Abstract: Apparatus is provided to allow the reception and/or transmission of data signals at two different frequency bands. The apparatus includes a waveguide (4) which has a first section (6) of larger cross sectional area for receiving and/or transmitting the lower frequency band signals, and a reducing section (8) which leads to a section with a reduced cross sectional area in comparison to the first section (6) and this allows the receipt of the higher frequency band signals. In one embodiment sections of the waveguide can be rotated to allow the apparatus to be adjusted to any particular orientation to suit the particular circular polarity transmission type at the location at which the apparatus is provided at that time.

Abstract: Apparatus is provided which allows for the receipt and/or transmission of data signals, and, for the received signals, for the subsequent separation of the same into at least two sets of data signals which are orthogonal and provide these sets of data signals to subsequent processing components, whilst maintaining the isolation between the first and second data signal sets. For the transmission of the data signals the first and second sets of data signals are initially separate and then combined into one data set to allow the same to be transmitted.

Abstract: Apparatus is provided which allows for the receipt and/or transmission of data signals, and, for the received signals, for the subsequent separation of the same into at least two sets of data signals which are orthogonal and provide these sets of data signals to subsequent processing components, whilst maintaining the isolation between the first and second data signal sets. For the transmission of the data signals the first and second sets of data signals are initially separate and then combined into one data set to allow the same to be transmitted.

Abstract: Apparatus is provided to allow the reception and/or transmission of data signals at two different frequency bands. The apparatus includes a waveguide (4) which has a first section (6) of larger cross sectional area for receiving and/or transmitting the lower frequency band signals, and a reducing section (8) which leads to a section with a reduced cross sectional area in comparison to the first section (6) and this allows the receipt of the higher frequency band signals. In one embodiment sections of the waveguide can be rotated to allow the apparatus to be adjusted to any particular orientation to suit the particular circular polarity trans mission type at the location at which the apparatus is provided at that time.