Method and apparatus for estimating channel quality

A method performed by a user equipment comprising:

• receiving a first reference signal from a network node in a first downlink channel using a first downlink beamformer profile;
• receiving a second reference signal from the network node in a second downlink channel using a second downlink beamformer profile;
• performing at least a first measurement on the received first reference signal and a corresponding at least a second measurement on the received second reference signal;
• and
• transmitting a measurement report to the network node, for use by the network node in determining at least one transmission parameter for a future second uplink channel from the user equipment, in which a second uplink beamformer is to be used to receive on the second uplink channel, based on Ma a comparison or correlation between the first and the second measurements transmitted in the measurement report and an acquired estimate of the channel quality of a first uplink channel from the user equipment to the network node.

A user equipment comprising a processor and a memory, said memory containing instructions executable by said processor, whereby said user equipment is operative to:

• receive a first reference signal from a network node in a first downlink channel using a first downlink beamformer profile;
• receive a second reference signal from the network node in a second downlink channel using a second downlink beamformer profile;
• perform at least a first measurement on the received first reference signal and a corresponding at least a second measurement on the received second reference signal;
• and
• transmit a measurement report to the network node, for use by the network node in determining at least one transmission parameter for a future second uplink channel from the user equipment, in which a second uplink beamformer is to be used to receive on the second uplink channel, based on a comparison or correlation between the first and the second measurements transmitted in the measurement report and an acquired estimate of the channel quality of a first uplink channel from the user equipment to the network node.

A network node comprising a processor and a memory, said memory containing instructions executable by said processor, whereby said network node is operative to:

• receive a measurement report from a user equipment, wherein the measurement report is based on at least a first measurement made by the user equipment on a first downlink reference signal previously transmitted to the user equipment using a first downlink beamformer and at least a second measurement made by the user equipment on a second downlink reference signal previously transmitted to the user equipment using a second downlink beamformer;
• acquire an estimate of a channel quality of a first uplink channel from the user equipment, in which a first uplink beamformer has been used to transmit a first uplink signal on the first uplink channel;
• and
• determine at least one transmission parameter for a future second uplink channel from the user equipment, in which a second uplink beamformer is to be used to transmit on the second uplink channel, based on a comparison or correlation between the first and the second measurements received in the measurement report and the acquired estimate of the channel quality of the first uplink channel.

A non-transitory computer readable storage medium comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out a method performed by a base station, of estimating a channel quality of an uplink channel from a user equipment, the method comprising:

• receiving a measurement report from a user equipment, wherein the measurement report is based on at least a first measurement made by the user equipment on a first downlink reference signal previously transmitted to the user equipment using a first downlink beamformer and at least a second measurement made by the user equipment on a second downlink reference signal previously transmitted to the user equipment using a second downlink beamformer;
• acquiring an estimate of a channel quality of a first uplink channel from the user equipment, in which a first uplink receiver beamformer has been used to receive a first uplink signal on the first uplink channel;
• and
• determining at least one transmission parameter for a future second uplink channel from the user equipment, in which a second uplink receiver beamformer is to be used to receive on the second uplink channel, wherein the at least one transmission parameter is determined based on a comparison or correlation between the first and the second measurements received in the measurement report and the acquired estimate of the channel quality of the first uplink channel.