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DESIGNING WAVEGUIDE FILTERS FOR COMMUNICATION DEVICES

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RF/Microwave filters find wide application in communication systems, such as satellite links or wireless base stations. Microwave filters are passive devices employed to select a specific band of the frequency spectrum. Depending on the spectral region that is selected or rejected, they are classified in low-pass filters, high-pass filters, band-pass filters or band-stop filters. Passive devices at the output stage of the communication system must be able to deal with very high power signals. Because of that, waveguide technology is the ideal choice to implement these devices. This work presents the design of a different kind of waveguide-based filter. Working Principle of Filter? So, what is magic behind filter? How does it reject signals and pass others? In order to understand this, let us first go through the concept of mismatch. When there is perfect impedance match between the input impedance of system with output load impedance, maximum energy transferred from input to outp

CAPACITIVE RF MEMS SWITCH DESIGN AND SIMULATION

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The switching is required in many applications at low as well as at high frequency. RF MEMS switches are the specific micro mechanical switches that are designed to operate at RF to mm-wave frequencies. MEMS switches usages some mechanical movement to achieve a closed or open circuit in the Radio Frequency transmission lines. GaAs FET switches do not have sufficient isolations to minimize cross interference and signal jamming from channels is close proximity.  MEMS switches provide  high isolation  when open,  low insertion loss  when closed, and can be operated at low power consumption. Because of electromechanical isolation, RF circuit doesn’t leak or couple significantly to the actuation circuit. MEMS are small in size hence it occupies less space in circuit designs so that which was the most required device in the communicating world. Radio Frequency Micro Electro Mechanical Switches (RF MEMS) classification depends on the type of actuation, deflection axis, contact type, circuit

QFN Package Simulation

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he Quad Flat No-lead (QFN) package is a CSP (plastic encapsulated package) with a copper lead frame substrate. QFN type package is one of the most cutting-edge IC packaging technologies in the electronics. The QFN is a leadless package where electrical contact to the PCB is made by soldering the leads on the bottom surface of the package to the PCB, instead of the conventional formed perimeter gull wing leads. The QFN-type package is known for its small size, cost-effectiveness and good production yields. QFN also possess certain mechanical advantages for high-speed circuits including improved co-planarity and heat dissipation. The QFN has pins on 4 edges of the bottom surface of the package. The QFN can have either a square or rectangle body as well as symmetric or asymmetric terminal patterns. The QFN was introduced to replace the gull wing lead Quad Flat Package (QFP) because the component leads are embedded in the plastic and cannot be bent during handling to insure consistent

PILLBOX ANTENNA DESIGN AND SIMULATION

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A pillbox antenna is a linearly polarized cylindrical reflector embedded between two Parallel plates. It is usually fed by a waveguide. The pillbox is part of a family of antennas called fan beam antennas which produce a wide beam in one plane and a narrow beam in the other. The pillbox antenna can be dual polarized and is also a relatively wide bandwidth antenna. The advantages of using a pillbox antenna for radar applications are It is easy to design and the cost of production is low. It is dually-polarized and it is also a wide band antenna. It has a high power handling capability The pillbox feed is traditionally located at the focal point of the reflector. For symmetrical antennas this is located in the middle of the aperture. Either a pin or waveguide feed can be used, depending on the system requirements. Further variations of these feeds can be found through the use of stubs which are used to obtain better impedance matching and reflector illumination, not discussed

RFID Tag and Reader Antenna Design Techniques

RFID stands for Radio-Frequency Identification. The RFID device provides a unique identifier for that object and just as a bar code or magnetic strip the RFID device must be scanned to retrieve the identifying information. More Detail: Microstrip and Printed Antenna Design

Looking For A Way To Ensure High Signal Quality... | Keysight Community

Looking For A Way To Ensure High Signal Quality... | Keysight Community

Helical (Helix) Antenna Design

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The helix antenna is a travelling wave antenna, which means the current travels along the antenna and the phase varies continuously. Helix antennas (also commonly called helical antennas) invented by John Kraus give a circular polarized wave.  Helix antennas are referred to as axial-mode helical antennas. The benefits of this helix antenna are it has a wide bandwidth, is easily constructed, has real input impedance, and can produce circularly polarized fields. There are two mode of circular polarization in helix antenna. Left handed helix antenna:  In left handed helix antenna if you curl left hand fingers around the helix, thumb would point up. The waves emitted from this helix antenna are Left Hand Circularly Polarized. Right handed helix antenna:  In right handed helix antenna if you curl right hand fingers around the helix, thumb would point up. The waves emitted from this helix antenna are Right Hand Circularly Polarized The minimum number of turns for a helix is between 3

Signal Integrity Analysis of USB 3.0 Data Bus

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USB ( Universal Serial Bus ) is the most popular connection used to connect a computer to devices such as digital cameras, printers, scanners, and external hard drives.  USB  is a cross-platform technology that is supported by most of the major operating systems. UART is a computer hardware device that translates data between parallel and serial forms ( SerDes ). A dual UART (Universal asynchronous receiver/transmitter), or  DUART , combines two UARTs into a single chip. The universal asynchronous receiver/transmitter (UART) takes bytes of data and transmits the individual bits in a sequential fashion. At the destination, a second UART re-assembles the bits into complete bytes. Each UART contains a shift register, which is the fundamental method of conversion between serial and parallel forms. Serial transmission of digital information (bits) through a single wire or other medium is less costly than parallel transmission through multiple wires. Below is USB 3.0 onboard interconnect

Printed Conformal Antenna Design

In many applications pertaining to missile, satellite, spacecraft and aircraft a directive antenna mounted on a curved body is required. Conforming the antenna to the surface save space and is often essential for structural reasons.  An antenna that conforms to a surface whose shape is determined by considerations other than electromagnetic; for example, aerodynamic or hydrodynamic called conformal Antenna.  Microstrip antenna technology is most suitable for conformal applications because of their ability to conform to non-planar structures. Microstrip antenna patches are placed above what may be characterized as a conducting plane with a dielectric substrate separating the patch from the conducting plane .  The properties of such an array depend strongly on whether it is small compared to the radius of curvature of the mounting body, in which case it behaves nearly like a planner array or whether it is comparable or large to the radius. More Detail: Microstrip and Printed A

Time Domain Reflectometry (TDR) Analysis of Transmission Lines

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T ime Domain Reflectometry is the analysis of a conductor lines (interconnects)by sending a pulsed signal into the conductor, and then examining the reflection of that pulse. A TDR transmits a short rise time pulse along the conductor. If the conductor is of a uniform impedance and is properly terminated, the entire transmitted pulse will be absorbed in the far-end termination and no signal will be reflected toward the TDR. Any impedance discontinuities will cause some of the incident signal to be sent back towards the source. By examining the polarity, amplitude, frequencies and other electrical signatures of all reflections; tampering or interconnect discontinuity may be precisely located Time Domain Reflectometry is the analysis of a conductor lines (interconnects) by sending a pulsed signal into the conductor, and then examining the reflection of that pulse. A TDR transmits a short rise time pulse along the conductor. If the conductor is of a uniform impedance and is