A while ago I upgraded my TV antenna in preparation for Digital Switch-Over here in the UK. It's a high-gain "Triple Boom" design. The other day I started thinking what is the benefit of the 'triple-boom' design and how does it work? The booms are clearly angled, how does this effect things?
It also appears the elements are evenly spaced, in contrast to single-boom antennas, so I infer from this that the angling, and thus vertical distance between elements, leads to sensitivity at different frequencies. But why doesn't the horizontal spacing matter too (as in single boom designs) or does it? And why do higher-gain antennas with more elements just keep extending outwards but at the same angle? So a longer 'boom' means the furthest most elements are even further apart than normal. Doesn't this just mean they are resonant at even lower frequencies?
Comparing the performance of this antenna with traditional single-boom design shows it has a higher gain but also a wider acceptance angle. I can see how a triple boom array would increase gain, but why/how does it broaden the angle?