Questions on the implementation of Wi-Fi (802.11) hardware. Note shopping questions are off-topic.

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3answers
66 views

Calculate Wifi access point distance from reciever?

I have signal strength in dBm and frequency in MHz is there any way to find distance?? Or any alternate idea.
1
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0answers
38 views

Ubiquiti/UniFi PCB component identification and polarity question

I stupidly dropped a brand new Ubiquiti UniFi AP-LR wireless access point on the floor. The impact broke off a component (shown in the picture) from the PCB which is preventing the AP from working ...
1
vote
2answers
197 views

Is Bluetooth less susceptible to jamming than wifi?

I am developing a mobile peer to peer application that will probably be subjected to RF jamming, and I'm wondering if bluetooth is perhaps less susceptible to jamming than ad-hoc wifi. Bluetooth has ...
0
votes
0answers
5 views

Arduino stacking wifi and gsm shield [migrated]

I'm fairly new to this and I need some help before I buy anything... If I understand correctly I can buy an arduino, couple of shields and just stack them one onto another if they are compatible... ...
0
votes
0answers
12 views

Error building Arduino WiShield Flash example: 'dflash' was not declared in this scope [migrated]

I'm using WiShield library from: https://github.com/jcmuller/WiShield What is wrong with this library? The code: ...
20
votes
10answers
5k views

Why can't Wi-Fi run at 2.4 Gbit/s?

So Wi-Fi runs in the 2.4 GHz band, yeah (and the new ones 5 GHz)? Which means that every second, a Wi-Fi antenna outputs 2.4 billion square wave pulses, right? So I was wondering, why can't ...
0
votes
0answers
47 views

Where to start building this wifi video streaming circuit?

I am working on my own quadcopter and I would like to stream video from it to my computer. I know how to do it using Raspberry Pi and wifi dongle hooked to its usb port, but I don't want that solution ...
0
votes
0answers
23 views

RN 171 UDP Configuration not working?

I am trying to use a RN 171 module to send Data using UDP. The RN 171 is connected with a voltage regulator and this is connected to the laptop. I did all the configuration looking at the data sheet: ...
1
vote
1answer
120 views

Wifi on ATmega328P-AU

This is in continuation to my earlier post here: Wifi on Nano v3.0 ATmega328P-20AU Board What if I got a USB hub and connected a wifi USB dongle. Will that provide wifi functionality?
0
votes
1answer
56 views

SNR vs Signal Strength for digital throughput

I'm trying to compare two antennas, A and B for WiFi. A is showing: Signal Strength of -77dBm, but SNR of 9dB. B is showing: ...
0
votes
1answer
47 views

Is there any dependency between SNR and Link Speed for WiFi AP?

Today we use RSSI as indicator of AP quality. However even if you have rssi=-45dm it's not enough to say that AP WiFi guarantees you good BW. Because if many ...
0
votes
1answer
62 views

Instructions on building CMOS camera wifi video transmission [closed]

I am not sure this is the appropriate place to ask this kind of question, but I believe this is the best community to ask. I'd like to learn how to build my own circuit that would be capable of ...
-2
votes
3answers
147 views

What is the maximum height of a wifi signal in atmosphere? [closed]

What is the maximum height of a wifi signal in atmosphere? I am not mentioning range and also I dont want answers in milliWatt. I want to know answer in kilometers or meters.
1
vote
0answers
68 views

UART Wifi module setup

I recently bought this wifi module. Connected it to my pc and set it up according to the example provided. Thinking that it was just plug and play(as advertised) I hooked it up to my Arduino Uno, ...
0
votes
1answer
44 views

Wifi - How does channel difference between transmitter and receiver affect the signal/data?

When scanning a channel for wireless signals it is of course possible to pick up signals from surrounding channels. What I'm curious about (and forgive my n00b-ish-ness regarding the physics behind ...
-1
votes
1answer
95 views

Why wifi can not act like a server and client at the same time?

According to my experiments, any wifi card can (naturally) connect to a access point as a client and act as a server (most of them in ad-hoc mode). Why can not a wifi card behave as both a client ...
1
vote
1answer
51 views

Wifi - Determining the channel of a probe packet

How do applications such as Airodump-ng determine the channel of probe packets they receive? To my understanding, when the receiver is scanning channel 11 it can pick up packets all the way down to ...
0
votes
0answers
42 views

USB CDC RS-232 interface to Bluetooth or WiFi

I have a device that communicates with a computer via an USB CDC RS-232 interface. The thing is that I want to build an interface (on top of that USB interface) that enables the device to ...
2
votes
0answers
77 views

RSSI-Distance calculation help

Using this question as a guide I've been trying to calculate some distances based on RSSI values that I see in our lab. I filled in all the variables with actual data or approximations where necessary ...
2
votes
1answer
36 views

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 ...
4
votes
2answers
369 views

Battery life with a CC3000 WiFi beacon

We're experimenting with using a WiFi module as a battery driven beacon or RFID tag. The cheapest module out there with plenty of documentation (thank you Adafruit) is the Texas Instruments CC3000. ...
2
votes
1answer
35 views

Best method for trasmitting multiple video feeds at once via Bluetooth or WiFi?

If I want to transmit several video feeds via Bluetooth or WiFi what would be the best method to do so in order to save on bandwidth, increase speed, and maintain quality? I wanted to know what is ...
0
votes
1answer
45 views

How to compute the throughput varying the bandwidth

Let's say that I have two different wireless technologies, A and B. A has a bandwidth of BA MHz, B has a bandwidth of BB MHz. I can compute the capacity of (for instance A) with Shannon: ...
1
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0answers
62 views

Extending wifi range using Xbee

Is it practical to use Xbee for extending the wifi range of my home router? I thought of the following steps: Providing the router output to an Xbee transmitting unit. Transmit signals to the next ...
0
votes
2answers
79 views

How to simulate Wi-fi signal strength indoor environment?

I want to simulate Wi-fi signal strengths received by a mobile moving around in X m3 that contains N access points. I must take into account the effect of walls and if possible the effect of moving ...
1
vote
2answers
48 views

WiFi and collisions

since all WiFi operates in the same frequency which is 2.4 GHZ , if we set a certain number of access points in the same Region , for example , the maximum distance between them is 15 meters , could ...
4
votes
1answer
734 views

Permanent magnets near wifi device

Background I have a small circuit that consists of a microcontroller operating on 14Mhz and a wifi module. This circuit is enclosed in a small plastic box. I am considering gluing a few magnets on ...
2
votes
1answer
100 views

Closed circuit Wifi over coax?

If you connect an access point to (PCIe/USB) Wifi card over coax (i.e. no antennas) will it work? If it would work, what would the maximum cable length be? (This is just a thought experiment. I ...
1
vote
1answer
72 views

Can I estimate Wi-Fi's power transmission in function of the amount of data transmitted?

For a specific device connected to specific AP. Can I estimate the differences in radiation power (mWh) depending on the data transmitted (2KB/s vs 200KB/s)? If so, how?
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votes
1answer
88 views

Bluetooth dongles vs Wifi dongles

I see a lot of implementations on how to use a bluetooth usb dongle with arduino microcontroller. But I dont see even one single implementation to use with the wifi usb dongles. I get that the stack ...
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1answer
133 views

Arduino Uno - XBee communication

I have two Arduino UNO, two Xbee shield, and two Twi Xbee (type XB24). I am very new to xBee and my question is: Can I communicate each other via Wi-Fi ?
2
votes
0answers
58 views

How is CC3000 placed in Simple Configuration mode?

I've ordered a CC3000MODR and soldered it to a simple breakout board. In the First Time Configuration it mentions a Simple Configuration mode: The CC3000 is placed in Simple Configuration mode and ...
1
vote
1answer
97 views

To what extent can Gielis' so-called “Superformula” be used to improve the efficiency of WIFI antennas? [closed]

I am new to this Stack Exchange venue, so please don't shoot me if this question is not appropriate. This question was taken Math Stack Exchange. In 2003, the Belgian plant biotechnologist Johan ...
1
vote
1answer
306 views

Transmit and receive 433,92MHz signal from the smartphone [closed]

I would like to use my smartphone to send and receive signals from the devices that is working on the 433,92MHz. I assume that it's not possible to communicate directly with this device from the ...
1
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0answers
80 views

Shielded cable vs. unshielded in underwater environment

I know basic electromagnetic theory very well and understand why this works but I'm not sure about one thing regarding usage of coaxial (shielded) cable vs. unshielded (normal conductor) cable when ...
0
votes
1answer
63 views

Building a wireless door opener [closed]

In my parents house, the door is 'unlockable' via a switch. As long as the button is pressed, the door is unlocked. Since I often forget my keys, I thought to make a WLAN-Switch, which is controled ...
11
votes
1answer
260 views

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 ...
-3
votes
1answer
76 views

Do mobile phones lower their radiation if connected to WIFI [closed]

Suppose you have a phone you use for surfing, but the coverage is poor. As far as I know, that means it would have to increase its signal strength to max, quite possibly to a signal strength much ...
0
votes
2answers
78 views

Directional Wifi Antenna

I am looking for small size(preferably pcb mount) wifi antenna that is directional, more specifically half sphere coverage area. The product I build stays on the ground and I like utilized antenna ...
2
votes
2answers
149 views

Arduino sketch not running startup method

I am trying to use the WiFly shield ( http://www.sparkfun.com/commerce/product_info.php?products_id=9367) with Aduino Mega board. I am making modifications to the built in examples that ship with the ...
3
votes
1answer
71 views

WiFi wave cancellation

Let's assume there is an emitter and a reciver. As the emitter is usually omni-directional, the reciver may get one direct wave and some reflected waves. Why does not these waves influence each other ...
0
votes
1answer
486 views

How to connect a Printer WIFI module wires to an Arduino?

+ I’m a digital artist, found this HP printer on the street and wanted to use its components (motor etc.) on my projects. I was wondering if any of you know if I can use this WIFI module to ...
1
vote
3answers
356 views

Home Current Meter - is this a good solution?

I want to build a simple current meter to measure my power usage at home, and have the data sent to my blog's database. (I know there are similar solutions out there, but this project seems engaging ...
2
votes
2answers
425 views

Updated. Extending Range of a microstrip antenna with a SMA 2.4GHz Omni Direction 20db wifi antenna

Dear all I have the bellow A2DP bluetooth module which has a zigzag microstrip antenna. I want to extend the gain in the antenna with my 20db wifi antenna. I know as far as that I need to scrape the ...
0
votes
1answer
77 views

Which chip to use for automation using Wifi? [closed]

I am working on a project where I will be controlling a device using android mobile phone (WiFi as medium). Which is the chip at present in the market which is low cost and effective for my ...
1
vote
2answers
344 views

Using TLG10UA03 to send HTTP GET

I am using a TLG10UA03 WiFi interface together with my Arduino board. The intension is to send sensor data to a web server in order to publish it on a web site. I managed to run the TLG10UA03 as a ...
1
vote
1answer
106 views

How to modify a router's antenna? [closed]

I have tried to extend the antenna of my router in order to increase its range. I added a wire few cm long. There was no modification however in the range. The power (-db/m) was the same. Why is that? ...
0
votes
0answers
33 views

Accelemetor wifi module

I'm looking for a module that sends data from an accelerometer over WiFi. I looked around a bit and found this: Axivity-WAX3, but this was the only module I could find, and the site doesn't provide a ...
0
votes
1answer
72 views

Can a smartphone transmit over the 902-928MHz bands? [closed]

I came across a remote control that uses the 902-928MHz band. Can a smartphone transmit WiFi/Bluetooth over those frequencies? If yes, is there anything special about it? Thanks
1
vote
1answer
101 views

Is Atheros AR6102 all I need for my Wi-Fi SD card reader?

I was recently asked to create an iPhone app to allow the user to view, download and remove photos from an SD card. We can't use the card reader originally chosen, and for some reason I thought it ...