Measuring Wireless Performance (?)

[Ronald F. Guilmette]

As I just mentioned in my immediately preceeding post, I'm a total
neophite when it come to wirless networking, so I need to ask a
rather basic question.

In preparation for installing my first ever wireless network, I read
up on the subject awhile first, and I found several people who had
commented (in various places) that they had bought "upgrade" antennas
for their wirless cards, and that this helped them, either to make
connections where they otherwise couldn't, or else with throughput/
performance of their wireless link.

Being totally new to this stuff, I have no idea if I would benefit
from a better antenna for my wireless card or not, so I gotta ask:
How can I tell?

Are there some tools available for FreeBSD that would tell me about
stuff like:

    Received Signal Strength Indicator (RSSI)
    Failed Frame Transmission Count, etc.

and/or performance of the wirless link generally?

Humm... OK.  I just found this, but it seems to be a Windoze-only thing:

   http://sysnet.ucsd.edu/pawn/wrapi/

:-)