UWB frequency allocation in DS and OFDM

Dear all,

I have some confusion in the DS and OFDM UWB. I hope anyone could clarify my idea. As I know, UWB has two types. One is using Direct Sequency. Another one is OFDM.
(1) Are both of them allociated from ~3GHz to ~10GHz?

(2) I searched from the internet. There are two different kind of frequency band division. (i) http://staccatocommunications.com/pa...ON_14Aug03.pdf
(ii)
http://www.microwavers.org/files/uwb/murray-uwb2.pdf
Actually, which one of the the frequency band divison is correct? Or, one is for DS and another one is for OFDM? If yes, could you tell me which one correspond to which frequency band division?

(3) I know there is several mode for application. How many modes are available now? I just know that mode-1 is corresponding the first 3 sub-bands (~3GHz - ~5GHz). How is other mode?

(3) I know there are one association called - WiMedia association. This association is using OFDM scheme or DS scheme? Is there any other association? Then what this association support?

(4) Where could I get the information about the frequency band allocation? Since I need to refer this reference for my report typing.

Thanks for your reply.

wccheng