Apparatus and method for determining an effective channel and feedback information

A method for determining feedback information, comprising:

• selecting more than one basic column vectors for determining a preceding matrix;
• calculating products of channel row vectors and the basic column vectors;
• determining, via a processor, an effective channel or a Hermitian matrix of an effective channel by using the products;
• calculating metric values to which each codebook index and rank correspond based on the Hermitian matrix of the effective channel;
• and
• determining that the codebook index and rank to which a maximal metric value corresponds as the feedback information fed back to a transmission side;
• wherein, when the rank is 3, the step of calculating metric values to which each codebook index and rank correspond based on the Hermitian matrix of the effective channel comprises:
• performing row transform and column transform on Hermitian matrixes of effective channels of two codebook indices, so that the transformed Hermitian matrixes of the effective channels have identical submatrixes located at the upper left and with a dimension of 2×2;
• executing jointly inversion to the transformed Hermitian matrixes of the effective channels of the two codebook indices by using the block inversion lemma of Hermitian matrix, so as to obtain respective inversion matrixes;
• determining diagonal elements in the inversion matrixes of the Hermitian matrixes of the effective channels by using the obtained inversion matrixes;
• and
• calculating the metric values by using the diagonal elements.

An apparatus for determining feedback information, comprising:

• a second processor, for determining a Hermitian matrix of an effective channel, wherein the second processor comprising:
• a first selector for selecting more than one basic column vectors for determining a precoding matrix;
• a first calculator for calculating products of channel row vectors and the basic column vectors;
• and
• a first processor for determining the effective channel or a Hermitian matrix of the effective channel by using the products;
• wherein the apparatus further comprising:
• a second calculator for calculating metric values to which each codebook index and rank correspond based on the Hermitian matrix of the effective channel;
• and
• a second selector for selecting the codebook index and rank to which a maximal metric value corresponds as the feedback information fed back to a transmission side;
• wherein when the rank is 3, the second calculator comprises:
• a third processor for performing row transform and column transform on Hermitian matrixes of effective channels of two codebook indices, so that the transformed Hermitian matrixes of the effective channels have identical submatrixes located at the upper left and with a dimension of 2×2;
• a third calculator for executing jointly inversion to the transformed Hermitian matrixes of the effective channels of the two codebook indices by using the block inversion lemma of Hermitian matrix, so as to obtain respective inversion matrixes;
• a fourth processor for determining diagonal elements in the inversion matrixes of the Hermitian matrixes of the effective channels by using the obtained inversion matrixes;
• and
• a fourth calculator for calculating the metric values by using the diagonal elements.

An apparatus for determining feedback information, comprising:

• a second processor for determining a Hermitian matrix of an effective channel, wherein the second processor comprising:
• a first selector for selecting more than one basic column vectors for determining a precoding matrix;
• a first calculator for calculating products of channel row vectors and the basic column vectors;
• and
• a first processor for determining the effective channel or a Hermitian matrix of the effective channel by using the products;
• wherein the apparatus further comprising:
• a second calculator for calculating metric values to which each codebook index and rank correspond based on the Hermitian matrix of the effective channel;
• and
• a second selector for selecting the codebook index and rank to which a maximal metric value corresponds as the feedback information fed back to a transmission side;
• wherein when the rank is 4 and the number of the codebook indices is 16, the second calculator comprises:
• a third processor for dividing the codebook indices into 5 groups, wherein in each group of codebook indices, the diagonal elements in the inversion matrixes of the Hermitian matrixes of the effective channel of each of the codebook indices belong to the same set and are different orders;
• and
• a third calculator for calculating the inversion matrix of the Hermitian matrix of the effective channel to which each of the codebook indices in each group corresponds;
• wherein the calculating the inversion matrix for one group of codebook indices comprises:
• calculating the inversion matrix to which one codebook index in the one group of codebook indices corresponds;
• and
• obtaining the inversion matrixes to which other codebook indices in the one group of codebook indices correspond, by using the relationship between the inversion matrix to which the one codebook index corresponds and the inversion matrixes of the Hermitian matrixes of the effective channels to which the other codebook indices in the one group of codebook indices correspond, and using the inversion matrix to which the one codebook index corresponds.

An apparatus for determining feedback information, comprising:

• a second processor, for determining a Hermitian matrix of an effective channel, wherein the second processor comprising:
• a first selector for selecting more than one basic column vector for determining a precoding matrix;
• a first calculator for calculating products of channel row vectors and the basic column vectors;
• and
• a first processor for determining the effective channel or a Hermitian matrix of the effective channel by using the products;
• wherein if there is a common computational factor in the multiplication operation of the channel row vectors and the basic column vectors, there first calculator comprises:
• a second calculator for calculating common computational factor;
• and
• a third calculator for calculating the products of the channel row vectors and the basic column vectors by using common computational factor;
• wherein the apparatus further comprising:
• a fourth calculator for calculating metric values to which each codebook index and rank correspond based on the Hermitian matrix of the effective channel;
• and
• a second selector for selecting the codebook index and rank to which a maximal metric value corresponds as the feedback information fed back to a transmission side.

A method for determining feedback information, comprising:

• selecting more than one basic column vectors for determining a precoding matrix;
• calculating products of channel row vectors and the basic column vectors;
• determining, via a processor, an effective channel or a Hermitian matrix of an effective channel by using the products;
• calculating metric values to which each codebook index and rank correspond based on the Hermitian matrix of the effective channel;
• and
• determining that the codebook index and rank to which a maximal metric value corresponds as the feedback information fed back to a transmission side;
• wherein, when the rank is 4 and the number of the codebook indices is 16, the step of calculating metric values to which each codebook index and rank correspond based on the Hermitian matrix of the effective channel comprises:
• dividing the codebook indices into 5 groups, wherein in each group of codebook indices, the diagonal elements in the inversion matrixes of the Hermitian matrixes of the effective channel of each of the codebook indices belong to the same set and are different orders;
• and
• calculating the inversion matrix of the Hermitian matrix of the effective channel to which each of the codebook indices in each group corresponds;
• wherein the calculating the inversion matrix for one group of codebook indices comprises:
• calculating the inversion matrix to which one codebook index in the one group of codebook indices corresponds;
• and
• obtaining the inversion matrixes to which other codebook indices in the one group of codebook indices correspond, by using the relationship between the inversion matrix to which the one codebook index corresponds and the inversion matrixes of the Hermitian matrixes of the effective channels to which the other codebook indices in the one group of codebook indices correspond, and using the inversion matrix to which the one codebook index corresponds.

An apparatus for determining an effective channel, comprising:

• a first selector component for selecting more than one basic column vector for determining a precoding matrix;
• a first calculator component for calculating products of channel row vectors and the basic column vectors;
• and
• a first processor component for determining the effective channel or a Hermitian matrix of the effective channel by using the products;
• wherein, if there is a common computational factor in the multiplication operation of the channel row vectors and the basic column vectors, the first calculator component comprises:
• a second calculator component for calculating the common computational factor;
• and
• a third calculator component for calculating the products of the channel row vectors and the basic column vectors by using the common computational factor.