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Comment Re:Rife with QRM, HAMs will NOT be happy! (Score 1) 143

by freaxeh (#34680086) Attached to: Using LED Ceiling Lights For Digital Communication
What I would like to see is a combination of this technology along with laser technology to distribute throughout an entire room invisible laser light, along with a fiber optic cabling that is tacked onto the side of power line cabling, its a sensible combination of power distribution and data distribution all rolled into one single power cable, so every light socket then automatically becomes a high bandwidth laser reception and transmission point, and every portable device then transmits back to the light socket via means of laser. But that would be amazingly costly at least in today's market, a decade or two down the road and this might just be possible, would definatley be pretty cool to have every light socket and every room an access point for unlimited bandwidth with future proofing built into it.

Comment Re:Rife with QRM, HAMs will NOT be happy! (Score 1) 143

by freaxeh (#34680014) Attached to: Using LED Ceiling Lights For Digital Communication

I was thinking more about modulating the DC feed to the LEDs but as you point out the data and power circuits are going to have to come together at some point and I suppose the solutions to that problem are isolation and grounding. Once standards are developed for both it should go okay. Its possible to do it safely, even if the switches have to be on a fibre backbone, or some such.

I suppose you could have a CAT5 switch in every section of a building which feeds data to every light socket via means of CAT5, but uses a fiber backbone for the long haul back to a central point, that would prevent lightning from passing any further past that room or section of a building. But I would imagine maintenance after a lightning strike or power surge would then require the complete disassembly of the entire roof to remove all of the dead and melted CAT5 and power cabling, not too different to what would normally happen if a normal light socket got struck by lightning to be honest, definitely more costly however.

Comment Re:Rife with QRM, HAMs will NOT be happy! (Score 1) 143

by freaxeh (#34679892) Attached to: Using LED Ceiling Lights For Digital Communication
You can't twist power cable, bad things happen, like current appearing on the neutral line from the live line, and things like reflected power heating up the cable, instead of transmitting power the cable will then just act as a heater, and a large amount of current making it back to the transformer, burning that out and tripping fuses, among other things. Hence why you get a warning sticker on every appliance with a really long extension cord on it, please don't lay the power cable in a circular fashion. And connecting CAT5 to anywhere near where a light socket is, will be a spectacularly bad idea, for example: one outside light socket gets struck by lightning and the lightning then makes the very short (1-2 centimetre) trip to your ethernet socket then suddenly your entire network sees millions of volts over every switch and computer in the building before its finally earthed out in the equipment racks containing all of your servers.

Comment Re:Rife with QRM, HAMs will NOT be happy! (Score 1) 143

by freaxeh (#34679648) Attached to: Using LED Ceiling Lights For Digital Communication

I think that's what the patents are for. They don't use BPL. The light fixtures are located in dropped ceilings. Above the ceiling each light fixture has another light sensor. The data comes from yet another lightbulb even higher above the dropped ceiling. Those really high up lightbulbs use WiFi.

http://appft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&u=%2Fnetahtml%2FPTO%2Fsearch-adv.html&r=1&p=1&f=G&l=50&d=PG01&S1=(%22building+illumination+apparatus%22.TTL.)&OS=ttl/%22building+illumination+apparatus%22&RS=TTL/%22building+illumination+apparatus%22 Go there and search for "BPL" and "BOPL"

[0088]The lights shown in FIG. 5, in accordance with an embodiment of the invention, will have AC wiring with data carriers such as S-BPL, and static locations encoded into the system. Thus a person 190 entering a hallway 192 with a communications badge 170 could use only those lights needed for his travel. As the person progresses toward a destination, the lights behind may be no longer needed and so may be programmed to turn off.

Power, which may be either AC or DC current is coupled through a power line bridge 150 with data from a network cable input, for example. The source of the data is not critical to the operation of the present invention, but may include various computer outputs such as might, for exemplary purposes, include control processor output or network connections such as commonly found on Local Area Networks (LAN), Wide Area Networks (WAN) or through the Internet. In accord with one embodiment, the wiring between power line bridge 150 and LED light source 161 is shielded by passing through a conduit or the like, defining a Shielded Broadband-over-Power-Line (S-BPL) connection that is both resistant to interfering communications and also produces almost no radiant energy.

And:

[0085]As seen in FIG. 4, the electrical wiring in the hallways and/or rooms may include BOPL.

At least they are considering using shielded power cabling, aka "S-BPL", but I would think using WiFi would be a wiser choice, one lousy installation of S-BPL can wipe out half a building with radio interference, and what happens to the radio signal once it reaches the end of the line? aka the light socket? are they going to be installing shielded light sockets too? I Hardly think so.

Comment Rife with QRM, HAMs will NOT be happy! (Score 1) 143

by freaxeh (#34679428) Attached to: Using LED Ceiling Lights For Digital Communication
From what I've read about this, while the LED lights are optical, the transmission line, aka the power line will still be used to carry data transmissions to and from the LED lights, I don't see how this or any other BPL tech being allowed by the FCC then again anything these days is allowed to pass through and transmit whatever it wants all over the Shortwave radio bands under FCC Part 15 rules, Plasma TV's being just one example which plasters the lower shortwave radio band with an insane amount of interference. Please lets stop using power lines for data transmissions, all it does is cause headaches and takes a dump all over the shortwave band! We've already got WiFi, we don't need yet another standard that is just going to end up plastering interference all over the entire street, and probably causing rife with our bodies as well. Just imagine what the implications would be of this, every person in your street or unit could then have a hardwired connection to your ethernet network as long as they knew the correct password, usually default, no need to use high powered wireless adapters anymore.... I can see how a means of optical data transfer would be a good idea over infrared, It would be more healthier for our brains than wireless, IRDA springs to mind, but as soon as you put the blanket over your laptop the signal drops out completely. Its a worthless technology which will just end up spluttering interference over the entire lower shortwave band, making the valuable and irreplacable shortwave band useless for long distance DX contacts, what happens when we need that band in times of emergency? Oh wait, we can't use it because somebody needs their broadband fix, doh!

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