PIN Switches Research Articles

Frequency reconfigurable circular microstrip G-slotted antenna with DGS for various wireless applications

Frequency reconfigurable circular microstrip G-slotted antenna with DGS for various wireless applications

Performance Analysis of Automated Air Pollution Removable System with Fire Indicator

Air pollution and aging populations are one of the most important issues facing in the development of all countries around the world. In this project work and effort has been made to develop a air pollution removable and fire indicated for fire work industry to safety purpose. The aim of this work is to develop a fire indicated and pollution removable that will use a collect fire work chemical powder around the working area. This model implies a conversion of rotary motion to the overall system. This motion is uses for chemical dust arrest by viscous liquid to all direction in the industry. In this model we can operate two pin switches for the clock wise and antilock wise direction. the gear motor is using to rotary motion. The rotary disk is mounted on the motor spindle. The tank is resting on the rotary disk. The exhaust fan is fitted in the top position of the tank. They are two way in the tank. One is inlet for suck the pollution air another one is outlet. Bottom of the tank dust despatch valve attached. The fire indicates system is mounted on the rotary disk plate vertically. After this work performance test to the working area. This research provides a new perspective and the health effect of air pollution.

Fabrication and Performance Evaluation of Air Pollutionremovable System with Fire Indicate for Fireworks Industry

Air pollution and aging populations are one of the most important issues facing in the development of all countries around the world. In this project work and effort has been made to develop a air pollution removable and fire indicated for fire work industry to safety purpose. The aim of this work is to develop a fire indicated and pollution removable that will use a collect fire work chemical powder around the working area. This model implies a conversion of rotary motion to the overall system. This motion is uses for chemical dust arrest by viscous liquid to all direction in the industry. In this model we can operate two pin switches for the clock wise and antilock wise direction. the gear motor is using to rotary motion. The rotary disk is mounted on the motor spindle. The tank is resting on the rotary disk. The exhaust fan is fitted in the top position of the tank. They are two way in the tank. One is inlet for suck the pollution air another one is outlet. Bottom of the tank dust dispatch valve attached. The fire indicates system is mounted on the rotary disk plate vertically. After this work performance test to the working area. This research provides a new perspective and the health effect of air pollution.

Cubic versus hexagonal SiC vertical pin SPST/SPDT/SPMT switches for MMW communication systems: a modified quantum drift-diffusion model for switching characteristics analysis

A modified quantum drift-diffusion (QDD) model is developed for non-linear analysis of SiC (4H, 6H and 3C polytypes) pin semiconductor diodes at W-band frequency regime. Effects of incorporation of a buffer layer (n-type), in between substrate and low doped active region of the hexagonal (4H and 6H) pin (p++-p+-n−-n-n++) vertical mesa structure is thoroughly studied in this paper for the improvement of MM-wave performance of the single device. Also, a thin layer of Ge has been introduced in between Si substrate and n+ cubic-SiC layer in 3C-SiC pin-device for minimising the lattice mismatch issue in between Si/3C-SiC interface. The comprehensive analysis establish that the forward characteristics, reverse recovery time (1 ns) and breakdown voltage (171 Volt) in case of 4H-SiC device are quite good in comparison to its cubic (3C) and other hexagonal (6H) counterparts, however, the switching characteristics of 3C-SiC pin diode array is comparatively better than its hexagonal counterparts. This observation could be explained in terms of lowest series resistance in 3C-SiC based single pin device that has been achieved by incorporating Ge layer in mesa structure. The authors have made a comparative analysis among SPST, SPDT and SPMT pin switches made up with 4H, 6H and 3C-SiC poly-types. At 94 GHz, W-band central frequency, series resistance in 4H-SiC single device is 0.59 Ω, whereas, the same is much lower (0.27 Ω) in case of 3C-SiC. Insertion loss and isolation in 3C-SiC pin array of switches are found to be 0.18 dB and 38 dB (SPST switch), 0.19 dB and 67 dB (SPDT switch), 0.20 dB and 90 dB (SPMT shunt type switching array) and 0.23 dB and 74 dB (SPMT series-shunt type switching array). This newly proposed QDD model validation is done through comparative studies between experiment and analytical results for 4H-SiC SPST switches in low-frequency Microwave region. The validated QDD model, coupled with PSpice and Comsol Multi-physics simulator, then used for designing of the W-band devices and corresponding switches. However, as far as author’s knowledge is concerned, no experiment is yet done with SiC pin diodes at W-band frequencies, in literature for comparison. From simulation point of view also such an extensive study on hexagonal and cubic SiC pin diode switches at W-band region has not yet been done by any other researcher group. This paper, for the first time, establishes the feasibility and potentiality of IV-IV group semiconductor based pin (p++-p+-n−-n-n++) switches for W-band applications. Comparative analysis also reveals that 3C-SiC based shunt type pin (p++-p+-n−-n-n++) SPMT switches are the best for MMW-communication systems. Thermal modelling of the designed devices are also compared and reported in this paper. The quasi-3D thermal analysis is done to optimize the mesa and heat-sink diameter/dimensions so as to minimize the thermal runaway issues. The results may further be used for developing low-cost and fast semiconductor switches for potential application in THz communication systems.

III–V super-lattice SPST/SPMT pin switches for THz communication: theoretical reliability and experimental feasibility studies

A physics-based Quantum-Modified CLassical Drift–Diffusion (QMCLDD) non-linear mathematical model has been developed for design and characterisation of GaN/AlGaN asymmetrical superlattice pin based single-pole single-throw (SPST) and single-pole multi-throw (SPMT) switches for sub-MM wave communication systems. The simulator has incorporated several important physical phenomena that arise in superlattice structure, including quantum confinement effects, generation-recombination and tunnelling generation of carriers as well as scattering limited carrier mobility and velocity in GaN/AlGaN structure. In order to reduce the dislocation density and in turn the series resistance in GaN/AlGaN heterostructure, thin AlN nucleation layer and a buffer layer are considered in the simulation. It is observed that the RF series resistance of the pin device, operating around 0.2 THz frequency regime, reduces in case of proposed superlattice structure. The advantages of super-lattice pin diode over the conventional Si devices are the faster reverse recovery time (~ 9 vs 35 ns) and lowering of forward RF series resistances (0.39 vs 1.20 Ω). This study also reveals that SPST and SPMT switches made up with super-lattice devices are characterized by low insertion loss (~ 0.13 and 0.15 dB, respectively) and high isolation (~ 65.4 and 82.5 dB, respectively). A good agreement between theory and experiment establishes the superiority of the present model over the others. A comparative analysis of Si and GaN/AlGaN super-lattice pin SPST and SPMT switches establishes the potential of the later for its application in high-frequency THz-communication. In addition to this, a detailed thermal modelling of the device has also been done to make the analysis more realistic. The junction temperature of the designed GaN/AlGaN superlattice pin switch will be as high as 377 K, which is quite moderate compared to its flat profile counterpart. To the best of authors’ knowledge, this is the first ever report on QMCLDD non-linear modelling of pin SPST and SPMT switches (series-shunt combination) at THz-arena.

A Novel Integrated Switchable Absorber and Radiator

First, a novel integrated structure with selectable absorbing and radiation capabilities is proposed, which consists of periodic arrays of metallic three-loop nested structure printed on a thin grounded dielectric slab. Lumped resistors with different values are fixed on each side of all three loops, while PIN switches are optionally fixed parallel to the lumped resistors on the specific loop. When the switches are turned off , the parallel lumped resistors become operational, the present integrated structure acts lossy and performs broadband absorption function. When switches are turned on , those parallel lumped resistors are shorted, the corresponding loop structure can be regarded lossless, acting as a patch antenna. Second, equivalent circuit models of the present structure of absorber and radiator are developed and analyzed, respectively, to explain the working principle of the present structure. Finally, a $3 \times 3$ periodic array of metallic three-loop nested structure printed on an F4B dielectric slab has been designed, fabricated, and measured. Both simulated and measured results show that the proposed design can obtain a high absorptivity over a broad frequency band. Meanwhile, by changing the PIN switches’ state, the present structure can achieve good radiations at specific frequencies.

ELECTRONICALLY RECONFIGURABLE BEAM STEERING ANTENNA USING EMBEDDED RF PIN BASED PARASITIC ARRAYS (ERPPA)

In this paper, an electronically reconflgurable beam steering antenna using embedded RF PIN switches based parasitic array (ERPPA) is proposed for modern wireless communication systems that operate at 5.8GHz frequency. In the proposed antenna, a single driven element is fed by a coaxial probe, while each of the two parasitic elements is integrated with an RF PIN switches that embedded inside the substrate. In the conventional reconflgurable antennas, the RF PIN switches are mounted on narrow slots created on the top or bottom layer of the radiator/parasitic elements, which could lead to the dimensional changes of the antenna and degrade the performance in terms of beam steering and return loss. However, this research proposes an exclusive solution where the RF PIN diodes at parasitic elements are embedded inside the substrate thus no additional slots have to be created to mount the SMCs on the antenna. In this regard, the proposed antenna is highly competent to eliminate the intermodulation efiect generated by the RF PIN diodes and the other passive elements associated with the PIN diodes. In this research, extensive investigations revealed that the parasitic element dimension and the selection of RF PIN switches signiflcantly in∞uence

Electromechanical controlled phased array dumbbell EBG beam steerer

A steerable phased array antenna driven mechanically is realized by utilizing the variation of dumbbell electromagnetic bandgap (EBG) structures. The variation takes place under the feed line of a 4-element array that gives the change in relative phase shift. The phase shift achieved from different shaping combinations of EBGs shifting under the feed lines. The feed lines are connected with four microstrip patches to yield a 4-element phased array antenna. The mechanical controlled pattern shapes of phase array antenna are simulated in electromagnetic (EM) software Zeland IE3D. Finally the design is fabricated with the help of optical lithography. It can be seen that the beam steering angle can be controlled mechanically without phase shifter and PIN switches.

Flexible microwave PIN diodes and switches employing transferrable single-crystal Si nanomembranes on plastic substrates

This paper reports the realization of flexible RF/microwave PIN diodes and switches using transferrable single-crystal Si nanomembranes (SiNM) that are monolithically integrated on low-cost, flexible plastic substrates. High frequency response is obtained through the realization of low parasitic resistance achieved with heavy ion implantation before nanomembrane release and transfer. The flexible lateral SiNM PIN diodes exhibit typical rectifying characteristics with insertion loss and isolation better than 0.9 dB and 19.6 dB, respectively, from DC to 5 GHz, as well as power handling up to 22.5 dBm without gain compression. A single-pole single-throw (SPST) flexible RF switch employing shunt-series PIN diode configuration has achieved insertion loss and isolation better than 0.6 dB and 22.9 dB, respectively, from DC to 5 GHz. Furthermore, the SPST microwave switch shows performance improvement and robustness under mechanical deformation conditions. The study demonstrates the considerable potential of using properly processed transferrable SiNM for microwave passive components. Future investigations on transferrable SiNMs will lead to eventual realization of monolithic microwave integrated systems on low-cost flexible substrates.

Highly miniaturised InP/InGaAs PIN MMIC switches using BCB-based multilayer technology

Fully integrated single-pole-double-throw and single-pole-triple-throw InP/InGaAs PIN switches have been designed and fabricated using a newly proposed BCB-based 3D MMIC technology. The chip sizes of the fabricated InP/InGaAs PIN switches, which show good and broadband RF characteristics, have been significantly reduced compared to those of conventional GaAs-based switches. The results indicate the potential of the proposed 3D MMIC technology for compact embedded MMIC applications.

A NOVEL SCHEMATIC FOR CALIBRATION OF LARGE PHASED ARRAY ANTENNA USING PROGRAMMABLE TIME-DELAY UNITS

In this paper, a conceptual schematic for calibration of large phased array antenna is presented. Derived from an earlier work by the authors, the presentation demonstrates a simple yet innovative schematic of inserting time delay units with each element in the array which can be used to generate both SUM and DIFFERENCE pattern. Both these patterns are electronically steerable. The calibration is done using SUM-DIFFERENCE pattern. PIN switches are used to insert proper time delay units. Thus the schematic is completely programmable using a microcontroller to control the insertion of time delay. The details of the schematic is presented along with the generated antenna patterns.

Current Induced Degradation of a-Si:H Pin and Schottky Switches

ABSTRACTForward-bias current stress experiments were performed on α-Si:H p-i-n and Schottky switches at several temperatures and at current densities up to 6 A/cm2. In Schottky diodes, current stressing results in a lowering of the forward-bias SCLC current together with an increase of its thermal activation energy. The reverse current is unaffected. The rate of degradation of the forward current increases with increasing temperature. From a comparison of the degradation behaviour of Schottky's with different barrier height we find that the rate of degradation is correlated to the minority-carrier injection ratio of the Schottky contact. The effects are interpreted as being due to metastable state creation in the bulk α-Si:H. The rectifying properties of the metal-to-semiconductor contact are relatively stable to current stress.The forward-bias I-V curves of p-i-n diodes degrade much faster than those of the Schottky switches. At the same time, the reverse-bias current increases due to the stress. The lower stability to current-stress of p-i-n diodes is ascribed to the much higher hole injection in the mesa. After a short time, the reverse-bias current becomes dominated by e-h generation from the created deep states in the i-layer and then gives a direct indication of its time dependence.

Phase noise measurement of a pulsed W-band IMPATT source

A test method is described that uses the Delay Line Bridge (DLB) discriminator as a phase modulation (PM)- or amplitude modulation (AM) detector. A brief discussion is given to explain the different measurement requirements for pulsed sources used in Doppler RADAR with stationary or slow moving transmitter platforms, and fast moving transmitter platforms. A practical solution is offered to the problem of inadequate isolation in present day W-band PIN switches. This measurement set-up, provides a direct measure of the level of spurious oscillations of the IMPATT source, the relative noise content in the turn-on and turn-off region of the RF pulse, and the phase ripple. It also illustrates the influence of reference source injection locking level on the measured characteristics.

Permanent Neutron Damage in PIN Microwave Diode Switches

The microwave PiN diode and its associated circuitry have been studied both experimentally and theoretically. The results of the study show that microwave PIN switches are very susceptible to permanent neutron damage. The failure mechanism is a severe reduction of conductivity modulation in the diode's I region caused by a reduction of carrier lifetime. This loss of conductivity modulation not only causes a reduction of the isolation abilities of a microwave switch but is also shown to lead to other secondary failure modes which can be extremely important.