Cooperative subspace multiplexing
In a multiuser (MU) multiple antenna system (MAS), a subspace processor is communicatively coupled to a plurality of geographically distributed transceivers by a network. The subspace processor multiplies a plurality of data symbols in each bin of an invertible transform with spatial-processing weights to produce weighted data symbols, which are transmitted from a plurality of geographically distributed transmitters to a plurality of receivers. The spatial-processing weights are generated from channel state information in the MU-MAS to cause a desired signal to be reinforced and at least one undesired signal to be suppressed at each of the plurality of receivers.
1. A method, comprising:
multiplying a plurality of data symbols in each bin of an invertible transform with a plurality of spatial-processing weights to produce weighted data symbols; and
transmitting the weighted data symbols from a plurality of geographically distributed transceivers to a plurality of receivers, wherein the spatial-processing weights cause a desired signal to be reinforced and at least one undesired signal to be suppressed at each of the plurality of receivers.
2. The method of claim 1 , further comprising:
estimating channel state information (CSI) for a propagation environment between the plurality of geographically distributed transceivers and the plurality of receivers; and
generating the spatial processing weights from the CSI, the spatial processing weights providing for a plurality of sub-space channels that are non-interfering channels.
3. The method of claim 2 , wherein estimating CSI further comprises processing a received pilot signal to measure the CSI.
4. The method of claim 2 , wherein generating the spatial processing weights comprises associating each of the plurality of sub-space channels with a different user device.
5. The method of claim 1 , further comprising communicatively coupling the plurality of geographically distributed transceivers to a central processor using at least one of an optical fiber network, a wireline network, and a wireless network.
6. The method of claim 1 , further comprising providing for at least one of power control and synchronization at the plurality of geographically distributed transceivers.
7. The method of claim 1 , further comprising configuring at least one of a user device, a base station, an access point, a relay, and a router to function as a one of the plurality of geographically distributed transceivers.
8. An apparatus, comprising:
a subspace processor; and
a plurality of geographically distributed transceivers of a mobile radio network communicatively coupled to the subspace processor;
wherein the subspace processor generates subspace weights to precode mobile radio network signals transmitted by the plurality of geographically distributed transceivers to a plurality of mobile radio network receivers;
wherein at each mobile radio network receiver, the subspace weights cause a desired signal transmission to be reinforced and at least one undesired signal transmission to be suppressed.
9. The apparatus of claim 8 , wherein the subspace processor is configured to:
estimate channel state information (CSI) for a propagation environment between the plurality of geographically distributed transceivers and the plurality of receivers; and
generate the spatial processing weights from the CSI, the spatial processing weights providing for a plurality of sub-space channels that are non-interfering channels.
10. The apparatus of claim 9 , wherein the subspace processor is configured to process at least one of a pilot signal and a training signal to measure the CSI.
11. The apparatus of claim 9 , wherein the subspace processor is configured to associate each of the plurality of sub-space channels with a different user device.
12. The apparatus of claim 8 , wherein the subspace processor is communicatively coupled to the plurality of geographically distributed transceivers by at least one of an optical fiber network, a wireline network, and a wireless network.
13. The apparatus of claim 8 , wherein the subspace processor is configured to perform at least one of power control and synchronization of the plurality of geographically distributed transceivers.
14. The apparatus of claim 8 , wherein at least one of the plurality of geographically distributed transceivers comprises at least one of a user device, a base station, an access point, a relay, and a router.
15. The apparatus of claim 8 , wherein the subspace processor resides in at least one of the plurality of geographically distributed transceivers.
16. An apparatus, comprising:
at least one processor; and
a non-transitory computer-readable memory communicatively coupled to the processor, the memory including a set of instructions stored therein and executable by the processor for:
multiplying a plurality of data symbols in each bin of an invertible transform with a plurality of spatial-processing weights to produce weighted data symbols; and
transmitting the weighted data symbols from a plurality of geographically distributed transceivers to a plurality of receivers, wherein the spatial-processing weights cause a desired signal to be reinforced and at least one undesired signal to be suppressed at each of the plurality of receivers.
17. The apparatus of claim 16 , wherein the memory further comprises instructions stored therein and executable by the at least one processor for:
estimating channel state information (CSI) for a propagation environment between the plurality of geographically distributed transceivers and the plurality of receivers; and
generating the spatial processing weights from the CSI, the spatial processing weights providing for a plurality of sub-space channels that are non-interfering channels.
18. The apparatus of claim 17 , wherein estimating CSI further comprises processing a received pilot signal to measure the CSI.
19. The apparatus of claim 17 , wherein generating the spatial processing weights comprises associating each of the plurality of sub-space channels with a different user device.
20. The apparatus of claim 16 , wherein the memory further comprises instructions stored therein and executable by the at least one processor for communicatively coupling the plurality of geographically distributed transceivers to a central processor via at least one of an optical fiber network, a wireline network, and a wireless network.
21. The apparatus of claim 16 , wherein the memory further comprises instructions stored therein and executable by the at least one processor for providing for at least one of power control and synchronization at the plurality of geographically distributed transceivers.
22. The apparatus of claim 16 , wherein the memory further comprises instructions stored therein and executable by the at least one processor for configuring at least one of a user device, a base station, an access point, a relay, and a router to function as a one of the plurality of geographically distributed transceivers.
23. The apparatus of claim 16 , wherein the memory further comprises instructions stored therein and executable by the at least one processor to operate as a software-defined radio.
24. The apparatus of claim 16 , wherein at least one of the memory and the at least one processor reside on a plurality of devices communicatively coupled together.
25. The apparatus of claim 16 , wherein at least one of the memory and the at least one processor resides on at least one of the plurality of geographically distributed transceivers.