Minimizing interference in a heterogeneous wireless network

• US 10,165,578 B1
• Filed: 11/08/2016
• Issued: 12/25/2018
• Est. Priority Date: 11/08/2016
• Status: Active Grant

• Current Assignee: Sprint Spectrum LLC (Deutsche Telekom AG)
• Original Assignee: Sprint Spectrum LP (Deutsche Telekom AG)
• Inventors: Zappaterra, Luca, Naim, Muhammad Ahsan, Zhou, Yu
• Primary Examiner(s): Han, Clemence S
• Application Number:
  US15/345,798
• Time in Patent Office: 777 Days
• CPC Class Codes: H04J 11/0056 Inter-base station aspects
• CPC Class Codes: H04W 16/32 Hierarchical cell structures

Abstract

Minimizing interference in a heterogeneous wireless network includes determining a group of potentially interfering access nodes from among the plurality of neighboring access nodes, based on reference signals transmitted from each of the plurality of neighboring access nodes, and communicating additional signal information between each access node within the group of potentially interfering access nodes. The additional signal information is associated with signals transmitted from said each access node within the group. Each access node within the group performs interference minimization based on the additional signal information, thereby enabling full-duplex operation.

Claims

1. A method for minimizing interference in a heterogeneous wireless network, the method comprising:

receiving, at a first access node, a reference signal from a neighboring access node within a defined portion of a transmission frame, wherein the neighboring access node is one of a plurality of neighboring access nodes, each of which is configured to schedule a corresponding plurality of reference signals using resources within the defined portion of the transmission frame;

based on the reference signal, adding the neighboring access node to a potential interferer group associated with the first access node;

determining a potential interference based on additional signal information received from the neighboring access node; and

processing a first signal at the first access node based on the potential interference.

2. The method of claim 1, wherein the reference signal is received periodically in every subsequent transmission frame.

3. The method of claim 1, further comprising adding one or more of the plurality of neighboring access nodes to the potential interferer group based on the corresponding plurality of reference signals.

4. The method of claim 1, wherein the additional signal information comprises at least one of a modulation scheme, a coding scheme, and a resource allocation.

5. The method of claim 4, wherein determining the potential interference comprises generating a second signal based on the additional signal information.

6. The method of claim 5, wherein processing the first signal based on the potential interference comprises subtracting the second signal from the first signal.

7. The method of claim 1, wherein the additional signal information is received via one or more of a direct connection with the neighboring access node or a low-latency backhaul connection with the heterogeneous wireless network.

8. A system for minimizing interference in a heterogeneous wireless network, the system comprising:

a plurality of neighboring access nodes configured to schedule a corresponding plurality of reference signals using resources within a defined portion of a transmission frame;

a first access node from among the plurality of neighboring access nodes, the first access node being configured to;

broadcast a reference signal within the defined portion of the transmission frame; and

a second access node from among the plurality of neighboring access nodes, the second access node being configured to;

receive the reference signal;

determine that the first access node is among a group of potentially interfering access nodes from among the plurality of neighboring access nodes; and

minimize potential interference caused by the first access node to signals received at the second access node.

9. The system of claim 8, wherein the second access node is further configured to determine that the first access node is among the group of potentially interfering access nodes based in part on a signal strength of the reference signal measured at the second access node.

10. The system of claim 9, wherein the second access node is further configured to determine that the first access node is among the group of potentially interfering access nodes based in part on the signal strength of the reference signal measured at the second access node being within a predetermined range.

11. The system of claim 8, wherein the second access node is further configured to transmit a notification to the first access node indicating that the first access node is among the group of potentially interference access nodes.

12. The system of claim 11, wherein the first access node is configured to transmit additional signal information to the second access node upon receiving the notification, wherein the additional signal information comprises at least one of a modulation scheme, a coding scheme, and a resource allocation associated with signals transmitted from the first access node.

13. The system of claim 12, wherein the second access node is configured to minimize potential interference caused by the first access node to the signals received at the second access node based in part on the additional signal information.

14. A processing node for minimizing interference in a heterogeneous wireless network, the processing node being configured to perform operations comprising:

instructing a plurality of neighboring access nodes to schedule a corresponding plurality of reference signals using resources within a predefined portion of a transmission frame;

determining a group of potentially interfering access nodes from among the plurality of neighboring access nodes, based on the reference signals transmitted from each of the plurality of neighboring access nodes; and

communicating additional signal information between each access node within the group of potentially interfering access nodes, the additional signal information being associated with signals transmitted from said each access node within the group,

wherein each access node within the group performs interference minimization based on the additional signal information.

15. The processing node of claim 14, wherein determining the group is based on a signal strength of the reference signals transmitted during the predefined portion meeting a threshold.

16. The processing node of claim 14, wherein the additional signal information is communicated between each access node in the group via a direct connection between said each access node.

17. The processing node of claim 14, wherein the additional signal information is communicated between each access node in the group via a low-latency backhaul connection of said each access node.