On 25 Aug 2013, at 23:39, Vincent Chen <[email protected]> wrote: > All, > > As was brought up before (and at) the F2F, the current encoding for a > spectrum profile > has a "channelized" view: > - List of (startHz, stopHz, power) > - Has no ability to specify power level in "unavailable" ranges > > Example: > { > "point": { "startHz": 5.18e8, "stopHz": 5.24e8, "maxPsdDbmPerBw": 30.0 }, > "point": { "startHz": 5.24e8, "stopHz": 5.30e8, "maxPsdDbmPerBw": 36.0 }, > } > > Question: Should we use a more flexible encoding? > > There were two proposals made on the list: > - Option 1: List of (startHz, startPower, stopHz, stopPower) > - Option 2: Ordered list of (freqHz, power) > > At the F2F, we agreed that Option 2 was the more general form. > > Example: > { > "point": { "freqHz": 4.70e8, "maxPsdDbmPerBw": -56.8 }, > "point": { "freqHz": 5.18e8, "maxPsdDbmPerBw": -56.8 }, > "point": { "freqHz": 5.18e8, "maxPsdDbmPerBw": 30.0 }, > "point": { "freqHz": 5.24e8, "maxPsdDbmPerBw": 30.0 }, > "point": { "freqHz": 5.24e8, "maxPsdDbmPerBw": 36.0 }, > "point": { "freqHz": 5.30e8, "maxPsdDbmPerBw": 36.0 }, > "point": { "freqHz": 5.30e8, "maxPsdDbmPerBw": -56.8 }, > "point": { "freqHz": 6.98e8, "maxPsdDbmPerBw": -56.8 } > } > > This example explicitly specifies the power levels in the unavailable > frequency ranges. > > This example also shows that it's possible to encode "square edges" by having > two > points using the same frequency, but does allow for "slanted edges" for more > gentle roll-offs.
I recall discussion of whether interpolated ramps were a good idea, and clarification that having the same "stop" and "start" power would be effectively the same as having a "startHz" and "stopHz" with a single power level, and thus could also generalise to represent the channelised model. However I recall no discussion of the latter encoding - I thought the proposal was to go with your #1 above. BTW, what value of "Bw" would be used to calculate the Psd when the interval between points is not constant? Given the OFCOM and ETSI requirement for both a channel-wide in-block EIRP *and* a 100 kHz spectral density, how would these be encoded in either of these variations? Also, I don't understand the note about specifying power levels in "unavailable" ranges. You appear to be suggesting that the "magic value" of -56.8 dBm above indicates "unavailable", but I can't find the thread that gives the rationale for this. It only appears to be necessary because there's no scope within a single array of "points" to omit a range of frequencies, whereas option #1 allows that by explicitly only listing "available" ranges. kind regards, Ray _______________________________________________ paws mailing list [email protected] https://www.ietf.org/mailman/listinfo/paws
