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Power-Line Modem Range

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ASIC

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power line modem

What kind of range can I get from a power-line modem chip? I need about 3km. Is that possible if I keep the data-rate very low. i.e. around 100 bps?

I am thinking of either the ST chip or the Philips TDA5051A, but I don't mind doing my own solution, as long as I get the range at a reasonable cost.


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batdin

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power line modems

Do you think this signal can pass through power transformers? I don't suppose so.
 

ASIC

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power line modem transformer

No it cannot pass through the transformer, but that is really not my question here.

What distance can I expect on a straight line of AC power line based on the above (or similar) chips? Anyone has experience with this?

ASIC
 

mehdi

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powerline modem chip

hi dear
you can increase the range of modem by designing and using a power amplifier before coupling the signal into ac line.in addition this chips(ST7536 or TDA5051)
use simple modulation FSK or ASK.for gettig better performance you should use advanced modulation especially OFDM for your modem.
 

House_Cat

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modem range

ASIC - Your real problem is signal to noise ratio. The AC power line is exceptionally noisy, and the noise is not easily predicted.

Atmospheric noise (lightning, static discharge from wind, etc.), switching noise (appliances turning on and off, commutating noise from rotating machinery, etc), external RF (welding machines, induced radio and TV signals, home electronics, etc.), signal bypass (home and industrial broadband noise filters, transformers, line capacitance, etc.) - all are unpredictable in amplitude, frequency, and signal characteristic. Each of the noise sources will diminish your range for a detectable signal.

No, it is improbable you can get 3km out of you modem using a single driving point - regardless of power. As a matter of fact, you'll be lucky to get 50m.

Commercial applications depending on power line data transmission use high power booster repeaters at regular intervals along the signal path. Unless you are prepared to do that, you are better off transmitting the data over a public radio frequency through the atmosphere. You can encrypt the signal if necessary, and you can use modulation schemes that are noise tolerant. It would take less power to use atmospheric transmission over 3km than to try and overcome the noise on a 3km power line.
 

ASIC

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power line

Yes I came to the same conclusion, House_Cat. RF would solve all the problems once and for all.

The problem is my customer is a power-generating company, and they heard stories from China about power line mdems being deployed. My own research is that China has given up deploying power-line modems after more than 2 years of research.

Repeaters are not possible in my application either, as people like to steal them.

Is there any frequency-band available without a license, that can be used for this kind of transmission, and where the equipment is reasonably priced?


ASIC
 

House_Cat

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power line fsk modem

The frequency band for unlicensed operation depends on what country you live in. Some of the more restrictive countries will require a permit to operate a transmitting device. Other countries allow transmission on certain frequencies without a license, as long as the power is kept below a specified level.

You need to check the regulations for the reqion in which the project is located.

Another thing to look at would be what bands are heavily used in the area of operation. It wouldn't do to use microwave, for example, in a region with high power broadband microwave relay towers in the line of sight, or the 27Mhz band in the US where that 'citizen's band' is cluttered with truckers and kids chattering, etc.
 

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