IS that a fact or a bit of wishful cheerleading? The reason I ask that, with it being only 500 MHz difference and the fact that at the present configuration of the systems deployed, you are correct to a degree. I've defracted <2GHz microwave signals and quite successfully, so successfully it almost got be kicked off a project.
Well, the fact is that both defraction and penetration get worse (assumeing you like those attributes) as the frequency increases.
I have been told that the performance of the current (L)MMDS frequencies would be unacceptable for mobile, non-directional communications. I will also admit that 2.4GHz is pretty close to 1900 MHz, so who knows.
As an aside, whenever you can employ directional antenna, the advantage of CDMA is reduced. CDMA provides interference resistance, which is important with lots of user sending out undirected signals that interfere with one another -- the mobile environment.
Directional signals, however, provide an alternative means for preventing interference between users. Thus, they reduce the benefits of CDMA. Current CDMA is best for "the last mile," not the loop. That's fine. There are lots and lots of last miles to be filled. |
