An antenna enables compact and robust multiband operation of portable radios. According to some embodiments, the antenna includes: a first rolled conductive strip having a first section with overlap between successive turns of the first conductive strip and a second section with no overlap between successive turns of the first conductive strip, the first section having an insulating layer between the overlapping successive turns of the first conductive strip; a second rolled conductive strip; and a flexible sheet to which both the first conductive strip and the second conductive strip are bonded.