Exchange of information between devices. Communication can be wired or wireless.

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32 views

Check me on this modulation question?

I need to check my answers for parts (a) and (c); a) I got q(t) = p(t)cos(5pit) c) i got y(t) as a rectangle with amplitude 1 from -pi to pi. So, y(t) = 1/8 f(t) Am I correct for both parts;
3
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1answer
47 views

AVR - ATmega16 - Timer config

Trying to figure out the timer setup in Atmel Studio 6 for an ATmega16 microcontroller. And I just don't get it. I am trying to create a TickCount similar to GetTickCount() Retrieves the number of ...
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1answer
52 views

Bandwidth of CW modulation (morse code)? [duplicate]

How can I relate the bandwidth required by a morse code signal over RF to: the length of a dash, and the length of a dot the time between dots and dashes the speed of keying? Are all applicable to ...
2
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0answers
66 views

What is bit-true implementation

What is bit-true implementation (with an example if possible)? I was reading a paper and it was stated "a bit-true implementation of the algorithm on a FPGA was performed." So what exactly is ...
2
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2answers
53 views

Signal rate, data rate and bandwidth in digital signals

I'm trying to understand the concept of signal rate and the relation between signal (baud) rate and bandwidth of digital signals from a book about data communication. First, the book distinguishes ...
3
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2answers
402 views

Bandwidth for a single tone

If I am using a channel only for morse code (CW), with one frequency and interruptions for dots and dashes, is the necessary bandwidth of the channel twice the audio frequency of the tone used for CW? ...
3
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1answer
60 views

Bluetooth low energy communication

I was wondering if it is possible to communicate between 2 BLE devices when one is placed inside the car and another placed outside the car. Can BLE communicate in such a scenario? For example, I ...
0
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2answers
29 views

the response of wireless channel to an input

I am reading the wireless of David Tse. In the 2nd chapter of this book there is a discussion about the response of the channel due to an input. It has said that since the channel is linear its output ...
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1answer
62 views

What's the maximum CAN bus frame (message) rate at 125 kbit/s?

My CAN bus is running at 125 kbit/s and is using extended frame format exclusively. I would like to know what's the maximum rate of CAN frame I can send out. Suppose the data length is always ...
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2answers
69 views

Explain Rayleigh Fading in plain English

For a couple of days I am trying to understand the Rayleigh Fading model, but I am failing to. I look at various articles and tutorials online, everything goes fine up to a points, but then a lot of ...
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0answers
50 views

Read and write FPGA registers via USB or Ethernet

I'm working on an FPGA project on an Atlys Spartan 6 board. I'm programming it in VHDL. I have two 32 bit registers, one for output, the other for input. I need to be able to, respectively, read and ...
2
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2answers
74 views

GPRS data call using GSM/GPRS modem (Siemens TC35 and/or MC35)

I'm developing a data aquisition module, that amongst other things, it have to comunicate through GSM/GPRS module, since it will be a mobile application. I can connect to the module and send sms's ...
1
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1answer
39 views

What happen if 0 and 1 are transmitted simultaneously with BPSK?

I'm just curious that what happen if 0 and 1 are transmitted simultaneously from different source nodes to an equidistant destination node with BPSK? Assuming perfect signal shaping, synchronization ...
0
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1answer
45 views

frequency allocation for telecommunication companies

For a high bit rate in data communication we need a high bandwidth. Suppose there are hundreds of carriers in a particular region and they are all allocated microwave frequencies. Minimum spacing ...
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0answers
33 views

If a jitter comes, how symbols of QAM is impacted

Thank you. skillful everyone. Owing to you, I have been able to studied little by little. Let me say thank you very much. Well, if a jitter or a wander comes, how are the each symbol of I-Q coordinate ...
1
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1answer
56 views

Quantization levels and SNR

Im' trying to build a big picture of telecommunication and i'm stuck in a topic, related to digital communication. But the problem is that i can't go too deep into the topic because it is imensely ...
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3answers
135 views

How do you achieve an efficiency of more than 1 bit per Hertz?

I believe this is also known as spectral efficiency - apparently it's possible for us to transmit more than one bit per Hertz. But to my layman mind I imagine a Hertz being only capable of ...
1
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1answer
31 views

Real Time Data Capture System

I would like to build a system which could capture an analogue waveform data in real time. For the basic data acquisition system I can use an ADC to digitise an analogue waveform and store this in a ...
2
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1answer
42 views

Wireless telecom system (cellular with Erlang and spectral efficiency)

We have a spectrum of 20MHz that we will use on a wireless cellular system, which requires 50kHz per channel. The system is using cluster size K = 4 and the radius of every cell is R = 1 km. a) ...
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0answers
25 views

Calculating Eb/No for a desired Pe for a matched filter

can someone verify that I am doing this right. I have been given the question: In most applications, communication systems are designed to have a Pe of 3E-5 or less. Find the minimum Eb/No required ...
1
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1answer
64 views

Calculating the output power from an Amplifier

This is not based on any particular hardware. I am trying to understand the theory behind it by doing tutorial questions from my uni, I have completed the question but don't understand the approach ...
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1answer
120 views

What is the 'best' way of communicating with small microcontrollers/devices?

var best = "simple & cheap"; I have a server in my apartment that I have an XBEE hooked up to. I use it to communicate with another XBEE plugged into an Arduino. I am trying to hook up many ...
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0answers
52 views

Definition of “hot” resistor when calculating RMS thermal voltage?

I am calculating the RMS thermal noise voltage of a "hot" resistor of a tutorial sheet for uni. I have used the standard Johnson–Nyquist formulas, but the answer sheet does not include the entire ...
1
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1answer
48 views

Xbee configuration with X-CTU on linux

I'm trying to configure an XBee with the X-CTU tool using Wine. I followed the steps given in this tutorial. I plug the USB in and check the kernel logs to see on which serial devices it has been ...
0
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2answers
51 views

How does Signal-Noise-Ratio related to receiver power

If I have the instaneous Signal-Noise-Ratio (of the receiver), but no other information, and I am interested in the instaneous \$\mathbf{Power_{received}}\$, is there any relationship between these ...
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0answers
49 views

How to calculate Input backoff per carrier of a satellite

I was trying to calculate the sizing of SSPA in my satcom network where input backoff per carrier is required to calculate Power flux density. My current network configuration in C band is Total ...
0
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1answer
50 views

Cell in Cellular communication

When they talk about the "cell" in cellular communication, they often refer to the shape of hexagon. If I am correct, this is probably the coverage area of the transmission base tower. SHouldn't be ...
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3answers
86 views

Long distance communication

I am looking for a cheap single wired solution to transfer data of some sensors connected to a uC over a distance of 1 KM from a control room on UART. The data is of 16 bytes, no high speed ...
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2answers
126 views

Why is propagation delay of ethernet cables unaffected by cable length?

I did some searching on how propagation delay in ethernet cables is affected by the cable length. The answer seems to be that the delay is negligible until the cable length reaches a kind of threshold ...
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2answers
77 views

660 Mbits per second photo-diode amplifier on 3.3V rail

I've got a 10mW laser diode that can transmit at 660 Mbits per second, I've got the laser driver circuit that can do this, I've got a photodiode from Hamamatsu that looks good for this speed (-3 dB ~1 ...
0
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1answer
89 views

I get back wrong chars from bluetooth module (uart)

I would like to communicate between my atmega8 controller and PC via an HC-06 bluetooth module. I should get back the same char that I send but I get some wrong characters. The bluetooth module uses ...
0
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1answer
124 views

Max Distance for 5V serial communications

I have an application where two different microcontrollers need to communicate. I was thinking that for simplicity, just use 5V instead of converting to RS232 levels. What in good practice would the ...
0
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1answer
42 views

Definition of link gain for an optical system

Is the link gain the gain of the whole system or just over the diode? And why does the threshold current of a diode laser have no impact on link gain whereas increases in slope efficiency have a major ...
0
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1answer
71 views

Designing a simple energy-efficient communication protocol?

What is the required background knowledge in order to be able to understand and work on the design of a communication protocol which has to be robust, simple and capable of coping with short contact ...
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0answers
23 views

Which Communication technology to use? [duplicate]

I want to create a network of transreceivers which are able to send data to one base station these transreceivers should also have support unique ID the range should be around 5KM power no issue but ...
17
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3answers
2k views

Difference between UART and RS232?

Most of the time RS232 and UART come together in serial communication theories. Are they both the same? From my readings I concluded UART is a hardware form of RS232 protocol. Am I correct?
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3answers
112 views

How would I software-decode this 260KHz serial stream?

I've probed this serial stream coming out of a scoreboard controller and it seems like a proprietary protocol. How would I go about trying to software-decode this? The start bit is 7.8us long. All ...
0
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1answer
38 views

What determines the communication speed? is it the physical link's speed or the communication card speed?

Two IEDs (Intelligent Electronic Device),an electronic relay and a gateway, are connected with Modbus RTU protocol over RS232. In the relay's manual it states that a speed of 9200 bauds can be ...
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2answers
94 views

Transmitting data over light with USB

I'm working on a project that uses light as a medium for data transmission. I would like to achieve about 2-3 MB/s. It suppose to virtually behave like any LAN cable. I would want to know if it is ...
0
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1answer
38 views

Fourier transform of the components of bandpass signals

I'm referring to a book called Communication Systems by Simon Haykin, 3rd Ed. It says that a band-pass signal \$s(t)\$ with mid-band frequency \$f_c\$ and bandwidth \$2W\$ can be represented as ...
0
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1answer
70 views

How do I tackle phone-microcontroller BlueTooth communication?

I have this bluetooth module I bought on RS a while back, and I was pretty keen to set it up with an STM32L152 development board I have handy. The only thing is, I'm not really sure what steps I have ...
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0answers
22 views

J-Link bad data transfer for STM32F40x ARM CPU

I am programming a modem driver for an STM32F40x ARM CPU http://www.st.com/web/en/resource/technical/document/datasheet/DM00037051.pdf. I am using a Segger J-link to download the program. ...
1
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1answer
100 views

MCU selection for developing a baby monitor

I'm developing a project which involves a device (stationary, connected to mains) making some simple calculations and processing, and then sending an alarm (a simple message to trigger a vibration ...
0
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1answer
58 views

Read / write hardwares values for FSUIPC (module for FS)

I'm building an auto-pilot module for FSX (flight simulator) with push buttons and rotary encoders. My micro is one ATmega88. My question is how I do the communication with FSUIPC (software to read ...
2
votes
1answer
122 views

CAN connection help needed

I bought the IAR Kickstarter kit to work with the SM470R1B1M-HT (Texas Instruments) microcontroller. I would like to implement CAN communication between the microcontroller and a PC. I need to send ...
0
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0answers
89 views

Which serial protocol or encoding scheme does this scoreboard use?

I am trying to decode a signal stream coming from a Nevco scoreboard controller: Packets like this are sent every ~2.7 ms. I suspect it is some sort of UART signal because it is on the RX line of ...
1
vote
1answer
157 views

Communication between FPGA and OMAP 3530 using GPMC

I am working on a project which requires communication of data between Xilinx Spartan 6 FPGA (XC6SLX45T-2FGG484) and OMAP 3530, I have a ULK dev board on which The 32Kx8 (256Kbits) serial ...
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1answer
109 views

Which modulation does radio walkie talkie work on? [closed]

On which radio band does walkie talkie work on? Is it amplitude modification, frequency modulation, or short way modulation?
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3answers
138 views

Is the CAN bus protocol a master and slave protocol?

I am investigating if the CAN bus will work for the projects I am building at the moment. I want to create a bunch of input/output controllers that will accept/buffer commands, execute them and then ...
10
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2answers
613 views

How much power do I need to transmit a radio signal through a solid ice crust 100 km thick?

Imagine I put a floating probe inside the subglacial ocean of Encelado or Europa: how much power should my radio have to be able to communicate from external surface with the probe? Or, in different ...