Method and arrangement for CSI measurement

A User Equipment (UE), comprising:

• a memory storing computer instructions;
• and
• a processor configured to execute the computer instructions to:
• receive a signal from a base station within a flexible subframe;
• determine, based on estimating a correlation between a known reference sequence and a sequence of the received signal in Resource Element (RE) positions, a power of a reference signal for Channel-State-Information (CSI) measurement;
• determine, based on the determined power of the reference signal, whether the reference signal is comprised in the received signal;
• determine CSI for the flexible subframe based on the reference signal after it is determined that the reference signal is comprised in the received signal;
• and
• report the determined CSI to the base station;
• wherein determining of whether a reference signal for CSI measurement is comprised in the received signal may further comprise comparing the estimated correlation with a correlation threshold value;
• and
• wherein in response to that the correlation between the known reference sequence and the sequence of the received signal in RE positions exceeds the correlation threshold value, the UE performs determining of the power of the reference signal for the CSI measurement.

A non-transitory computer-readable medium comprising a computer program code that, when executed by a processor coupled to a User Equipment (UE), causes the UE to perform operations comprising:

• receiving a signal from a base station within a flexible subframe;
• determining, based on estimating a correlation between a known reference sequence and a sequence of the received signal in Resource Element (RE) positions, a power of a reference signal for a Channel-State-Information (CSI) measurement;
• determining, based on the determined power of the reference signal, whether the reference signal is comprised in the received signal;
• determining CSI for the flexible subframe based on the reference signal after it is determined that the reference signal is comprised in the received signal;
• and
• reporting the determined CSI to the base station;
• wherein determining of whether a reference signal for CSI measurement is comprised in the received signal may further comprise comparing the estimated correlation with a correlation threshold value;
• and
• wherein in response to that the correlation between the known reference sequence and the sequence of the received signal in RE positions exceeds the correlation threshold value, the UE performs determining of the power of the reference signal for the CSI measurement.