OARIS — Response to a frequency range request to be supported by the PIM

In the Manage Frequency Usage use case, if the CMS requests a range of frequencies rather than a discrete set (see class frequency_set_request) then the response from the sensor subsystem does not properly model the subsystem adopting the requested state. Class selected_frequency_list contains a list of discrete frequencies. In particular a list with two frequencies in it is indistiguishable from the expected response to a request to use just those two discrete frequencies - as opposed to the range inbetween them.

Frequency band to designate a discrete or range of frequencies

The specification already contains an abstraction of the actual frequencies to use through the frequency band typedef. This class allows a discrete value to be mapped to particular frequencies supported by the sensor. The interface would be simplified without loss of flexibility or rigour by developing the semantics of the frequency_band_type such that it may refer to a discrete frequency or a frequency range.
The frequency_range_set class is then redundant (as a band may refer to a range) - a range of bands does not in general make sense as it would pre-suppose some logical organisation of the discrete frequency band type that it need not have. Consequently, the frequency_set_request union class is also redundant as there would only be the single way of representing frequency state on the interface as opposed to the current two styles; removing the union is a useful simplification.
The set_frequencies() method should both take a selected_frequency_list parameter mirroring the transmission_frequency_state() method.
Metadata pertaining to a frequency band (e.g. whether refers to a discrete frequency or a range) can be communicated using the Manage Subsystem Parameterts use case.