Questions tagged [wifi]
Questions on the implementation of Wi-Fi (802.11) hardware. Note shopping questions are off-topic.
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1answer
49 views
What is the major difference between a WiFi and RF Module?
In an interview recently, someone asked me what is the major hardware level difference between a WiFi module (ESP8266) and RF module (nRF24L01+) that I had used in my projects.
I mentioned that both ...
0
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1answer
36 views
Can I use a Ku band satellite dish for Wi-Fi?
Satellite TV works at 18-24Ghz and WiFi at 2.4Ghz, will a T.V dish antenna work for WiFi?
Diameter of the dish is about 60-90cm
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0answers
31 views
Wiring WiFi SD card to TF
I am trying to wire a WiFi SD card so that it will insert into a TF socket. I connected each pin to its equivalent, with an extra GND on the SD card connected to the same on the TF. It's not working, ...
0
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3answers
56 views
Does data rate increase with channel frequency?
It is commonly said that a higher channel frequency implies a higher data rate. For example, in https://www.howtogeek.com/222249/whats-the-difference-between-2.4-ghz-and-5-ghz-wi-fi-and-which-should-...
0
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1answer
36 views
Using ESP32 as a2dp sink and access point at the same time
I am trying to make a project where bluetooth and wifi collaborate with each other. Precisely I want to use the a2dp profile to stream the music to one esp, from there via UDP sockets to N esp's.
I ...
0
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1answer
63 views
WiFi signal strength distibution
I wonder how wrong is it to assume that in general case for a non-directional antenna the wifi signal level distirubiton can be described with the function
\$y(x) = b - \frac{k}{(x+a)^2}\$, where x is ...
0
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1answer
60 views
2.4 GHz Chip antenna layout
I am am new to RF design and I need to place a chip antenna due to space limitations. The only antenna that is easily available to me has a very weird layout. There is no physical connection from the ...
0
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0answers
35 views
Wifi versus Zigbee versus Bluetooth for real-time data sampling
I am working on a project that I would like to send and receive data between a microcontroller (ESP32) and a PC. The microcontroller supports both Wifi and Bluetooth. If I send one single data point (...
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2answers
101 views
How same frequency signal with different power are produced?
My router have settings to configure transmission power and as i know energy of a signal is given by
$$
E = h\nu
$$
where
\$E\$ is the energy of the signal,
\$h\$ is Planck's constant,
\$\nu\$ is ...
0
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0answers
41 views
Wifi coaxial cable type unknown
Quick question, I was unable to identify the coaxial cable type used in wifi devices(routers ,tablets,etc.) , very thin grey cable approximately 1mm in outer diameter, I need to know the type so I can ...
0
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1answer
29 views
How to link 3 RF transceivers to 1 antenna
I'm not an RF designer, so excuse the newbie question:
How would I link three transceivers, say WiFi and two separate bluetooth transceivers, to a single antenna.
I have found a 3-way combiner ...
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0answers
31 views
Creating a 90 deg. circular polarized phased array using two Yagi
Imagine two 2.4Ghz Yagi (WiFi), one mounted with blades horizontal, the other's blades vertical, both aimed at the same target. Each has the same leg of its coax cable (Xmeasurement) longer (either ...
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0answers
5 views
ESP-01 not working correctly when acting as AP as well as station
I am experiencing this potential problem with ESP-01S ESP8266 module. I am controlling it via Atmega328 micro-controller. Issue occurs when it is configured as both soft AP and a station and when ...
0
votes
1answer
58 views
What is typical interface for WLAN chipset on a modern smartphone?
Taking into account nowadays Android smartphones support WiFi 802.11ac, what interface is being used for interconnecting of WLAN chipset with Application CPU? Is it SPI or some other? Is it OK to ...
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1answer
21 views
WiFi IC with minimal controller features [closed]
I do not want to program my esp8266. Are there any alternatives to it with lesser controlling abilities (I/O lines, Flash, etc)?
0
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1answer
30 views
Why microstripline is compulsory to generate high frequency signal in the range of 2 Ghz or more
I would like to understand why the UHF (Ultra High Frequency) band in the range of 1 Ghz or more like 2.4 Ghz or 2.6 Ghz require microstripline to generate such signal frequency?
Is there any ...
0
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1answer
76 views
Solder or Adhesive for Wifi Module
I am replacing a wifi module for my smart tv. I have any never done this before and want to know if I need to solder the two components together or just use an adhesive like in the old module. The ...
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votes
1answer
73 views
What will be the simplest circuit that outputs 1 when it receives a predefined WiFi packet? [closed]
What will be the simplest circuit that outputs 1 when it receives a predefined or pre-programmed WiFi packet? Lets suppose that I connect this circuit to an appropriate antenna then I want that my ...
0
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1answer
52 views
Control ESSP8266 IOT board over cellphone hotspot wifi [closed]
I am using the following code in order to control my ESP8266 using my cellphone hotspot.
...
0
votes
1answer
325 views
How to send data to an ESP32 with as little delay as possible from an Android app [closed]
I have an ESP32 module. I want to send data to it using an Android app.
I tried using http but the delay is big especially since I want to send about 20 values per second with a delay between 50 to ...
0
votes
1answer
74 views
How does Wi-Fi deal with multiple frames received at once?
Right now I'm trying to establish a network of 30+ transceivers with NRF24L01 modules - one of them acting as central. However there are big problems, whenever two or more nodes try to send data to ...
0
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1answer
69 views
Video stream through microcontroller wifi
i am currently following an education in technical informatics(mostly micro controllers programming).
I always wondered how to send video frames though an cheap micro controller, but after googling a ...
0
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1answer
63 views
Program a Wi-Fi Module using a STM32F4
I am desgning a sensor which reads data from 6 transducers and is desired to send them over Wi-Fi to a host pc. Because of space limitations, I have to design my own pcb with microprocessor instead of ...
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2answers
62 views
How to fix this wifi FPV antenna
I do not know much about antenna's. A wire broke off of a Wifi antenna, being part of a video transmission unit of a quadcopter.
The short grey colored wire on the right side of the picture broke off....
2
votes
1answer
613 views
I'm trying to identify this WiFi / Microcontroller without any luck
I purchased these TanTan Smart electrical outlets with the hopes of finding an esp8285 or esp8266 within them. When I opened one up I was greeted by something different, and am trying to determine ...
0
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1answer
81 views
What is the relation between carrier signal and local oscillator in RF system?
I have a confusion between the carrier signal and the local oscillator and based on my understanding, IQ signal (data) is mixed with carrier signal to become a modulated RF signal and before ...
1
vote
2answers
87 views
SPI, RS232 and DMX-512 data signals beneath the ESP8266-WROOM-02 Wifi antenna
I am working on DMX-512 Controller, which will accept commands for driving Addressable LED strip (GE60RGBW8812A) via ESP-WROOM-02 Wifi Controller and I have several data lines (...
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vote
0answers
46 views
Active phased antenna array for Wi-Fi efficiency compared to a directional antenna?
I'm interested in mesh networking of poorly controllable autonomous aerial vehicles (like blimps), so i wonder whether it is viable to use a phased antenna array versus a few traditional directional ...
0
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2answers
95 views
How to detect RF / Wifi radio device nearby
I wonder if there is a way to detect if there is any RF/WiFi radio ON nearby?
I'm configuring an ESP8266 12E module in STATION MODE (not Access Point) to connect to a Wifi network (any Wifi network). ...
15
votes
3answers
4k views
Why does WiFi have a shorter range than LTE? [closed]
It seems confusing that my phone receives -87 dbm LTE signal and shows a full 4 bars with the speeds of
UPLOAD: 20Mbps
DOWNLOAD:13.6Mbps
But my WiFi is showing 1 bar at -89 dbm and I get ...
2
votes
0answers
278 views
Do I need to get a device certified by the FCC if it uses the ESP32/8266? [duplicate]
I plan on making a device that the user can control with their phone via a WiFi connection to an ESP8266 or ESP32. If I end up selling this device, will I need to get it certified?
The ESP32/8266 has ...
0
votes
1answer
129 views
How much input voltage is required to get 12v from LM2596?
I am trying to run WiFi router from a 12v lead acid ups battery.
To get a stable 12v output from the battery I used LM2596.
Problem is output is always 8.28v-8.50v. No matter how many times I spin ...
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votes
1answer
145 views
Is there a difference between the radio magnetic field your body senses, from downloading 1 kB data from Wi-Fi router compared to 1 GB of data? [closed]
Imagine you have a Wi-Fi router and you're downloading 1 kB of data, if your body is receiving any magnetic field or signal from the router, what would be the difference if the router was sending 1 kB ...
0
votes
3answers
142 views
PCB Trace Impedance Matching on microcontroller
I'm doing research for the best antenna for a 2.4 GHz connection from our device to a local router. The problem is that our device will have varying loads connected to the other pins of the micro ...
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votes
3answers
68 views
Use existing WiFi hardware as an RF receiver? [closed]
I have seen mine & many others' (Android) devices nowadays have WiFi hardware capable of connecting with 2.4Ghz & 5Ghz APs. Wanted to know if I could tweak the WiFi driver in the kernel source ...
3
votes
2answers
446 views
Wi-FI Antenna DC Blocking Capacitor
I have a 2.4GHz Wi-Fi design that uses an SMA connector connected to a dipole whip antenna. The issue is the SMA connector mounts to a metal chassis. This causes a potential issue in where someone ...
1
vote
1answer
88 views
wifi baseband access
I've got an unusual use case (optical communications) that would benefit from access to the wifi baseband signal before it is upconverted/modulated at 2.5Ghz. However most modern wifi chips combine ...
0
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2answers
155 views
What are the different antenna types used by various IEEE 802.11 standards?
I've been working on an assignment about the IEEE 802.11 standards and I've had some trouble with one aspect of a question. I need to explain the differences between various features of the different ...
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1answer
100 views
What type of module is this?
It's likely ESP8266-01, but when I look better there a bit more differences at its components. Also I think its pinout is different with a ESP8266-01. When I attach it to PCB I made for ESP8266-01 it ...
4
votes
1answer
440 views
How come esp8266 is able to generate 2.4 GHz wifi signals
I am wondering how it is possible to generate 2.4 GHz, if its core clock frequency is much lower than GHz scale.
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0answers
53 views
Microstrip for right-angled sma connector
I am designing a PCB with a wifi (2.4GHz) and LoRa (915MHz) modules and I need to provide right-angled through-hole SMA connectors for the antennas.
Initially I thought I had everything under control,...
0
votes
3answers
337 views
Bluetooth frequencies possible to Jam with Wifi routers?
Since Bluetooth operates at the 2.4 GHz with 1Mhz width and 79 channels would it be possible to Jam with a few 40 dollar routers at the 2.4 spectrum default I believe the channel width is 20MHz and ...
0
votes
1answer
40 views
Do wifi cards on client devices adjust tx strength depending on signal? [closed]
In trying to answer a question about wifi optimization in homes, one has to know whether a slightly lower signal on a client device (due to low TX setting on a router, for example) would normally be ...
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0answers
52 views
Connecting WIFI Module to RJ45 pins output of device
Extreme noob questions here. I have a Lantronix XPico 240 wifi module that I need to connect to the rj45 output pins of a device the device pins are clearly marked but I am not sure about which pins ...
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0answers
169 views
How can I measure the power given to a USB WiFi adapter's antenna in dBm or mW?
I have an Alfa AWUS036ACH USB WiFi adapter, and would like to know how much power is being given to the antennas (in dBm or mW). The Amazon link to it is here: https://www.amazon.com/Long-Range-Dual-...
1
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1answer
130 views
RF noise on different WiFi adapters
Background of my question:
I was checking the signal strength of wifi access points on my laptop in parallel with the internal Wi-Fi card and a nano usb wifi adapter connected to the same laptop. I ...
1
vote
1answer
98 views
Can a Wifi device be made to output a continuous 2.4 GHz wave?
I wanted to do some energy harvesting experiments involving wifi-frequency microwaves and wanted to see if there was a way to make a Wifi-enabled microcontroller devboard (something like the esp32) ...
0
votes
2answers
610 views
Am I unwise to power a low-draw cooling fan off my router's USB port?
tl;dr: I want to run a 120mm case fan (drawing 0.05A) off my router's USB port, and don't know whether to be concerned about running a DC motor off a sensitive box full of radios.
The CPU in my (ASUS ...
0
votes
1answer
44 views
WLAN speaker to speaker pairing
Is there a way to connect one speaker to another (I'm building my own ones) using WLAN. The idea was having a host speaker with a WLAN transmitter that could automatically transmit the music playing ...
4
votes
1answer
73 views
Safety with wireless MCUs with internal ROM
I read that the ESP32, as long as other MCUs like CC3200, they have an internal ROM not user accessible and usually not open source, used to initialize the device, if I am correct. This means that ...
