Method and apparatus for contention window size adjustment

A method performed by a base station, comprising:

• receiving a first group of feedback signals from a user equipment (UE) indicating a first state corresponding to data transmitted in a first band used by a carrier, the first group of feedback signals comprising at least one first feedback signal;
• receiving a second group of feedback signals from the UE indicating a second state corresponding to data transmitted in the first band used by the carrier;
• determining a first scaling factor α for one of the at least one first feedback signal;
• determining a ratio of the first group of feedback signals to the first group of feedback signals and the second group of feedback signals;
• and
• comparing the ratio to a threshold to determine a contention window size of the first band for a contention window;
• generating a random back-off counter within the contention window, and adjusting the contention window size of a transmitter of the base station, based on the ratio;
• wherein the first scaling factor α substitutes a weight of the one of the at least one first feedback signal in determination of the ratio of the first group of feedback signals to the first group of feedback signals and the second group of feedback signals.