Electronic – Recommened chips for datacommunication over a low-voltage AC power line

communicationpower line communication

A client wants to send data (think 100 … 10k baud) over a combined power / cable-TV coax cable, distances up to 1 km. The lower end of the spectrum (say up to a few MHz) is free, but the cable carries the 50 Hz 48 .. 60 Volt power. What would you recommend for this? I was thinking power-line modem chips, but those seem to be out of fashion (and hence difficult to get), and require quite a few external components. A DIY approach could be to couple a modulated carrier into the line and detect it with a PLL chip or even a PIC with DFT. But I hope chips exist for exactly this purpose?

Best Answer

Have you considered looking at the other end of the spectrum? Low-frequency communications, as you have rightly noticed, are not as common as they used to be.

There are many chips around that handle all the modulation, demodulation, etc at >1GHz - take the MRF24J40MC from Microchip (maybe not the cheapest solution) for example - 2.405Ghz to 2.475GHz. Or the ADF7241 from Analog Devices - again in the 2.4GHz range. There are many many more.

Yes, I know these are aimed at wireless communications, but then, what is Cable TV if not wireless communication with no aerial? The cable is basically a closed loop aerial between two points. A modulated high frequency signal being sent between two points through a medium - just using copper instead of air.