Using other than a wired connection to transfer signals or power. Includes optical and (ultra)sound, but most often refers to RF (radio-frequent). Distances can be as low as centimeters (e.g. RFID), there's no upper limit.
0
votes
0answers
14 views
SPI based WiFi support for SSV module DNP/9200
I am using Embedded SSV module DNP/9200 in my current project of an Ethernet gateway. I am using the TCP/IP stack by SSV with kernel 2.6. Now I want to support WiFi for this product using the ...
2
votes
2answers
122 views
+50
Building a wireless keyboard (preferably with a kit)
This is the project that spawned these earlier questions.
I'd like to create my own keyboard. Functionally it's going to be a keyboard, but visually it's going to bear more semblance to a joystick ...
0
votes
0answers
41 views
Erlang B telecom system (grade of service)
I am bit stuck with an answered question that I found online:
We have an Erlang B system where the total number of served call is 15.48 erlangs. The system contains 23 circuits. The incoming calls ...
2
votes
2answers
75 views
How to connect sensors to an Android device?
I need to build a device, which measures several parameters (body temperature, conductivity and pulse) and transmits them to an Android mobile device.
The system has following parts:
The sensors
...
-1
votes
0answers
44 views
Looking for a simple design for building a remotely controlled bell [closed]
I want to control a bell remotely. The purpose of this apparatus is to allow a translator to notify the speaker when to pause his speaking and when to resume.
The apparatus should be as simple, ...
2
votes
2answers
101 views
Wireless transmission of energy through a layer of non-conductive material
Is it possible to effectively transmit energy by electromagnetical induction?
I have a plate of nonconductive material (5-10 mm) and I would like to transfer electrical energy from circuit on one side ...
2
votes
2answers
196 views
Long Range RF communication
After playing with Arduino and different kind of sensors for my garden, now I'm starting a new project for my free time.
I want to work with RF communications because I need a long range device for ...
0
votes
1answer
92 views
Can the Signal from a Coaxial Cable be Transmitted via Bluetooth?
If so, can the coaxial signal be maintained without degradation (think inserting a transmitter in the middle of a coaxial connection to relay that signal wirelessly without actually interrupting the ...
-1
votes
0answers
44 views
Wake up a node wirelessly [closed]
I have an RF UART module device which is sleeping (master device). I can wake it via a timer and force it connect to any available slave-nodes and talk via RS232. However, I am wasting battery this ...
0
votes
1answer
54 views
why does signal attenuation caused by shadowing vary?
Given a RF sender and a receiver, suppose the obstacles between them are fixed, both their material and dielectric properties, does the signal attenuation caused by their shadowing vary over time? If ...
2
votes
0answers
47 views
why is shadow fading also called slow fading and large-scale fading?
I've encountered several similar claims regarding shadow fading on several books, and have some difficulty understanding them.
(1) Shadow fading is called slow fading because the duration of the fade ...
-4
votes
0answers
40 views
Wireless chip with long range and high transfer rate [closed]
I'm about to build an helicopter with which I'm going to include a camera. I wonder what kind of transmitter and receiver I need to transfer wirelessly the commands plus live video from the camera.
...
3
votes
2answers
58 views
What is wireless blocking immunity?
In a data sheet for a wireless transceiver I read
100 dB blocking immunity
what does this actually mean?
0
votes
0answers
30 views
Power consumption in wireless mesh network
I want to calculate the current consumption of a wireless mesh network. The network will use 6LoWPAN in a fire alarm application. I want to sense fire or smoke and have response time of 10s. Also, the ...
0
votes
0answers
33 views
Double dispersive channel with jakes model in matlab
I need to simulate a double dispersive channel with jakes model in matlab. I don't know how to choose the elements of the channel matrix. Do I have to choose them with a specific mean and variance?
...
-4
votes
0answers
74 views
Advice needed: Develop a bluetooth device at the size of finger ring [closed]
I have a small requirement. I like to amplify the microphone signal of a smartphone (android/iphone/windows phone) using a bluetooth device that can be worn on finger as ring. The idea is not to loose ...
3
votes
2answers
91 views
“Wireless” USB cable, via RF / 3G
I'm looking into the feasibility of a project to develop a USB-over-RF device for physical penetration testing engagements. The idea is that our tester could connect a device to a USB port on a ...
1
vote
1answer
27 views
Power delay profile and broadband bus
I came across the following solved question, but I have trouble understanding part of the solution. If anyone could shed some light into this I would be really grateful since this problem has been ...
0
votes
0answers
89 views
RF Link with APC220 between two PIC16F877's
I am attempting to communicate through a RF link between two PIC16F877's using APC220 Radio Transients. When the PIC UART's are connected with wires between TX and RX they communicate just fine, but ...
0
votes
1answer
73 views
Data from an arduino to be transferred to COSM through wireless internet
I am trying to collect data from sensors through an arduino and send it over to the COSM server. My main problem is that the arduino will be in an environment where it will be impossible for me to ...
-3
votes
2answers
93 views
Free space model (wireless communications)
The received power at a given distance = 1km is 1nW .
Find the received power at a distance of 5km from the same transmitter , using the Free Space Model.
Suppose that frequency is 1800Mhz, ...
2
votes
2answers
80 views
Communication between embdedded system and Mobile phone
I am software developer and new to the embedded systems.
I need to use a wireless communication method to send/receive data from embedded system and a mobile smart phone (Android - iPhone).
My target ...
0
votes
0answers
48 views
Transmitter/receiver pair for on/off signal
For a project I have been searching for a transmitter/receiver pair where the transmitter can be paired with a device, and when the device gives the transmitter a simple on/off signal the transmitter ...
13
votes
1answer
458 views
How to build the circuit of a small wireless camera?
I did a good search, but I want to know if anyone has other idea(s).
To create a wireless camera, I need:
The camera circuit
A wireless transmitter
A battery
The receiver is not a problem, it can ...
-1
votes
1answer
60 views
XBee Design and UART characteristics
I want to connect XBee to PC , does xbee send serial data or need UART to do that ?
2
votes
3answers
81 views
Wireless communications for distance estimation (RFID perhaps?)
What I want to do it is measure the distance between two points/ devices which are constantly moving apart or together. The value for distance isn't really required I'd just be looking to have an ...
2
votes
2answers
67 views
Realizing an flexible, but fault tolerant, infrared communication chain
The task fell on me to realize a wireless, daisy chained communication system. The communication must be wireless, esp. via infrared diodes. The end of the chain is connected to a PC (wired).
The ...
0
votes
1answer
109 views
Problem connecting UART Wifi Module to PC
As refereed to my old question ( Connect UART WiFi module to PC ) which has been solved that days, I have a UART Wifi module ( this one ) and unfortunately I have problem again ! The point is, this ...
0
votes
3answers
113 views
A device that wirelessly, securely posts to a server in response to door opening: off the shelf or custom-make?
I am looking for an off the shelf component for a project I am currently working on. Due to the nature of the project I cannot go into much detail about the project itself, only give a high level ...
0
votes
1answer
63 views
Noise on Bluetooth Low Energy module power supply
I have a bluetooth low energy module (BLE112), which I'm trying to use on my PCB. When I supply JUST the module with a coin cell battery, it works great and I can see it advertising on my wireless ...
4
votes
2answers
68 views
Xbee to act as wireless i/o extension
I want to have an arduino with an xbee (call it xbee1) connected to it and another wireless xbee (call it xbee2) communicating with xbee1. Then I would have DIO1 on xbee2 acting as a digital input and ...
0
votes
0answers
45 views
I want a gsm module that could be attached with a mic and could transmit the voice to my mobile .. is that possible?
I'm making a project so that I place it somewhere and when I call it I could hear what's going there .. so I want a gsm module that could be attached with a mic and could transmit the voice to my ...
1
vote
1answer
293 views
Broadcast audio to multiple receivers via Bluetooth
I want to be able to connect multiple Bluetooth devices to a Bluetooth transmitter, and then stream audio from a portable MP3 player, via Bluetooth, to all of the connected Bluetooth receivers. Is ...
3
votes
2answers
125 views
Designing a Low Power wireless temperature transmitter
I'm going to work on a project in which I need to take your experienced into consideration to which path should I go to.
I need to design a wireless circuit at max size 5*2CM, that has a thermostat ...
-5
votes
1answer
66 views
Receiving videos via wifi [closed]
I'm working on a electrical board that should receive videos from a server via WIFI. The size of the video is around 100 MB..it will be stored afterwards into an SD card ...so my question is what WIFI ...
0
votes
0answers
158 views
Transmission via RF433Hz Transmitter/Receiver pair failing AVR
I am trying to send data wirelessly through a RF433Hz receiver/transmitter pair, but nothing seems to want to work.I want to the transmitter to continuously send a number (0x81) to the receiver when I ...
2
votes
1answer
81 views
Detecting if two objects are close to each other
I am an electronics beginner but want to make two devices that can detect if they are near each other.
So if the devices enter a radius of less than 2 meters of each other they will both trigger an ...
4
votes
2answers
160 views
Inexpensive medium-range wireless for small projects
I'm building a few sensor projects that will need to pass status messages wirelessly. The required range is standard household distances; 30 to 100 meters indoors, through walls, etc.
The XBee ...
5
votes
1answer
231 views
Why is 433 MHz still used?
The new RF frequencies are 868 MHz for Europe and 915 MHz for the US. I heard 433 MHz is barely regulated, read: it's chaos. Then why are 433 MHz RF modules still used? Are they cheaper to produce?
-2
votes
2answers
160 views
Ultra low power Micro Wireless Audio Transmitter/Reciever [closed]
I'm am trying to send a signal from a device to a receiver. The signal would need to travel through walls/an enclosed area up to at least 150'. The signal would have to be powered by two AAA ...
2
votes
1answer
117 views
Low-power wireless module strategy
I'm designing low-power sensor modules which will be spread over a reasonably small area. The modules are all battery powered and should operate for a decently long time without having to ...
2
votes
1answer
963 views
How can I send video from my Arduino camera module video to my Android screen?
I'm trying to connect a camera module to my Arduino Mega, connect my Mega to my Android phone (throught BlueTooth or other), and send the live view of the camera to the mobile phone.
I saw a video ...
-3
votes
2answers
76 views
How to send information over large number of client?
I have one master which needs to send information to lots of slave device ~1000 which needs to receive same information.
As I need to power all of the slave device, I was thinking of using same wire ...
-1
votes
1answer
105 views
Too cold for transmission? [closed]
I've got a weather station which only intermittently sends data. The technical support claims it's because the receiver must be in a room above 15C.
It has got batteries, but even if I connect it to ...
1
vote
0answers
97 views
Receive signal from transmitter with PIC
I have been trying to build a simple wireless setup using the parts enumerated in this post, except I am using a 16f88 pic. Like the poster in the forum I am able to send things from the PIC to the ...
4
votes
2answers
76 views
PICAXE and RFA001
I have two 40x2 with a RFA001.
I whant to send 1 if the I push the pusher and high a led to know if it recived the code.
It seems that doesn't work. It's correct?
Transmitter:
...
-1
votes
1answer
79 views
How is (non-interfering) data communication possible over the tv spectrum? What is the technology used?
I've heard that FCC-US (Federal Communication Commission - United States) has approved the free usage of TV spectrum for wireless communication. How is it possible to enable such data communication ...
2
votes
1answer
112 views
Analog vs digital wireless newbie questions
As i try to understand the real difference between analog wireless and Digital wireless i'm asking some questions :
As far as i know digital means more accuracy of data, but require larger bandwith to ...
0
votes
1answer
320 views
Boosting wifi antenna with aluminum foil: ideal placement/size?
On more than one occasion I have successfully (and significantly) improved the wifi signal a desktop computer was getting simply by taking a flat sheet of aluminum foil and curving it into a ...
0
votes
1answer
128 views
What kind of Transmitter and receiver would I need? [closed]
I am trying to figure out exactly what it is I am needing, I am wanting to protect my chickens from my dog killing them! I want to place a small transmitter onto a leg band which will be placed ...
