Method and apparatus for transmitting and receiving beamforming matrix
View Patent ↗The present disclosure provides a method and apparatus for transmitting the beamforming matrix. The method includes calculating the maximum value m v (k) of the real part and imaginary part of the elements in subcarrier's beamforming matrix; carrying out a M bits quantization to m v (k) and obtaining the quantization amplitude M v (k), calculating the linear part M v lin (k) of M v (k); carrying out a respectively N b bits quantization to the real part and imaginary part of every element in V(k) by M v lin (k), and obtaining the quantized beamforming matrix V q (k); N b is positive integer; transmitting said quantization amplitude M v (k) and said quantized beamforming matrix V q (k).
1. A method for transmitting a beamforming matrix of a subcarrier on a channel of a Multiple Input Multiple Output (MIMO) channel of a MIMO system by a transmitter in response to a feedback request from a receiver for obtaining channel information in the MIMO system, comprising:
determining, by the transmitter, a maximum value m v (k) of a real part and an imaginary part of elements in a subcarrier's beamforming matrix V(k);
determining, by the transmitter, an M bits quantization of m v (k);
determining, by the transmitter, a quantization amplitude M v (k), M being a positive integer, wherein no division calculation is performed on m v (k) to determine M v (k);
determining, by the transmitter, a linear part M v lin (k) of M v (k), wherein no division calculation is performed on m v (k) to determine the linear part M v lin (k) of M v (k);
determining, by the transmitter, a N b bits quantization of a real part and imaginary part of every element in V(k) by M v lin (k);
determining, by the transmitter, a quantized beamforming matrix V q (k), N b being a positive integer, wherein
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V (m,l) (k) representing an element in V(k); V (m,l) q(R) representing a real part of quantized V (m,l) (k); V (m,l) q(I) representing an imaginary part of quantized V (m,l) (k); m being a row position reference, l being a column position reference; sign(V (m,l) (k)) representing a polarity symbols of V (m,l) (k);
min(2 N b −1 −1,
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round representing a rounding operation;
“| |” representing an absolute operation; and c being a positive real number; and
transmitting, by the transmitter, said quantization amplitude M v (k) and said quantized beamforming matrix V q (k).
2. The method of claim 1 , wherein the M bits quantization of m v (k) is determined as follows:
M v ( k )=min{2 M −1,ƒ( g ( m v ( k )))};
M v (k) being a minimum value of (2 M −1) and ƒ(g(m v (k))); ƒ(g(m v (k))) representing an integral function of a result of g(m v (k)); g(m v (k)) mapping a linear m v (k) from an interval of natural numbers to an interval of logarithmic numbers, M being a positive integer.
3. The method of claim 2 , wherein
g( v (k))=a lo b (m v (k)c), a, b, c being positive real numbers.
4. The method of claim 3 , wherein the linear part M v lin (k) of M v (k) is determined by an equation: M v lin (k)=b M v (k)/a .
5. The method of claim 3 , wherein a equals to 14.42, b equals 2, c equals to 0.45; or a equals to 47.9, b equals to 10, c equals to 0.45.
6. The method of claim 1 , wherein M is greater than 1.
7. The method of claim 6 , wherein M is equal to 3.
8. The method of claim 1 , wherein the value of N b is one of 4, 5, 6, 8, 10, or 12.
9. The method of claim 1 , further comprising:
transmitting said quantization amplitude M v (k) of each subcarrier in a set of subcarriers and said quantized beamforming matrix V q (k) together.
10. A method for a receiver receiving a beamforming matrix of a subcarrier on a Multiple Input Multiple Output (MIMO) channel of a MIMO system from a transmitter to obtain channel information in the MIMO system when the receiver initiates a feedback request, comprising:
receiving, by the receiver, a quantized subcarrier's beamforming matrix V q (k) and a quantization amplitude M v (k), wherein
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V (m,l) (k) representing an element in V(k); V (m,l) q(R) representing a real part of quantized V (m,l) (k); V (m,l) q(I) representing an imaginary part of quantized V (m,l) (k);
m being a row position reference, l being a column position reference;
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representing a minimum value of (2 N b −1 −1) and
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round representing a rounding operation; “| |” representing an absolute operation; N b being a positive integer and c being a positive real number;
recovering, by the receiver, an amplitude value r(k) according to M v (k), including carrying out a reverse process based on a method for quantizing M v (k), wherein no division calculation is performed on m v (k) for quantizing M v (k);
scaling, by the receiver, a real part and an imaginary part of every element in V q (k) according to r(k);
recovering, by the receiver, a beamforming matrix {tilde over (v)}(k) of a subcarrier; and
calculating, by the receiver, the subcarrier's precoding matrix Q k according to {tilde over (V)}(k).