Anti-synchronous radio channel slicing for smoother handover and continuous service reception

• US 20040057400A1
• Filed: 09/24/2002
• Published: 03/25/2004
• Est. Priority Date: 09/24/2002
• Status: Abandoned Application

• Current Assignee: Nokia Corporation
• Original Assignee: Nokia Corporation
• Inventors: Walsh, Rod, Hakulinen, Harri
• Application Number:
  US10/252,549
• Publication Number:
  US 20040057400A1
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04L 1/06 using space diversity
• CPC Class Codes: H04L 1/08 by repeating transmission, e.g. Verdan system H04L1/1858 and H04L1/189 take precedence
• CPC Class Codes: H04L 1/18 Automatic repetition systems, e.g. Van Duuren systems
• CPC Class Codes: H04L 2001/0096 Channel splitting in point-to-point links

Abstract

Aspects of the invention enable mobile wireless terminals to perform fast handover without packet loss, network buffering and uplink signaling in cellular communication systems. Further aspects of the invention prevent the loss of data that is often associated with communication errors introduced into wireless data communication transmissions, particularly errors associated with the handover of cellular communications. The invention may include the use of a time slicing and scheduling technique for redundantly transmitting data over multiple channels. In accordance with this aspect of the invention, each redundant copy of a respective group of data may be sent over a different channel at different times, thereby enabling the portable device to acquire lost data or to replace data containing an unacceptable amount of error. The invention may implement resource scheduling for managing the transmission of the data groups at the appropriate times to increase the likelihood that a data group will be received over at least one channel without interruption. In addition, the portable device may be provided with information describing the transmission schedule for tuning, at the appropriate time, to the transmitter of the cell on which the data is being retransmitted. The system may also be implemented to control the transmission of data over alternative multi access systems.

Claims

1. A system for transmitting data to a portable device over a wireless network, comprising:

a first resource slicer transmitting data to the portable device in accordance with a first pattern of transmitting data at selected times;

a second resource slicer transmitting the same data to the portable device in accordance with a second pattern of transmitting data at selected times; and

a slicing area manager, wherein the slicing area manager schedules the transmission of data from the first and second resource slicers such that different data is transmitted for each selected time.

2. The system according to claim 1 wherein the wireless network is a cellular network.

3. The system according to claim 1 wherein the wireless network is a packet based network.

4. The system according to claim 1 wherein the wireless network is a mobile Internet network.

5. The system according to claim 1 wherein the wireless network is a broadcast network.

6. The system according to claim 1 wherein the data is formed into groups for transmission.

7. The system according to claim 6 wherein the groups of data are formed from grouping together service groups.

8. The system according to claim 1 wherein the resource slicers buffer data for transmission to the portable device.

9. The system according to claim 1 wherein the system includes one or more processors that calculate the transmission schedule for transmitting data to the portable device over multiple channels, wherein each channel is assigned to a coverage area within the wireless network.

10. The system according to claim 9 wherein the one or more processors schedule the transmission of at least some of the same data to the portable device over different network resources at non-overlapping times.

11. The system according to claim 9 wherein the one or more processors schedule the start of the transmission of data to the portable device over different network resources at different times.

12. The system according to claim 9 wherein the transmissions use network resources corresponding to channels within the wireless network, and the one or more processors schedule the transmission of data to the portable device over each of the channels at partially overlapping times.

13. The system according to claim 9 wherein the transmissions use network resources corresponding to codes in a code division multiple access transmission scheme and the slicing area manager schedules the transmission of data to the portable device using different codes of a code division multiple-access network.

14. The system according to claim 9 wherein the transmissions use network resources corresponding to codes in a code division multiple access transmission scheme and the slicing area manager schedules the transmission of the same data to the portable device using the same code at non-overlapping times.

15. The system according to claim 9 wherein the one or more processors schedule the transmission over a single communication link of different data to the portable device using different codes at different times.

16. The system according to claim 9 wherein the one or more processors schedule the transmission of data to the portable device using different frequencies of a frequency division multiple-access network.

17. The system according to claim 16 wherein the one or more processors schedule the transmission of data to the portable device over each of the different frequencies at non-overlapping times.

18. The system according to claim 1 further including a plurality of slicing area managers and at least one network slicing manager coupled to the slicing area managers for coordinating the management of data transmissions.

19. The system according to claim 9 wherein if the portable device fails to properly receive data transmitted over a first channel, the portable device receives data transmitted over a second channel based on a schedule for transmitting the data.

20. The system according to claim 19 wherein the channels comprise areas relating to one or more cells.

21. The system according to claim 9 wherein the first resource slicer transmits a notification to the portable device indicating a schedule for transmitting data in a second area by the second resource slicer which is used if the portable devices fails to properly receive data transmitted in a first area.

22. The system according to claim 1 wherein the first resource slicer and the second resource slicer each form part of separate devices within the network.

23. The system according to claim 1 wherein the first resource slicer, the second resource slicer, and the slicing area manager each form part of separate devices within the network.

24. A system for communicating data to a portable device over a wireless network, comprising:

a resource slicer that organizes data, intended for transmission to the portable device over a plurality of transmitters, for transmission in multiple coverage areas at selected times; and

a slicing area manager that schedules the transmission of the data over each of the plurality of transmitters and further scheduling the transmission of the data at different times in each of the respective coverage areas.

25. The system according to claim 24, wherein the slicing area manager schedules the transmission of the same data at different times over different channels within the wireless network.

26. The system according to claim 24, wherein the slicing area manager schedules the transmission of the same data at different times using different spreading codes.

27. The system according to claim 24, wherein the slicing area manager schedules the transmission of the same data at different times using different frequencies.

28. The system according to claim 24 wherein the data is formed into groups for transmission.

29. The system according to claim 28 wherein the groups of data are formed from grouping together service groups.

30. A portable device for performing wireless communications over a wireless network, the device including,

a communications unit that receives groups of data at selected times over the wireless network;

a processor that detects an unsuccessful communication of a group of data; and

a transmission selection unit that selects an alternative communication resource from which the communications unit can receive the unsuccessfully communicated group of data in accordance with schedule information indicating the alternative resource at which the unsuccessfully communicated group of data will be transmitted.

31. The portable device according to claim 30, wherein the processor detects an unsuccessful communication based on a detected rate of error contained in the received data.

32. The portable device according to claim 30, wherein the processor detects an unsuccessful communication based on the loss of a connection with the network.

33. The portable device according to claim 30, wherein the communications unit receives the schedule information from a network device.

34. The portable device according to claim 30, wherein the schedule information is determined based on a predictive transmission algorithm for learning the time at which the data unsuccessfully communicated will be retransmitted.

35. The portable device of claim 30, wherein:

the processor instructs the communications unit to connect to a neighboring cell before the portable device exits the area corresponding to the cell in which the portable device is located.

36. The portable device of claim 30, wherein:

the processor instructs the communications unit to connect to one or more neighboring cells while connected to the cell in which the portable device is located.

37. The portable device of claim 30, wherein:

the processor instructs the communications unit to connect to a neighboring cell while connected to the cell in which the portable device is located;

the processor further detects error in at least one group of data received over one of the channels to which the portable device is connected; and

the processor controls the portable device to extract data from another channel to which the portable device is connected.

38. A method of communicating over a wireless network with a portable communication device, comprising:

receiving data to be transmitted to the portable device;

organizing the received data into segments for transmission; and

scheduling the transmission of each of the segments of data over each of a plurality of channels at different times.

39. The method according to claim 38, wherein each channel over which the segments of data are to be transmitted corresponds to a cell of a cellular network, and the method further comprising selecting channels for transmission of the segments of data corresponding to cells neighboring the cell in which the portable device is located.

40. The method according to claim 39, further comprising transmitting the segments of data over the channel corresponding to the cell in which the portable device is located.

41. The method according to claim 39, further comprising developing a schedule for the transmission of each segment of data over each channel corresponding to neighboring cells at non-overlapping times.

42. The method according to claim 38, further comprising inserting a delay between the transmission of each segment of data.

43. The method according to claim 38, wherein organizing the received data into segments for transmission further comprises grouping the incoming data into groups that benefit from being delivered together in a single segment.

44. The method according to claim 38, wherein scheduling the transmission of each of the segments of data over each of a plurality of channels at different times includes initiating the transmission of each of the segments of data over a plurality of channels at different times.

45. A method of communicating data over a wireless network with a portable communication device, comprising:

splitting data into at least a first group of data (G1) and a second group of data (G2) for transmission of the first (G1) and second (G2) groups of data in at least two adjacent cell areas; and

scheduling the transmission of the first group of data (G1) in at least a first adjacent cell area (A1) and a second adjacent cell area (A2) such that completion of the transmission of the first group of data (G1) in the first adjacent cell area (A1) occurs at a time spaced apart from the start of transmission of the first group of data (G1) in the second adjacent cell area (A2).

46. The method according to claim 45, wherein initiation of the transmission of at least the first group of data (G1) and the second group of data (G2) in at least the first adjacent cell area (A1) and the second adjacent cell area (A2) occur at different times.

47. The method according to claim 45, wherein upon completion of the transmission of the first group of data (G1) in the first adjacent cell area (A1), transmitting a second group of data (G2) in the first adjacent cell area (A1).

48. The method according to claim 45, wherein the time spacing between the completion of the transmission of the first group of data (G1) in the first adjacent cell area (A1) and the start of transmission of the first group of data (G1) in the second adjacent cell area (A2) is dependent on the number of adjacent cell areas over which the data is to be transmitted.

49. The method according to claim 45, wherein the time spacing between the completion of the transmission of the first group of data (G1) in the first adjacent cell area (A1) and the start of transmission of the first group of data (G1) in the second adjacent cell area (A2) is dependent on the number of groups of data to be transmitted over the adjacent cell areas and the number of adjacent cell areas over which the data is to be transmitted.

50. The method according to claim 45, wherein if the number of adjacent cell areas over which data is to be transmitted are fewer than the number of groups to be transmitted, the time spacing between the completion of the transmission of the first group of data (G1) in the first adjacent cell area (A1) and the start of transmission of the first group of data (G1) in the second adjacent cell area is (A2) shorter than the time for transmitting the first group of data (G1).

51. The system according to claim 45 wherein the groups of data are formed from grouping together service groups.

52. A method of communicating with a portable communication device over a wireless network, comprising the steps of:

organizing data to be transmitted to the portable device into segments for transmission to the portable device;

scheduling the transmission of each segment of data such that transmission of each segment of data over each of a plurality of areas of the network is initiated at different times;

establishing a connection between the portable device and the transmitter of one or more neighboring areas; and

transmitting each data segment over the plurality of areas of the network at different times.