RADIO ACCESS NETWORKS

• US 20160037550A1
• Filed: 06/09/2015
• Published: 02/04/2016
• Est. Priority Date: 06/09/2014
• Status: Active Grant

• Current Assignee: CommScope Technologies, LLC (CommScope Holding Company, Inc.)
• Original Assignee: Airvana LP (CommScope Holding Company, Inc.)
• Inventors: Barabell, Arthur J., Eyuboglu, Vedat, Mahalingam, Nagi Jayaraman, Raghothaman, Balaji, Sandberg, Stuart, Ahmadi, Sassan
• Granted Patent: US 10,057,916 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04B 17/318 Received signal strength
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/046 the resource being in the space domain, e.g. beams
• CPC Class Codes: H04W 72/1263 Mapping of traffic onto schedule, e.g. scheduled allocation or multiplexing of flows
• CPC Class Codes: H04W 84/047 using dedicated repeater stations
• CPC Class Codes: H04W 88/085 Access point devices with remote components

Abstract

An example communication system in a cellular network comprises: a processing system comprising a controller and remote units, with the remote units being configured to communicate with the controller and to communicate with mobile devices within a communication cell of the cellular network. At least part of the processing system is configured to perform operations comprising: estimating signal strength experienced by all or some of the mobile devices; identifying, based at least on the signal strength, one or more of the mobile devices that can be scheduled for communication with one or more of the remote units in the communication cell on a same airlink resource; and scheduling the communication.

Claims

1. A communication system in a cellular network, comprising:

a processing system comprising a controller and remote units, the remote units being configured to communicate with the controller and to communicate with mobile devices within a communication cell of the cellular network;

wherein at least part of the processing system is configured to perform operations comprising;

estimating signal strength experienced by all or some of the mobile devices;

identifying, based at least on the signal strength, one or more of the mobile devices that can be scheduled for communication with one or more of the remote units in the communication cell on a same airlink resource; and

scheduling the communication between the one or more mobile devices and the one or more remote units.

2. The communication system of claim 1, wherein:

the airlink resource comprises a frequency band;

at least some communication among at least some of the controller, the remote units, and the mobile devices occurs using radio frequency (RF) signals, at least some of the RF signals representing information destined for, or originating from, a mobile device;

the remote units are configured to communicate with the mobile devices using RF signals;

the controller is configured to estimate the signal strength experienced by a mobile device, and to represent the estimate numerically, the estimate corresponding to transmission or reception needs of the mobile device for which the estimate was made; and

the controller comprises a real-time scheduler configured to perform the scheduling for the mobile device based on the estimate.

3. The communication system of claim 2, wherein the transmission or reception needs of the mobile device correspond to estimated signal loss between the mobile device and one or more of the remote units.

4. The communication system of claim 3, wherein the estimated signal loss is based on an uplink transmission from the mobile device to one or more of the remote units.

5. The communication system of claim 4, wherein the uplink transmission is based on an LTE Sounding Reference Signal (SRS) transmission.

6. The communication system of claim 4, wherein the uplink transmission is based on an LTE PRACH transmission.

7. The communication system of claim 4, wherein the uplink transmission is based on an LTE PUCCH transmission.

8. The communication system of claim 4, wherein the uplink transmission is based on an LTE PUSCH transmission.

9. The communication system of claim 2, wherein the transmission or reception needs of the mobile device is based on traffic load experienced by one or more of the remote units.

10. The communication system of claim 2, wherein the estimate is represented using numerical values that are based on one or more measurements on an uplink from a mobile device to a remote unit.

11. The communication system of claim 2, wherein the estimate is represented using numerical values that are 0 or 1.

12. The communication system of claim 2, wherein the estimate is represented using numerical values that are values selected from a finite number of levels greater than two.

13. The communication system of claim 1, wherein an estimate of signal strength for a mobile device is represented using numerical values;

wherein, for the mobile device, the numerical values form a quantized signature vector; and

wherein the controller is configured to perform operations comprising;

determining, based on quantized signature vectors for the mobile device and at least one other mobile device that the mobile device and the at least one other mobile device can be scheduled on the same airlink resource for communication.

14. The communication system of claim 1, wherein an estimate of signal strength for a mobile device is represented using numerical values;

wherein, for the mobile device, the numerical values form a quantized signature vector; and

wherein the quantized signature vector is based on a threshold signal-to-interference-plus noise ratio (SINR)

15. The communication cell of claim 1, wherein an estimate of signal strength for a mobile device is represented using numerical values;

wherein, for the mobile device, the numerical values form a quantized signature vector; and

wherein two mobile devices can be scheduled on a same frequency band in response to a sum of quantized signature vectors for the two mobile devices having no component that exceeds a preset threshold.

16. The communication system of claim 1, wherein an estimate of signal strength for a mobile device is represented using numerical values;

and

wherein the numerical values are based, at least in part, on a location of the mobile device within the communication cell.

17. The communication system of claim 1, wherein at least two of the remote units are configured so that, when two or more mobile devices are scheduled for communication on a same airlink resource, different ones of the remote units communicate with different mobile devices on the same airlink resource.

18. The communication system of claim 1, wherein at least one of the remote unit is configured so that, when two or more mobile devices are scheduled for communication on a same airlink resource, the at least one of the remote units does not communicate with any mobile device.

19. The communication system of claim 1, wherein at least one of the remote units is configured so that, when two or more mobile devices are scheduled for communication on a same airlink resource, the at least one of the remote units is capable of communicating with multiple mobile devices at simultaneously.

20. The communication link of claim 19, wherein the at least one remote unit is configured to communicate using a reduced transmit power.

21. The communication system of claim 1, wherein the controller is configured to cause communication with a mobile device to occur at a transmission power that is below a standard transmission power in a case where the mobile device is within a specified distance of a remote unit.

22. The communication system of claim 21, wherein the controller is configured to determine if the mobile device is within the specified distance based on one or more measurements of uplink transmissions of the mobile device at one or more remote units.

23. The communication system of claim 22, wherein the uplink transmissions comprise one or more of:

LTE SRS, PUCCH, PRACH or PUSCH transmissions.

24. The communication system of claim 1, wherein the operations comprise determining a bit rate at which data is to be transmitted to and from a mobile device.

25. The communication system of claim 1, wherein the operations comprise determining a bit rate for communication between a mobile device and a remote unit, and wherein determining the bit rate comprises:

receiving, from the remote unit, information about one or more measurements on an uplink control channel between the mobile device and the remote units; and

using the one or more measurements to determine the bit rate.

26. The communication system of claim 24, wherein the bit rate is based on uncertainty due to small-scale fading.

27. The communication system of claim 1, wherein the operations comprise determining a bit rate for communication between a mobile device and a remote unit, and wherein determining the bit rate comprises:

receiving, from the mobile device, feedback information about success or failure of past data transmissions; and

using the feedback information to determine the bit rate.

28. The communication system of claim 27, wherein the feedback information comprises Hybrid ARQ (HARQ) feedback.

29. The communication system of claim 28, wherein, in a case that a dominant interferer of the mobile device has changed, past HARQ feedback is not used when determining the bit rate.

30. The communication system of claim 1, wherein the operations comprise determining a bit rate for communication between a mobile device and a remote unit, and wherein determining the bit rate comprises:

receiving, from mobile devices, channel state information (CSI) feedback; and

using the CSI feedback to determine the bit rate.

31. The communication system of claim 1, wherein the operations comprise determining a bit rate for communication between a mobile device and a remote unit, and wherein determining the bit rate comprises:

receiving, from mobile devices, channel state feedback including an interference measurement; and

using channel state feedback including the interference measurement to determine the bit rate.

32. The communication system of claim 31, wherein the interference measurement is based on an LTE Channel State Information Reference Signal (CSI-RS).

33. The communication system of claim 31, wherein the interference measurement is reported by a mobile device that is configured to report interference measurements for different interference scenarios.

34. The communication system of claim 1, wherein a same airlink resource is for downlink transmission from one or more remote units to a mobile device.

35. The communication system of claim 1, wherein a same airlink resource is for uplink transmission from a mobile device to one or more remote units.

36. The communication system of claim 1, wherein a same airlink resource is for uplink transmission from a mobile device and one or more other mobile devices to one or more remote units for which signals are jointly processed.

37. The communication system of claim 1, wherein an estimate of signal strength is represented using numerical values;

wherein, for a mobile device, the numerical values form a quantized signature vector; and

wherein the controller is configured to perform operations comprising;

determining that the quantized signature vector is orthogonal to another quantized signature vector by performing a logical operation using the quantized signature vector and the other quantized signature vector

38. The communication system of claim 1, wherein the operations comprise:

determining which remote units are to communicate which mobile devices based, at least in part, on locations of mobile devices within the communication cell.

39. The method of claim 1, wherein the operations comprise:

dividing the communication cell into virtual cells such that different mobile devices in at least two different virtual cells are configured for communication on the same frequency; and

for a mobile device at a border of first and second virtual cells, controlling a first remote unit in the first virtual cell to transmit to the mobile device at a non-maximum power level and controlling a second remote unit in the second virtual cell to transmit to the mobile device at a non-maximum power level.

40. The communication system of claim 1, wherein the operations comprise determining bit rates at which communications are to be transmitted between the two or more mobile devices and the two or more remote units.

41. The communication system of claim 40, wherein determining a bit rate for communication between a mobile device and a remote unit comprises:

receiving, from all remote units in the communication cell, information on an uplink control channel, the information corresponding to a predicted signal strength for the mobile device in the communication cell, the predicted strength deviating from an actual signal strength for the mobile device in the communication cell, the predicted signal strength being associated with a first bit rate; and

reducing the first bit rate based on the actual signal strength to produce a second bit rate for communication between a mobile device and a remote unit.

42. The communication system of claim 1, wherein the remote units are configured to perform at least some baseband processing, the at least some baseband processing including receiving and extracting the information on an uplink control channel;

and

wherein the operations further comprise load-balancing communications to remote units on the uplink control channel, where load-balancing comprises setting periods and phases for transmissions from some mobile devices so as not to overlap with transmissions of other mobile devices.

43. The communication system of claim 1, wherein the operations further comprise load-balancing communications to remote units on an uplink control channel, where load-balancing comprises setting periods for transmissions from some mobile devices based on a communication traffic load in the communication cell.

44. The communication system of claim 1, wherein the communication scheduled is on a downlink from the two or more remote units to two or more mobile devices.

45. The communication system of claim 1, wherein the communication scheduled is on an uplink from the two or more remote units to two or more mobile devices.

46. The communication system of claim 1, wherein the mobile devices comprise a first mobile device and a second mobile device;

and

wherein identifying comprises identifying that the first and second mobile devices can be scheduled for communication on a same frequency on an uplink.

47. The communication system of claim 46, wherein the uplink comprises at least one of LTE PUCCH or PUSCH channels.

48. The communication system of claim 1, wherein the operations comprise dividing the communication cell into virtual cells such that different mobile devices in at least two different virtual cells are configured to communicate on a same frequency;

and

wherein the same frequency comprises a part of a larger frequency band, the different mobile devices being configured also to communicate over different frequencies within the larger frequency band.

49. The communication system of claim 1, wherein the controller comprises a first controller and the processing system comprises one or more second controllers, the first controller coordinating operation of the one or more second controllers, each of the remote units being configured to communicate with a corresponding second controller and to communicate wirelessly with mobile devices.

50. The communication system of claim 49, wherein the first controller implements a central coordination function to control operations of the one or more second controllers.

51. The communication system of claim 1, wherein the operations comprise:

determining locations of the mobile devices within the communication cell; and

scheduling communication between two or more mobile devices and two or more remote units so as to selectively allocate resources in the two or more remote units.

52. The communication system of claim 1, wherein the operations further comprise load management of an uplink control channel processing load on the remote units, where load management comprises adjusting periods for transmissions from some mobile devices based on a communication traffic load in the communication cell.

53. The communication system of claim 52, wherein the communication traffic load is based on the number of connected users.

54-72. -72. (canceled)

73. In a communication system in a cellular network, where the communication system comprises a processing system comprising a controller and remote units, where the remote units are configured to communicate with the controller and to communicate with mobile devices within a communication cell of the cellular network, one or more non-transitory machine-readable storage media storing instructions that are executable by the processing system to perform operations comprising:

estimating signal strength experienced by all or some of the mobile devices;

identifying, based at least on the signal strength, one or more of the mobile devices that can be scheduled for communication with one or more of the remote units in the communication cell on a same airlink resource; and

scheduling the communication between the one or more mobile devices and the one or more remote units.

74-128. -128. (canceled)