MODULAR BASE STATION

• US 20130287001A1
• Filed: 01/13/2011
• Published: 10/31/2013
• Est. Priority Date: 01/13/2011
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Sahlin, Henrik, Gransson, Bo
• Granted Patent: US 9,241,333 B2
• Time in Patent Office: Days
• US Class Current: 370/330
• CPC Class Codes: H04B 7/024 Co-operative use of antennas of several sites, e.g. in co-ordinated multipoint or co-operative multiple-input multiple-output [MIMO] systems
• CPC Class Codes: H04B 7/0842 Weighted combining
• CPC Class Codes: H04L 5/0035 Resource allocation in a cooperative multipoint environment
• CPC Class Codes: H04W 72/27 between access points
• CPC Class Codes: H04W 72/52 based on load
• CPC Class Codes: H04W 88/08 Access point devices
• CPC Class Codes: H04W 92/20 between access points

Abstract

A base station module configured to be part of a group of base station modules comprising the base station module and other base station modules, the group of base station modules together forming a base station, and having antennas for receiving radio signals from mobile stations in a base station communication band, a communication interface for transferring data obtained via the received radio signals to the other base station modules and for receiving corresponding data from the other base station module, a data handling unit selects data for transfer to the other base station modules and an uplink data processing unit processes channels used by a subset of the mobile stations communicating with the base station, where the subset is assigned to the base station module. The base station module uses the data received from the other base station modules to influence processing in the uplink data processing unit.

Claims

1. A base station module (50A) configured to be part of a group of base station modules comprising the base station module and other base station modules, the group of base station modules together forming a base station (12), said base station module comprising:

at least one antenna (33A) for receiving radio signals from mobile stations in a base station communication band (CB) comprising a number of channels,

a first communication interface (86A) for transferring data obtained via said received radio signals to the other base station modules (50B, 50C) and for receiving corresponding data obtained via radio signals received by the other base station modules (50B, 50C),

a data handling unit (38A;

110A, 40A;

40A;

46A) configured to select data for transfer to the other base station modules, and

an uplink data processing unit (32A;

48A) configured to process channels used by a subset (S1) of mobile stations (MS1, MS2) of a set of mobile stations communicating with the base station, said subset being assigned to the base station module, where said base station module is configured to use said data received from the other base station modules to influence processing in the uplink data processing unit.

2. The base station module according to claim 1, wherein the data handling unit comprises a demultiplexing element (38A) configured to separate the received radio signals into a first radio signal group of radio signals relating to the assigned subset of mobile stations and a second radio signal group of radio signals not relating to the assigned subset of mobile stations, provide the radio signals in the second radio signal group to the first communication interface (86A) for transfer to the other base station modules (50B, 50C) and provide the radio signals of the first radio signal group to the uplink data processing unit (32A), while the uplink data processing unit (32A) is configured to receive data relating to the assigned mobile stations from the other base station modules (50B, 50C) via the first communication interface (86A) as well as from the demultiplexing element (38A) and process the radio signals of the assigned subset of mobile stations received by all base station modules.

3. The base station module according to claim 1, further comprising an extracting unit (108A) configured to extract data that characterises at least the channels used by the mobile stations of the assigned subset from said radio signals received via said at least one antenna (33A), a weight determining element (110A) being configured to determine weights for the channels used by the mobile stations of the assigned subset based on said data that characterises channels and an antenna combining element (40A) configured to receive said weights from said weight determining element and apply them to the radio signals received via said at least one antenna (33A) for supply of weighted radio signals to the uplink data processing unit (32A;

48A).

4. A base station module according to claim 3, wherein the weights have been selected for contributing to said at least one antenna (33A) forming a beam together with antennas (33B, 33C) of the other base station modules.

5. The base station module according to claim 3 or 4, wherein the data handling unit comprises a symbol probability value handling element (46A) configured to determine symbol probability values for channels used by the whole set of mobile stations based on the received radio signals, send the determined probability values of the channels used by mobile stations in the assigned subset to the uplink data processing unit (48A) and the determined probability values of the channels used by mobile stations in subsets assigned to the other base station modules to the first communication interface (86A) for transfer to the other base station modules (50B, 50C), where the uplink data processing unit (48A) is configured to receive probability values of the channels used by mobile stations in the assigned subset from said other base station modules via the first communication interface (86A) and to process the weighted radio signals using the determined and received symbol probability values.

6. The base station module according to claim 3 or 4, wherein the data handling unit comprises said antenna combining element (40A), which is further configured to provide own weighted radio signals to the first communication interface (86A) for transfer to the other base stations modules, to receive other weighted radio signals from the other base station modules via the first communication interface (86A), to combine the own and other weighted radio signals and supply the combined weighted signals to the uplink data processing unit (32A) for being processed.

7. The base station module according to claim 6, wherein the weight determining element (110A) is further configured to receive data characterising the channels used by the assigned mobile stations being extracted by the other base station modules, to determine weights associated with the channels for the radio signals received by the other base station modules and to transfer these weights to the other base station modules.

8. The base station module according to claim 7, wherein the extracting unit (108A) is further configured to extract from the received radio signals, data characterising the channels used by the mobile stations assigned to the other base station modules and send said data to the other base station modules, while the antenna combining element (40A) is configured to receive weights from the other base station modules via the first communication interface (86A), which received weights are weights determined for channels used by subsets of mobile stations assigned to the other base station modules and to also apply the received weights on radio signals received via said antennas.

9. The base station module according to any previous claim, further comprising a transforming unit (36A) configured to transform the radio signals from the time domain to the frequency domain and the communication interface is provided for communicating frequency domain signals.

10. The base station module according to any previous claim, where there is a preamble detecting unit (174A, 174B) in at least one of the base station modules being configured to detect at least a group of the preambles for all of the base station modules, said base station module further comprising an access channel data extracting unit (172A) configured to extract data received in an access channel and supply to every preamble detecting unit.

11. The base station module according to claim 10, further comprising a preamble detecting unit (174A).

12. The base station module according to any previous claim, further comprising a downlink data processing unit (14A) configured to code data to be sent in radio signals to said assigned subset of mobile stations in corresponding channels and a second communication interface (56A) configured to receive data from the other base station modules concerning the mobile stations in subsets assigned to the other base station modules and transmit data of the mobile stations in the assigned subset to the other base station modules at least one transmitting antenna (53A) via which the data of the whole set of mobile stations is transmitted to the other modules for transmission.

13. The base station module according to claim 12, wherein the data received via the second communication interface are radio signals with data concerning mobile stations outside of the assigned subset and further comprising a multiplexing unit (52A) connected to the downlink data processing unit (14A) and the second communication interface (56A) for receiving coded and modulated signals with data concerning all mobile stations and being configured to combine them to at least one radio signal for transmission over said at least one antenna.

14. The base station module according to claim 12, wherein the downlink data processing module (14A) is connected to the second interface (56A) for sending non-coded and non-modulated data to and receiving non-coded and non-modulated data from the other base station modules and configured to process non-coded and non-modulated data to form said at least one radio signal.

15. The base station module according to any previous claim, where there is a mobile station assigning unit (51) configured to assign mobile stations to the base station modules.

16. The base station module according to claim 15, further comprising a signal quality determining unit (184A) configured to provide the mobile station assigning unit (51) with signal quality data for assisting in the assigning mobile stations.

17. The base station module according to claim 15 or 16, further comprising the mobile station assigning unit.

18. The base station module according to any previous claim, where there is a user data collecting unit (55) connected to the data processing units of all the base station modules for providing a single connection point to other devices of a communication network.

19. The base station module according to claim 17 or 18, wherein the mobile station assigning unit (51) is configured to receive health data from the base station modules and perform mobile station assignment based on the received health data.

20. The base station module according to claim 19, wherein the health data comprises fault location data and the mobile station assigning unit (51) is configured to reconfigure the use of units, elements and/or antennas based on fault location data.

21. The base station module according to any of claims 19-21, wherein the mobile station assigning unit (51) is configured to assign mobile stations based on load, which assigning comprises temporarily disabling a base station module if the load is low.

22. A method for handling communication in a base station module (50A) configured to be part of a group of base station modules comprising the base station module and other base station modules, the group of base station modules together forming a base station (12), the method being performed in the base station module and comprising:

receiving (88;

96;

114;

136;

154) radio signals from mobile stations in a base station communication band (CB) comprising a number of channels,

transferring (90;

102;

124;

128;

146;

166) data obtained via said received radio signals to the other base station modules (50B, 50C),

receiving (92;

104;

122;

130;

148;

168) corresponding data obtained via radio signals received by the other base station modules,

processing (94;

106;

134;

152) data in channels used by a subset (S1) of mobile stations (MS1, MS2) communicating with the base station, the subset (S1) being assigned to the base station module, and

using (95) said data received from the other base station modules to influence the processing.

23. The method according to claim 22, further comprising separating (100) said received radio signals into a first radio signal group of radio signals relating to the assigned subset of mobile stations and a second radio signal group of radio signals not relating to the assigned subset of mobile stations, where the transferring comprises transferring (102) the second radio signal group of radio signals to the other base station modules, the receiving of corresponding data comprises receiving (104) radio signals from mobile stations of the assigned subset having been separated by the other base station modules (50B, 50C) and the processing comprises processing (106) the radio signals in the first radio signal group and from the mobile stations of the assigned subset received by the other base station modules.

24. The method according to claim 22, further comprising extracting (118;

140;

158) data characterising the channels used by the assigned mobile stations from the received radio signals, determining (121;

142;

160) weights for the channels used by the mobile stations in the assigned subset based on said data that characterises channels and weighting (126;

144;

162) the received radio signals with weights comprising said determined weights.

25. The method according to claim 24, further comprising determining (164) symbol probability values for the channels used by the whole set of mobile stations based on the received radio signals, where the transferring of data comprises transferring (166) symbol probability values of channels used by mobile stations in subsets assigned to the other base station modules (50B, 50C), receiving data from the other base station modules comprises receiving (168) symbol probability values of channels used by mobile stations in the assigned subset and processing comprises processing the weighted radio signals using determined and received symbol probability values.

26. The method according to claim 24, wherein transferring data comprises transferring (128;

146) own weighted received radio signals to the other base station modules (50B, 50C) and receiving data comprises receiving (130;

148) other weighted radio signals received by the other base station modules, the method further comprising combining (132;

150) the own and other weighted radio signals and processing being performed on the combined radio signals.

27. The method according to claim 26, further comprising receiving (120) data characterising the channels used by the assigned mobile stations being extracted by the other base station modules (50B, 50C), where the determining (121) of weights comprises determining of weights associated with the channels for the radio signals received by the other base station modules and further comprising transferring (122) these weights to the other base station modules.

28. The method according to claim 27, wherein the extracting (118) comprises extracting, from the received radio signals, data characterising the channels used by the mobile stations assigned to the other base station modules, sending (119) said data to the other base station modules, receiving (124) weights from the other base station modules, which received weights are weights determined for channels used by subsets of mobile stations assigned to the other base station modules, and applying the own and received weights when weighting (126) the received radio signals.

29. The method according to any of claims 22-28, further comprising transforming (98;

116;

138;

156) the received radio signals from the time domain to the frequency domain, where the transferring and receiving to and from the other base station modules is performed on data in the frequency domain.

30. The method according to any of claims 22-29, further comprising coding (64;

80) data to be sent in radio signals to said assigned set of mobile stations in corresponding channels, receiving (68;

76) data from the other radio base station modules concerning the rest of the mobile stations and transmitting (66;

74) data concerning said assigned set of mobile stations to the other base station modules.

31. The method according to claim 30, wherein the data received via the second communication interface are radio signals with data concerning mobile stations outside of the assigned set and further comprising combining (70) coded and modulated signals with data concerning all mobile stations and to at least one radio signal and transmitting (72) the signal over said at least one antenna.

32. The method according to claim 30, further comprising sending (74) non-coded and non-modulated data to and receiving (76) non-coded and non-modulated data from the other base station modules and processing (80) non-coded and non-modulated data to form said at least one radio signal.

33. The method according to any of claims 22-32, further comprising assigning (192) mobile stations to the base station modules.

34. The method according to claim 33, wherein assigning is performed based on signal quality data.

35. The method according to claim 33 or 34, further comprising receiving (188) health data from the base station modules and mobile station assignment is performed based on the received health data.

36. The method according to claim 35, wherein the health data comprises fault location data and assigning comprises reconfiguring the use of units, elements and/or antennas based on fault location data.

37. The method according to any of claims 31-34, wherein the assigning of mobile stations is performed based on load, which comprises temporarily disabling a base station module if the load is low.