Method and apparatus for scheduling and modulation and coding selection for supporting quality of service in transmission on forward shared radio channels
View Patent ↗The invention is a process and system for controlling selection of which MS is to receive the next packet data transmission on a forward channel and selection of which plural MCS is to be used for the packet data transmissions on the forward channel. A process for controlling selection of MCS method to be used by a BTS ( 10 ) to transmit data packets over a forward shared channel to a MS ( 12 ) in accordance with the invention stores information at the BTS, the information containing MCS methods which may be selected to transmit data packets over the forward shared channel to the MS; receiving from the MS at the BTS a quality indication of transmission of data packets over the forward channel to the MS; and selecting a MCS method from a plurality of MCS methods which may be used to transmit data packets on the forward channel dependent upon the received quality indication.
1. A method comprising:
storing information at a base transceiver station, the information comprising a plurality of modulation and coding methods which are selectable to transmit second data packets over a forward shared channel to a mobile station following transmission of first data packets over the forward shared channel to the mobile station, wherein the plurality of modulation and coding methods comprise a plurality of groups of selectable modulation and coding methods, and wherein the information comprises correlating information that correlates selectable modulation and coding methods of a first group with frame error rate and correlates a second group of selectable modulation and coding methods with throughput determined by the mobile station;
receiving feedback from the mobile station at the base transceiver station based upon the transmission of the first data packets of a quality indication of transmission of the first data packets over the forward channel to the mobile station; and
selecting a modulation and coding method from the plurality of modulation and coding methods to be used to transmit the second data packets on the forward channel dependent upon the received quality indication of the feedback of the first data packets and based upon the stored correlating information; and wherein
the quality indication is processed at the base transceiver station to enable selection, from the plurality of groups of selectable modulation and coding methods, of a modulation and coding method to be used to transmit the second data packets from one of the groups with the modulation and coding method selected from each group optimizing a different characteristic of the transmission of the second data packets.
2. A method in accordance with claim 1 , wherein selection of one of the modulation and coding methods optimizes transmission of the data packets.
3. A method in accordance with claim 2 , wherein the quality indication of transmission comprises a ratio of Ec (pilot channel strength) to Nt (noise from other cells).
4. A method in accordance with claim 3 , wherein the quality indication of transmission comprises a function of frame error rate or a function of throughput calculated by the mobile station of the first data packets over a plurality of data transmissions over the forward channel from the base transceiver station to the mobile station.
5. A method in accordance with claim 2 , wherein the quality indication of transmission comprises a function of frame error rate or a function of throughput calculated by the mobile station of the first data packets over a plurality of data transmissions over the forward channel from the base transceiver station to the mobile station.
6. A method in accordance with claim 5 , wherein the function of frame error rate is an average and the function of throughput is an average.
7. A method in accordance with claim 1 , wherein the quality indication of transmission comprises a ratio of Ec (pilot channel strength) to Nt (noise from other cells).
8. A method in accordance with claim 7 , wherein the quality indication of transmission comprises a function of frame error rate or a function of throughput calculated by the mobile station of the first data packets over a plurality of data transmissions over the forward channel from the base transceiver station to the mobile station.
9. A method in accordance with claim 1 , wherein the quality indication of transmission comprises an average of frame error rate or throughput of the first data packets calculated by the mobile station over a plurality of data transmissions over the forward channel from the base transceiver station to the mobile station.
10. A method in accordance with claim 1 , wherein the receiving at the base transceiver station is over a reverse channel and the stored information is stored in two tables.
11. A method in accordance with claim 10 , wherein the channel is Reverse Quality Echo Channel (R-QIECH).
12. A method in accordance with claim 1 comprising:
processing the quality indication at the base transceiver station to provide multiple triggers which are a function of the quality indication and using the multiple triggers to select a single group of the plurality of groups of selectable modulation and coding methods from which the modulation and coding method used to transmit the second data packets is selected.
13. A method in accordance with claim 12 , wherein one of the characteristics of transmission is frame error rate and another of the characteristics is throughput.
14. An apparatus comprising a processor configured to:
store information comprising a plurality of modulation and coding methods which are selectable to transmit second data packets over a forward shared channel to a mobile station following transmission of first data packets over the forward shared channel to the mobile station, wherein the plurality of modulation and coding methods comprise a plurality of groups of selectable modulation and coding methods, and wherein the information comprises correlating information that correlates selectable modulation and coding methods of a first group with frame error rate and correlates a second group of selectable modulation and coding methods with throughput determined by the mobile station;
receive feedback from the mobile station based upon the transmission of the first data packets of a quality indication of transmission of the first data packets over the forward channel to the mobile station; and
select a modulation and coding method from the plurality of modulation and coding methods to be used to transmit the second data packets on the forward channel dependent upon the received quality indication of the feedback of the first data packets and based upon the stored correlating information; and wherein
the quality indication is processed by the apparatus to enable selection, from the plurality of groups of selectable modulation and coding methods, of a modulation and coding method to be used to transmit the second data packets from one of the groups with the modulation and coding method selected from each group optimizing a different characteristic of the transmission of the second data packets.