US 2003/0165155 A1 · Receiver for time division multiplex system without explicit time slot assignment

Abstract

A technique for a time division multiplex system in which access to shared broadcast communication media is granted on a demand basis. Particular connections are assigned slot times at the transmitter based on demand. However, no specific information regarding the assignment of time slots need be communicated to the receivers. The transmit side employs a forward error correction technique followed by multiplication by a cover sequence unique to each connection. All receivers listen to the broadcast transmission channel all of the time. The receiver assigned to each connection decodes the signals in such a manner that only the receiver with the correct cover sequence assigned to a particular connection will successfully decode the data associated with that connection. Data frames that fail the forward error correction process are discarded, and only those frames which are successfully decoded are passed up to a higher layer. The occurrence of an erroneously received frame is not necessarily always reported to the transmit side of the connection; only a packet level error indication is made. In this way, information containing time slot assignment need not be communicated between the transmitter and receiver, and yet data will be correctly received.

Claims44

Dependent claims

A method for communication in a time division multiplex system wherein access to a shared physical channel is assigned on a demand basis by allocating timeslots to provide multiple connections between transmitters and receivers, each given connection of the multiple connections having a given transmitter and receiver, the method comprising:

at a given transmitter,
allocating at least one time slot to carry forward link packet data on a forward link channel;
dividing a given packet into at least one frame;
encoding each of the at least one frames with a forward error correction code;
further cover sequence encoding each of the at least one frames with a cover sequence unique to the given connection between the transmitter and the given receiver;
combining cover sequence encoded frames from the given transmitter with at least one cover sequence encoded frame from another transmitter;
and
at the given receiver,
performing a cover sequence decoding process by combining a received signal with a cover sequence unique to the given receiver of the given connection, to provide a candidate frame;
and
decoding the candidate frame using a forward error correction decoding process, the cover sequence encoding operable to be decoded only by the cover sequence unique to the given receiver corresponding to the given connection.

8 more elements

A system for communication in a time division multiplex system wherein access to a shared physical channel is assigned on a demand basis by allocating timeslots to provide multiple connections between transmitters and receivers, each given connection of the multiple connections having a given receiver, comprising:

a transmitter,
the given receiver having a given connection to the transmitter;
a plurality of time slots operable to carry forward link packet data on a forward link channel, the packet adapted to be subdivided into frames;
an FEC encoder operable to encode the frames with a forward error correction code;
a cover sequence encode circuit at the transmitter operable to further encode the frames with a cover sequence unique to the given connection between the transmitter and the given receiver;
a combiner, for combining cover sequence encoded frames from the transmitter and at least one other transmitters;
a cover sequence decode circuit at the given receiver operable to decode a transmitted frame by combining a received signal with a cover sequence unique to the given receiver of the given connection to provide a candidate frame;
and
an FEC decoder at the given receiver operable to decode the FEC code using a forward error correction decoding process;
the cover sequence encoding operable to be decoded only by the cover sequence unique to the given receiver corresponding to the given connection.

7 more elements

Dependencies are inferred from the claim text.

Receiver for time division multiplex system without explicit time slot assignment

Life of this patent

Receiver for time division multiplex system without explicit time slot assignment

Life of this patent

Abstract

Claims44