Optimization of interlayer handovers in multilayer wireless communication networks

1. A method for parameter optimization of at least one interlayer handover in a multilayer wireless cellular communication network, the method comprising:

retrieving performance information for the communication network, wherein the communication network comprises a macrolayer that presents at least one macrocell and a microlayer that presents at least one microcell;

averaging the retrieved performance information for the communication network over a predetermined period of time;

determining based on the averaged performance information whether optimization of the communication network is required; and

in response to determining that optimization of the communication network is required, optimizing the interlayer handover by capturing a current set of configuration parameters for the interlayer handover, generating a new set of configuration parameters for the interlayer handover based on the retrieved performance information and the current set of configuration parameters by relaxing a threshold condition for entering the microlayer when congestion in the macrocell is detected and congestion or quality degradation are not detected in the microcell, and applying the new set of configuration parameters to the communication network.

2. The method of claim 1 , wherein the multilayer wireless cellular communication network comprises a plurality of cells and a plurality of layers, and wherein the retrieving, averaging, determining, and optimizing operations are performed for each cell of each layer of the communication network.

3. The method of claim 2 , wherein the performance information comprises data identifying one or more Key Performance Indicators (KPIs) of the communication network.

4. The method of claim 3 , wherein the performance information comprises data identifying one or more reported alarm events in the communication network, and wherein generating a new set of configuration parameters for the interlayer handover comprises generating a new set of configuration parameters for the interlayer handover based on the data identifying one or more reported alarm events in the communication network.

5. The method of claim 4 , wherein the communication network further comprises an Operation and Support System (OSS), and wherein retrieving performance information for the communication network comprises retrieving the performance information from the OSS.

6. The method of claim 5 , wherein the interlayer handover is operative to hand over a wireless communication from a first layer to a second layer of the communication network.

7. The method of claim 6 , wherein the interlayer handover is triggered when at least one threshold condition is fulfilled.

8. The method of claim 7 , wherein the threshold condition is defined by the current set of configuration parameters.

9. The method of claim 8 , wherein the KPIs comprise one or more of a carrier-to-carrier interference ratio (C/I), a received signal level, a user speed level, or a path loss indicator, and wherein the threshold condition is defined by at least one of the KPIs.

10. The method of claim 9 , wherein the communication network comprises at least two layers operating at different frequencies and the interlayer handover is a load based inter-frequency handover, and wherein generating a new set of configuration parameters for the interlayer handover comprises monitoring a load in the two layers and adjusting a handover load threshold condition in order to achieve a balanced distribution of the load among the two layers.

11. The method of claim 1 , wherein generating a new set of configuration parameters for the interlayer handover based on the retrieved performance information and the current set of configuration parameters comprises increasing a threshold condition for entering the microlayer when quality or congestion problems in the microcell are not detected.

12. A system for parameter optimization of at least one interlayer handover in a multilayer wireless cellular communication network comprising a macrolayer that presents at least one macrocell and a microlayer that presents at least one microcell, the system comprising:

a tuning system configured to

retrieve information about the network performance,

average the retrieved information about the network performance over a predetermined period of time,

receive a current set of configuration parameters for the interlayer handover that are captured from the network,

determine a new set of configuration parameters for the interlayer handover according to at least one criterion, on the basis of the retrieved information about the network performance, and the captured current set of configuration parameters for the interlayer handover by relaxing a threshold condition for entering the microlayer when congestion in the macrocell is detected and congestion or quality degradation are not detected in the microcell, and

to cause the determined new set of configuration parameters for the interlayer handover to be applied to the communication network.

13. The system of claim 12 , wherein the information about the network performance comprises one or more Key Performance Indicators (KPIs) of the communication network.

14. The system of claim 13 , wherein the information about the network performance comprises data identifying one or more reported alarm events in the communication network.

15. The system of claim 14 , wherein the interlayer handover is operative to hand over a wireless communication from a first layer to a second layer of the communication network.

16. The system of claim 15 , wherein the interlayer handover is triggered when at least one threshold condition is fulfilled, the threshold condition being defined by the captured current set of configuration parameters.

17. The system of claim 16 , wherein the KPIs comprise one or more of a carrier-to-carrier interference ratio (C/I), a received signal level, a user speed level, or a path loss indicator, and wherein the threshold condition is defined by at least one of the KPIs.

18. A computer-readable storage medium that is not a signal comprising computer-executable instructions stored thereon, which, when executed by a computer, cause the computer to:

retrieve performance information for a communication network comprising a macrolayer that presents at least one macrocell and a microlayer that presents at least one microcell;

take an average of the retrieved performance information for the communication network over a predetermined period of time;

determine based on the averaged performance information whether optimization of the communication network is required; and

in response to determining that optimization of the communication network is required, optimize an interlayer handover by capturing a current set of configuration parameters for the interlayer handover, generating a new set of configuration parameters for the interlayer handover based on the retrieved performance information and the current set of configuration parameters by relaxing a threshold condition for entering the microlayer when congestion in the macrocell is detected and congestion or quality degradation are not detected in the microcell, and applying the new set of configuration parameters to the communication network.