Method and arrangement for determining a channel quality offset

摘要

A method and an arrangement in a first radio network node for determining a channel quality offset for a radio channel for sending data from the first radio network node to a user equipment are provided. The first radio network node receives from the user equipment channel quality information for the radio channel. The first radio network node estimates resource utilization and signal-to-noise-ratio for the user equipment. The first radio network node determines the channel quality offset based on the received channel quality information, the estimated resource utilization and the estimated signal-to-noise-ratio.

主权项

1. A method of operation in a radio network node configured for operation in a radio communication system, said method comprising:
receiving a reported channel quality from a user equipment that determines the reported channel quality based on measuring a signal-to-noise-and-interference ratio (SINR) for reference symbols transmitted by the radio network node on assigned time-frequency resources and adjusting the measured SINR according to a current value of a channel quality offset at the user equipment, as previously transmitted to the user equipment by the radio network node; determining a reference symbol SINR for the user equipment from the reported channel quality; estimating a resource utilization that reflects interfering use of the assigned time-frequency resources by one or more other radio network nodes; estimating a signal-to-noise ratio (SNR) without interference, for the user equipment; estimating a data symbol SINR for the user equipment as a weighted combination of the SNR and the reference symbol SINR, including weighting the reference symbol SINR in proportion to the resource utilization and weighting the SNR in inverse proportion to the resource utilization; and calculating a new value of the channel quality offset, based on a difference between the data symbol SINR and the reference symbol SINR; and transmitting the new value of the channel quality offset to the user equipment, for use in determining a subsequently reported channel quality.