A broadband microstrip antenna formed on a printed circuit board has a first planar side comprising a plurality of electrically conductive planar v-shaped antenna segments, each v-shaped antenna segment comprising an open end formed by non-parallel sides and a closed end formed by an intersection of the non-parallel sides. The open end of each v-shaped antenna segment is electrically connected to one or more adjacent v-shaped antenna segments forming a series of electrically connected v-shaped antenna segments. The closed end of a centered v-shaped antenna segment provides a feed point for the one or more adjacent v-shaped antenna segments.

A broadband microstrip antenna formed on a printed circuit board has a first planar side comprising a plurality of electrically conductive planar v-shaped antenna segments, each v-shaped antenna segment comprising an open end formed by non-parallel sides and a closed end formed by an intersection of the non-parallel sides. The open end of each v-shaped antenna segment is electrically connected to one or more adjacent v-shaped antenna segments forming a series of electrically connected v-shaped antenna segments. The closed end of a centered v-shaped antenna segment provides a feed point for the one or more adjacent v-shaped antenna segments.

The invention relates to an antenna designed to emit and/or receive surface waves with a decametric, hectometric or kilometric central wavelength .sub.0, characterised in that it comprises at least one horizontal wire aerial element of between 0.5.sub.0 and .sub.0 in length, and at least three vertical wire aerial elements of the same length between 0.03.sub.0 and 0.1.sub.0, arranged in a same plane and each comprising an upper end and a lower end, said upper ends being connected to the horizontal wire aerial element, said lower ends being designed to be connected to a conducting medium having a substantially horizontal surface. The invention also relates to an antenna, an antenna array and a use of an antenna or of an antenna array.

The invention relates to an antenna designed to emit and/or receive surface waves with a decametric, hectometric or kilometric central wavelength .sub.0, characterised in that it comprises at least one horizontal wire aerial element of between 0.5.sub.0 and .sub.0 in length, and at least three vertical wire aerial elements of the same length between 0.03.sub.0 and 0.1.sub.0, arranged in a same plane and each comprising an upper end and a lower end, said upper ends being connected to the horizontal wire aerial element, said lower ends being designed to be connected to a conducting medium having a substantially horizontal surface. The invention also relates to an antenna, an antenna array and a use of an antenna or of an antenna array.

An antenna apparatus may include: a feed line; a ground plane disposed around a portion of the feed line; a feed via electrically connected to the feed line; a first end-fire antenna pattern disposed in front of the ground plane to be spaced apart from the ground plane, and electrically connected to the feed via; a second end-fire antenna pattern electrically connected to the feed line and disposed farther forward than the first end-fire antenna pattern; and a third end-fire antenna pattern electrically connected to the feed via, and disposed in front of the first end-fire antenna pattern in such a manner that a portion of the third end-fire antenna pattern overlaps the second end-fire antenna pattern.

A communication system where a central node (base-station or access point) communicates with multiple clients in its neighbourhood using transparent immediate beam-forming. Resource allocation and channel access is such that the central node does not necessarily know when each client starts its transmission. Receive beam-forming in such a system is not possible, as beam-forming coefficients for each client should be selected according to the particular channel realization from that client to the central node. Each client is detected early in its transmission cycle, based on either a signature that is part of the physical characteristics unique to that client, or based on a signature that is intentionally inserted in the clients' signal, and accordingly adjusts its beam-forming coefficients.

A communication system where a central node (base-station or access point) communicates with multiple clients in its neighbourhood using transparent immediate beam-forming. Resource allocation and channel access is such that the central node does not necessarily know when each client starts its transmission. Receive beam-forming in such a system is not possible, as beam-forming coefficients for each client should be selected according to the particular channel realization from that client to the central node. Each client is detected early in its transmission cycle, based on either a signature that is part of the physical characteristics unique to that client, or based on a signature that is intentionally inserted in the clients' signal, and accordingly adjusts its beam-forming coefficients.

A complex and intricate GNSS antenna that is created using inexpensive manufacturing techniques is disclosed. The antenna combines a loop antenna and a cross dipole antenna together, in a single plane, to create an optimal GNSS gain pattern. The antenna structure is symmetric and right-hand circular polarized to force correct polarization over a wide range of frequency and beamwidth. The feed structure is part of the antenna radiating element.

A complex and intricate GNSS antenna that is created using inexpensive manufacturing techniques is disclosed. The antenna combines a loop antenna and a cross dipole antenna together, in a single plane, to create an optimal GNSS gain pattern. The antenna structure is symmetric and right-hand circular polarized to force correct polarization over a wide range of frequency and beamwidth. The feed structure is part of the antenna radiating element.

A dual band compatible antenna device includes a first branch electrode having a first electrode portion connected to a common electrode with a first adjustment element interposed between the first electrode portion and the common electrode and a second branch electrode having a second electrode portion connected to the common electrode with a second adjustment element interposed between the second electrode portion and the common electrode. The first electrode portion and the second electrode portion are provided on a line to have a length equal to or longer than of an electrical length of the first branch electrode and the second branch electrode.