Apparatus for, and method of, receiving satellite television signals in an apartment building and providing television images in the receivers in such building

摘要

Digital packets, defined by a sync byte and then 130 MPEG2 compressed QPSK signal bytes, from a satellite transponder are reformatted prior to transmission to television receivers in apartments in a building wired to distribute video signals. A side byte between such sync and signal bytes in each packet indicates (a) any QPSK packet uncorrectable error and (b) processing information which allows automatic reconfiguration at the settop box. Additional FEC bytes correct to 8 errors within a MPEG2_QPSK packet. The system removes the FEC bytes and reframes the MPEG2_QPSK packets into a superpacket by converting a first number of the MPEG2_QPSK packets to a second number of MPEG2_QAM packets. An added sync byte indicates the beginning of each such MPEG2_QAM packet. The system adds side data bytes including any uncorrectable errors in each MPEG2_QPSK packet and adds a new, less complicated FEC to each MPEG2_QAM packet. The system modulates and upconverts the bytes in each MPEG2_QAM packet and passes them through a cable plant constructed to receive modulated QAM bytes (or NTSC signals) which are demodulated at the settop box. The additional FEC bytes correct to 8 errors within a MPEG2_QAM packet and are then removed. The superpacket is deframed to obtain the MPEG2_QPSK packets. After finding a television channel, the side bytes are processed to determine the frequency location of the other channels in the apartment receivers and the existence of uncorrectable errors. The MPEG2_QAM bytes are decompressed and encoded to reproduce the television images in the apartment receivers.