Method for obtaining uplink calibration values, calibration method, and corresponding terminal and base station

Terminal (10) for a wireless communication system, adapted to obtain uplink calibration values in order to enable a Base Station, BS (20), having a number of antennas (21a, b) to determine a respective hardware chain value for each antenna of the number of antennas (21a, 21b), comprising

• calculating means (14) for calculating an uplink calibration value for each antenna on the basis of a downlink channel estimate value for each antenna and a normalization value obtained from said downlink channel estimate values, and
• transmitting means (13) for transmitting the calculated uplink calibration value for each antenna to the BS (20).

Base Station, BS (20), having a number of antennas (21a, 21b) divided into a number of groups of antennas, comprising receiving means (22a, 22b) adapted to receive an uplink calibration signal from a terminal, said uplink calibration signal comprising an uplink calibration value for each antenna and a normalization value for each antenna group, and

• processing means (24) adapted to process each received uplink calibration value and each received normalization value into a respective hardware chain value for each antenna of the number of antennas.

Calibration method for determining hardware chain values in a Base Station, BS (20), having a number of antennas (21a, b) grouped in a number of groups, wherein a respective hardware chain value for each antenna of the number of antennas is obtained,

• said method comprising the steps of
• receiving (3), by the BS, an uplink calibration signal from a terminal, said uplink calibration signal comprising an uplink calibration value for each antenna and a normalization value for each group of antennas, and
• processing (4), by the BS, each received uplink calibration value and each received normalization value into a respective hardware chain value for each antenna.