It is very clever and takes the capabilities of radio to their theoretical limit, where every cycle can be a bit. It makes very efficient use of the radio spectrum, which is why there is so much interest. Normal radio works by modulating a carrier (the RF or radiofrequency) with a lower frequency (the IF or intermediate frequency) that is in turn modulated in a variety of possible ways by the data. This generates a shmear of radiation around the carrier frequency (called sideband) which is why spectrum is allocated in bands. At the receiver the received signal is demodulated with the carrier frequency to recover the IF with the data in it. The maximum datarate is related to the IF, not the carrier frequency.
All recent developments have been aimed at cramming as much data into as small a part of the spectrum as possible and recovering it reliably, using this mix of RF and IF. The current state-of-the-art is probably represented by the Wimax and US 3G technologies.
XG's technology requires as a minimum just two closely-spaced radio frequencies to transmit a bitstream, which can be at the same datarate as the radio frequency. It sends information by switching between the two frequencies at cycle boundaries (imagine a sine wave with some cycles stretched) and has no need of an IF stage. The economics are interesting - because it requires electronics that operates at the RF rate, I suspect (though I'm no radio engineer) that this is more expensive than the electronics of the IF stage. However, it is hundreds of times more efficient than current radio technologies. It also requires much less power.
Will it kill Wimax? No more than it will kill any other form of radio communication. It takes spectrum cost out because you can cram a lot more data into the same bandwidth. I don't think the companies that have paid billions for portions of the radio spectrum will be too pleased - they will have to write down their spectrum asset. However, that is sunk cost paid for by shareholders, who are used to telecoms losses by now.
It has to be converted to silicon, and the economics of silicon are volume-related. I see it being used in remote sensors and RFID rather than targeting relatively low volume applications like Wimax, although if the technology is as simple as they make out I can see it appearing everywhere eventually. It is certainly disruptive, but few Wimax service providers own any spectrum yet, so changing to a new technology just means dumping the old one. The low total cost of XG's system means that there's unlikely to be a market for second-hand equipment based on current radio technologies when it does hit - so long as it is capable of performing the same role.
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It is very clever and takes the capabilities of radio to their theoretical limit, where every cycle can be a bit. It makes very efficient use of the radio spectrum, which is why there is so much interest. Normal radio works by modulating a carrier (the RF or radiofrequency) with a lower frequency (the IF or intermediate frequency) that is in turn modulated in a variety of possible ways by the data. This generates a shmear of radiation around the carrier frequency (called sideband) which is why spectrum is allocated in bands. At the receiver the received signal is demodulated with the carrier frequency to recover the IF with the data in it. The maximum datarate is related to the IF, not the carrier frequency. All recent developments have been aimed at cramming as much data into as small a part of the spectrum as possible and recovering it reliably, using this mix of RF and IF. The current state-of-the-art is probably represented by the Wimax and US 3G technologies. XG's technology requires as a minimum just two closely-spaced radio frequencies to transmit a bitstream, which can be at the same datarate as the radio frequency. It sends information by switching between the two frequencies at cycle boundaries (imagine a sine wave with some cycles stretched) and has no need of an IF stage. The economics are interesting - because it requires electronics that operates at the RF rate, I suspect (though I'm no radio engineer) that this is more expensive than the electronics of the IF stage. However, it is hundreds of times more efficient than current radio technologies. It also requires much less power. Will it kill Wimax? No more than it will kill any other form of radio communication. It takes spectrum cost out because you can cram a lot more data into the same bandwidth. I don't think the companies that have paid billions for portions of the radio spectrum will be too pleased - they will have to write down their spectrum asset. However, that is sunk cost paid for by shareholders, who are used to telecoms losses by now. It has to be converted to silicon, and the economics of silicon are volume-related. I see it being used in remote sensors and RFID rather than targeting relatively low volume applications like Wimax, although if the technology is as simple as they make out I can see it appearing everywhere eventually. It is certainly disruptive, but few Wimax service providers own any spectrum yet, so changing to a new technology just means dumping the old one. The low total cost of XG's system means that there's unlikely to be a market for second-hand equipment based on current radio technologies when it does hit - so long as it is capable of performing the same role.