Originally Posted by 300ohm
Dont really know until more smart antennas come out. Most smart antenna designs to date involve phase shifting to change the direction of the antenna. That really doesnt work out too well with bowties or other higher gain antennas. So look for most smart antennas to be local area antennas, at least in the immediate future.
NONE of the DTV Smart Antenna patents I've read work via phase shifting,
although that is a very viable technique for Adaptive Antenna Arrays (AAA).
Most of the patent disclosures describe forming a beam towards 16 compass
headings by summing the output of (say) the North and East antennas
with equal Preamp gain weighting to receive from NE and 3/4 N + 1/4 E to
receive from NNE, etc.....it's not optimal, but it's fairly low cost...
In Europe they use multiple tuners with Maximal Ratio Combiner (MRC) software
in dual and quad diversity DVB-T receivers (currently available for cars & buses).
MRC is a far superior technique, working in concert with the adaptive equalizer
to coherently sum ALL of the multipath components on ALL of the antenna inputs,
irrespective of phase relationships...but it has yet to get out of the lab for ATSC.
More info re "Maximal Ratio Combiners":http://www.avsforum.com/avs-vb/showt...php?p=13015675http://www.avsforum.com/avs-vb/showthread.php?p=5842783
BTW: There are 100's (1000's?) of papers and PhD theses re EQUALIZATION and
dozens (100's?) re MRC and other combining techniques, but very few re joint
optimization of the collective processes...anyone looking for a PhD research topic????