Abstract: An antenna array assembly comprises at least a first and second antenna element, each comprising at least one radiator element in a substantially parallel relationship to a respective ground plate, and an isolator bar disposed between the respective ground plates of the first and second antenna elements, the isolator bar being elongate having a cross-section comprising a T shape, the cross-section being across a long axis. The isolator bar comprises a support bar in contact with the ground plates forming the stem of the T shape, and a cross piece forming the top of the T shape. The cross piece of the isolator bar has a width in the cross-section of at least a quarter of a wavelength at an operating frequency of the antenna array, whereby to provide radio frequency isolation between the first and second antenna elements.

Abstract: An antenna array assembly comprises at least a first and second antenna element, each comprising at least one radiator element in a substantially parallel relationship to a respective ground plate, and an isolator bar disposed between the respective ground plates of the first and second antenna elements, the isolator bar being elongate having a cross-section comprising a T shape, the cross-section being across a long axis. The isolator bar comprises a support bar in contact with the ground plates forming the stem of the T shape, and a cross piece forming the top of the T shape. The cross piece of the isolator bar has a width in the cross-section of at least a quarter of a wavelength at an operating frequency of the antenna array, whereby to provide radio frequency isolation between the first and second antenna elements.

Abstract: A radio frequency transmission arrangement comprises a ground plate (8) having first and second opposite sides and a boss protruding from said second side of the ground plate (8), a first transmission line comprising a first elongate conductor (1) passing from the first side of the ground plate through an aperture (3) in the ground plate and the boss, and a second transmission line comprising a second elongate conductor (2) and a ground plane (6), the first elongate conductor (1) passing through the ground plane (6) to connect to the second elongate conductor. The boss has an end surface (4) disposed in a substantially parallel relationship with the ground plane (6) of the second transmission line, and there is a gap between the end surface of the boss and the ground plane.

Abstract: A radio frequency transmission arrangement comprises a ground plate having an aperture comprising a slot with an elongate cross-section and substantially parallel sides, and a first and second transmission line. The thickness of the ground plate is greater than a width of the slot. The first transmission line comprises a first elongate conductor on a first side of the ground plate and has an end terminated with a first termination stub. The second transmission line comprises a second elongate conductor on the opposite side of the ground plate and has an end terminated with a second termination stub. The first transmission line is arranged to cross the slot at a point adjacent to the first termination stub, and the second transmission line is arranged to cross the slot at a point adjacent to the second termination stub.

Abstract: A radio frequency transmission arrangement comprises a ground plate (8) having first and second opposite sides and a boss protruding from said second side of the ground plate (8), a first transmission line comprising a first elongate conductor (1) passing from the first side of the ground plate through an aperture (3) in the ground plate and the boss, and a second transmission line comprising a second elongate conductor (2) and a ground plane (6), the first elongate conductor (1) passing through the ground plane (6) to connect to the second elongate conductor. The boss has an end surface (4) disposed in a substantially parallel relationship with the ground plane (6) of the second transmission line, and there is a gap between the end surface of the boss and the ground plane.

Abstract: Potential radar pulses are detected in a received signal waveform at a terminal of a broadband radio communication system, and a reception time is ascertained for each of the potential radar pulses. A pair of pulses is selected having respective reception times separated by an allowed pulse repetition intervals. One or more further pulses is selected that is related to the selected pair by having a respective reception time separated from the respective reception time of at least one pulse of the pair of pulses by one or more pulse repetition intervals from the set of pulse repetition intervals.

Abstract: Potential radar pulses are detected in a received signal waveform at a terminal of a broadband radio communication system, and a reception time is ascertained for each of the potential radar pulses. A pair of pulses is selected having respective reception times separated by an allowed pulse repetition intervals. One or more further pulses is selected that is related to the selected pair by having a respective reception time separated from the respective reception time of at least one pulse of the pair of pulses by one or more pulse repetition intervals from the set of pulse repetition intervals.