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455 Threads found on Antenna Circuit
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.
Hello All, Please help me in plotting the gain in HFSS. I go through these steps: result/ far field report/rectangular plot /antenna params/ Peak gain or peak realized gain / and set solution in context to sweep and primary sweep to freq, and press new report, but the HFSS does not give me result. It keeps loading!! Please help. Kawther
Hello All, I drew an antenna as in one of the papers. I analysed it, and created the VSWR graph. It was as below 122628122629 A very high VSWR at the notch frequency. The VSWR in the paper was about 26. Why did i have a very high VSWR at the notch frequency? Regards, Kawther Hamad,
I think you can use PCB trace antennas. Inverted F-antenna, Meandered inverted f antenna etc.
I was thinking of the ideal and lossy transmission line models in circuit simulation programs, e.g. SPICE. It's important to understand if transmission line common mode waves are involved, if so a combination of multiple transmission line models may be used to model common mode and differential waves. What's the frequency range of your antenn
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
I understand that you have one model with two antennas, and each antenna is connected to a port. Now you want to simulates the interaction between the two antennas. First you get S21 from the 2-port simulation. Then, instead of creating two additional 1-port EM models (one with antenna 2 shorted, the other with (...)
Good Day Member, I am working on a rectenna that harvest GSM energy at 900 MHz and converts it into DC Voltage for charging a cell phone battery. From various literature review, I have made a simple patch antenna in CST MWS and designed its relevant rectifier circuit in ADS. The questions I want to ask are following: 1. In most of the rectenn
Is there any way to isolate the antenna ground from the rest of the circuit? I am using EMDS/ADS2009 for circuit simulation?
Hi everyone, I am working on RFID tag design and i want to choose the chip so i have chosen Alien higgs 4 , they mention in the datasheet the parallel capacitance input is equal to 0.89 PF and the resistance parallel input is 1800 K ohm but when i have read some papers they mention the Higgs 4 chips impedance is equal to (18-181j ) , so if anyon
Hi Again, I tried to find out how the last problem occurring and I see when I use small antenna this is happening much more and it depend to position of antenna too. So it seems it is RF effect on circuit. In the circuit there is polygon, is there any other ideas to decrease this effect ? BR,
hi, i must design multifunctional SRR-loaded printed monopole antenna. how can i add switches on SRR in HFSS? like this
Your transmitter is messy, I am surprised it works. Usually a 100MHz transmitter circuit is neat and tidy. The distance is increased when the antennas focus the radio beam. A Yagi antenna has good focussing.
That all looks good to me. You have the fixed regulators wired correctly. Watch out for the antenna connection on the module, at 5.7GHz the track width and spacing are critical if you want most output to reach the antenna. Brian.
With the EXPLOSION of 3d printing, has anyone come across a LOW COST way to fabricate microwave components for prototyping? I mean a method of making precision tolerance microstrip on FR4 or Duroid for maybe under $500? Or a way of making waveguide and antenna horn type components from sintered metals for maybe under $1000? It seems that
Hello guys! How are you? Well, I´m working with RFID from Texas Instruments. I am starting a new project that I want use 2 antennas for the same electronic. Can I use a mux between antenna and electronic? What are the parameters that I need look for make a best choice about mux? Tnx very much! PS: My RFID signal have 134.2KHz with
Dear guys, I want to estimate the effect of bondpad to my circuit's performance. I think the dominant effect is shunt parasitic capacitance. I used HFSS to simulate antenna, so I tried to simulate parasitic capacitance of bondpad but I don't know is my setting correct or not? When I extended the boundary, the result was changed! Thus how can I k
Hi I`m trying to add RFID to my project and due to constrained memory and cost I decided to use classic 125kHz RFID. Instead of building all the analog circuitry I use HTRC110 interfaced with PIC32. I calculated resonant frequency for both antennas ( 700uH and 13uF ) and tried them both in circuit implemented according to NXP's AN98080. (...)
Hello all. I don't have much training in transmission lines so my question is pretty general. I've been tasked with creating a coplanar antenna on top of a small silicon cantilever which will just be held in air, thus the need for a single plane design. The goal is to produce a large magnetic field at the tip of the cantilever and I was given a
The circuit will work in RF and is in use for many years especially in HF frequencies. For some examples search the net for: "XPhase - Interference reduction " The main problem of the system, like in any other multi-antenna systems, is that you need good antenna correlation (or isolation between antennas) which sometime is (...)
Another possible solution.. If you know the components' values and part numbers, you can build the same circuit on a seperate PCB and measure it standalone. Then measure the input impedance of the circuit at the antenna input after that extract the s-parameters of the first copied circuit from these second measured (...)
Dear all I have made mirostrip antenna with shorting circuit techniques to reduce the size of the antenna, but it produced very little bandwidth. so T replaced the shorting pin with 1 ohm chip resistor. when I simulate in software CST Microwave, Realized gain antenna is about-32dB. Why the value of this gain is negative? (...)
Hi tony, I use Series 2000 Micro Reader by Texas Instruments. link: When I said coil, I meant antenna, sorry for this. The Microreader need a 47uH antenna to work, and I did it, but now, I need use a antenna of 49 uH, for this I want use other passive components to ma
parts i have : antenna wire,magnetic wire,toroid core, 23 mhz crysrtal oscillator,some transistors ,resistors,capacitors.... i want to design circuit to simply on and off the led by radio waves. could u sugest me simple circuit with to do this.. plzz.thank you in adavance
I'm agree with biff44. There is another resonance coming from a different source rather than antenna. A patch antenna can not present such a very sharp S11.There should be another source like an open circuit or short or something else..
Design areactive L network in order to provide impedance matching between transmission line of Zo = 300 + j60 and an antenna having impedance of 80 +j100 at the frequency of 1MHz. How do design this circuit? My professor told me that while designing L impedance matching circuit we need to make the shunt arm parallel with the one with the (...)
Hello everyone Can anyone please help me designing a balun/transformer to match a receiver loop impedance of 4ohms to a value of 50ohms (coaxial cable). I have designed a multi-turn antenna. It is working in the range of 3-30khz. Please help.:?:
Can you show the load impedance curve? Maybe the problem is resonant load (e.g. antenna with insufficient bandwidth). In this case it's probably not possible to achieve a better matching. Too much delay between load and matching network can be a problem as well.
Hi all! I have to design a planar antenna and microwave power amplifier integrated on a "single substrate". My design frequency is 2.45 GHz. Which substrate would be better: Fr4 Epoxy (4.4) or Rogers RT Duroid 5880 (2.2) ?? Your kind help is highly regarded. :)
Hello Forum, This is my first post here. I looking for help with Designing the antenna feed circuit for my GSM Unit. I want make GSM 2G+ mobile phone. I use Calvus, P/N A10340, Penta-band SMD antenna. It is my first project with GSM device and do not know how to calculate 50 Ohm impedance feed. Can some one can help me? Send working (...)
Hello !!! I have to make a project and one of my tasks is, to calculate the open voltage of the antenna ! If we can say that the equivalent circuit of an antenna in transmit mode is a Voltage source with a Zantenna in a given frequency, i undertand that if i have a Zload=0. this is the open voltage (...)
Hi, i am a new user, my name is David and i'm from Italy. I'm writing here to get help about a circuit which i made, for instructional purposes. The following pic is the IC is a 7404 and the capacitor should be a variable tuning capacitor between 3 to 20 pF. But at the
Hello @ all Im quite new here to this board. I have heard a lot about it. Only good things :) So i hope that anyone from here can answer my question. Im an electronic technician who is really interested in the antenna technology. escpeacially printed antennas on PCB's. Therefore, i buied some book. I bought "antenna Design for (...)