Still about WiGig backwards compatibility.
According to the press release by the Wi-Fi Alliance:
[i]The WiGig specification defines protocols to deliver data transfer rates measured in gigabits rather than megabits and supports a new range of applications and usages. The specification also defines procedures to enable WiGig-compliant devices to hand over sessions to operate in the 2.4 or 5 GHz band. It is expected that a new class of [b]tri-band Wi-Fi CERTIFIED devices[/b] will offer multi-gigabit wireless speeds while helping to ensure backward compatibility.[/i]
My assumption: The WiGig-compliant devices are capable of operating on 2.4, 5 or 60 GHz frequency bands. If a 'pure' WiGig environment - only WiGig APs and STAs are used, no legacy 802.11 radios - exists, the network will operate on 60 GHz band and the maximum data rate of 7 Gbps can be achieved.
If the network sees any 802.11a, b, g, or n devices, however, it will switch to the related frequency band(s). For example, if an 802.11g STA enters a WiGig AP-enabled network, the AP will decide to operate on 2.4 GHz instead of 60 GHz band.
Can I draw an analogy between WiGig backwards compatibility and 802.11n protection mechanism? Of course, the real issue is complicated. How about a mix environment with 802.11a/b/g/n and WiGig radios? What data rate(s) will be achieved in this case?
The issue with that would be that the signal propogation properties of WiGig would be considerably less than those of 2.4 or 5.0 Ghz therefore I anticipate that it would not be analogous to protection mechanisms but actually incorporate seperate radios to support all technologies.
However I would anticipate that WiGig applications would be considerably shorter range and as such does not currently fit the distributed architecture that we use for wireless deployments today.
Just my 2 cents
You mentioned the cell phone usage. Have you heard of the following statement: it is not a good idea to answer the phone call immediately following the ring, because the electromagnetic radiation during the first 7 seconds is considerably significant.
The WiGig end products will no doubt conform to the safety/heath standards, but it is still interesting to read more about the operation mechanism of 60 GHz devices.
Haven't actually heard of that one. If you hold the phone even a short distance away from your head it can cut down on the amount of energy passing through the skull [ especially the eyes ]. Headsets are good too.
If you have a spectrum analyzer that covers cell frequencies, you can get a surprise as to how much "juice" is produced by a cell phone.