Signal processing in electronic apparatus
AssigneeNokia Corporation
InventorKari Majonen
Life of this patent
Estimating the term…
Abstract
A method, apparatus, and computer program for estimating a rank, i.e. the number of uncorrelated spatial channels, of a radio channel are provided. The rank estimation is carried out by examining mutual proportions of a first eigenvalue and a second eigenvalue of a two-by-two channel matrix representation with a test function including elements of a solution of roots of a quadratic characteristic equation of the two-by-two channel matrix representation, wherein the test function comprises a discriminant of the solution of the roots of the quadratic characteristic equation without a square root operation.
Claims21
A method, comprising:
- calculating a two-by-two channel matrix representation representing properties of a radio channel between a transmission antenna array of a radio transmitter and a reception antenna array of a radio receiver;
- examining mutual proportions of a first eigenvalue and a second eigenvalue of the channel matrix representation with a test function including elements of a solution of roots of a quadratic characteristic equation of the two-by-two channel matrix representation, wherein the test function comprises a discriminant of the solution of the roots of the quadratic characteristic equation without a square root operation;
- and
- determining the number of available spatially parallel communication streams between the transmission antenna array and reception antenna array from the mutual proportions of the eigenvalues.
An apparatus comprising at least one processor and at least one memory including computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus at least to:
- receive information representing properties of a radio channel between a transmission antenna array of a radio transmitter and a reception antenna array of a radio receiver;
- calculate, from the information received, a two-by-two channel matrix representation representing properties of the radio channel;
- examine mutual proportions of a first eigenvalue and a second eigenvalue of the channel matrix representation with a test function including elements of a solution of roots of a quadratic characteristic equation of the two-by-two channel matrix representation, wherein the test function comprises a discriminant of the solution of the roots of the quadratic characteristic equation without a square root operation;
- and
- determine the number of available spatially parallel communication streams between the transmission antenna array and the reception antenna array from the mutual proportions of the eigenvalues.
An apparatus, comprising:
- calculating means for calculating a two-by-two channel matrix representation representing properties of a radio channel between a transmission antenna array of a radio transmitter and a reception antenna array of a radio receiver;
- examining means for examining mutual proportions of a first eigenvalue and a second eigenvalue of the channel matrix representation with a test function including elements of a solution of roots of a quadratic characteristic equation of the two-by-two channel matrix representation, wherein the test function comprises a discriminant of the solution of the roots of the quadratic characteristic equation without a square root operation;
- and
- determining means for determining the number of available spatially parallel communication streams between the transmission antenna array and the reception antenna array from the mutual proportions of the eigenvalues.
A non-transitory computer readable medium having a computer program embodied thereon, the computer program being configured to control a processor to perform:
- calculating a two-by-two channel matrix representation representing properties of a radio channel between a transmission antenna array of a radio transmitter and a reception antenna array of a radio receiver;
- examining mutual proportions of a first eigenvalue and a second eigenvalue of the channel matrix representation with a test function including elements of a solution of roots of a quadratic characteristic equation of the two-by-two channel matrix representation, wherein the test function comprises a discriminant of the solution of the roots of the quadratic characteristic equation without a square root operation;
- and
- determining the number of available spatially parallel communication streams between the transmission antenna array and reception antenna array from the mutual proportions of the eigenvalues.
Dependencies are inferred from the claim text.