Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [wireless]

Using other than a wired connection to transfer signals or power. Includes optical and (ultra)sound, but most often refers to RF (Radio Frequency). Distances can be as low as centimeters (e.g. RFID); there's no upper limit.

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How does wireless communication work?

This is a problem that's always baffled me a bit. How does high frequency (more than 100MHz anyway) wireless communication actually work? I understand that it has an antennae and for receiving it amplifies it and checks for a logical 1 or 0 and…
Earlz
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Can power actually be sent into the ionosphere for transmission?

I always was amazed by a great man named Tesla. I have looked everywhere to see if I could get the truth of what he actually did but I just don't know what to believe. I don't what to trust, what to take as just a "false conspiracy" and how to get…
skyler
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LTE UE REPORTED CQI - Defined by RS-SINR or by Transport Block Mapping?

First than anything, let me assure you I am fully aware that no one REALLY knows HOW UE manufacturers specifically implement the CQI reports sent on the UL, but there should certainly be a better engineering answer to my question. This is…
Lamberto
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How does k-nearest neighbor apply to wireless network positioning?

I'm trying to gain some insight into the variety of positioning algorithms for wireless networks. Apparently there are three categories of algorithms: distance estimation, scene analysis and proximity. As far as I understand, distance estimation…
Pieter
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High density wireless -- pros and cons of different wireless systems?

I am working on an arduino-based robot that might be used in a classroom environment, in which case there could be forty of them in a single room. If I want them to be wireless, what problems might arise that I wouldn't find with just a few systems…
orangenarwhals
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Short Range Wireless Protocol History

When did numerous short-range wireless protocols start showing up? I know Bluetooth was first invented by Ericsson in 1994 from reading up resources on the Internet. Thanks in advance.
stanigator
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Wireless Communication Ideas

Im going to be working on a project where I will need 2 nodes and one base station. To communicate with each other. I am going to be using an Atmel AVR for the processing on the base station. I have thought about playing with the Atmel raven…
Dean
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how to tag and find objects using wireless technology

I am not sure if this is the right forum for this question, If not please help me move it to the right place :) Question: I have 10-20 items like tables / books in a room and I want to put a small self powered chip on them (solar / battery) that i…
Vivek
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why use OFDM, not PSK/QAM for high speed data transfer

Why is it harder to modulate/demodulate the PSK signals on high baseband frequencies(1 Ghz for instance) with high sample rates than modulate a multicarrier OFDM signal - do IFFT, FFT to receive/transmit.
Sergey Kulik
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How many concurrent senders can CDMA support for a code length of n?

I understand how CDMA works (kind of). I'm just not sure how to go about figuring out how many orthogonal signals can be produced from a code length of a given number.
user922467
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Wireless power transfer through stainless steel

The SS in question is 316, and is only weakly magnetic. Does anyone know whether this is possible?
Dirk Bruere
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Is there any chip which supports 802.11 along with 802.15.4

I am looking for a chip which supports both 802.11 along with 802.15.4 over a simple SPI interface. Does anyone know of any such chip?. Also , is there anyway I can use the existing 802.11 chips on my laptop to actually read the data on the 802.15.4…
user2714712
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MIMO system model

We consider a wireless communication system, where there is only Line Of Sight path between the MIMO transmitter and the MIMO receiver. MIMO antennas are used here to increase the directivity of the transmitter and receiver and create a pencil beam…
wHlearns
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Options to send an ID signal

I want to make a device that, with a press of a button, will send an ID signal, wirelessly, to some other device. It has to have: 10m range (~30 feet) <2ms response time (from the press of the button to the reader's response) ID size more than…
Eelvex
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How does a wireless device alert the master to its presence without interfering?

My understanding is that wireless devices, such as a cell phone, must speak to a master device like a cell tower and the cell tower will then arbitrate who gets to talk and when. Maybe my understanding is wrong, but assuming it is right, how do the…
CodeMonkey
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