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I agree with laza that a suitable choice is the discone antenna. It's omnidirectional with "8" radiation pattern as lbda/2 dipole. Can cover frequencies fmin:fmax~1:4 so no problem for your band. I can send you detailed info about design.
First I need to know if the 100MHz bandwidth is for VSWR( 2:1 or 3:1 ) or Gain -3dB from center Frequency.
Next the kind of pattern, ominidirectional or directional.
If directional, front/back ratio, gain etc.
But I can estimate something: If the array you are looking for is directional, the best choose is a Log Periodic Dipole Array.
Try to use a double boom to do the phase shift and feed the elements. I had best results with that arrange.
Hope to help