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# Antenna Polar Plot

1000 Threads found on edaboard.com: Antenna Polar Plot

## How can I measure the Side-Band Amplitude?

Hello Everyone, I have a NFC system (Reader -> Power Amplifier -> antenna <-> NFC Tag) in which I can generate a H-field strength from 1.5 A/m to 7.5 A/m. So I would like to know how I can measure the Side-Band Amplitude (SBA) as well as lower sideband (@lsb) and upper sideband (@usb) of the system. Many thanks in

## "Current adds up in phase"

what do we mean when we say "current adds up in phase"? For a wire antenna, there's already a current arises from feed source and it causes antenna to radiate, then why we emphasize 'adds up in phase'. It sounds like we use a second source to increase the radiation. Doesn't it?

## Method of Moment- S11, Gain and Directivity of dipole antenna

Dear, i will be grateful if anyone can send me the matlab code for using Method of Moment technique to find out s11, directivity and gain of dipole antenna. Thanx

## A new group for antenna RESEARCH on

I recently set up a group The group was set up to provide a forum for discussion of moderately advanced to advanced antenna research. Typically this will mean from undergraduate research projects in universities to more advanced topics. Here's a Wiki

## Antenna Setup in different configuration

Hello, I am trying a 2 cases setup like this where there will be 2 horn antenna facing each other and S parameter data will be extracted. For the 2nd case using the similar setup there will be a large metal plate in the middle of the line of sight of horn antenna. I should expect antenna with metal plate, the S parameter value should (...)

## H field measurements with waveguide twist

I am trying to get the value of the h field with a horn antenna as a reference antenna. I used a 90 degrees waveguide twist with the horn antenna in preset to measure le level of the received signal. But I am getting strange values. Am I proceeding the right way to measure the h field? If yes is it a scaling issue if the values that I?ve (...)

## difficulty in matching off the shelf GPS antenna

Hi , I encounter this difficulty when matching my off the shelf GPS antenna to 50 ohm. hope someone could tell me whats when wrong and how to debug. so the original load impedance was shown in the pic below. i have a "series-shunt-series-shunt" matching circuit before my GPS antenna. series component was replaced with 0 ohm and below are th

## Multi-loop antenna selector

Hi I want to combine 8 loop antennas into one structure, each of them at a different angle to the others. By using 8 relays, I want to select each of these 8 loops so that I can null a signal at a wanted direction. So instead of using a single loop and a rotor, to use multiple loops and select each of them. Now the problem I have is that I have on

## Characteristic impedance of combination of CPWG and stripline on inner layers

Hi everyone, I have been searching for quite a while about the following subject, but canīt seem to find a decent answer on this. Imagine a 4-layer PCB (Top layer, Mid1 layer, Mid2 layer, Bottom layer). Mid1 layer and Bottom layer are GND panes with here and there vias to pass signals from the top layer to the Mid2 layer and back. RF signals on

## Spurious radiation and surface waves in MSP Antenna

I read some articles in which spurious radiation described as the parasite radiation harmonic frequencies caused. Some other say it happens because of nonlinear devices in antenna. Can we say non-linearity cause to harmonics and so to spurious radiation? And can we say all of those which are spurious, parasite radiations occurs because of surface w

## Slotted Waveguide Antenna

Slotted waveguide antennas can often be very useful. The basic idea is that in moving the slots around the amplitude and phase distribution of an array can be controlled. The trick is finding the appropriate placement and then figuring out how to manufacture the thing. Modern simulation tools and numeric controlled machining makes these much eas

## Heterodyne detection, non-linear mixer and minimum detectable signal (2-way radar)

I've been working on a transceiver system with BGT24LTR11 chips at it's core and I was unable to achieve necessary signal to noise ratio. I want to know whether it's theoretically possible and for that I need to understand how the terms in the title all intertwined. The following parameters/figure of merit I'm familiar with: Minimum detectable

## Which Antenna for VHF/UHF ?

As P.Gibson mentioned on his Vivaldi Aerial patent, this type of antenna has good performances in 2GHz-40GHz frequency range. In a Vivaldi antenna, the slotline to free space transition is given by exponentially flared slotline. In order to get efficient radiation in free space, the width of the open end should be greater than λo/2. At 240MH

## Is it stable that phase drop to close to 0 but rise to 75 degree when gain is 0dB?

The phase margin is 72 degree when the gain is 0dB. However, the phase margin is close to 0 before the frequency reaches the unity-gain bandwidth. Is the op-amp stable? Why? Thank you. 157193

## Directivity of Radar Sensor HFS-DC06H

I have tested the directivity of 5.8GHz HFS-DC06H radar sensor and found it to be 360 degrees, although I was expecting it to be 180 degrees because of the back metal shield on the antenna PCB. See the attached images for the sensor and radiation pattern from some Chinese website. I want to have the directivity of 180 degrees instead of 360 degr

## Safe value of Vgs in sub-threshold design (4.5nUT < Vgs - Vth < -2nUT)?

Hello, I am designing circuit (using 0.18um). Usually, by biasing Vgs < Vthreshold of MOSFET, we can push MOS into sub-threshold region. My curious question is: How much value of Vgs is "good" as a "rule of thumb"? I have referenced to "Trade-offs and optimization in Analog CMOS design" book, and they supplied a good reference (please check t

## Question about Beam forming and MIMO

Hi, From the view of antenna theory, beam forming means using multiple antennas to create a desired beam, or controlling the beam direction by changing the magnitude and phase of each antenna element. Usually we'll regard all the elements as one antenna when we look at the far field. In communication theory, MIMO means (...)

## PI compensator implementation in microcontroller and calculation for that

Hi, I used a microcontroller dsPIC33FJ16GS504 for on grid microinverter. In compensator design circuit (attached) current compensator block I want to implement in microcontroller in which PI compensator is used as per the document (for details are available in microchip document AN1444). I know basic about the PI controller but how to implement in

## Gain, Sensitivity and Range

what does the rule you want to apply in your system ? This document offer 2 methods for choosing pre-amp: prioritize sensitivity or dynamic range. If your receiver near transmitters, ( including noise from other transmitter) the signal input too strong, it can make your receiver saturation and total gain would be decrease. You must chose pre-amp w

## switching Voltage amplifier into transcondactance amplifier

Hello I Have designed a Voltage amplifier ,i Have a high impedance on the input and low impedance on the out put. amplifier plot and its Gain responce shown bellow. if the schematics bellow there is a transimpednce amplifier design. How make our built amplifer to sense current?(as shown in the plt bellow? Thanks 156992