Ben, Answers inline.
** ** > > Let me try that example again....missing a nested list segments.**** > > ** ** > > Features**** > > · Explicit indication of authoritative time ranges and frequency ranges > associated with the response**** > > What is “authoritative time range” and where does the value come from or > how is the value calculated?**** > > · Within a spectrum list, missing frequencies now can be interpreted > unambiguously as unavailable without magic values**** > > I agree, but I still think that any radio vendor writing code for a > specific ruleset would know that any channels not listed are simply not > available. > > I am not even sure why the discussion of showing "unavailable" came up, > but I can guess that it may be due to some language in one of the proposed > regulations (ETSI or OFCOM ?) that implies a "push" model for indicating > that a channel is no longer available. Maybe this started as an > discussion on how to satisfy that requirement? > No, actually. It arose from the language in the FCC TVWS rules, where it's expressed as permitted and un-permitted channels, rather than ETSI/OFCOM that expresses a power level for each channel. > > > > **** > > · If there are gaps in time intervals, it also may be interpreted > unambiguously as no available frequencies**** > > Is this statement true only for the *timeRange* specified?**** > > · Still allows the protocol to express of full mask where allowed**** > > How do we express a *full mask* in the protocol? > > I don't know what is meant by a "full mask". If the intention is to > describe emission limits so that a WS implementation can be adaptable to > different regions and changes in regional regulations over time, this > representation does not allow the full story. For an FCC compliant TVBD > there are limits on PSD (BTW it appears from this example that "Psd" means > maximum TX power and not the PSD limit n the FCC regulations) which vary > based on device category and usage, there are max power in the TV channel > limits that depend on device category and what is going on in adjacent TV > channels, and other limits that require you examine other sections of the > regulations such as 15.209 to understand (which specifies adjacent channel > field strength limits for example). I don't seen how those other values > are represented in this format - for example how would we encode " 200 > microvolts/meter electromagnetic field strength measured in 120 kHz > bandwidth at a distance of 3 meters s from the transmitter" which is a > requirement US TVBDs must meet for emissions outside the channel of use. > > So I am back to the question I was asking - what is the intended purpose > of specifying a "mask"? > One exciting aspect of managing spectrum via a Database is that you can move the complex logic you've described into the Database. The "200 microvolts/meter electromagnetic field strength measured in 120 kHz bandwidth at a distance of 3 meters s" can be converted to EIRP, and the Database may overlay all the applicable rules and present to the Device a mask that it must meet, taking into account its device type, device class, etc. Note that the DB's response is tailored to the device that makes the query. For devices that contain software-defined radios, they just have to fit within the envelope defined by the mask and not have to carry around these per-regulator rules. Should the protocol be ready to support such a model? or only be restricted to support the (few) existing rule sets? -vince
_______________________________________________ paws mailing list [email protected] https://www.ietf.org/mailman/listinfo/paws
