A multi-band antenna that operates in at least two non-harmonically related frequency bands, such antenna comprising: a linear low frequency antenna for a relatively low frequency band of the at least two non-harmonically related frequency bands, the low frequency antenna extending on a proximal end orthogonally from a ground plane along a predominant axis and electrically isolated from the ground plane; a relatively high frequency antenna for a relatively high frequency band of the at least two non-harmonically related frequency bands, the relatively high frequency antenna being disposed on and electrically connected to the proximal end of the low frequency antenna with an apex of the relatively high frequency antenna disposed adjacent the ground plane coincident with the proximal end of the low frequency antenna and a base of the relatively high frequency antenna extending away from the ground plane coaxial with the predominant axis and surrounding the low frequency antenna; the relatively high frequency antenna is cone-shaped, and characterised in that the antenna further comprises: a first tubular sleeve extending from the ground plane coaxial with the predominant axis, said tubular sleeve being electrically isolated in a direct current sense from the ground plane and the relatively high frequency antenna, wherein said first tubular sleeve is capacitively coupled to the relatively high frequency antenna and to the ground plane so that the size of the said first tubular sleeve determines frequency characteristics of said relatively high frequency antenna; and a second tubular sleeve lying coaxial with the predominant axis extending from a marginal edge of the base of the relatively high frequency antenna away from the ground plane, said second tubular sleeve being electrically isolated from the relatively high frequency antenna and the low frequency antenna. a linear low frequency antenna for a relatively low frequency band of the at least two non-harmonically related frequency bands, the low frequency antenna extending on a proximal end orthogonally from a ground plane along a predominant axis and electrically isolated from the ground plane; a relatively high frequency antenna for a relatively high frequency band of the at least two non-harmonically related frequency bands, the relatively high frequency antenna being disposed on and electrically connected to the proximal end of the low frequency antenna with an apex of the relatively high frequency antenna disposed adjacent the ground plane coincident with the proximal end of the low frequency antenna and a base of the relatively high frequency antenna extending away from the ground plane coaxial with the predominant axis and surrounding the low frequency antenna; the relatively high frequency antenna is cone-shaped, and characterised in that the antenna further comprises: a first tubular sleeve extending from the ground plane coaxial with the predominant axis, said tubular sleeve being electrically isolated in a direct current sense from the ground plane and the relatively high frequency antenna, wherein said first tubular sleeve is capacitively coupled to the relatively high frequency antenna and to the ground plane so that the size of the said first tubular sleeve determines frequency characteristics of said relatively high frequency antenna; and a second tubular sleeve lying coaxial with the predominant axis extending from a marginal edge of the base of the relatively high frequency antenna away from the ground plane, said second tubular sleeve being electrically isolated from the relatively high frequency antenna and the low frequency antenna. a first tubular sleeve extending from the ground plane coaxial with the predominant axis, said tubular sleeve being electrically isolated in a direct current sense from the ground plane and the relatively high frequency antenna, wherein said first tubular sleeve is capacitively coupled to the relatively high frequency antenna and to the ground plane so that the size of the said first tubular sleeve determines frequency characteristics of said relatively high frequency antenna; and a second tubular sleeve lying coaxial with the predominant axis extending from a marginal edge of the base of the relatively high frequency antenna away from the ground plane, said second tubular sleeve being electrically isolated from the relatively high frequency antenna and the low frequency antenna.