3 ms·
The same is true for DSSS only within a relatively narrow frequency band, originally of at most a few tens of MHz, now up to a few hundred MHz. For UWB, the en
by adrian_b 3y ago
The same is true for DSSS only within a relatively narrow frequency band, originally of at most a few tens of MHz, now up to a few hundred MHz.
For UWB, the energy of the signal is spread over a much wider frequency band, of at least a few GHz and up to tens of GHz. Therefore UWB behaves like a white noise with a much greater bandwidth than DSSS.
It is not difficult to jam the entire band that can be used by certain kinds of DSSS signals or to receive all of it and process it digitally to search for signals within it.
Such operations are much more difficult for the much greater bandwidth used by an UWB signal.
- lxgr 3y agoAh, that makes sense, thank you! So if I understand it right, they'd be the same/very similar if we could do direct-sequence spreading over multiple GHz, but we can't, so we do UWB instead? Is the modulation just practically easier to achieve in hardware? And regarding jamming resistance: Couldn't a jammer just transmit random pulses in the frequency band in question? Why is jamming harder than just transmitting a lot of useless data on the same channel using whatever modulation the targeted transmitter uses as well? Or is there just too much space (or rather, time) to cover with reasonable transmit power?