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> That said, I continue to remain dubious because his claims are fairly out there in terms of bandwidth. No additional bandwidth is required beyond what cell s

by lutusp 13y ago

> That said, I continue to remain dubious because his claims are fairly out there in terms of bandwidth. No additional bandwidth is required beyond what cell systems already provide. The idea behind this method is that each outgoing packet has some extra information about phase for each antenna that will be used to transmit it. The extra information is calculated using Perlman's data center and added to the data structure of a specific packet meant for a specific device. The extra information tells the transmitting antennas which phase delay to apply to maximize the signal at the device's current location. My point is that this method doesn't change the bandwidth required for the cell system -- in many ways everything is as it was before, except that each participating device experiences better reception. This system relies on a relatively simple phase adjustment at each transmitting antenna, but because of the number of devices, the number of antennas and the math involved, a dedicated data center would have to be added to an existing cell system. But there's no change in terms of bandwidth -- that remains the same.

ChuckMcM 13y ago
"The technology would do away with wireless network congestion by giving each smartphone and tablet its own super-fast connection instead of asking these devices to share bandwidth pumped out by a cell tower." "In demonstrations at his laboratory, Perlman showed off iPhones, Surface tablets, and TVs streaming massive files—the 4K UltraHD version of House of Cards from Netflix, for example—via his own wireless networking equipment" These are both bandwidth narratives, not signal quality narratives. (granted they are the naive reporter's narratives but still). His breakthrough is that "all these devices can stream 4K ultra HD" that says that somehow he getting more bits to more machines, and that is a function of bandwidth not signal strength. Lets assume for the moment that the basestation is connected to some multi-lambda super fiber with a 40G connection back to the Internet. He's going to give every LTE phone a 100Mbps to 1Gbps connection to that? That works for the first 400 or 40 people but then what? 5 bars and stuttering video? This story, and others like it, have made the argument that the problem is congestion not signal clarity. Congestion is a function of channel bandwidth and operation rate. That is what leaves me dubious, I haven't seen how he can increase the bandwidth of the channel with his gizmo.
- lutusp 13y ago
  I think the journalist didn't understand what he was seeing. Clearly if signal strength is improved and phase distortion is removed, the error rate will go down and this will improve apparent bandwidth, but without requiring more bandwidth than the system already can provide in principle. To me, the first sentence in your quote from the article is simply hyperbolic but has no connection with reality. The method doesn't do away with network congestion, it simply improves the signal at each participating device. > Congestion is a function of channel bandwidth and operation rate. I think the congestion this method addresses is that caused by unsophisticated signal treatment methods and an overall decline in performance. Obviously if the system can optimize the phase at each transmitting antenna and improve the received signal for each device, then more devices can use the system simultaneously. That's not how I would define "do away with network congestion", but again, I think the journalist just had no idea what he was describing.
  - TheEzEzz 13y ago
    I'm not sure if I'm reading you right (not my area of expertise), but my understanding of the system is that this does increase total bandwidth. Each cell phone gains access to the entire spectrum of the transmitting source, rather than all phones splitting/sharing the available spectrum. It's as if only a single cell phone was in a given tower cell, and the tower was dedicating all its bandwidth to that single phone.
    - lutusp 13y ago
      No, I don't think so. If that were true, the cell system would have to upgrade its throughput. That would make this scheme unattractive to cell companies. I think the reason for all the attention given to this method is because it greatly improves the performance of a cell system without requiring any bandwidth increase. Remember that dropped packets are at times a big limitation on cell system performance, and much existing bandwidth is often wasted on packets that don't get decoded properly because of weak signals. > It's as if only a single cell phone was in a given tower cell, and the tower was dedicating all its bandwidth to that single phone. If the system can adjust the phases of the transmitting antennas to maximize the signal strength to a particular device, for each transmitted packet, then for all practical purposes that's true -- the entire bandwidth of the system really does become available to that particular device, for the duration of each packet meant for it. I don't know the statistics on dropped packets, but I think it's substantial in modern times for high-speed networks. The ratio of dropped packets essentially represents a bandwidth decrease. If that could be eliminated, it would improve throughput, and someone will be tempted to claim that bandwidth has increased. Only sort of.

by lutusp 13y ago

ChuckMcM 13y ago

"The technology would do away with wireless network congestion by giving each smartphone and tablet its own super-fast connection instead of asking these devices to share bandwidth pumped out by a cell tower." "In demonstrations at his laboratory, Perlman showed off iPhones, Surface tablets, and TVs streaming massive files—the 4K UltraHD version of House of Cards from Netflix, for example—via his own wireless networking equipment" These are both bandwidth narratives, not signal quality narratives. (granted they are the naive reporter's narratives but still). His breakthrough is that "all these devices can stream 4K ultra HD" that says that somehow he getting more bits to more machines, and that is a function of bandwidth not signal strength. Lets assume for the moment that the basestation is connected to some multi-lambda super fiber with a 40G connection back to the Internet. He's going to give every LTE phone a 100Mbps to 1Gbps connection to that? That works for the first 400 or 40 people but then what? 5 bars and stuttering video? This story, and others like it, have made the argument that the problem is congestion not signal clarity. Congestion is a function of channel bandwidth and operation rate. That is what leaves me dubious, I haven't seen how he can increase the bandwidth of the channel with his gizmo.

lutusp 13y ago
I think the journalist didn't understand what he was seeing. Clearly if signal strength is improved and phase distortion is removed, the error rate will go down and this will improve apparent bandwidth, but without requiring more bandwidth than the system already can provide in principle. To me, the first sentence in your quote from the article is simply hyperbolic but has no connection with reality. The method doesn't do away with network congestion, it simply improves the signal at each participating device. > Congestion is a function of channel bandwidth and operation rate. I think the congestion this method addresses is that caused by unsophisticated signal treatment methods and an overall decline in performance. Obviously if the system can optimize the phase at each transmitting antenna and improve the received signal for each device, then more devices can use the system simultaneously. That's not how I would define "do away with network congestion", but again, I think the journalist just had no idea what he was describing.
- TheEzEzz 13y ago
  I'm not sure if I'm reading you right (not my area of expertise), but my understanding of the system is that this does increase total bandwidth. Each cell phone gains access to the entire spectrum of the transmitting source, rather than all phones splitting/sharing the available spectrum. It's as if only a single cell phone was in a given tower cell, and the tower was dedicating all its bandwidth to that single phone.
  - lutusp 13y ago
    No, I don't think so. If that were true, the cell system would have to upgrade its throughput. That would make this scheme unattractive to cell companies. I think the reason for all the attention given to this method is because it greatly improves the performance of a cell system without requiring any bandwidth increase. Remember that dropped packets are at times a big limitation on cell system performance, and much existing bandwidth is often wasted on packets that don't get decoded properly because of weak signals. > It's as if only a single cell phone was in a given tower cell, and the tower was dedicating all its bandwidth to that single phone. If the system can adjust the phases of the transmitting antennas to maximize the signal strength to a particular device, for each transmitted packet, then for all practical purposes that's true -- the entire bandwidth of the system really does become available to that particular device, for the duration of each packet meant for it. I don't know the statistics on dropped packets, but I think it's substantial in modern times for high-speed networks. The ratio of dropped packets essentially represents a bandwidth decrease. If that could be eliminated, it would improve throughput, and someone will be tempted to claim that bandwidth has increased. Only sort of.