Cognitive flow control based on channel quality conditions
A system and method which improve the performance of a wireless transmission system by intelligent use of the control of the flow of data between a radio network controller (RNC) and a Node B. The system monitors certain criteria and, if necessary, adaptively increases or decreases the data flow between the RNC and the Node B. This improves the performance of the transmission system by allowing retransmitted data, signaling procedures and other data to be successfully received at a faster rate, by minimizing the amount of data buffered in the Node B. Flow control is exerted to reduce buffering in the Node B upon degradation of channel qualities, and prior to a High Speed Downlink Shared Channel (HS-DSCH) handover.
1. A method for use in a Node B having a buffer, the method comprising:
monitoring an amount of data within the buffer;
monitoring an amount of additional data the buffer may accept;
calculating a capacity allocation;
transmitting the capacity allocation; and
receiving data in response to the capacity allocation, wherein the received data is equal to or less than the capacity allocation.
2. The method of claim 1 wherein the buffer comprises a plurality of buffers or sub-buffers.
3. The method of claim 1 further comprising;
receiving a channel quality index (CQI); and
calculating the capacity allocation based on the CQI.
4. The method of claim 3 wherein the CQI is transmitted by a wireless transmit/receive unit (WTRU) to the Node B in response to receiving data from the Node B.
5. The method of claim 1 further comprising;
receiving a capacity request from a radio network controller (RNC), the capacity request indicating an amount of data that the RNC has available to send to the Node B, wherein the Node B transmits the capacity allocation to the RNC in response to receiving the capacity request.
6. A Node B comprising:
a buffer;
a processor configured to monitor an amount of data within the buffer, monitor an amount of additional data the buffer may accept, and calculate a capacity allocation;
a transmitter configured to transmit the capacity allocation; and
a receiver configured to receive data in response to the capacity allocation, wherein the received data is equal to or less than the capacity allocation.
7. The Node B of claim 6 wherein the buffer comprises a plurality of buffers or sub-buffers.
8. The Node B of claim 6 wherein the receiver is further configured to receive a channel quality index (CQI), and the processor is further configured to calculate the capacity allocation based on the CQI.
9. The Node B of claim 8 wherein the CQI is transmitted by a wireless transmit/receive unit (WTRU) to the Node B in response to receiving data from the Node B.
10. The Node B of claim 6 wherein the receiver is further configured to receive a capacity request from a radio network controller (RNC), the capacity request indicating an amount of data that the RNC has available to send to the Node B, wherein the transmitter is further configured to transmit the capacity allocation to the RNC in response to receiving the capacity request.