(ask) increase bandwidth of monopole antenna

dear all
can anyone explain to me how to increase bandwidth of monopole antenna (wire antenna)?
may be u can share a document about it
thanks you
best regards

Typically any monopole and dipole bandwidth is increased by making it thicker. Extreme bandwidths are achieved by triangular elements; dipoles are then named "butterfly". Many designs have been described from the 1920s till now.

thanks you jiripolivka

could you shared a document about monopole antenna? especially about formula to calculate bandwidth and effect of diameter monopole on bandwidth..

I think the actual realization depends a lot on the central frequency. For VHF-UHF the discone antenna is popular http://en.wikipedia.org/wiki/Discone_antenna . Especially at lower frequencies, the structure may be realized from radial wires to reduce weight.

I like discones. another trick is to load the top end with a capacitive disk