Patent ID: 7061937
Filing Date: 2006-06-13
Classification: H04N

Abstract:
1. A communication system comprising: a first transmitting/receiving apparatus configured to transmit multiplexed program data to be transmitted from the first transmitting/receiving apparatus to a second transmitting/receiving apparatus, first transfer schedule table information indicating a schedule of the program data, and second transfer schedule table information concerning data to be transmitted from the second transmitting/receiving apparatus to the first transmitting/receiving apparatus, to filter means; the second transmitting/receiving apparatus configured to transmit data to the first transmitting/receiving apparatus, based on the second transfer schedule table information transmitted from the second transmitting/receiving apparatus; and a filter unit configured to receive the first transfer schedule table information and the second transfer schedule table information transmitted from the first transmitting/receiving apparatus, for filtering data transmitted from the first transmitting/receiving apparatus, based on the first transfer schedule table information, and for filtering data transmitted from the second transmitting/receiving apparatus to the first transmitting/receiving apparatus, based on the second transfer schedule table information, wherein the first transmitting/receiving apparatus transmits downstream data transmitted from the first transmitting/receiving apparatus to the second transmitting/receiving apparatus, schedule data which specifies contents of the downstream data by means of frequency and time, and schedule data for upstream data transmitted from the second transmitting/receiving apparatus to the first transmitting/receiving apparatus, the filter unit transmits the schedule data for the downstream data and that for the upstream data requested by the second transmitting/receiving apparatus, to the second transmitting/receiving apparatus, and transmits the upstream data to the first transmitting/receiving apparatus. the second transmitting/receiving apparatus transmits the upstream data and information for filtering the downstream data by the filter unit, to the filter unit, and the filter unit comprises: a CPU for controlling entirely the filter unit; a first reception interface for receiving transmitted data and schedule data from the first transmitting/receiving apparatus; a first filter circuit connected with the CPU and the first reception interface, to filter downstream data, based on control by the CPU; a first transmission interface for transmitting data outputted from the first filter circuit; a second reception interface for receiving data transmitted from the second transmitting/receiving apparatus; an A/D converter for analog-to-digital-converting transmission schedule data received through the first reception interface and the first filter circuit; a third reception interface for receiving the upstream data; a second filter circuit for filtering upstream data received through the third reception interface; and a second transmission interface for transmitting upstream data filtered by the second filter circuit, to the first transmitting/receiving apparatus, wherein the second filter circuit is controlled so as to receive data in a procedure which is the same as that taken for receiving the schedule data for downstream data, and the second reception interface receives the upstream data through a route different from a route through which the first reception interface receives the transmitted data and the schedule data from the first transmitting/receiving apparatus.