Antenna (radio), also known as an aerial, a transducer designed to transmit or receive electromagnetic (e.g. TV or radio) waves. -Wikipedia

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How to Calculate the impedance of a voltage doubler Circuit?

How to Calculate the impedance of a voltage doubler Circuit? When I connect the RF in/out of 50 Ohm to this circuit there should be impedance matching so can anyone help me out how to calculate the ...
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2answers
59 views

What is load on an antenna? Is it safe to short the antenna port?

On the readme page of https://github.com/pwarren/rtl-entropy, it says: If you're serious about the cryptographic security of your entropy source, you should probably short, or put a 50 Ohm load ...
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1answer
31 views

TV Antenna Signal Strength Fluctuates Repeatedly [on hold]

I have an LCD TV... about 8 years old maybe. Since I cut cable and only have internet (TWC), I bought a Mohu Leaf Metro. The video is choppy and the sound cuts out constantly. I tried reading up on ...
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32 views

Xbee pro 900 MHz long range just reach 950m

Thanks for your time. I´m developing a communication system that need to reach 1.3km to carrier water to a native community in Colombia. I´m using the Xbee pro 900 ...
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1answer
23 views

matching network design for transceiver with differential outputs

I'm trying to learn about matching networks. I have a 2.4GHz radio chip with differntial TXP/TXN outputs, and RXP/RXN input. These both share the same single ended antenna. I've been reading and I ...
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1answer
48 views

WWVB Antenna Reciever 1st Amplifier stage, no signal

I made a high input impedance JFET CS amp as the 1st amplifier stage for a 60kHz Loopstick Antenna. I am using an RF JFET (J211) and ceramic capacitors. The only signal I see is a 60Hz sine wave ...
2
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1answer
32 views

How to calculate or should I measure impedance for 1/4 Wave monopole?

I have this odd design that I'm trying to improve the antenna on. It has a mother board and a radio board above it, and it's densely packed with components. My idea was to try a monopole in the ...
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1answer
42 views

WWVB simple receiver help

I am trying to experiment with WWVB receiver design... The antenna I am using is from another WWVB receiver module. It is a loop antenna with a capacitor that I assume is tuned to 60kHz. Questions- ...
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3answers
70 views

Are the same type of antennas used for receiving and transmitting?

Short version: Is the same antenna type used for transmitting as is used for receiving if the frequency is the same? Long version: My garage door opener uses 433 MHz to receive signals from the ...
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2answers
73 views

Increase range of 433MHz remote sensor [closed]

My question is similar to this one but with some differences. I have wireless weather station with 3 remote 433MHz sensors so I cannot change the protocol and program the controllers. Also I'm new to ...
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2answers
39 views

WWVB antenna interferance from AC/DC converter supply

I'm working on a design that uses a WWVB antenna receiver.... The WWVB antenna is a small (~ 1/4" x 4" rod). Size is not a constraint so I could make it much bigger if a I half to. The design is ...
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0answers
53 views

FM Receiver Antenna Reception Check

I have implemented the following FM receiver circuit by radioshack: http://web.archive.org/web/20090121123846/http://braincambre500.freeservers.com/rss(1)(1)(1).htm I haven't been able to receive ...
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1answer
54 views

Using both ground pins on uFL connector

I would like to add an Hirose U.FL antenna connector to my PCB. I have no previous experience of using them, so I would like to now if I should connect both of the GND pins to the PCB ground or it's ...
0
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0answers
25 views

Reflector with Ferrite Antenna?

Would a parabolic reflector have the same effect using a ferrite antenna? I didn't see anything online, but I can think of reason why it would work. I rigged one up out if sheet metal and it seems to ...
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1answer
32 views

ferrite antenna impedence matching

I am using a WWVB receiver for a project I am working on. The ferrite antenna that the receiver came with has terrible gain and I want to make one that is several times larger. I know how to make a ...
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1answer
55 views

Chip antenna, what to do with power and bottom planes

I'm designing a board which uses a chip antenna. According to the datasheet, there should be no copper on all layers under the antenna. There's also should be some ground plane on the top layer with a ...
0
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1answer
34 views

Correct Notation of Radiation Pattern of an Antenna

I have a confusion regarding the notation of radiation pattern of an antenna array. Some literatures use, say, $$F(r,\theta,\phi)$$ to denote the same while others use $$F(\theta,\phi)$$I would ...
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1answer
35 views

Transmission lines/Antennas power delivered to a load, why halved?

When seeing transmission lines and antennas in class we saw that the power delivered to a load is equal to: $$ P = \frac{1}{2}\cdot \left | I \right |^{2}\cdot Re\left \{ Z \right \} $$ Where I is ...
3
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1answer
57 views

Effect of bad antenna design on chip behaviour

I have designed a PCB for TI's cc3200 using recommended design specifications. The chip performs correctly when i use functionalities like GPIO read/ write, UART communication, but as soon as i use ...
3
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1answer
70 views

How to automatically switch RF path to external antenna

I'm designing a circuit that has 2 antenna options for one transceiver @ 1.6 GHz. One antenna is internal and is the default RF load. Another antenna is external - to be attached by the user if ...
2
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1answer
58 views

Adding antenna gain to RX and TX sensitivity

Let's say I have a transceiver with 10dBm of TX gain, and an RX sensitivity of -10dBm. If I then attach an antenna with a gain of -2dBi do I then have an RF output power of 8dBm and an RX ...
3
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1answer
69 views

Does my PCB Require 50 Ohm Impedance trace even if i am using external antenna?

I am using the Quectel M95 GPRS Modem in my PCB, and the hardware reference guide says "The Pin 39 is the RF antenna pad. The RF interface has an impedance of 50Ω. " I am using a u.efl connector and ...
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115 views

Radar antenna for distance measurement

I am working on a project where we have decided to use radar to measure the distance of an object from the device. I have been using Infineon's BGT24MTR11 (24GHz) evaluation board, (Sense2go), which ...
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1answer
53 views

GPS antenna type

i want to interface a gps module and an antenna. I found this kind of antenna (example) It does not mention its type. Is this an active or a passive antenna? How to be able to know by myself without ...
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1answer
32 views

add a second antenna

My application requires to connect through Bluetooth reliably. I have an issue is that the receiver is not always in line of sight and when not, I experiment connection drop. I would like to have 2 ...
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1answer
93 views

What is the best way to connect over 2km distance without line of sight using wireless? [closed]

I need to connect my home internet to the farm. Home has internet connection but farm is in forest area so cannot have internet connection. So I need to setup connection to share my home internet to ...
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1answer
61 views

RFID chessboard

I want to make a electronic chessboard that detects the position of every piece on the chessboard. So I did some research, and one way would be to put RFID tags under every chess piece. Each tag ...
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2answers
64 views

Would it be possible to design a SoC have to two antenna? [closed]

If you use an actual SoC such as the Qualcomm Snapdragon Processor for mobile communications would it be possible to have two cores both sharing a common IO (Cellular/WiFi/GPS/Bluetooth) integrated ...
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1answer
54 views

Quad Band GSM PCB Antenna

I am making a GSM + GPS Board, and we don't want to put an external antenna on top of it via any sort of connection. Primariliy to reduce the cost. I've seen a VTS system with an onboard antenna ...
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3answers
51 views

Gate opener antenna orientation

Objective Our gate opener remote receiver works much better with the antenna horizontal than vertical? By much better, I mean 300' vs 100'. Why? Background The distance the remote will operate the ...
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1answer
40 views

Interpretation of radiation resistance in receiving mode

Assume we have an antenna in receiving mode, connected to a matched load. The equivalent circuit is a voltage source in series with the antenna feedpoint impedance and the load impedance. As we know, ...
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0answers
59 views

Designing a GPS Antenna Concept

I'm working a GPS circuit (for a handheld device that will ironically be in bags or pockets most of the time) which communicates with wifi networks. I thought a great deal about the required ...
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29 views

MOS parallel to antenna - antenna clamp, antenna modulator

I would like to understand the following thing: in RFID passive circuits there are MOS transistors, which work as a clamp or a modulator. These transistors are in parallel to antenna. Drain is ...
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1answer
197 views

How to send out 60khz signal from antenna?

BACKGROUND In Japan there are radio-controlled clocks. Time is synchronized by 40khz (in west Japan) and 60khz (in east Japan) radio, which is broadcast from transmission towers. The signal is known ...
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1answer
92 views

Will this antenna even help?

I am using ESP8266 (esp-07) in a project. I was facing connectivity/range issues with my old router. So, I am planning to use a PCB antenna with esp. This is how it looks: Here is the mechanical ...
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1answer
43 views

Si4012 loop antenna question

I don't get how the antenna design on page 8 of the datasheet is suppose to work. I know that the feed trace from VDD works as an inductor at high frequencies, but how do I design an antenna like this ...
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0answers
42 views

GPS Active Antenna Circuit

I'm adding an active antenna to a design and had a few questions. Based on multiple data sheets for similar products, everyone uses the same simple DC supply with a RF blocking inductor and DC ...
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0answers
42 views

Antenna length and faraday cage

I am making a project with a device emitting at 433.92 MHz This device is located inside a metal box so the internal antenna does not work well due to the faraday cage effect. To improve that, I need ...
2
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1answer
65 views

RF switches for RFID HF 13.56Mhz

I would like to use 1 RFID reader (13.56Mhz, protocol iso14443a) with 2 antennas in a way that I can recognize the location of the tags- if they stand on antenna #1 or #2. For that, I tried to use 2 ...
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1answer
95 views

Antenna Performance with plastic fasten

I need to put dipoles antennas in a restricted area with lot of movement. I'm wondering if I fasten the end of the antenna will affect performance, because the fasten needs to be grounded. Is like ...
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0answers
45 views

Mechanism of a pringle antenna?

I'd like to DIY a WIFI antenna out of a pringle can. Although there are lots of info online to teach you how to assemble one, but none of them explains the mechanism of it. My questions: 1) What is ...
0
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1answer
42 views

VNA for antenna measurement

I'm trying to learn how to use a VNA to get the impedance and smith chart for a given antenna. I'm working at 2.4Ghz do I just need a VNA that operates up to 3GHz or is there some reason that I need ...
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1answer
43 views

Antenna efficiency

When an antenna datasheet states that it has 50% efficiency, I understand that to mean only 1/2 of my transmit power will actually be radiated. Does it meant the same thing when using that antenna ...
2
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1answer
79 views

How to make an antenna for a custom frequency range? [closed]

I'm interested in omnidirectional antennas or maybe I should say antennas that don't care too much if you move/rotate them. Now how would you build a good antenna for a specific frequency range. (e.g ...
0
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0answers
70 views

3G - Ideal antenna size and amplifying signal?

I am thinking about building my own portable 3G router box. So that I can finally have 3G in badly covered areas and on trains. The idea is simple: [Laptop, Phone, ...] <-> via wifi <-> ...
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1answer
47 views

How to avoid multipath noise

I have a device that broadcasts BLE advertisments, I am trying to measure the RSSI level of the broadcasts on another device (I am trying to do indoor triangulation for location estimation) When I ...
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1answer
33 views

Predicting bit error rates for RF communications [closed]

I am trying to estimate what the approximate bit error rate for a given antenna configuration would be. Specifically, suppose I have two parabolic dish antennas pointed at each other. If they are ...
2
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2answers
92 views

How to make radio reception better with antenna 133 cm long [closed]

My low cost FM radio receiver Philips MCM129 is not receiveing some radio stations well. It has antenna made of about 133 cm long thin insulated wire which I suspect is the rason of the problem. Can ...
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1answer
29 views

Mobile Phone Signal Flash Light 3-12V - not working. Circuit viable?

Another ebay-heist that does not work as adverstised. I build it, and tested with some normal g3 cellphones, but no dice. My antenna at J2 is an 8cm long wire (not really lambda/4 of anything, but i ...
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1answer
26 views

Distribution of phase errors

I have to implement a phase error model to see effect of phase errors on antenna patterns. However, the distribution of phase errors isn't provided to me. I am not sure whether to assume the phase ...