Questions tagged [802.11]
IEEE 802.11 is a set of media access control (MAC) and physical layer (PHY) specifications for implementing wireless local area network (WLAN) computer communication in the 2.4, 3.6, 5 and 60 GHz frequency bands. Most knows are IEEE 802.11b, IEEE 802.11g, IEEE 802.11n.
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How to make an 802.11b/g conducted power measurement, getting different results
I am an engineering co-op tasked with measuring the output power of an avionics WiFi unit. I want to measure the maximum conducted power at the coax port to then calculate max EIRP.
The challenge is ...
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What is used to determine the length of a Wi-Fi SSID and password for the 802.11 standard?
I am finding a lot of conflicting information with regards to the data that can be contained in the SSID and passwords of a WiFi network.
I would like to conform to the 802.11 standard and not only ...
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802.11 Wi-Fi Module that allows direct access to PHY layer [closed]
I am looking for a Wi-Fi RF chip that allows me to bypass the MAC layer. I want to simply select a modulation, frequency and tx power, then add a simple payload and transmit (I am aware there more ...
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Mechanism/purpose of the NAV and its relation to the exposed node problem in 802.11
802.11 uses csma/ca as the mac protocol.
Every station senses the medium, if something is being sent, then they will set their NAV to the duration ID from the packet being sent weather RTS, CTS, DATA, ...
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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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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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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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ESP32 using BLE but not WLAN
I want to build a little gadget which must use BLE to communicate with a smartphone, but should run for at least 24h using a 500mAh battery. So I think to achieve this, I should be able to switch off ...
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What is the length of one symbol sent through WiFI?
Having a WiFi emitter sending a frame, how much time does each symbol take? And therefore, what distance do they spread over?
This depends on the Modulation Coding Scheme. I would like to know which ...
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Why does probe request signal varies significantly in the same second?
I’m doing a crowdsensing experiment and I'm capturing a handful of probe requests packets in my Raspberry Pi 3B in my vehicle. To test them, I capture a handful of packets of my own phone. Whenever I ...
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Time Synchronization between stations over WIFI 802.11n
I'm working on a wireless (2.4Ghz WiFi 11n) project where multiple nodes (ESP32) send very small data to the AP, something like 40 bytes every minute or so. I need to maintain an accurate coordinated ...
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Maximum transmit power allowed for 802.11g
I'm learning about the 802.11 regs. In a book I'm using, "CCNA Wireless 200-355 Official Cert Guide (Certification Guide) 1st Edition
by, David Hucaby (Author). Page 53", it has the following clause ...
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Can two 802.11n devices communicate via a coaxial cable?
Coaxial cables with RP-SMA connectors are often used as extensions for external antennas / with software defined radios.
What would happen if I were to connect two access points (wifi chips, via ...
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OFDM symbol period and minimum burst durations
I have been reading about cognitive radio using OFDM and literature on technologies like LTE and 802.11 variants. A useful value in the system analysis is the OFDM symbol period \$T_u\$.
Is it ...
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What is the full form of PAR in terms of IEEE documents?
Every IEEE standard has a PAR document, like I found CSD to be Criteria for Standards Development. PAR is a similar document which is approved before working on a standard. Apologies if the question ...
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Need help with understanding the pros and cons of geometric and stochastic based channel models. Which one s preferred under which conditions?
https://www.adv-radio-sci.net/9/165/2011/ars-9-165-2011.pdf
https://ieeexplore.ieee.org/document/7794648
https://pdfs.semanticscholar.org/c301/8463116117ea64f69638e15aa78fe9e84093.pdf
https://www....
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IEEE 802.11b bandwidth and data rates
I am self-studying on how 802.11b bandwidth and data rates are calculated, primarily those of 1 and 2 Mbps. These are my understandings, please correct them if they are wrong. Please keep in mind I am ...
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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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Development of proprietary WiFi protocol
I would like to do some customizations to IEEE 802.11 MAC layer protocol and implement it on hardware. I searched rigorously but I could not find any chipset with 802.11 PHY (RF + baseband chipset) ...
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speed of 802.11n using 2 antennas
My Wifi router claims to provide bit rate upto 300Mbps and support 802.11 b/g/n. But 802.11n standard requires using 4 streams(4x4 MIMO technique) using 4 different antennas. Mine has only 2 antennas. ...
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Why does 802.11 use the same modulation for each subcarrier?
In Wireless Communications, Dr. Molisch writes that the 802.11 standard "does not foresee truly adaptive modulation in the sense that the modulation alphabet can differ from subcarrier to subcarrier."
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disabling CSMA/CA protocol in esp8266 or any other wifi ic
Is there any way to disable or bypass CSMA/CA in esp8266? I don't want my packets to wait for channel to be clear. I want them to be transmitted at predefined time. If it is not possible to completely ...
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Accessing MAC Layer information
In the 802.11 MAC, there are several parameters such as the RTS/CTS threshold, Binary Backoff timers and NAV (Network Allocation Vector) timers to name a few.
Is it possible to obtain information ...
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Is it important to consider channel bandwidth of the signal to measure cable path loss for RF testing?
I am performing some RF tests for 802.11 and measuring path loss of the RF test setup, it has a mix of PSK & OFDM signals. I see the norm is to use a Continuous Wave signal to perform RF path loss,...
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Packet Loss in CSMA/CA
I am simulating a dense network in NS-3, with around 200 nodes each sending 1MB of data to a single AP/router. Although I have set the CCA threshold to a very low value (so that all 201 nodes are ...
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How is it decided what modulation is used during an 802.11 communication?
I understand, that 802.11x protocolls can use different type of modulations. BPSK, QPSK, 16-QAM, 64-QAM... I also understand that the used modulation depends on the quality of the channel, I guess on ...
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In 802.11 (CSMA/CA), does a higher data rate imply more number of collisions?
In a wireless environment working with the 802.11 protocol suite, where the MAC protocol is based on CSMA-CA (collision avoidance), a higher data rate would mean that data is sent more quickly, which ...
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How does data rate change when Wifi channels overlap?
Let's say there are two wifi access points close to each other, both uses the same channel and the same protocol, with the maximal theoretical data rate of 54Mbit/s. I understand that in case both of ...
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Lowest latency out of the 802.11 Wi-Fi standards
I'm making a project using an Arduino and an ESP8266 module running the esp-link firmware - which gives me the ability to use MQTT for controlling the Arduino. I'd looked at something like an XBee ...
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Does Bluetooth 4.0 penetrate concretes?
I am working on an application where I want to make wireless communication between two embedded devices. The core problem here is that I want to put one of these devices in a room that's totally built ...
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Locating the Origin of 2.4GHz RF Transmissions
Is it possible? How would it work?
Consider IEEE 802.11 (aka.Wi-Fi); for instance.
There's such an incredible amount of devices out there, measuring and reporting WLAN AP signal strength (RSSI, RCPI, ...
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Does Bluetooth 4 or 802.11b/g/n penetrate through walls better?
I'm thinking of building a signal beacon designed to be used indoors. The transfer speed isn't critical but range and penetrative ability are. Does anyone know if Bluetooth 4 or 802.11b/g/n might be ...
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How do you implement wifi with a front-end chip?
I was looking around for a solution to hook up an application with an MCU to a wifi network. I'm basically looking for a chip that can talk to my MCU via an interface like I2C or SPI and is able to ...
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Can you implement WLAN on a ZigBee chip?
I've spent my afternoon browsing around the web looking for a microcontroller that has integrated WLAN (802.11), but I haven't managed to find any on the market. There are lots of cheap ...
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Why 802.11g has a maximum throughput of 54mbps?
Can anyone explain why the maximum throughput of the IEEE 802.11g standard has a maximum throughput of 54mbps I can not find that. I would like to know how do you get this 54 taking into account the ...
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802.11 Channel Use Regs
With a 5.8 Ghz WLAN device, operating in the upper UNIII band of 5745-5825 MHz...
Is it required that, if the device is using a standard 20 MHz-wide 802.11 channel, that you can only be centered on ...
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Does bluetooth implement the 802.11 wireless standard?
I've read that the Bluetooth standard is IEEE 802.15, but it is implemented with IEEE 802.11. Is this true? Do they interfere with each other?
What standard is Bluetooth considered to use?
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Is there a wifi chip on this board? [closed]
I have a Sony QX10 camera, with comes with built-in wifi. I want to to connect wired ethernet to it. I was hoping I could find a wifi chip inside the camera, and solder to where the ethernet traces go ...
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IEEE 802.11 standard on channels
Could someone please help me find (page#) where in the IEEE 802.11 standard it directly says that Access Points are responsible for choosing the channel/frequency to be used and not clients. I know it'...
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Why does the 802.11 wifi spec allow for 11 channels?
The general wisdom is that it is better to only ever use channels 1, 6, and 11 as they are the only three non-overlapping channels for 2.4ghz wifi (in the US), and two adjacent networks on the same ...
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MIMO with directional antennas
In the context of a competition, I need to set up a wireless link between a base station and a mobile target.
The mobile target:
-> will always be within the same 180 degree cone from the base ...
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Why does an 802.3 (Ethernet) frame have 2 MAC address fields while a 802.11 Frame has 4?
I'm trying to understand the IEEE frames. 802.11 frames have four MAC address fields: The source (original creator of the frame), destination (ultimate destination of the frame), transmitter (the last ...
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WiFi antenna 1T1R mode
I have a question related to 802.11n wi-fi antenna. What actually do we mean by 1T1R mode for Wi-Fi?
As per wiki, the same channel is used for Tx & Rx:
http://en.wikipedia.org/wiki/MIMO
http://...
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Adding Wifi+ Micro-controller to a device in an economical but production-able way
Is it possible to reliably and economically add Wifi+ Micro-controller(for very simple logic and GPIO) to a non-moving device? I see some wifi soc in the market too. are these a viable options? I am ...
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