Data detection in MIMO systems with demodulation and tracking reference signals
What is disclosed is a method for wireless communication comprising receiving a wireless communication via a receiver of the mobile communication device, deriving a demodulation reference signal from a first plurality of symbols of the wireless communication; creating a channel estimation matrix using the demodulation reference signal; inverting the channel estimation matrix to obtain a channel pseudo-inverse matrix; deriving a tracking reference signal from a second plurality of symbols of the wireless communication; calculating a phase shift for one or more additional symbols based on the tracking reference signal; determining a corrected channel pseudo-inverse matrix for the one or more additional symbols by adjusting the channel pseudo-inverse matrix according to the calculated phase shift; and controlling the receiver to accomplish data detection using the corrected channel pseudo-inverse matrix on one or more orthogonal frequency division multiplexing subcarriers.
1. A method for performing MIMO detection in a mobile communication device, the method comprising:
receiving on a plurality of asynchronous receive antennas a wireless communication comprising a demodulation reference signal and a tracking reference signal;
calculating from the received wireless communication receive-specific phase shifts;
generating a channel estimation matrix based on the demodulation reference signal and the receive-specific phase shifts;
inverting the channel estimation matrix to obtain a channel pseudo-inverse matrix;
calculating from the received tracking reference signal first transmit-specific phase shifts of the asynchronous transmit antennas;
correcting the channel pseudo-inverse matrix for each of the plurality of receive antennas for a symbol within a subframe according to the calculated first transmit-specific phase shifts and the receive-specific phase shifts;
calculating from the received tracking reference signal second transmit-specific phase shifts for the plurality of asynchronous receive antennas; and
correcting the channel pseudo-inverse matrix for each of the plurality of asynchronous receive antennas for a subsequent symbol within the subframe according to the second transmit-specific phase shifts and the receive-specific phase shifts.
2. The method of claim 1 , wherein the wireless communication is received on a multiple-input and multiple-output network.
3. The method of claim 1 , wherein a first dimension of the channel estimate matrix corresponds to a quantity of receive antennas, and a second dimension of the channel estimate matrix corresponds to a quantity of transmit antennas.
4. The method of claim 1 , wherein obtaining the channel pseudo-inverse matrix further comprises isolating each of a plurality of encoded signal data symbols from the wireless communication based on the channel estimation matrix.
5. The method of claim 1 , further comprising using the generated channel estimation matrix to perform a MIMO detection to estimate the symbols transmitted.
6. The method of claim 1 , wherein the tracking reference signal is a Phase Noise Compensation Reference Signal.
7. The method of claim 1 , further comprising adjusting the channel pseudo-inverse matrix by calculating a Hadamard product of the channel pseudo-inverse matrix and the generated tracking reference signal.
8. The method of claim 1 , further comprising using a method of matrix decomposition to invert the channel estimation matrix to obtain a channel pseudo-inverse matrix.
9. The method for performing MIMO detection in a mobile communication device of claim 1 , further comprising receiving the wireless communication from a plurality of asynchronous transmit antennas; and wherein the transmit-specific phase shifts are transmit-specific phase shifts corresponding to the plurality of asynchronous transmit antennas.
10. The method of claim 5 , further comprising performing the MIMO detection with a zero-forcing equalizer algorithm.
11. The method of claim 5 , further comprising performing the MIMO detection with a minimum mean square error equalizer.
12. The method of claim 8 , further comprising the method of matrix decomposition being QR Decomposition.
13. The method of claim 8 , further comprising the method of matrix decomposition being Lower-Upper Decomposition.
14. The method of claim 8 , further comprising the method of matrix decomposition being a Cholesky decomposition.
15. The method of claim 8 , further comprising the method of matrix decomposition being LDL Decompensation.
16. The method of claim 8 , further comprising the method of matrix decomposition being Eigenvalue Decompensation.
17. The method of claim 8 , further comprising the method of matrix decomposition being Singular Value Decompensation.
18. A processing circuit arrangement for a wireless communication, said processing circuit arrangement comprising a transceiver, configured to receive on a plurality of asynchronous receive antennas and from a plurality of asynchronous transmit antennas a wireless communication comprising a demodulation reference signal and a tracking reference signal;
a signal processing circuit configured to calculate from the received wireless communication receive-specific phase shifts of the asynchronous receive antennas;
generate a channel estimation matrix based on the demodulation reference signal and the receive-specific phase shifts; and invert the channel estimation matrix to obtain a channel pseudo-inverse matrix;
a phase calculation circuit configured to calculate from the received tracking reference signal first transmit-specific phase shifts of the asynchronous transmit antennas;
correct the channel pseudo-inverse matrix for each of the plurality of asynchronous receive antennas using the first transmit-specific phase shifts and the receive-specific phase shifts; and calculate from the received tracking reference signal second transmit-specific phase shifts for the plurality of asynchronous receive antennas; and
correct the channel pseudo-inverse matrix for each of the plurality of receive antennas for a subsequent symbol within the subframe according to the second transmit-specific phase shifts and the receive-specific phase shifts.
19. The processing circuit arrangement of claim 18 , further comprising the phase calculation circuit rotating the channel pseudo-inverse matrix based on a plurality of calculated phase shifts to obtain a plurality of corrected channel estimation matrices.