to create and rate content, and to follow, bookmark, and share content with other members.
Challenges with 80 MHz bandwidth signals
Question asked by
on Jul 6, 2011
on Jul 6, 2011 by tabbott
Show 0 Likes
What new challenges do 80 MHz bandwidth signals present that I haven't seen before?
No one else has this question
Mark as assumed answered
This content has been marked as final.
Show 1 comment
(Required, will not be published)
Jul 6, 2011 3:56 PM
Hi Gladys -
Glad you asked. There are challenges in making a transmitter, or receiver, that is double the bandwidth than it was in 802.11n. The analog path must be wider, and the baseband clock rate is twice as large.
But there are a few issues which may not be quite as obvious:
a. The spectral mask requirement in 802.11ac has a transition region that is 2 MHz wide. On an 80 MHz signal, the transition region is proportionally narrower than on a 40 MHz signal. Transmitter designers will need to keep this in mind when designing any windowing or filtering to meet the spectral mask requirement.
To help mitigate the above issue, the spectral flatness requirement in 802.11ac is looser, allowing more variation in subcarrier amplitude.
b. Related to the above, there are only 6 lower guard subcarriers and 5 upper guard subcarriers on both 40 MHz and 80 MHz signals. A receiver may use filtering to attenuate signals in adjacent carriers, and that filtering will require a proportionately narrower transition region on an 80 MHz signal.
Show 0 Likes
Retrieving data ...
N9030A screen grab using SCPI and Python
How to transfer a file from E5052B via GPIB to rasp pi
Question about N8973A NFA
How should we proceed so that the current is effectively fixed?