Questions tagged [antenna]

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

Filter by
Sorted by
Tagged with
0
votes
1answer
21 views

What to be concerned about with NFC using external antenna located off board?

Working on an NFC application (NFC tag) and it looks like the NFC antenna will be located off-board. This is a sticker type of antenna. The concern that I am possibly having is that I need to run some ...
0
votes
0answers
34 views

RF Antenna 50 ohm controlled impedance design

this is my first time doing RF design and I'm currently using ThingMagic Nano M6E RFID module and in the process of designing a 50ohm impedance circuit/trace from the IC to the antenna. On their ...
0
votes
0answers
16 views

Ferrite underlay impact on chip antenna performance

I'm designing a small wireless chargeable IoT device which also has TX/RX in subGhz frequency (LoRa). The idea is to stack everything on top of each other starting with charger RX coil, then ferrite ...
0
votes
0answers
28 views

How could I give pad to this antenna section?

I have a SC20 schematic diagram. From the diagram, there is an antenna section as shown. How can I give a pad to this antenna for drawing PCB in EasyEDA? The schematic provided some information like 1....
0
votes
2answers
57 views

DIY Antenna with minimum components for proof of concept

I am going to try a simple transmitter-receiver(assuming receiver circuit is same) circuit using the following circuit: Now, I have got the BJT part and the LC oscillator part figured out. What I ...
5
votes
1answer
412 views

How to design a large 125kHz loop antenna for long range RFID application?

I am designing a large loop antenna working at 125 kHz. To maximize the range of my system I am aiming for 1m diameter loop antenna with as many turns as I can allocate (e.g. ~100 for 18 AWG). I have ...
2
votes
4answers
125 views

Why do we ground radios? [closed]

Why do we ground radios? As far as I know an antenna is an open circuit... So we just need to put and filter to remove noise and we are ready. However in most schematics I see the antenna is grounded. ...
1
vote
1answer
52 views

what are these two fm antenna connectors? How can I join them?

One of these connectors is the type that plugs into my receiver's FM antenna input, and the other is an aftermarket FM antenna output connector. I think the one with threads is called "type F&...
0
votes
1answer
121 views

Is it possible to reduce range of an RF receiver or transmitter for LED Strip lights?

Background: I recently purchased a couple of strip led lights with remote. These were installed in different rooms. Problem: The remote seems to be RF and not IR, thus all the lights in various rooms ...
1
vote
0answers
27 views

How can one compare resonant and non resonant antenna based on parameters like Directivity, Radiation resistance, Cross polarisation, Efficiency?

Basically I want to make a choice between two antennas when ample space is given objectively based on parameters 1.Directivity 2.Radiation Resistance 3.Cross Polarization ratio 4.Loss resistance I'll ...
2
votes
1answer
157 views

What is difference between resonant and non resonant antennas?

I don't know if it's right place to ask it, but I searched google and books the answer I get seems to be like resonant antenna have small bandwidth and have standing wave instead non resonant antennas ...
0
votes
2answers
55 views

Is my antenna faulty?

I'm trying to build a receiver signal circuit that will operate at 125khz. I'm using this receiver chip and this 125khz antenna. I tried breadboarding: After connecting AS3933's VCC, GND, CS, SCL, SDI,...
0
votes
1answer
51 views

HB100 Range extension with Dish Antenna

I have interfaced HB100 sensor with ATMega Microcontroller. It easily detects my hand movement upto 5-6 inches only. I want to extend range of the sensor so that it detect movement upto atleast ...
1
vote
0answers
41 views

How to increase the range of BLE chip RN4871

I have an RN4871 Bluetooth chip and integrated it with my micro. The chip is scanning for nearby BLE devices and reporting them to the host micro via UART. However, I see that the range of this chip ...
0
votes
1answer
36 views

Please help identify the positive and ground for BLE antenna

Please help identify the positive and ground for adding an external BLE antenna, after the chip antenna was removed. I am connecting an external antenna (not the removed one) to this Nrf51822 BLE ...
0
votes
0answers
71 views

Near-field microwave antenna design

How to I design an antenna which produces a strong field within the antenna, but doesn't radiate out or reflect back to the source? (as much as possible) I'd like ideally to have a planar structure (...
0
votes
0answers
38 views

What are the important values of GNSS antennas

I want to compare different GNSS antennas, but I don't really know what values to compare. How can I compare them with datasheets looking like this? Edit: The antenne will be used on a rover that will ...
5
votes
1answer
52 views

RFID antenna multiplexer

I am working on a project where I need to use a single RFID reader to read tags from 4 different positions (6 cm apart). It is OK to only read one tag at a time, so I figured an RF-compliant ...
1
vote
0answers
16 views

Confusion regarding antenna element to element isolation in an array consisting of say 2 antennas

suppose one has an array of 2 isotropic antennas used for spatial diversity , which means that they need to be as uncorrelated as possible, how does the coupling or isolation between them affect the ...
0
votes
3answers
110 views

How can a crossed dipole (turnstile) antenna be omnidirectional in 3D?

A crossed dipole or Turnstile antenna is said to not only be omnidirectional in the plane of the two dipoles, but its pattern is roughly spherical, there's no null along the axial (boresight) ...
0
votes
1answer
34 views

Circuit for selecting between PCB antenna and external

I'm just developing the second iteration of an 2.4Ghz sensor and receiver set. Because I can't afford the expensive development path of a big commercial project and because the environment these ...
2
votes
2answers
78 views

AM radio antenna optimization

I am an RF noob and am trying to understand if optimizing an AM crystal radio antenna (maximizing the signal transmission from the antenna to the LC tank) is practical, or even makes sense. Here is a ...
1
vote
2answers
48 views

Radio Waves: Spark gaps vs general wireless radio antennas?

I was recently told by a friend who teaches college physics that "in reality radio waves are only generated when an electric current is made to move violently through a conductor". He went ...
1
vote
1answer
30 views

1/4 WL Strip Antenna Questions

I'm designing a module around the nRF52832 SOC and I need some help regarding the single-ended microstrip antenna. I have three questions, so please bear with me. The first question is about how wide ...
2
votes
1answer
84 views

Can RFID read stacked cards?

I want to create a project that will read playing cards that have integrated RFID. If I put multiple cards on top of each other will it still be able to determine the stacked cards? what if the cards ...
0
votes
0answers
22 views

Designing 125 KHz RFID Rectangular Spiral Antenna for FPC

Am trying to design a rectangular loop antenna similar to this paper from Melexis for an HF antenna design, however i want to implement something similar but for 125 KHz rectangular antenna. Now using ...
1
vote
1answer
53 views

Which parts of this U.FL laptop wifi antenna need to be exposed?

I got these wifi antennas for use in a small metal computer case. I'm cutting some holes in the case to give the antennas exposure, but I'm not sure what parts of the antenna need to be exposed. As ...
1
vote
2answers
115 views

At what range can I transmit with this antenna?

I would like to transmit data at 125 kHz frequency. I'm wondering what is the realistical transmission distance that can be achieved with this antenna: It's a rectangle shaped 9x12cm coil antenna. ...
1
vote
1answer
74 views

Using WiFi Antenna for 5G Mobile Network?

I moved to an apartment located in a basement of a complex. I had to build a setup with a set of 2 external LTE (4G) antennas Wilson Electronics Wideband Directional Antenna 700-2700 MHz Wilson ...
0
votes
0answers
36 views

Typical half-wave dipole antenna parameters

From my bachelors degree, I have learnt the fundamental theory behind antennas. One of the main types is the half-wave dipole antenna. We've studied its radiation pattern (isotropic) and how it varies ...
1
vote
3answers
86 views

How to make sense of EIRP?

I've been introduced to the concept of equivalent isotropically radiated power (EIRP) and so far I've used it to calculate RF power density at distance of 100m radiated by a directional antenna with a ...
3
votes
1answer
92 views

Why exactly is a Hertzian dipole inefficient?

http://farside.ph.utexas.edu/teaching/em/lectures/node94.html states: Note that the formula (1100) is only valid for \$l\ll \lambda\$. This suggests that \$R_{\rm rad} \ll R\$ for most Hertzian ...
1
vote
1answer
61 views

How to add a simple ESD protection to RDA5807M FM tuner antenna pin?

I am using an i2c controlled FM tuner IC (RDA5807M) in a DIY fm radio, but I am a little bit worried about ESD protection on the Antenna line (A headphone lead being used for this). Can i add standard ...
0
votes
1answer
43 views

How do I add an external Bluetooth antenna to this circuit?

I want to disconnect the PCB Bluetooth antenna and add a U.FL SMD for an external antenna. Can someone please advise me what to cut/add/solder?
0
votes
2answers
79 views

Designing on-chip antenna [closed]

I want to design on-chip antenna (that is, antenna on PCB itself). Is it also called microchip antenna ? Can anyone provide me details and/or steps as to how to design on-chip antenna? How to proceed ...
0
votes
1answer
78 views

What is the name of antenna and connector in the image

Below is the image of a GPS module. I have highlighted the antenna in the yellow box: What is the name of the antenna in the yellow box (Question 1) ? Is the type of this antenna ...
0
votes
0answers
32 views

Is an EM vector sensor antenna for DoA at 900 MHz feasible?

I'm contemplating antenna array designs for an easy-to-setup beam forming receive SDR system for DoA (direction of arrival) at the ISM band (likely ~900 MHz). I saw the 3d vector antennas used for the ...
1
vote
1answer
65 views

Random wire antenna - why only one wire?

If my understanding of AC and the generation of electromagnetic radiation is correct, then a complete circuit encapsulating power source and resonator is required (a closed circuit). How then can a &...
0
votes
0answers
15 views

Polarization loss factor for antennas

What would be the polarization loss factor, if transmitting antenna is circularly polarized and receiving antenna is linearly polarized, but they are aligned in such a way that maximum radiation ...
0
votes
1answer
81 views

How do I switch a PIN diode using a TTL control signal?

I'm designing a transmit/receive switch for an antenna using a PIN diode. The PIN diode I'm using is UM7512 make: Microsemi. I need to switch between -400V (off) to +5V (on). The switching time should ...
0
votes
1answer
57 views

What's a pigtail with regards to antennas?

Can somebody explain to me what a pigtail is with regards to antennas? I bought a 434 MHz rod antenna with an SMA plug and what I got was the antenna as expected and another short piece of wire with ...
1
vote
1answer
30 views

Antenna Factor unit and calculation

The antenna factor equation in a 50-ohm system is expressed as: $$AF={9.73 \over \lambda*\sqrt(Gain)}$$ Where Gain is in dB, the wavelength in meter and the calculated AF is in dB/m. $$$$ First, How ...
0
votes
1answer
91 views

RF Matching Problem

I am having some fundamental issues trying to create an impedance matching network for an 868MHz antenna, I have a PI network between the antenna's connector and the antenna feed point I have measured ...
1
vote
3answers
72 views

Do beam-forming devices expect a particular antenna configuration?

Do beam-forming devices expect a particular antenna configuration? For instance, do they expect the antennas to be a certain distance from one another? Or parallel to one another? Etc. Background Info:...
0
votes
1answer
47 views

How to choose an appropiate antenna?

I want to increase the Bluetooth Low Energy transmission range of my ESP32 with IPEX connector. How can I select the right antenna? Do I have to take a look only at a 2,4 GHz WiFi antenna, the antenna ...
6
votes
2answers
951 views

How to compare a magnetic loop antenna to a conventional antenna

I want to build a compact 1 MHz receive coil (antenna for very near field). For that I need to make a choice on whether to build a simple RF coil only consisting of wire and capacitors or using a coil ...
0
votes
0answers
42 views

If planar coil is used as antenna, then what kind of antenna should it belong to?

The image below shows the example of planar coil I mean. In my search, I found it is similar to NFC antenna, or in the other words, loop wire antenna. However, I don't see there is a hole in the ...
0
votes
2answers
68 views

Antenna Tuning for Source Impedance not equal to 50 Ohm

I have designed a setup for 433.92MHz wireless device (a key fob). The source impedance is not equal to 50Ohm. The load impedance may or may not be 50Ohm depending upon the choice of the antenna. For ...
1
vote
0answers
34 views

Calculating Antenna Directivity Numerically

The equation for peak directivity of an antenna is this (example source) $${D = \frac{1 }{ \displaystyle \frac{1 }{4 \pi} \int_{0}^{2\pi} \int_{0}^{\pi} |F(\theta,\phi)|^2 sin(\theta) \, d\theta d\...
0
votes
0answers
35 views

What is the formula for measuring Antenna range?

According to example 1 of this website The formula for measuring the antenna range is this => D = radical(2hR) which R is 6400km for earth and h is the height of our antenna from ground. So if we ...

1
2 3 4 5
28