Questions tagged [optical-fibre]

A flexible, transparent, fine fibre made of extruded silica to function as a wave guide to transmitting signals through light

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25
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3answers
7k views

How is 255 Tbit/s processed in optical fiber communication?

I have never understood how the new record breaking data transfer speeds are achieved in terms of converting from/to electrical and optical signals. Suppose we have 255 Tbits of data and we want to ...
12
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5answers
5k views

Why does a longer fiber optic cable result in lower attenuation?

I just carried out an experiment in my college to study the attenuation of fibre optic cable versus length and type of cable. This experiment was carried out with an LED light source and a power ...
12
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4answers
12k views

What is the advantage of optical TOSLINK over RCA coaxial cable?

A popular standard for the transmission of digital audio between audio devices has been the AES3 standard (also known as S/PDIF). The standard sends stereo PCM audio and of often found in consumer ...
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6answers
6k views

Does Fibre Optic Cabling have any potential for noise?

After Google searching "Do Fibre Optic Cables attract any noise", most results return that they attract virtually no noise. Is this the case or are there some exceptions?
5
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5answers
5k views

Implement send-only (one-way) Ethernet cable

I want to build a unidirectional comminucation. In transportation layer of this device, it needs a one-way media to send data from side A to side B. All commercial products use SFP. I tested some SFP ...
3
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2answers
1k views

Low cost UART over fibre

I need to extend an existing 5V UART over fibre for isolation reasons. Digital isolators / optos are no good as I need more isolation than that (0.1pF coupling max. from one side to the other). UART ...
2
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3answers
6k views

Convert dB/km to /km

please explain How is 0.22 dB/km equal to 0.0507 km^(-1) I tried doing 10 log x = its value in dB but it doesn't work here
2
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2answers
5k views

Can we send multiple signals in same core at the same time in the fiber optics? If yes, how? [duplicate]

I am curious to know how exactly does the fiber optics works. I understand the basic concepts of the fiber optics communications but am curious to know if there is a way to send multiple signals in ...
2
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1answer
358 views

Optical bandwidth and electrical bandwidth

I understand the concepts of electrical and optical bandwidths, but I encountered an example problem that used the following formula to calculate the electrical bandwidth: $$electrical bandwidth = 1/\...
2
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3answers
510 views

What does bandwidth mean in general, and in the context of the following examples?

Some examples : 1.The bandwidth of an operational amplifier 2.The bandwidth of a transmitted amplitude modulated signal 3.The bandwidth of a signal used in coaxial cables / optic fibre cables 4.The ...
2
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2answers
400 views

Long Distance Wired Data Connection

I am working on a project where I am going to need long distance communication and I am unsure the best way to go about it. I am mainly trying to decide between fiber optic or Ethernet and decide some ...
2
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1answer
1k views

Media converter (eth/fiber) problem in communication

I have a system which looks like that: CPU(macbook)<-->thunderbolt<-eth->ethernet media converter<-fiber->ethernet media converter<-eth->raspberry pi 2. Both CPU and RP2 have static IPs. ...
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1answer
203 views

Oscilloscope for SFP+ Host Board Compliance testing

What major criteria should I consider when buying an oscilloscope to test compliance for an SFP+ host board? Examples would be helpful as well. I am looking for a high-end product since this is for ...
2
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1answer
2k views

How would the SFP+ transceiver interface (Linear vs Limiting) affect my design?

On my board, I'd like to replace an RJ45 port with an SFP+ transceiver to increase data rate to 10Gbps. In choosing an SFP+ module, I have noticed that the only MSA compliant interfaces can be ...
1
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1answer
625 views

What wavelength will achieve higher speed in optical fiber?

I've got quite easy question (and my attempt to solve it). So there is an optical fiber with Dispersion index: D = -100ps/nm•km, length: L = 10km. The question is: which wavelength will achieve faster ...
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4answers
174 views

Fiber-optic transceiver ICs for applications other than fiber-optic Ethernet? [closed]

When we talk about fiber-optic transmission, we almost always talk about copper to fiber-optic Ethernet conversion using fiber-optic transceivers. But since fiber-optic communication is just ...
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1answer
189 views

How Gigabit Ethernet is achieved in fiber optics?

I understand how 1000BaseT works on Cat 5 cables: It uses clock rate at 125 MHz, 4D-PAM5 data encoding to transmit 2 bit per cycle and it uses the four pairs of the cable. The math is quite simple: ...
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2answers
588 views

Using SFP modules from a microcontroller

I'm interested in having an embedded device send data optically. This is for test and measurement, where having conductive cables is problematic since it will perturb the measurement. The device is ...
1
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2answers
1k views

what is the span of an optical fiber?

I am new to the fiber-optic communication systems, and in reading some relevant papers, I faced to the term "span length" (such as long-span link) which I cannot distinguish it from the length of the ...
1
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1answer
351 views

What is used to detect light from fiber optic signals in high speed Internet?

I'm curious, do they use photodiodes or something? As far as I know, that would be the cheapest way to do high speed communications over fiber (fibre? I'm 'murican) but I'm not sure.
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1answer
205 views

What are the different possibilities for delay distortion in fibre optic cabling?

Fibre optic cabling is often known for its extremely high speeds but is there anything that may develop delay issues in transmission via fibre optic cabling?
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2answers
315 views

Waveguides: How can you propagate at only one frequency?

In a rectangular waveguide, we know we can find cut off frequency as a function of mode and geometry. Is there a way to design the waveguide so to ensure that we can limit the frequency of ...
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1answer
64 views

Do electronic fiber optic selector switches exist?

From my research, I have been having a tough time finding and specifying a fiber optic selector switch or multiplexer. Do fiber optic selector switches exist? Background - Simple I have an ...
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2answers
80 views

What grade of fibre is used in optical fibre displays?

Optical Fibre displays such as Fibre Optic Trees probably isn't going to use cable designed for 10GBase-ER. So what grade of fibre is used in these displays? Clearly, it can't be terribly expensive. ...
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1answer
46 views

Material dispersion in fiber optics transmission

In plain English, why does material dispersion increase with wavelength in fiber optic transmission? I am aware that refraction index decreases with wavelength increase, i.e. pulse travels faster, but ...
1
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1answer
723 views

Differences and conversion between encoding techniques (NRZI, Manchester, MLT3)

I'm currently reading a lot about different encoding techniques for data transmission, in particular ethernet, fiber (and usb). 10Base Tx ethernet uses Manchester encoding for data transmission. But ...
1
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1answer
590 views

Optical coupler and splitter difference and explanation

Internally, what is the difference between an optical coupler and an optical splitter. If I have an input A on a 3db splitter, creating outputs B and C, can I send signals on B and C and have them ...
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0answers
167 views

How can we measure the coupling loss in a fused fiber Y coupler?

I'm trying to understand how the (power) loss in optical fibre works and I'm having some trouble. This is a classic 50/50 fused fibre Y coupler. The output on port 2 is the same as port 3 (so half ...
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0answers
73 views

Custom fiber optic cable simulation

I am looking to create a custom & precise static optical distribution along the length of a fiber optic cable. The idea involves manipulating an optical fiber during manufacturing to produce the ...
0
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1answer
490 views

Name of Fibre optic motherboard connector, like ethernet socket?

I am trying to find the name of fibre optics cable connector, so a fibre optic cable can be used on my design, does it have a official name? for about the past half hour - an hour I have been googling ...
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1answer
44 views

How come optical data modulation is faster than that of electrical modulation while optical modulation is done by electricity?

why optical data is of high bandwidth that that of electrical copper data bandwidth when we use electrical signal to achieve optical data modulation ?
0
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1answer
215 views

How to implement serial-to-fiber optic Ethernet with WIZnet W5500? [closed]

I'm using W5500 to implement a serial to Ethernet converter, but I need to transmit over fiber optic cables. I will have a TX cable and a RX cable. How can this be done since the output of W5500 is ...
0
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1answer
37 views

Optical receiver output voltage higher than power supply

The part is a optical receiver from Broadcom. It has TTL output, but specified with a maximum output-high voltage higher than the power supply. I wonder what's special structure internal may make it ...
0
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1answer
2k views

C-Band in Optical Fiber Communication [closed]

I've read that the C-Band used in optical communication ranges from 1530 – 1565 nm. Since one nanometer corresponds to 0.000000000299792458 GHZ, this is far less than 1 GHz. However, the C-Band is ...
0
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1answer
94 views

Does fibre optic cable bandwidth stack over the length of the cable?

If the maximum data bandwidth is sent down a fibre optic cable, constantly, maxing out the cable's capacity, how much data is in transit over any given distance? Perhaps I have an incorrect ...
0
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1answer
24 views

Multimode to singlemode optic fiber

I'm naive in this field, but I will need to use optic fibers for optogenetics application. I already know that my question will sound stupid for the most of you, please forgive me for that. My ...
0
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1answer
23 views

Shot noise variance of a channel for different bits

I've come across a question, where I had to calculate shot noise variance calculations of an optical link. As per the definition, shot noise in an optical channel is the current that arises from the ...
0
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1answer
29 views

Auto Configuring Circuit Routing

This may be a little hard to understand. I have little knowledge in electronics, but I had an idea about optical fiber for data transfer, as far as I understand, ports/inputs/terminals/pins must be ...
0
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1answer
108 views

Symbol rate and optical bandwidth relation

I am quite new to the field of optical communication, so perhaps this question is so easy. In reading some papers I have faced to the concept of optical bandwidth. For example, they say the symbol ...
0
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1answer
98 views

How to drive a HFBR-1541 optical transmitter?

I want to drive a HFBR-1541 optical transmitter (see page 7; 60mA output current), and I want the driver to have extended operating temperature range (at least starting from -20 degrees Celsius). The ...
0
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1answer
372 views

How to determine point of failure in photodiode circuit

I have a photodiode circuit which uses a fiberoptic pigtail photodiode as shown in the picture below: The photodiode is connected to an opamp as in the circuit below: The supply rails for the opamp ...
0
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2answers
67 views

What options do I have to combine and format 18 600Mbps ADC serial streams over QSFP+?

The 18 serial streams are not encoded or scrambled. The idea is to multiplex them onto one or more encoded serial streams at higher rates for onwards transmission over optical fiber.
0
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2answers
129 views

Complete fiber optic transmitter and receiver with standard fiber optic connector and integrated power circuitry? [closed]

I am having a very difficult time trying to find a simple, completely self-contained module to convert digital signals (<2Mbps) to fiber optic, that uses a robust, standard fiber optic connector (...
0
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1answer
150 views

Can I use sfp+ transceivers to interconnect PCIe x1 lane?

This is interesting because, sfp+ offers an inexpensive way to use optics to connect two PCIe x1 devices. But I do not know enough about sfp+ to know if I can simply connect up pcie lanes on a ...
0
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1answer
269 views

How to compute the maximum power I can get from an optical fiber?

I'm thinking of a project which requires powering a device with an optical fiber, but I don't know how to compute the maximum amount of power it can supply at the end. These are the parameters I know:...
0
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1answer
582 views

In Fiber Optic Telephone line, how light signals are converted to the voice signals? [closed]

I have been learning how internet data travels in different kind of Broadband access. In case of telephone broadband, voice signals travels through the telephone line. At the user premise, the modem ...
0
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1answer
90 views

Fiber transceiver operation

I recently bought a SFP fiber transceiver module to play around with. My idea was to connect the transmitter pins to a waveform generator, loop the optical output to the optical input with a fiber ...
0
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2answers
102 views

Drive electo-optic modulators with FPGA

I am currently using an FPGA (Virtex II NI RIO7831R) to generate the clock for a pulse generator used to drive a Linbo3 optical phase modulator. http://www.jdsu.com/en-us/Optical-Communications/...
0
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1answer
98 views

How can I make an optical circulator? [closed]

I need to a single mode 1550 optical circulator at my lab. I have a varied supply of components, but no circulator. Any idea how I can make one myself? Perhaps using coupler and isolator? Thanks. -D
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1answer
101 views

Fiber optics module: built in or plug-in module?

I am designing an Internet of Things system with fiber optics as its transmission medium (for its immunity to various kinds of interference and inability to carry a shock from a failed high voltage ...