Apparatus for selected provision of linear and/or circular polarity signals

摘要

The invention relates to apparatus and method which can be used to receive broadcast digital data. The apparatus and method are provided at one or more receiving locations and is connected to one or more broadcast data receivers at each location. The apparatus is capable of receiving and processing data in linear and/or circular polarity formats and the operating condition of the same can be altered in response to a command signal broadcast to the receiving locations prior to the transmission of data in a new format such as to the change in the operating condition of the apparatus to receive and process linear as well as the previously broadcast circular polarity format data.

主权项

1. Apparatus for receiving broadcast digital data disposed at plurality of fixed locations, said apparatus at each of said fixed location comprising:
an antenna with which is mounted a low noise block (LNB); a waveguide probe for linear polarity format data signals; a waveguide probe for circular polarity format data signals; and a processing circuit to allow circular and linear polarity format data to be selectively received and processed, wherein said processing circuit includes a series of data outlets allowing selective passage of the processed data to at least one broadcast data receiver at that fixed location for the generation of video and/or audio, said outlets allowing the selective passage of the processed data in either one of or both of circular and linear polarity formats in response to a selection signal; wherein the processing circuit causes said apparatus to operate in a first state to receive and process data in only one of said linear and circular polarity formats and thereafter, upon receipt of a broadcaster command transmitted to the said apparatus effects a change of state of operation of the apparatus to operate in a second state enabling the apparatus at that fixed location to receive and process, at the same time, data in both linear and circular polarity formats, wherein said change of state of operation of the apparatus and the selective passage of the processed data in either one of or both of circular and linear polarity formats are achieved without the need for physical or mechanical alteration or movement of the apparatus at that fixed location, and wherein said selection signal indicating the selective passage of either one of or both of circular and linear polarity format data from the data outlets is transmitted by the broadcast data receiver connected to the outlets, wherein, when the data signals are received in both the circular and linear polarity formats during the second state of operation of the apparatus, the processing circuit processes the received data such that only said circular polarity format data signals are passed through a 3 dB hybrid to power dividers to split said circular polarity data signals into CP Hi and CP Lo data signals, which pass through respective oscillators to the series of data outlets, while said linear polarity format data signals pass through respective oscillators and one of the outlets.