Wireless receiver unit, spatial phase corrector circuit for amplitude modulation and method therefor

A spatial phase corrector circuit for a wireless receiver unit having a plurality of antennas, the spatial phase corrector circuit configured to receive at least a first amplitude modulated, AM, frequency down-converted signal from a first receiver via a first receiver path and a second AM frequency down-converted signal from a second receiver via a second receiver path, the spatial phase corrector circuit comprising:

• a computation circuit configured to generate a spatial-covariance matrix, SCM, of the received first frequency down-converted AM signal and second frequency down-converted AM signal;
• a signal decomposition circuit coupled to the computation circuit and configured to generate an Eigen-value decomposition, EVD, of the SCM of the received first frequency down-converted AM signal and second frequency down-converted AM signal;
• and
• a processor coupled to the signal decomposition circuit and configured to analyse the EVD of the SCM of the received first frequency down-converted AM signal and second frequency down-converted AM signal and select and output a principal Eigen-vector that is representative of at least a first weight and a second weight;
• and
• an output for outputting the principal Eigen-vector to a combiner for applying the first weight to the received first AM signal and the second weight to the second AM signal thereby coherently combining the received AM-signals.

A method of spatial phase correction for a wireless receiver unit having a plurality of antennas, the method comprising:

• receiving at least a first frequency down-converted amplitude modulated, AM, signal from a first receiver via a first receiver path and a second frequency down-converted AM signal from a second receiver via a second receiver path that is a phase-shifted version of the first frequency down-converted AM signal;
• generating a spatial-covariance matrix, SCM, of the received first AM signal and second AM signal;
• generating an Eigen-value decomposition, EVD, of the SCM of the received first frequency down-converted AM signal and second frequency down-converted AM signal;
• and
• analysing the EVD of the SCM of the received first frequency down-converted AM signal and second frequency down-converted AM signal and selecting a principal Eigen-vector that is representative of at least a first weight and a second weight;
• and
• applying the first weight to the first frequency down-converted AM signal and applying the second weight to the second frequency down-converted AM signal;
• and
• coherently combining and outputting a weight-applied frequency down-converted AM signal.