The Balun and The UNUN - Phil Storr`s home page
... equal and opposite flowing currents on the inside of their shields and their centre conductors. Current direction and current ratio between the centre conductor and inside of the shield in a non-radiating coaxial line is no different than currents in each conductor of a perfectly balanced ladder lin ...
... equal and opposite flowing currents on the inside of their shields and their centre conductors. Current direction and current ratio between the centre conductor and inside of the shield in a non-radiating coaxial line is no different than currents in each conductor of a perfectly balanced ladder lin ...
MFJ-259B HF/VHF SWR Analyzer
... Broadband detectors are sensitive to out-of-band external voltages, and solutions to most out-of-band interference are not simple. Common low-pass or band-pass filters behave like transmission lines of varying impedances on different frequencies. Low-pass or high-pass filters change impedance and SW ...
... Broadband detectors are sensitive to out-of-band external voltages, and solutions to most out-of-band interference are not simple. Common low-pass or band-pass filters behave like transmission lines of varying impedances on different frequencies. Low-pass or high-pass filters change impedance and SW ...
Some Aspects of the Balun Problem
... quads. Unless a gamma match or other type of unbalanced input-matching scheme is used, all beam antennas with balanced input terminals require a balun if the optimum performance of the antenna system is to be achieved when fed with coaxial cable. For example, when a balun is not employed, the feed l ...
... quads. Unless a gamma match or other type of unbalanced input-matching scheme is used, all beam antennas with balanced input terminals require a balun if the optimum performance of the antenna system is to be achieved when fed with coaxial cable. For example, when a balun is not employed, the feed l ...
Review of ITU-R activities/RNSS issues
... emissions in the band 1 164-1 215 MHz, whether space-to-Earth or space-to-space RNSS. While Resolution 605 requests study of RNSS (space-to Earth), the provisional aggregate pfd limit in footnote S5.328A is not limited to any specific direction. Received signal powers are typically calculated by lin ...
... emissions in the band 1 164-1 215 MHz, whether space-to-Earth or space-to-space RNSS. While Resolution 605 requests study of RNSS (space-to Earth), the provisional aggregate pfd limit in footnote S5.328A is not limited to any specific direction. Received signal powers are typically calculated by lin ...
Power Suppply and UART Circuit
... By default, C304 and C305 are not mounted, R301 is 0R. A 10R resistor (R302) is needed between VCC_RF and V_ANT to supply ...
... By default, C304 and C305 are not mounted, R301 is 0R. A 10R resistor (R302) is needed between VCC_RF and V_ANT to supply ...
Directional Virtual Carrier Sensing for Directional Antennas in
... of RTS and CTS, but also studied several other aspects of directional communication including power control and neighbor discovery in MANETs. All these previous studies discuss only the transmitter side beamforming, while directional antennas can be used for both transmitting and receiving. In many ...
... of RTS and CTS, but also studied several other aspects of directional communication including power control and neighbor discovery in MANETs. All these previous studies discuss only the transmitter side beamforming, while directional antennas can be used for both transmitting and receiving. In many ...
Dimensional and Electrical Considerations
... effects. Additional measurements can be used to find the actual ac resistance, including proximity effects, at a given frequency. The signal generator is again isolated with a very high resistance to minimize loading and artificially lowering the circuit Q. In these measurements, external capacitors ...
... effects. Additional measurements can be used to find the actual ac resistance, including proximity effects, at a given frequency. The signal generator is again isolated with a very high resistance to minimize loading and artificially lowering the circuit Q. In these measurements, external capacitors ...
SUBELEMENT G1 -- COMMISSION`S RULES [6 Exam
... A. The minimum power necessary to carry out the desired communications, with a maximum of 200 watts PEP output B. The minimum power necessary to carry out the desired communications, with a maximum of 1000 watts PEP output C. The minimum power necessary to carry out the desired communications, with ...
... A. The minimum power necessary to carry out the desired communications, with a maximum of 200 watts PEP output B. The minimum power necessary to carry out the desired communications, with a maximum of 1000 watts PEP output C. The minimum power necessary to carry out the desired communications, with ...
AT-897 - Funktechnik Dathe
... When the impedance of the antenna is different from that of the transmitter and transmission line, a “mismatch” is said to exist. In this case, some of the RF energy from the transmitter is reflected from the antenna back down the transmission line, and into the transmitter. If this reflected energy ...
... When the impedance of the antenna is different from that of the transmitter and transmission line, a “mismatch” is said to exist. In this case, some of the RF energy from the transmitter is reflected from the antenna back down the transmission line, and into the transmitter. If this reflected energy ...
High-Frequency RFID Tags: An Analytical and Numerical Approach
... EMC engineer with a means of approximating the interference potential of RFID systems. Referring to Figure 1 the expression for the scattered field is determined by writing the open circuit voltage (Voc ) developed on the tag antenna in terms of a sinusoidal current induced on the antenna. The relat ...
... EMC engineer with a means of approximating the interference potential of RFID systems. Referring to Figure 1 the expression for the scattered field is determined by writing the open circuit voltage (Voc ) developed on the tag antenna in terms of a sinusoidal current induced on the antenna. The relat ...
Antenna Theory - The Free Information Society
... voltage is induced into the antenna, which serves as a conductor. The induced RF voltages are then used to recover the transmitted RF information. 2. Current and voltage distribution. a. A current flowing in a wire of a length related to the RF produces an electromagnetic field. This field radiates ...
... voltage is induced into the antenna, which serves as a conductor. The induced RF voltages are then used to recover the transmitted RF information. 2. Current and voltage distribution. a. A current flowing in a wire of a length related to the RF produces an electromagnetic field. This field radiates ...
IOSR Journal of Electronics and Communication Engineering (IOSR-JECE)
... Enoch et al. has used metamaterial as substrate [24] and has showed how the characteristics of metamaterial can change the emission of an embedded source. The layers of copper grids seperated by foam were used as metamaterial. This metamaterial possessed the plasma frequency at about 14.5 GHz. It ha ...
... Enoch et al. has used metamaterial as substrate [24] and has showed how the characteristics of metamaterial can change the emission of an embedded source. The layers of copper grids seperated by foam were used as metamaterial. This metamaterial possessed the plasma frequency at about 14.5 GHz. It ha ...
Simulation and Design of a Very Small Magnetic Core Loop
... field strength (E) at the receiving position by using a standard loop antenna for EMC; 2) measure the received voltage (Vo ) of MCLA at the same receiving positions where the standard loop antenna was located; 3) derive the antenna factor from Eq. (7). When the receiving electric field strength was ...
... field strength (E) at the receiving position by using a standard loop antenna for EMC; 2) measure the received voltage (Vo ) of MCLA at the same receiving positions where the standard loop antenna was located; 3) derive the antenna factor from Eq. (7). When the receiving electric field strength was ...
The Dipole
... between the ‘feed’ line and ‘free space’. For any antenna to launch a signal, the field must be made to ‘fringe’ from the feed line into the space around the antenna. Considering how the field associated with the feed behaves at the dipole will show that as charges move on the surface, the field fri ...
... between the ‘feed’ line and ‘free space’. For any antenna to launch a signal, the field must be made to ‘fringe’ from the feed line into the space around the antenna. Considering how the field associated with the feed behaves at the dipole will show that as charges move on the surface, the field fri ...
Enhanced Bandwidth Artificial Magnetic Ground Plane for Low
... only 13–16 GHz. The achieved bandwidth for the designed lowprofile antenna is even wider than the in-phase reflection bandwidth of the EBG. The 1 GHz upward shift in the bandwidth of the antenna is attributed to the near field interaction between the antenna and the EBG. A similar shift was observed ...
... only 13–16 GHz. The achieved bandwidth for the designed lowprofile antenna is even wider than the in-phase reflection bandwidth of the EBG. The 1 GHz upward shift in the bandwidth of the antenna is attributed to the near field interaction between the antenna and the EBG. A similar shift was observed ...
Polarization Antenna polarization Cross polarization
... two orthogonal. This may be due to the arrangement of power input leads to various points on a flat antenna, or due to an interaction of active elements in an array, or many other reasons. The geometric figure traced by the sum of the electric field vectors over time is, in general, an ellipse as sh ...
... two orthogonal. This may be due to the arrangement of power input leads to various points on a flat antenna, or due to an interaction of active elements in an array, or many other reasons. The geometric figure traced by the sum of the electric field vectors over time is, in general, an ellipse as sh ...
Equivalent Circuit of Repeater Antenna for - Hori
... of wireless power transfer systems. In particular, electromagnetic resonant coupling is a promising technology for wireless power transfer because power can be transferred over a large air gap; this method is more practical and efficient than the conventional methods. This technology has been propos ...
... of wireless power transfer systems. In particular, electromagnetic resonant coupling is a promising technology for wireless power transfer because power can be transferred over a large air gap; this method is more practical and efficient than the conventional methods. This technology has been propos ...
Analysis of Five Different Dielectric Substrates on
... Triangular Patch, X-band, Radiation Characteristics. ...
... Triangular Patch, X-band, Radiation Characteristics. ...
Development of large area rf ion sources for fusion applications
... When the source is operated as a negative ion source, with a supercusp magnet configuration and using the twoturn antenna (for enhanced power coupling), the electron temperature is reduced to 1.5-2 eV across the whole of the extraction plane. This is expected due to greater confinement of the electr ...
... When the source is operated as a negative ion source, with a supercusp magnet configuration and using the twoturn antenna (for enhanced power coupling), the electron temperature is reduced to 1.5-2 eV across the whole of the extraction plane. This is expected due to greater confinement of the electr ...
Antenna (radio)
An antenna (plural antennae or antennas), or aerial, is an electrical device which converts electric power into radio waves, and vice versa. It is usually used with a radio transmitter or radio receiver. In transmission, a radio transmitter supplies an electric current oscillating at radio frequency (i.e. a high frequency alternating current (AC)) to the antenna's terminals, and the antenna radiates the energy from the current as electromagnetic waves (radio waves). In reception, an antenna intercepts some of the power of an electromagnetic wave in order to produce a tiny voltage at its terminals, that is applied to a receiver to be amplified.Antennas are essential components of all equipment that uses radio. They are used in systems such as radio broadcasting, broadcast television, two-way radio, communications receivers, radar, cell phones, and satellite communications, as well as other devices such as garage door openers, wireless microphones, Bluetooth-enabled devices, wireless computer networks, baby monitors, and RFID tags on merchandise.Typically an antenna consists of an arrangement of metallic conductors (elements), electrically connected (often through a transmission line) to the receiver or transmitter. An oscillating current of electrons forced through the antenna by a transmitter will create an oscillating magnetic field around the antenna elements, while the charge of the electrons also creates an oscillating electric field along the elements. These time-varying fields radiate away from the antenna into space as a moving transverse electromagnetic field wave. Conversely, during reception, the oscillating electric and magnetic fields of an incoming radio wave exert force on the electrons in the antenna elements, causing them to move back and forth, creating oscillating currents in the antenna.Antennas can be designed to transmit and receive radio waves in all horizontal directions equally (omnidirectional antennas), or preferentially in a particular direction (directional or high gain antennas). In the latter case, an antenna may also include additional elements or surfaces with no electrical connection to the transmitter or receiver, such as parasitic elements, parabolic reflectors or horns, which serve to direct the radio waves into a beam or other desired radiation pattern.The first antennas were built in 1888 by German physicist Heinrich Hertz in his pioneering experiments to prove the existence of electromagnetic waves predicted by the theory of James Clerk Maxwell. Hertz placed dipole antennas at the focal point of parabolic reflectors for both transmitting and receiving. He published his work in Annalen der Physik und Chemie (vol. 36, 1889).