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482 Threads found on Antenna Circuit
Hi, Our tpms based project need to add NFC circuit to wake up Microcontroller (CC2541). We are using Premo antenna for NFC. Output of antenna passes through 137217 this circuit. So far we could able to wake up uC in max.2cm distance. We have to improve this distance.
Are you saying that through this spiral does an electric current pass (ie the wiring is part of some circuit consuming power), or is it just a helical-like antenna ? If you want a 'stable' 50Hz noise source, I would recommend to make some circuit that you could predict the electromagnetic flow and even tune it. An open (...)
Hi this is an experimental regenerative detector that I am making. The original circuit used an RF premaplifier between the antenna and the detector, which I would like to remove (to eliminate IMD products) and see how the circuit will perform. I am aware of the antenna capacitance changing and isolation issues, but I would (...)
Hi, I am planning on designing a GPS receiver board using U-Blox LEA-M8T. I will use an active patch antenna. I will design the board using EAGLE CAD and the board itself will be 4 layers. I have some questions hoping that I will get answers. 1. Do I need an additional LNA on the circuit for this configuration? 2. Is there any tips on de
Hi All, just bought a non working antenna Analyzer model FG-01, (made by YOUKITS) & after opening found out that the IC4 is missing see attached photo. If anybody can help me in identifying this IC & the source to buy the same Thanks in advance.
I am doing UG Final Year Project in antenna.Our antenna is metamaterial Triangular Split Ring Resonator(TSRR) and I am in need of length and width equations for TSRR.I searched a lot but I can't find the equation.Can anyone tell me if there is any equation or any other alternative way(circuit model to layout model) to find the equation?
Hello all , I want to use some flexible substrate for my antenna design as well as for circuit design at 900 MHz or higher range of frequency, can anybody help me please , that what substrate i can purchase. which are commercially available. Thnx in advance
Because in the real life at high frequencies there are no ideal transmission lines, the microstrip TL that feeds the antenna SHOULD be part of the antenna impedance match. I mean, you design the circuit PCB layout, draw the microstrip line that feeds the antenna (with whatever length), and AFTER that design/tune the (...)
Hi , Guys I have UHF FM Transmitter with power about 5W I want it to send video signal through AM the carrier frequency here the important section of schematic : 135260 I tried to inject signal in Q407 emitter ( i think this make low level AM ) after remove R408 the picture shows up in my TV with lot of noise and
Falstad's simulator is free, animated and interactive. By reducing the timestep you can use frequencies in the GHz. Its antenna model provides three simultaneous broadcasts on AM frequencies, which you can tune a detector to pick up individually. LTSpice is free and more sophisticated than Falstad's. It contains models o
An equivalent-circuit model for the patch antenna can be found in Balanis' "antenna Theory: Analysis and Design" textbook, and probably elsewhere on the internet. Basically, you want to create a lossy, half-wavelength resonator, the characteristic impedance of which differs significantly from your system impedance.
I think the diagram you show is quite primitive. The antenna will influence the transmitted frequency. It would be better to use a buffer transistor at the output of the oscillator (repeater on emitter maybe). I don't think you need to change from bipolar to FET. The TV spectrum is very large, from 48 MHz to over 800 MHz. What channel do you want t
What does physically happen when a receiver antenna in Open circuit/ and short circuit mode is exposed to RF signal? Is the power reflected back?
Hi, I would like your reviews on this circuit The author states advantages over mosfets and he uses tubes.
Yes, you see almost real impedance of an antenna at it's center frequency, e.g. a dipole with length of lambda/2. An antenna is a distributed device, it has no physical L or C. In so far the quoted |Z| equation (not valid for Z) describes only a possible antenna equivalent circuit in a limited frequency range, not an (...)
i am designing a cavity backed bowtie antenna.what is the need for cavity in antenna designing.if i am using a cavity box ,should i have to use a groundplane .how to calculate the dimensions of the cavity box.what material should be assigned to the cavity box.
1/2 wavelength unterminated? is this what you want? why? Normally antenna are tested with return loss.
I am working on a pattern reconfigurable antenna and for this i need to bias the PIN diode from a battery through bias line. For this I need a RF choke inductance to isolate the ac from the bias line. I have seen different value of inductor is being used by different author. Is there any specific formula to select the RF choke to select for frequne
Hi, I need to design a circuit that will provide power to a TV antenna amplifier. My constraints are : * Characteristic impedance : 75 Ohm, * Power supply for antenna amplifier : 24V @ 100mA and * Available power supply : 9V @ 1.6A I think I will base the solution on a step-up converter. But I have a concern about the harmonics of (...)
Hello everyone how are you. I am working on a circuit that has a SIM800 module with an external L Shape antena. The module is powered by a LM2596 DC DC converter. The problem that I have is during the module registering phase to the network. It suddenly resets and start o ver again. But if I hold the antenna with my hand or if I place a finger ove
Hi, I have a tiny electronic circuit (RF active antenna with fitted SMA connectors) and I want to enclose it in molten plastic or other resign, so that I can create a short of "rubber duck" antenna. The major concern is the SMA connector, which is fitted in molten plastic in commercial rubber duck antennas. This allows the (...)
Hello, We are designing a 20W SMPS which simply supplies 15V at 1A to an RF Phased array antenna circuit. (its for comms). Vin = 48V. We were wondering if it is overly extravagant to do this as an Half-Bridge LLC converter? Its just that the SMPS will be very close to the Comms signal processors and other sensitive circuitry, so we (...)
The answer to your question: Why do we use a short circuit line to the ground plane? is: For proper impedance matching. IFA is a variant of ILA (Inverted L antenna) which has an L shape and don't use this short transmission line for "proper" impedance matching as IFA. ILA gets the right port impedance changing the length and the shape above the g
I'm not acquainted with CST, but in HFSS you cannot do that (as far as I know). You need to fit the equivalent circuits from the Microstrip antennas chapter in Balanis book (probably two RLC tanks regarding the two radiating edges) and then tune it using for example ADS, until it fits the resonances obtained in CST or HFSS.
Thank Pjdd, I do not have the modules yet (also i do not have VHF/UHF detectors etc), that is why I am thinking should I order them or not. I would like to extend range up to 1-2 km with help of antenna amplifier. There are 2km range modules on ebay too, but they are about 20 times more expensive. these things
So it is not just an antenna, it is energy saving LED power supply circuit. L1 is an antenna to pick up energy from 5.8 GHz radio sources. Efficiency of this antenna will be maximized when it is resonant at operating frequency. Also it's aperture should be maximized. How do you know it is specifically designed for 5.8GHz? (...)
As analog engineer, I have been asked to review a design before production. This design include an antenna on the PCB (see attached picture, about 5cm by 5cm), but the antenna design seems very strange to me. This emitter antenna must work in the band of few Hz to few 10 Hz (ELF band). A simple calculus tells me that the wavelength is (...)
Im designing a lightning protection circuit for GPS module that works off 3,3V and antenna line is used to feed antenna with 9V DC through bias tee. I have a gass tube discharge(GDT) element in antenna cable that should take the voltage down to about 90V, but I need help designing the low voltage protection stage that I (...)
for that shield to work, there has to be a "ground plane" somewhere inside of the PC board. you connect that metal shield to the ground plane in numerous places and try to make a faraday cage. unfortunately, since you need an antenna external to the are going to be deliberately screwing up the faraday cage, and may need to add a low
The circuit is not an amplifier, and is just a common base Colpitts oscillator with an antenna attached at the output. C5 is the feedback capacitor, and C3 is the base decoupling capacitor. C3 has low reactance at oscillation frequency (RF), and high reactance at modulation frequency (AF). This is a poor design, and if you touch the antenna, (...)
The difference is: 1- antenna is on the top the layer while EBG at the bottomof the layer 2- two layer, first layer for coplanar antenna and the second layer on the top EBG and the bottom full ground. then this two layer attached togather with spacing to avoid short circuit. The EBGs will have different behaviors.
In the project manager look for the reflector antenna icon ...... make sure you have set up a far field sphere to calculate radiation patterns in the first place. that plus the information above.
you have an antenna that is well matched at EVERY frequency but one. quick, patent it
Hello, I have designed a circuit for data transfer using Bluetooth Low Energy for a flexible substrate with thickness 125um. I need a help in searching a suitable 2.4GHz antenna and requirements for the same. Thank you in advance.
Hello everyone ! I would like to model my patch antenna under its equivalent circuit form, but I don't know how to combine the already existing model of a loop antenna with my model which include a partial ground plane and a microstrip feed line. I will be grateful if you could help me or give me some recommendations of useful (...)
If your antenna had a built in resistor to ground, say 10k, it would be simple to have a 1~10M pullup and Cap for low current to activate a P-ch MOSFET high side switch to de-activate the circuit, then activate when antenna 10K to ground without degrading the RF. PC's use the same method to detect a speaker connected (<100 Ohm) and video (...)
Go only with the printed antenna. The worse printed inverted-F would work better than any chip antenna. The only thing that an inverted-F antenna needs to work well, is a good ground plane (which can be the metal shield of your circuit) and spend little time on tuning.
it is a mixer. It is probably a homodyne radar receiver of some sort. It sends out RF from a transmit antenna. Simultaneously, it sends a copy to one port of this "mixer" called the "local oscillator port". When the return bounces back from the ground, it is received by an antenna and input to the "RF Port" of the mixer. The resultant is a low
Hi Every one This is kico from shenzhen XCE company. We are a manufacturer of printed circuit board over than 10 years in shenzhen,china. Our products include microwave sensor&source circuit board/RF synthesizer circuit board/Satellite transceiver circuit board RF transceiver&Transmitter circuit (...)
I am doing circuit soldering but how I know which antenna speed is required and which software needed for Nokia 6600 mobile repair need diagram also and repair tips .Thanks
More information needed. I guess your "antenna" is a RFID reader coil. To extent the range, the coil current must be increased. Reducing the coil resistance should basically work in this direction, but the effect depends on the transmitter circuit.
2SC4367 has a typical transit frequency of 1 GHz (min. 600 MHz), so you're lucky if the circuit is oscillating at 900 MHz at all. You all want to use transistor with GHz bandwidth instead. Apart from this point, what's the value of C2? Is your circuit layout suited for 900 MHz at all? If you connected an antenna, it's frequency (...)
Most important aspect is the antenna coupling factor ( transformer coupling) THe gap between sender and receiver must be smaller than the loop antenna for reasonable coupling. THerefore tune each coil ( round or square) to resonate more maximum Q with a large diameter > gap. ( just like RFID's in store exits) This can be extended with high mu
So you just need to do Q spoiling? How fast does the coil energy need to ring down? I'm guessing that you're seeing inconsistent behavior because the switching isn't synchronous with the phase of the antenna current. Ideally you would switch on exactly when the coil current is at zero, but that means the capacitor voltage will be at its maximum, s
Hello Everyone... I have made antenna and tuning network which can detect MiFare and HiD iClass cards. i.e. 13.56Mhz... So for that i need to control unwanted harmonics of 13.56Mhz... I have designed antenna tuning circuit as per MiFare suggest. Card detection range in around 4 cm. So how can I reduce effect of harmonics??? And what (...)
Can you help me and take a look at this amplifiers? They are supposed to be antenna preamplifiers. On the left side is my calculated FET amplifier. On the right side the drain resistor is replaced with LC circuit that resonates on 14MHz. Yes I know, the input is 14.25MHz. I calculated it by mistake for 14MHz, but it's not important. The input signa
What is a better approach to harvest some radiated field from barbed wire parallel to an overhead high power transmission line ? : -A bridge rectifier at one end of a barbed wire against a grounded rod, or -A 60Hz LC tuned circuit from the barbed wire serving as antenna against a grounded rod. (plus rectification) -Or other ? And why? Not i
Hi All. My want to add GSM Internal and external antenna switching in my project. I'll use GSM Module with Antenova A10340 Internal Chip antenna and External SMA antenna connector. I want to implement a circuit so user can choose either internal or external antenna option. Can anyone advise how to (...)
Good Day Dear Members, I have designed the following rectenna in CST Design studio that works in parallel with the antenna designed at 900 MHz using CST MWS.(Fig1) I have placed all the relevant Voltage sources and probes in the circuit as shown, but Im unable to generate correct DC Voltages and Current at the output of the circuit. (...)
how to find input impedance of patch antenna in ADS and how can i match it to 50ohm using microstrip line