Signal separation in an orthogonal time frequency space communication system using MIMO antenna arrays
View Patent ↗A device and method for signal separation in an orthogonal time frequency space communication system using MIMO antenna arrays. The communication device includes an antenna arrangement and a receiver. The receiver is configured to receive, from the antenna arrangement, a plurality of pilot signals associated with respective locations in a time-frequency plane wherein the plurality of pilot signals were transmitted from a corresponding plurality of transmit antenna elements. The receiver is further configured to receive signal energy transmitted by the plurality of transmit antenna elements and to measure, based upon the plurality of pilot signals, a plurality of two-dimensional time-frequency coupling channels between the plurality of transmit antenna elements and the antenna arrangement. The receiver is also operative to invert a representation of each of the plurality of two-dimensional time-frequency coupling channels to provide a plurality of inverted channel representations.
1. A communication device, comprising:
an antenna arrangement;
a receiver configured to:
receive, from the antenna arrangement, a plurality of pilot signals associated with respective locations in a time-frequency plane wherein the plurality of pilot signals were transmitted from a corresponding plurality of transmit antenna elements;
receive signal energy transmitted by the plurality of transmit antenna elements;
measure, based upon the plurality of pilot signals, a plurality of two-dimensional time-frequency coupling channels between the plurality of transmit antenna elements and the antenna arrangement; and
invert a representation of each of the plurality of two-dimensional time-frequency coupling channels to provide a plurality of inverted channel representations.
2. The communication device of claim 1 wherein the receiver is further configured to use the plurality of inverted channel representations to separate the signal energy into a plurality of time-frequency planes of information.
3. The communication device of claim 1 further including a transmitter configured to transform a plurality of data elements into a two-dimensionally spread data matrix and to provide, to the antenna arrangement, a data signal modulated in accordance with the spread data matrix.
4. The communication device of claim 3 wherein the transmitter is further configured to pre-encode the plurality of data elements based upon a precoding signal received by the receiver.
5. A communication device, comprising:
an antenna arrangement;
a receiver configured to:
receive, from the antenna arrangement, a pilot signal associated with a location in a time-frequency plane wherein the pilot signal was transmitted from a transmit antenna element;
receive signal energy transmitted by the transmit antenna element;
measure, based upon the pilot signal, a two-dimensional time-frequency coupling channel between the transmit antenna element and the antenna arrangement,
invert a representation of the two-dimensional time-frequency coupling channel to provide an inverted channel representation; and
use the inverted channel representation to separate the signal energy into a time-frequency plane of information.
6. The communication device of claim 5 further including a transmitter configured to transform a plurality of data elements into a two-dimensionally spread data matrix and to provide, to the antenna arrangement, a data signal modulated in accordance with the spread data matrix.
7. The communication device of claim 6 wherein the transmitter is further configured to pre-encode the plurality of data elements based upon a precoding signal received by the receiver.
8. A method, comprising:
providing, by a set of M antennas of a receiver, a set of M received signals wherein the set of M received signals are provided in response to N information signals transmitted by a set of N transmit antennas, where M and N are greater than one;
measuring a plurality of two-dimensional coupling channels existing between the M antennas of the receiver and each of the N transmit antennas;
inverting a representation of each of the plurality of two-dimensional coupling channels to provide a plurality of inverted channel representations; and
separating, using the plurality of inverted channel representations, the M received signals into estimates of the N information signals.
9. The method of claim 8 wherein the measuring includes receiving, from each of the M antennas, a plurality of pilot signals transmitted by the N transmit antennas wherein each of the plurality of pilot signals is associated with a respective location in a time-frequency plane.