A squintless slot-antenna array (2-D), built on a single substrate integrated waveguide (SIW) is shown. The effort needed for designing a suitable feeding network in SIW technology is justified in ...view of obtaining lightweight, low-profile, and low-cost antennas for many applications, including direct broadcast satellite. A proper definition of an "H"-shaped subarray, made of four slot-pairs, is used to improve the input matching over a wide band. This choice allows remarkable simplification of the fabrication process, as the slots are cut directly in one of the metallic planes forming the SIW.
This paper presents a novel design of a curve tapered leaky-wave antenna (LWA). An FDTD code was used to extract the propagation constant of a microstrip LWA and to run a simple algorithm to design ...its layout. A physical grounding structure along the length of the antenna allows the adoption of a simple feeding planar line and the reduction of sidelobes. Moreover, the proposed design of LWA has interesting performance both for its bandwidth, (up to 33% for VSWR< 2) and for its gain (more than 12 dBi peak power gain at 10.5 GHz), compared with conventional planar microstrip LWAs which work in the same frequency range but with narrower bandwidth (20% VSWR< 2) and peak power gain less than 10 dBi. A prototype of a LWA proposed, was made showing a good agreement between experimental and theoretical results.
Processing of EMC data with factor analysis Losito, O.; Audone, B.; Dimiccoli, V.
2015 IEEE International Symposium on Electromagnetic Compatibility (EMC),
08/2015
Conference Proceeding, Journal Article
Large amount of data are obtained from simulation or experimental activities. In most cases they are not of easy interpretation; factor analysis provides a tool to highlight those situations of major ...interest in EMC related to interaction mechanisms between electrical, geometrical and mechanical parameters. The case of field to cable coupling, a typical immunity problem, is presented to illustrate the procedure which can easily be extended to more complex situations including conducted and radiated emission patterns.
The use of metal foam continues to grow in terms of research and application. Recently, new developments in the electromagnetic (EM) environment, such as shielding applications, have been proposed. A ...model of metal foam shielding is developed and discussed in this paper to characterize and simulate the EM shielding behavior. More specifically, the EM characterization has been considered, and experimental shielding effectiveness measurements have been performed. These new double wire-mesh screens, obtained as a development of previously planar shields, allow the design of metal foam EM shields, showing good agreement results among this model, some prototype of this model, and metal foams. The good agreements among data pave the way to improve the model for the low-frequency metal foams behavior.
A mid-IR lasing system based on a tapered fiber coupled to an Er 3+ -doped microsphere has been modeled and numerically investigated. In order to design and optimize the device performance, a ...dedicated 3-D numerical code exploiting the coupled mode theory and the rate equations model has been developed. The main energy level transitions among the Er 3+ ions, the most relevant secondary ion-ion interactions, the amplified spontaneous emission, and the fiber-microsphere coupling phenomena have been taken into account. In order to optimize the lasing performance, several parametric simulations have been carried out. The obtained numerical results show that a laser threshold of about 55 mW and an output power of about -17.8 dBm can be obtained by using small microspheres.
A mid-IR lasing system based on a tapered fiber coupled to an Er3+-doped microsphere has been modeled and numerically investigated. In order to design and optimize the device performance, a dedicated ...3-D numerical code exploiting the coupled mode theory and the rate equations model has been developed. The main energy level transitions among the Er3+ ions, the most relevant secondary ion-ion interactions, the amplified spontaneous emission, and the fiber-microsphere coupling phenomena have been taken into account. In order to optimize the lasing performance, several parametric simulations have been carried out. The obtained numerical results show that a laser threshold of about 55 mW and an output power of about -17.8 dBm can be obtained by using small microspheres.
The calibration of EMC antenna has always been a frustrating subject for most EMC laboratories. On the other hand in many cases EMC antennas are recalibrated when it is not strictly necessary. This ...paper proposes a procedure to establish when EMI antennas shall be calibrated on the basis of technical considerations without making reference to abstract quality assurance rules. It seems more correct to stipulate the definition of the calibration time intervals on the basis of a statistical approach comparing the past performance characteristics with the present ones. The reflection coefficient at the antenna input terminal is monitored over the frequency range of interest at regular time intervals to detect whether a modification has occurred; only if this modification is beyond the assumed tolerance limits the antenna shall be calibrated. The procedure illustrated in this paper is in line with the well accepted use of control charts described in quality assurance documents; it has been modified from the standard methods to take into account the specific characteristics of EMI antennas.
Plasmids are used in the biopharmaceutical industry for the production of recombinant proteins, recombinant DNA for DNA vaccines and as non-viral vectors for gene therapy. Antibiotic- resistance ...genes are used for plasmid selection and to ensure plasmid maintenance. Regulatory bodies like the European Medicines Agency have introduced guidelines to limit the use of antibiotics and their resistance genes in the manufacture of therapeutics. Therefore, it is important to develop novel, effective methods for antibiotic-free plasmid selection. Cobra Biologics has designed a novel mechanism for antibiotic-free plasmid selection called oriSELECT. oriSELECT uses RNAI and RNAII, the antisense RNAs of the pMB1 plasmid origin of replication (ori) as the selectable marker. These two RNAs are involved in replication and its control of almost all plasmid vectors used commercially and academically. By placing the RNAII sequence in the E. coli chromosome upstream of either a toxic gene or a repressor for an essential gene, cell growth should be inhibited. In cells containing a plasmid with the pMB1 replicon producing RNAI, transcription of the growth inhibitor is blocked allowing cell growth and survival. This work describes the testing of various cassettes useful for oriSELECT and the construction of oriSELECT strains.
Plasmids are used in the biopharmaceutical industry for the production of recombinant proteins, recombinant DNA for DNA vaccines and as non-viral vectors for gene therapy. Antibiotic- resistance ...genes are used for plasmid selection and to ensure plasmid maintenance. Regulatory bodies like the European Medicines Agency have introduced guidelines to limit the use of antibiotics and their resistance genes in the manufacture of therapeutics. Therefore, it is important to develop novel, effective methods for antibiotic-free plasmid selection. Cobra Biologics has designed a novel mechanism for antibiotic-free plasmid selection called oriSELECT. oriSELECT uses RNAI and RNAII, the antisense RNAs of the pMB1 plasmid origin of replication (ori) as the selectable marker. These two RNAs are involved in replication and its control of almost all plasmid vectors used commercially and academically. By placing the RNAII sequence in the E. coli chromosome upstream of either a toxic gene or a repressor for an essential gene, cell growth should be inhibited. In cells containing a plasmid with the pMB1 replicon producing RNAI, transcription of the growth inhibitor is blocked allowing cell growth and survival. This work describes the testing of various cassettes useful for oriSELECT and the construction of oriSELECT strains.
Plasmids are used in the biopharmaceutical industry for the production of recombinant proteins, recombinant DNA for DNA vaccines and as non-viral vectors for gene therapy. Antibiotic- resistance ...genes are used for plasmid selection and to ensure plasmid maintenance. Regulatory bodies like the European Medicines Agency have introduced guidelines to limit the use of antibiotics and their resistance genes in the manufacture of therapeutics. Therefore, it is important to develop novel, effective methods for antibiotic-free plasmid selection. Cobra Biologics has designed a novel mechanism for antibiotic-free plasmid selection called oriSELECT. oriSELECT uses RNAI and RNAII, the antisense RNAs of the pMB1 plasmid origin of replication (ori) as the selectable marker. These two RNAs are involved in replication and its control of almost all plasmid vectors used commercially and academically. By placing the RNAII sequence in the E. coli chromosome upstream of either a toxic gene or a repressor for an essential gene, cell growth should be inhibited. In cells containing a plasmid with the pMB1 replicon producing RNAI, transcription of the growth inhibitor is blocked allowing cell growth and survival. This work describes the testing of various cassettes useful for oriSELECT and the construction of oriSELECT strains.