| Line-Reflect-Reflect
Technique |
Definition
LRR- LINE REFLECT REFLECT is a new self-calibration procedure for the calibration
of vector network analyzers (VNA). VNA measure the complex transmission and reflection
characteristics of microwave devices. The analyzers have to be calibrated in order
to eliminate systematic errors from the measurement results. The
LRR calibration circuits consist of partly unknown standards, where L symbolizes
a line element and R represents a symmetrical reflection standard. The calibration
circuits are all of equal mechanical length. The obstacle, a symmetrical-reciprocal
network is placed at three consecutive positions. The network consists of reflections,
which might show a transmission. The calibration structures can be realized very
easily as etched structures in microstrip technology.
During the calibration [G], [H], which represents the systematic errors of the
VNA is eliminated in order to determine the unknown line and obstacle parameters. MICROWAVE
DEVICES
Microwave devices are devices operating with a signal frequency
range of 1-300GHz. A microwave circuit ordinarily consists of several microwave
devices connected in some way to achieve the desired transmission of a microwave
signal. The various microwave solid state
devices are, * Tunnel diodes
These
are also known as Esaki diodes. It is a specially made PN junction device which
exhibits negative resistance over part of the forward bias characteristic. Both
the P and the N regions are heavily doped. The tunneling effect is a majority
carrier effect and is very fast. It is useful for oscillation and amplification
purposes. Because of the thin junction and shot transit time, it is useful for
microwave applications in fast switching circuits. *
Transferred electron devices
These are all two terminal negative resistance
solid state devices which has no PN junction. Gunn diode is one of the transferred
electron devices and which works with the principle that there will be periodic
fluctuations in the current passing through an n-type GaAs substrate when the
applied voltage increases a critical value i.e. 2-4Kv/cm.
You may also like this : Quantum Dot Lasers, Plasma Antennas, Organic Light Emitting Diode, Narrow Band & Broad Band ISDN, Nanotechnology, Led Wireless, Laser Communication Systems, Josephson Junction, Introduction to the Internet Protocols, Imagine , Cellular Communications , Heliodisplay, Optical Mouse , Time Division Multiple Access , Element Management System, Extended Markup Language , Synchronous Optical Network, Dig Water , CRT Display , Satellite Radio TV System, Robotics , Wireless Application Protocol , Synchronous Optical Networking , Cellular Radio , Optic Fibre Cable, Infinite Dimensional Vector Space , Low Voltage Differential Signal, Plasma Display , GPRS,Landmine Detection Using Impulse Ground Penetrating Radar, NRAM, GSM , Wireless Intelligent Network , Integrated Voice and Data , MEMS, Smart Quill, Automatic Number Plate Recognition, Optical Camouflage, Smart Fabrics, Java Ring, Internet Protocol Television, FireWire, Night Vision Technology, RD RAM , Implementation Of Zoom FFT in Ultrasonic Blood Flow Analysis, Military Radars , Modern Irrigation System Towards Fuzzy, Smart Cameras in Embedded Systems, Spin Valve Transistor , Moletronics- an invisible technology,Electronics Seminar Reports, PPT and PDF.
|
<<back |
