Robust beam tracking and data communication in millimeter-wave mobile networks

1. A method for robust beam tracking and data communication, comprising:

dividing, by a base station, time into frames each having two phases, a location probing phase and a data communication phase;

determining a steady state analysis of the performance of beam tracking by the base station;

formulating an optimization problem to obtain optimal frame structure maximizing steady state average throughput;

in the location probing phase, using a fractional search policy to localize at least one mobile device by transmitting multiple probing packets over different time-slots and updating information about a location of the at least one mobile device; and

in the data communication phase, communicating with the at least one mobile device while expanding a beamwidth to compensate for possible mobility of the at least one mobile device.

2. The method as recited in claim 1 , wherein details of a mobility model of the at least one mobile device are not available to the base station.

3. The method as recited in claim 1 , wherein updating the information about the location of the at least one mobile device comprises updating the information about the location of the at least one mobile device based on the feedback from the at least one mobile device.

4. The method as recited in claim 1 , further comprising obtaining an optimal data communication duration using quasi-concave programming.

5. The method as recited in claim 1 , wherein an optimal location probing duration of one timeslot is used for location probing.

6. The method as recited in claim 1 , further comprising:

estimating a maximum user velocity and a distance between the at least one mobile device and the base station using at least one of global positioning system (GPS) or low frequency channels.

7. The method as recited in claim 1 , further comprising:

determining an angular uncertainty region (AUR) on a location of the at least one mobile device; and

matching a transmission pattern to the AUR.

8. The method as recited in claim 1 , further comprising:

localizing the at least one mobile user intermittently to enable use of predetermined narrow beams while maintaining a connection to a predetermined reliability.

9. The method as recited in claim 1 , further comprising:

in the location probing phase, at a beginning of each time-slot, transmitting a probing packet while matching an angular coverage region to a fraction of an angular uncertainty region (AUR) at an end of the each time-slot.

10. The method as recited in claim 9 , wherein the AUR is updated based on feedback which is either an acknowledgement packet (ACK) that identifies that the at least one mobile device has been in the angular coverage region or no packet (NACK) is interpreted as the at least one mobile device not having been in the angular coverage region.

11. A computer system for robust beam tracking and data communication, comprising:

a processor device operatively coupled to a memory device, the processor device being configured to:

divide, by a base station, time into frames each having two phases, a location probing phase and a data communication phase;

determine a steady state analysis of the performance of beam tracking by the base station;

formulate an optimization problem to obtain optimal frame structure maximizing steady state average throughput;

in the location probing phase, use a fractional search policy to localize at least one mobile device by transmitting multiple probing packets over different time-slots and update information about a location of the at least one mobile device; and

in the data communication phase, communicate with the at least one mobile device while expanding a beamwidth to compensate for possible mobility of the at least one mobile device.

12. The system as recited in claim 11 , wherein, when updating the information about the location of the at least one mobile device, the processor device is further configured to:

update the information about the location of the at least one mobile device based on the feedback from the at least one mobile device.

13. The system as recited in claim 11 , wherein the processor device is further configured to:

obtain an optimal data communication duration using quasi-concave programming.

14. The system as recited in claim 11 , wherein an optimal location probing duration of one timeslot is used for location probing.

15. The system as recited in claim 11 , wherein the processor device is further configured to:

estimate a maximum user velocity and a distance between the at least one mobile device and the base station using at least one of global positioning system (GPS) or low frequency channels.

16. The system as recited in claim 11 , wherein the processor device is further configured to:

determine an angular uncertainty region (AUR) on a location of the at least one mobile device; and

match a transmission pattern to the AUR.

17. The system as recited in claim 11 , wherein the processor device is further configured to:

transmit to the at least one mobile device with an average throughput of:

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wherein {circumflex over (R)} is an average throughput in steady state, D is a unit of time for data communication, K is a unit of time for location probing, m is a desgn parameter, and u k is a function of K and D.

18. A computer program product for robust beam tracking and data communication, the computer program product comprising a non-transitory computer readable storage medium having program instructions embodied therewith, the program instructions executable by a computing device to cause the computing device to perform the method comprising:

divide, by a base station, time into frames each having two phases, a location probing phase and a data communication phase;

determine a steady state analysis of the performance of beam tracking by the base station;

formulate an optimization problem to obtain optimal frame structure maximizing steady state average throughput;

in the location probing phase, use a fractional search policy to localize at least one mobile device by transmitting multiple probing packets over different time-slots and update information about a location of the at least one mobile device; and

in the data communication phase, communicate with the at least one mobile device while expanding a beamwidth to compensate for possible mobility of the at least one mobile device.