Questions tagged [wifi]
Questions on the implementation of Wi-Fi (802.11) hardware. Note shopping questions are off-topic.
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Troubleshooting WiFi connection of my custom PCB - adding antenna to an ESP32 WROVER
My custom PCB sports an ESP32-WROVER-E.
I have noticed that it suffers from weak WiFi connection to the contrary of the WROVER and WROOM dev kits I have (see below for the test I wrote).
I suspect ...
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Will a 4 lane PCIe device work if plugged into a PCIe socket the only 1 lane electrically connected
I am designing a motherboard that uses a SMARC format plugin card for the CPU. This card is based on an Intel Atom x6413E CPU. The SMARC CPU card has various interfaces available, including USB2.0, ...
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How can an ESP8266 (80 MHz) read/write to WiFi (2.4 GHz) when its clock is only 80 MHz?
I don't understand how an ESP8266 can use 2.4 GHz WiFi when its clock is less than this.
This question came to me because when looking for a microcontroller. I always find it weird that 400 MHz+ is a ...
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Best antenna design with the following requirements?
I'm looking for the best antenna design with the following requirements
Small
Discrete
Wideband (LTE and WiFi)
Directional
High gain (20-25dBi with relatively high transmission power)
Could anyone ...
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Will my design work to program an ESP8285 IC?
Will this design work to program an ESP8285?
I was trying to design an ESP8285 development board for the first time.
Before sending the design to manufacturing I would like to know whether or not the ...
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2
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116
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What are the FCC rules on taking a wifi-system out of its current packaging and putting it inside another unit?
I have a wifi module (Advantech WISE-4220) shown in this datasheet.
If I remove the outer plastic casing and put the chip/antenna, unmodified, into another plastic case, am I breaking any FCC ...
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Esp32 rf design review
Preamble: this is the first time I'm working in rf circuit design, I went simple and I hope I didn't make any silly mistakes, but I still have some doubts.
I am currently designing a garden programmer ...
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Why can't WiFi hardware be used to receive radio stations?
Special hardware is needed to receive radio waves in different frequencies i.e a RTL-SDR.
My question is why can't the WiFi hardware get also used to pick up radio ...
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Preferred method of communication from the inside of a breaker box
I am developing a smart meter that would measure 3-phase current on the main circuit breaker (residential or industrial) and would broadcast the data to an MQTT server.
My question is: what is the ...
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Why does it take so long to join a wifi network? [closed]
Accessing a text-only website, including TLS handshake, averages under half a second from first GET request to completely loaded, using my none-too-fast wifi. Yet ...
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Is it possible to wirelessly bring a 2.4GHz signal through a cable?
Yes, I know wirelessly != cable.
What I have: A cheap first person view (FPV) car. The FPV part of it is standalone - essentially a camera connected to a battery-powered WiFi module. The remote ...
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What is this coaxial RF connector?
This thing appears on some ASUS motherboard and I could not find out its name.
Diameter is about 4.5mm. I need to find its proper mating part to convert this stupid thing to SMA.
I prefer not to de-...
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My ESP8266-01 gets hot after connecting CH_PD to the 3.3V
I connected VCC to an Arduino's 3.3 volt and the GND to Arduino's GND. When I connect CH_PD tothe Arduino's 3.3 volt, it gets hot. While the red light is on, the blue light is on, too. On the serial ...
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Providing power to NodeMCU (ESP 8266) from 5V output of an Arduino
Is it possible to power a NodeMCU from 5V output of an Arduino UNO board? I was trying to use the Vin of the NodeMCU as the input from the 5V port of the Arduino. It didn't work. Could anybody please ...
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WiFi Beacon working as BLE Beacon
I had this idea of a WiFi Beacon that works just as a Bluetooth BLE Beacon. I tinkered around with some DIY Bluetooth beacons, like building my own iBeacon for distance measurements.
But my questions ...
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Using PCB and external antenna at same time for WiFi
If you use a design with an ESP8266 is there a possibility to use an external antenna (u.fl connector) with a PCB antenna at the same time without using a solder bridge or jumper?
Generally speaking, ...
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How should I route the ground plane under a RF trace with a LC balun?
I'm designing a PCB with a ESP32-PICO-V3, with a RF output to a 50 Ohms U.FL (Micro-Coax) connector. The chip supports WiFi and Bluetooth in the frequency range 2.45 +/- 0.45 GHz.
Right now, I have a ...
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WiFi path loss formula
I am referring to the Wi-Fi path loss formulas:
2.4 GHz: L = 46 + 25log(d)
5 GHz: L = 53 + 30log(d)
I see they slightly differ from the Free Space Path Loss formula. I want to know why and how did ...
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How to upload new firmware to Ralink RT5350F board
I took apart old Edimax SmartPlug (model SP-1101W) to find out that the brain of the device is Ralink RT5350F chip conviniently placed on removable module board:
The board has two rows of 14 pins (28 ...
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PCI wifi board (Ubuntu OS) to experiment with microwave signals
I would like to use a PCI WiFi board under Ubuntu OS to experiment with microwave signals.
I would like to be able to access the board through the software driver and be able to turn on or turn off ...
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How can Bluetooth, WiFi, ZigBee use the same frequencies but have different area coverage?
What makes radio frequency spectrum cover a larger distance for data transfer?
Bluetooth, WiFi and ZigBee all use the same band (2.4 to 2.5 GHz) but their coverage area is different. Why?
If it's ...
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WiFi (2,4G) Antenna Isolation. Why 3 capcitors version does not work
I need to isolate the antenna from the WiFi transmitter. There are some solutions on the market but none suitable for my application.
So I have started some experiments.
2x PCBs creating DIY ...
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Is this esp8266 antenna layout any good?
It's the first time I do a design based on ESP8266 ic (not module) and was wondering if this layout is permissible for 2.4Ghz applications. I acknowledge that the trace must be a bit wider to comply ...
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Who pays royalties to whom for the patents that form 802.11 standard [closed]
This is my first question here and it‘s not even electronics related. Shame on me!
I think it's a very important question to engineers like me who think about the idea of commercializing a device with ...
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What does a MIMO-capable device do with a SISO AP?
I'm studying Wi-Fi RF.
I was wondering how antennas work in different situations.
If a device with two antennas and which support MIMO operation is connected to single antenna AP, will the device try ...
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2
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Dwell time in wireless communication
In wireless communication dwell time is defined as the amount of time a device uses a particular channel. If we take the case of a ...
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What is the relation between symbol duration and subcarrier frequency spacing in OFDM?
What is the exact relation between symbol duration and frequency spacing?
You may know in WiFi6, about 11ax band, there are more sub-carriers compared to WiFi5 because of using shorter frequency ...
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Lazer wifi connection [closed]
Would it be possible to create a Wifi cable that uses lasers to send information at light speed?
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Is there a wired block wifi signal amplifier?
I already have a directional wi-fi 2.4 antenna with a gain of about 25 dbi. I also have an adapter, however, the power of the receiver/transmitter is not enough.
My apartment is on the 9th floor, ...
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Can ESP8266 be hacked? [closed]
I have a ESP8266 linked to my home wifi. Is it possible for someone from outside to have access to it and further is it possible to hack into my network? If yes how do I protect it ?
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MU-MIMO - do all antennas stream in different frequencies?
I have few questions on how MU-MIMO in WiFi works.
Do all antennas stream in different frequencies or stream in same channel but different sub carriers(OFDMA?)
Do MIMO antennas always work in OFDM ...
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Why does my Ethernet upload speed go to 0 Mbps when connecting an RGB LED strip?
I recently installed the following RGB LED strip on my bedroom's ceiling:
The computer and the lights share the same electrical connection. However, everytime I plug the lights into the wall my ...
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Arlec grid connect bulb and power points DC convert smart WiFi hack
These devices works off 240V AC.
I was looking to convert them to run off DC and keep the grid connect app function.
https://www.bunnings.com.au/arlec-9w-950lm-4000k-grid-connect-bc-smart-...
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Adjusting Bluetooth Speaker Channel [closed]
Current Bluetooth devices are supposed to have frequency hopping technology built into them. However, my Oontz speakers skip when I use the apartment complex WiFi. Most likely, it is because they ...
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What is it called when a WiFi chip advertises its own SSID so users can connect
I am not sure which stack should I post this, but here is my question:
when you buys these WiFi-enabled gadgets, when they turn on they advertise a SSID where you can connect to it and enter your ...
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Simulate WiFi Stations for testing the AP
I was thinking if I can simulate WiFi stations(around 5 numbers) in my laptop, that I can try associating these stations to my AP and load test the AP. Could some one suggest on this or is there any ...
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Why does a soldered IPEX MHF4 (WIFI card) connection result in signal attenuation?
In my laptop, the WIFI card was connected to the 2 antennas by IPEX MHF4 connections, which look like tiny coax connectors. Unfortunately the antenna connectors got broken, so I have removed them and ...
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Does the Qualcomm MDM 9207 chip have WiFi, Bluetooth and GPS?
I am researching about the Qualcomm MDM9207 chip and I have some questions regarding it:
Does this chip contains a WiFi module or do we have to integrate it outside?
Does this chip have a Bluetooth ...
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2
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Transfer WiFi to a PC using a ESP8266
I have a PC with no WiFi adapter. Is there a way to achieve such a setup where the ESP8266 is connected to the PC with a serial connection and the PC can connect to the internet using the WiFI of the ...
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CSMA/CA - What happens if a faulty WiFi station does not silence itself when an RTS/CTS is received?
In a WiFi network, assume a WiFi station does not silence itself for an RTS/CTS reception from other stations and it keeps on transmitting. I have few questions related to this scenario,
1.Will that ...
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WL1837MOD SDIO Control(or Wifi module in general)
There are a number of wifi module which are controlled by SDIO(as an option). I am using the WL1837MOD as a specific example but I welcome more general answers.
All the documentation for this chip ...
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ESP8266-12E unstable WiFi connection (Need feedback)
i have made a small circuit using ESP-12E here is how my circuit looks like:
Here i have kept in mind that wifi connection should be stable, still i am not able to get the stable WiFi connection. ...
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In wifi modules what does the shield have to protect?
All wifi modules have a shield over the chip but what I’m wondering is if the track to the antenna need to be shielded or is it just the chip that needs shielding ? Thanks Ben
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Dual sided uFL connections
I am laying out a dual sided PCB, 1.6mm (62mil) thickness. I'm wondering if I can drop a via on the feedline to a uFL connector and place another uFL on the other side. Will this cause unacceptable ...
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Shouldn't an antenna with a higher gain provide a stronger signal in the designed direction?
I have a Wi-Fi access point with six antennas: three for 2.4GHz, and three others for 5GHz. The spec of the access point indicates that the gain is 4 dBi for 2.4GHz antennas, and 6 dBi for 5GHz ones (...
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How does a wifi antenna work?
let's consider a common wifi antenna (used in routers) like this:
I don't understand some its basic features:
1) Is it a dipole or monopole antenna? I see only one conductor, so I'd say it's a ...
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Does the ESP32's Long Range capability work with most smartphones?
Recently discovered an ESP32 can be its own access point (controlling or displaying data wirelessly through a web browser not connected to Internet). It also has long-range capability:
Long Range (LR)
...
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How does my 802.11 a/b/g/n wireless card determine the modulation to use?
I was thinking yesterday about how the 802.11 a/b/g/n standards all use different modulation schemes, but my wireless card manages to detect frames from networks that may use any of those modulations. ...
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Is interleaving used in MIMO?
Correct me if I'm wrong, this is my understanding of MIMO:
Is this how MIMO is able to increase data rate?
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