of receivers. The ResAll algorithm system balances the data rate, energy efficiency, power splitting ratio, and transmitted power to achieve energy efficiency. The best resource allocation strategies are then obtained using particle swarm optimization (PSO), which maximizes the system energy efficiency. In the process, a cost function is created and PSO maximizes the energy efficiency by optimizing the cost function's solution with regard to the restrictions applied during iterations.

Dual-Band Dual-Mode Dielectric Resonator Filtering Power Divider With Flexible Output Phase Difference and Power Split Ratio

The design of dual-band filtering power divider based on dual-mode dielectric resonator (DR) is investigated. The external quality factors ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$Q_{e}$ </tex-math></inline-formula> ) of two modes can be controlled independently, which makes the design procedure for arbitrary power split ratio simple and efficient. Meanwhile, the phase difference between the output ports can be adjusted to be in-phase or out-of-phase by altering the quadrants where the feeding probes are located. To improve the band-to-band isolation, the generation mechanism of the transmission zero between the two bands has been analyzed. Based on the analysis, the dual-band filtering power dividers with in-phase/out-of-phase outputs and equal/unequal power split ratio are proposed. All of them can be easily built by properly changing the location or the length of the feeding probes without increasing the circuit size. To verify the design concept, the above-mentioned prototypes are simulated. Some of them are implemented and measured. The measured results match well with the simulated responses, showing good performance, such as low loss and good band selectivity.

General design of N-way Bagley power dividers with arbitrary unequal output power splitting ratios using a new iterative algorithm

ABSTRACT The general design of N-way Bagley Power Divider (BPD) with unequal output power splitting ratio is presented through this paper for the first time. Design equations are systematically derived based on microwave engineering, transmission line, and circuit theories after considering perfect input port matching (theoretically S 11 = 0). An iterative algorithm for computing the characteristic impedances of the lines between adjacent output ports and the scattering parameters (S-parameters) for N-way BPD design is developed in this article. For validation, two multi-port examples, 11-way BPD and 13-way BPD are presented to confirm the design procedure. S-parameters have been calculated theoretically and using the presented algorithm to find the value of the design impedances. After that, these values are evaluated using both ADS and HFSS. A detailed flowchart is given through this paper to implement this N-way BPD iterative algorithm for any output port number (N). A very good agreement between theoretical, simulated, and experimental results is noted. This indicates the accuracy of the presented algorithm and the derived design equations. Besides, it gives the flexibility to design BPDs with any odd number of output ports for arbitrary output power splitting ratio, which is considered as a tangible additive in BPD design.

Broadband Arbitrary Ratio Power Splitters Based on Directional Couplers With Subwavelength Structure

We propose and demonstrate a 1×2 power splitter enabling arbitrary power splitting ratios. The device is based on a directional coupler with subwavelength structure in the coupling region and a trapezoid-structure in one arm. The measurement shows that arbitrary power splitting ratios, equal to 50:50, 60:40, 70:30, 80:20 and 90:10, can be obtained over an >80 nm bandwidth with an excess loss about 0.65 dB at 1550 nm, while the footprint is only 11.5 μm ×1.315 μm. The proposed arbitrary ratio power splitter shows promising application prospect in photonic integrated circuits.

Compact, broadband, and low-loss silicon photonic arbitrary ratio power splitter using adiabatic taper.

The arbitrary ratio power splitter is widely used in photonic integrated circuits (PICs), for signal monitoring, power equalization, signal feedback, and so on. Here we designed a fabrication-tolerant, compact, broadband, and low-loss arbitrary ratio power splitter. The proposed arbitrary ratio power splitter was realized with an adiabatically tapered silicon rib waveguide with 70 nm shallow etches and an Si3N4 waveguide. The fabrication analysis confirmed that both of them are robust to fabrication errors. 3D finite-difference time-domain simulations show a very low excess loss (less than 0.02 dB for Si3N4 waveguide and 0.05 dB for Si rib waveguide), and a broadband operating wavelength range (100 nm). Good fabrication tolerance and standard critical dimensions make the arbitrary ratio power splitter compatible with the standard fabrication process of commercial silicon photonic foundries.

Arbitrary power-splitting-ratio achieved in 1×2 hybrid plasmonic multimode interference device by structure symmetry broken

The power-splitting-ratio (PSR) of the 1 × 2 multimode interference (MMI) device based on hybrid plasmonic waveguide is studied theoretically. Other than the finite and fixed PSR in conventional MMI, by rational breaking the symmetry of the structure, arbitrary PSR can be achieved, while the original advantages of MMI devices including large fabrication tolerance, wide operation bandwidth, and compact size (1 × 1.1–1.5 μm2) are well-kept. Besides, unlike the regular hybrid-plasmonic-waveguide based device suitable only to TM polarization, the power splitter design presented here could be also possible available to TE polarization incidence. Introducing tapered structure may further improve its performance on both TE and TM polarization cases.

Ultra-broadband on-chip multimode power splitter with an arbitrary splitting ratio

The multimode power splitter is a basic component in mode-division multiplexing systems. In this paper, we propose an ultra-broadband silicon multimode power splitter enabling arbitrary power splitting ratios. The proposed multimode splitter is designed based on a waveguide crossing with an obliquely embedded subwavelength grating (SWG) transflector. The incident multiple guided-modes can be split into two beams with low excess losses and low crosstalk by the SWG transflector where the thin-film interference effect happens. As an example, a silicon multimode power splitter is designed to work with the three lowest-order modes of TE polarization. Any desired splitting ratio ranging from 0% to 100% can be achieved by engineering the structural parameters of the SWG. Moreover, the desired splitting ratio can be very uniform over an extremely broad bandwidth of ≥ 415 nm, covering O-, E-, S-, C-, L- and U-bands. The intermodal crosstalk is &lt; −20 dB for all the input modes in theory. To the best of our knowledge, the proposed structure is the first multimode power splitter enabling any desired power splitting ratios in all the optical communication bands.

Robust arbitrary ratio power splitter by fast quasi-adiabatic elimination in optical waveguides.

We propose a method for the robust splitting of light between the two outer waveguides in a three-waveguide system by mode evolution. Arbitrary power splitting ratio is achieved by engineering the spacings between the middle waveguide and the outer waveguides. Coupling of light into the middle waveguide is suppressed by the adiabatic elimination scheme. To speed up the adiabatic passage in the effective two-mode system involving only the outer waveguides, we introduce the fast quasi-adiabatic dynamics protocol, leading to a shortcut to adiabaticity. Using the proposed fast quasi-adiabatic elimination scheme, power splitters with various power splitting ratios including, 10/90, 20/80, 30/70, 40/60, 50/50, 60/40, 70/30, 80/20, and 90/10, are designed. Simulations show that the splitters have good robustness against wavelength and fabrication variations.

Broadband, low-loss silicon photonic Y-junction with an arbitrary power splitting ratio.

Photonic integrated circuits (PICs) often require broadband power splitters such as Y-junctions for signal monitoring, signal feedback, power distribution, etc., with various splitting ratios. Therefore, a parameterized Y-junction with an arbitrary power splitting ratio that can be selected in layout design is desired in a PIC library. Here, we propose an ultra-compact (1.4 μm × 2.3 μm) Y-junction on the 220-nm-thick silicon-on-insulator (SOI) platform for an arbitrary splitting ratio with a programmable design. It applies smooth curvatures for a good tolerance to fabrication errors. Rigorous 3D-FDTD simulations predict an excess loss below 0.36 dB and a splitting-ratio variation of less than 1 dB over 100 nm. Experimental results achieved using a CMOS-compatible silicon photonics process show an excess loss of lower than 0.5 dB for a splitting ratio varied from 0 to -18 dB across the entire C band. Both numerical and experimental results show that the power splitting ratio of the proposed device is weakly wavelength dependent.

Theory and Experiment of Multiport Filtering Power Divider With Arbitrary Division Ratio Based on Dielectric Resonator

This paper presents a novel and simple design approach of multiport power divider with arbitrary power splitting ratio as well as filtering response. The relationship between the external Q -factors ( Q es) and power splitting ratio is theoretically analyzed, and it is found that the power allocation for the multiple outputs is determined by their Q e's ratio. By altering the Q es of the splitting ports, the power ratio can be arbitrarily controlled while the output total Q e is equal to the input Q e. Based on this, the two functions of power division and bandpass response of the proposed filtering divider can be designed independently. Accordingly, two practical three-way filtering power dividers with different division ratios (1:1:1 and 3:1:1) using the same topology based on the dielectric resonator (DR) are constructed for the first time. Both of them can be easily built by properly changing the lengths of feeding probes for the output DR without increasing the circuit size, while the phase difference between the splitting ports mainly depends on the direction of the feeding probes. To verify the proposed design concept, the two filtering power dividers with different division ratios mentioned above are implemented and measured. Comparisons of the measured and simulated results show good accordance and verify the theoretical predications.