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1000 Threads found on Wavelength 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
Hello and thank you in advance for any advice I've built a few Wifi antennas in hopes of drawing in a signal from a few dozen meters away. I've had trouble figuring out how to translate the output from the antenna's SMA connector to my computer. I tried a cheap USB dongle, but it doesn't play well with linux (also didn't work on my windows dri
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
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?
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
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 (...)
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 (...)
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
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
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
Hello, I see that slotted waveguide antennas are usually built from elements with diagonal offset (as shown in attached figure). The longitudinal offset is understood to me (phase difference), however the horizontal offset is not clear. If the waveguide is excited by TE 10 fundamental mode, the E field keeps his sign along X axis. Can you
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
What do you think of use Microstrip Patch antenna for 240-320 MHz? I knew it's rarely designed for this bandwidth.
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
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 (...)
Hello Klaus, Thanks for your response to my post. I want to achieve about 10Gbps at a distance of 10m. I intend to transmit via a laser diode with an optical power of 30mW and a wavelength of 405nm. I need examples of transmitter and receiver circuit designs that can achieve this. Looking forward to hearing from you
Hi, following statement is taken from a document of Keysight spectrum analyzer: Finding a preamplifier that will give us better sensitivity without costing us measurement range dictates that we must meet the second of the above criteria; that is, the sum of its gain and noise figure must be at least 10dB less than the noise figure of t
Where can I buy a budget RF meter (1-5GHz), and which brand is good for that? I need it for verifying my experimental setup for radio tomography and require to read WiFi signals.
Hi Everyone, I have designed a NFC system in which I can have around 100 V on the input antenna. So I need to attenuate the antenna signals (in terms of mV) before feeding them back to the reader module as well as keeping the antenna's resonance circuit quality factor. Hence, I would like to know an attenuating buffer circuit for my (...)
can anyone provide any design reference or method to achieve a 23 dBi gain at 2.4 GHz? thanks in advance