Feedback mechanisms for multicast/broadcast service in wireless communication networks

A method for providing a multicast/broadcast service (MBS) in a wireless OFDM/OFDMA system, comprising:

• causing a base station, that sends an MBS transmission to a plurality of subscriber stations over a single traffic channel shared by the subscriber stations, to receive uplink signals from the subscriber stations and to detect a negative acknowledgement (NACK) indication from each subscriber station that fails to receive the MBS transmission from the base station, wherein the uplink signals are transmitted by subscriber stations using time and frequency components based on applying a hash algorithm to medium control access (MAC) addresses of the subscriber stations;
• causing the base station to process the received NACK indication from the each subscriber station to generate a service outage percentage used in determining a burst profile for a subsequent MBS transmission to all of the subscriber stations over the single traffic channel;
• and
• operating the base station to use the single traffic channel to use the determined burst profile based on the received NACK indication from all of the subscriber stations in the subsequent MBS transmission to all of the subscriber stations;
• wherein
• the burst profile for the subsequent MBS transmission is more robust than that of a previous MBS transmission when the service outage percent is greater than or equal to a high outage percentage value;
• the burst profile for the subsequent MBS transmission is less robust than that of the previous MBS transmission when a number of consecutive MBS transmissions are successfully received or when the service outage percent is less than or equal to a low percentage value;
• otherwise the burst profile for the subsequent MBS transmission is same as that of the previous MBS transmission.

A system for providing a multicast/broadcast service (MBS) in a wireless OFDM/OFDMA network, comprising:

• a base station operable to transmit a scheduled MBS transmission to a plurality of subscriber stations over a single traffic channel based on a first data rate;
• a subscriber station, operable to generate a negative acknowledgement (NACK) indication when the subscriber station fails to receive the scheduled MBS transmission from the base station;
• an uplink communication channel for the subscriber station to transmit the NACK indication to the base station which processes the NACK indication in determining a second data rate to be used in a subsequent MBS transmission to the plurality of subscriber stations over the single traffic channel based on the second data rate;
• the subscriber station further configured to apply a hash algorithm to a medium access control (MAC) address of the subscriber station to evenly assign different time and frequency components in the uplink communication channel to the subscriber station, and to transmit one of a plurality of orthogonal codewords when indicating the NACK to the base station;
• and
• the base station further operable to select the second data rate based on received information on the NACK indication from the plurality of subscribe stations that share the single traffic channel, including a service outage percentage among the plurality of subscribe stations during prior MBS transmission based on the first data rate, and to use the single traffic channel to send the subsequent MBS transmission to the plurality of subscriber stations at the second data rate, wherein
• the second data rate is less than the first data rate when the service outage percent is greater than or equal to a high outage percentage value;
• the second data rate is greater than the first data rate when a number of consecutive MBS transmissions are successfully received or when the service outage percent is less than or equal to a low percentage value;
• otherwise the second data rate is equal to the first data rate.

A system for providing a multicast/broadcast service (MBS) in a wireless OFDM/OFDMA network, comprising:

• a base station, which sends an MBS transmission to a plurality of subscriber stations over a single traffic channel shared by the subscriber stations, to receive uplink signals from the subscriber stations and to detect a negative acknowledgement (NACK) indication from each subscriber station that fails to receive the MBS transmission from the base station, wherein the uplink signals are transmitted by subscriber stations using time and frequency components based on applying a hash algorithm to medium control access (MAC) addresses of the subscriber stations;
• the base station further to process the received NACK indication from the each subscriber station to generate a service outage percentage used in determining a burst profile for a subsequent MBS transmission to all of the subscriber stations over the single traffic channel;
• and
• the base station further to use the single traffic channel to use the determined burst profile based on the received NACK indication from all of the subscriber stations in the subsequent MBS transmission to all of the subscriber stations;
• wherein
• the burst profile for the subsequent MBS transmission is more robust than that of a previous MBS transmission when the service outage percent is greater than or equal to a high outage percentage value;
• the burst profile for the subsequent MBS transmission is less robust than that of the previous MBS transmission when a number of consecutive MBS transmissions are successfully received or when the service outage percent is less than or equal to a low percentage value;
• otherwise the burst profile for the subsequent MBS transmission is same as that of the previous MBS transmission.