Devices, methods and computer programs for wireless communication with multiple-access
A network node device includes a radio transceiver configured to receive a data sequence from a plurality of user equipments (UEs) over first and second sets of resource elements, wherein the first set of resource elements is mapped non-orthogonally and the second set is mapped orthogonally. The network node device further comprises a processor configured to determine channel vectors based at least in part on the data sequence received over the first set of resource elements or over the second set of resource elements, and to utilize the data sequence as received over the second set of resource elements to associate the determined channel vectors with each of the plurality of UEs.
1. A network node device, comprising:
a radio transceiver configured to receive, from a plurality of user equipments (UEs), a data sequence over a first set of resource elements and a second set of resource elements, wherein the first set of resource elements is mapped non-orthogonally and the second set of resource elements is mapped orthogonally; and
a processor configured to:
determine channel vectors based at least in part on the data sequence received over the first set of resource elements or the second set of resource elements, and
associate, by utilizing the data sequence received over the second set of resource elements, the determined channel vectors with each of the plurality of UEs,
wherein the processor is configured to determine channel vectors based additionally on a scaled covariance matrix of the data sequence received over at least one resource element of the first set of resource elements and the second set of resource elements, determine eigenvalues and eigenvectors of the determined scaled covariance matrix, and scale the eigenvectors to obtain, as the determined channel vectors, a candidate set of channel vectors.
2. The network node device according to claim 1 , wherein the processor is configured to associate the determined channel vectors with each of the plurality of UEs by determining correlations between the data sequence received over the second set of resource elements and the channel vectors in the obtained candidate set of channel vectors.
3. The network node device according to claim 1 , wherein the processor is configured to associate the determined channel vectors with each of the plurality of UEs by:
determining normalized average received power of the data sequence received over the second set of resource elements, and
selecting a channel vector in the obtained candidate set of channel vectors with an eigenvalue closest to the determined normalized average received power.
4. The network node device according to claim 1 , wherein the processor is further configured to determine a total number of resource elements in the first set of resource elements and the second set of resource elements based on radio channel coherence time and radio channel coherence bandwidth.
5. The network node device according to claim 4 , wherein the processor is further configured to:
determine a number of resource elements in the second set of resource elements as a sum of uplink data layers transmitted from each of the plurality of UEs, and
determine a number of resource elements in the first set of resource elements as a difference between the total number of resource elements and the number of resource elements in the second set of resource elements.
6. The network node device according to claim 1 , wherein the processor is further configured to cause the transceiver to send information about determined first and second sets of resource elements to the plurality of UEs.
7. The network node device according to claim 1 , wherein the processor is further configured to determine the first set of resource elements and the second set of resource elements based on information stored in the network node device.
8. A method, comprising:
receiving, by a network node device, a data sequence from a plurality of user equipments (UEs) over a first set of resource elements and a second set of resource elements, wherein the first set of resource elements is mapped non-orthogonally and the second set of resource elements is mapped orthogonally;
determining, by the network node device based at least in part on the data sequence received over the first set of resource elements or the second set of resource elements, channel vectors; and
associating, by the network node device by utilizing the data sequence received over the second set of resource elements, the determined channel vectors with each of the plurality of UEs,
wherein determining the channel vectors is based on a scaled covariance matrix of the data sequence received over at least one of the first set of resource elements and the second set of resource elements, and
wherein determining the channel vectors includes determining eigenvalues and eigenvectors of the scaled covariance matrix and scaling the eigenvectors to obtain a candidate set of channel vectors.
9. The method according to claim 8 , wherein associating the determined channel vectors with each of the plurality of UEs includes determining a normalized average received power of the data sequence received over the second set of resource elements, and selecting a channel vector in the obtained candidate set of channel vectors with an eigenvalue closest to the determined normalized average received power.
10. The method according to claim 8 , further comprising:
determining a total number of resource elements in the first set of resource elements and the second set of resource elements based on radio channel coherence time and radio channel coherence bandwidth.
11. The method of claim 8 , wherein associating the determined channel vectors with each of the plurality of UEs includes determining correlations between the data sequence received over the second set of resource elements and the channel vectors in the obtained candidate set of channel vectors.
12. The method of claim 11 , further comprising:
determining a number of resource elements in the second set of resource elements as a sum of uplink data layers transmitted from each of the plurality of UEs, and
determining a number of resource elements in the first set of resource elements as a difference between the total number of resource elements and the number of resource elements in the second set of resource elements.
13. The method of claim 8 , further comprising sending information about determined first and second sets of resource elements to the plurality of UEs.
14. The method of claim 8 , further comprising determining the first set of resource elements and the second set of resource elements based on information stored in the network node device.
15. A computer program product, comprising:
a non-transitory computer-readable medium storing computer executable instructions, wherein the instructions comprise instructions for:
receiving, by a network node device, a data sequence from a plurality of user equipments (UEs) over a first set of resource elements and a second set of resource elements, wherein the first set of resource elements is mapped non-orthogonally and the second set of resource elements is mapped orthogonally;
determining, by the network node device, channel vectors based at least in part on the data sequence received over the first set of resource elements or the second set of resource elements; and
associating, by the network node device by utilizing the data sequence received over the second set of resource elements, to associate the determined channel vectors with each of the plurality of UEs,
wherein determining the channel vectors is based on a scaled covariance matrix of the data sequence received over at least one of the first set of resource elements and the second set of resource elements, and
wherein determining the channel vectors includes determining eigenvalues and eigenvectors of the scaled covariance matrix and scaling the eigenvectors to obtain a candidate set of channel vectors.
16. The computer program product of claim 15 , wherein the instructions comprise instructions for associating the determined channel vectors with each of the plurality of UEs by determining correlations between the data sequence received over the second set of resource elements and the channel vectors in the obtained candidate set of channel vectors.
17. The computer program product of claim 15 , wherein the instructions comprise instructions for associating the determined channel vectors with each of the plurality of UEs by:
determining normalized average received power of the data sequence received over the second set of resource elements, and
selecting a channel vector in the obtained candidate set of channel vectors with an eigenvalue closest to the determined normalized average received power.
18. The computer program product of claim 15 , wherein the instructions comprise instructions for determining a total number of resource elements in the first set of resource elements and the second set of resource elements based on radio channel coherence time and radio channel coherence bandwidth.
19. The computer program product of claim 18 , wherein the instructions comprise instructions for:
determining a number of resource elements in the second set of resource elements as a sum of uplink data layers transmitted from each of the plurality of UEs, and
determining a number of resource elements in the first set of resource elements as a difference between the total number of resource elements and the number of resource elements in the second set of resource elements.
20. The computer program product of claim 15 , wherein the instructions comprise instructions for sending information about determined first and second sets of resource elements to the plurality of UEs.
21. The computer program product of claim 15 , wherein the instructions comprise instructions for determining the first set of resource elements and the second set of resource elements based on information stored in the network node device.