Wireless base station device and path search method

• US 20060068790A1
• Filed: 02/25/2005
• Published: 03/30/2006
• Est. Priority Date: 09/30/2004
• Status: Abandoned Application

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Sawamoto, Toshiro, Minowa, Morihiko
• Application Number:
  US11/064,855
• Publication Number:
  US 20060068790A1
• Time in Patent Office: Days
• US Class Current: 455/441
• CPC Class Codes: H04B 1/7113 Determination of path profile
• CPC Class Codes: H04B 1/7117 Selection, re-selection, allocation or re-allocation of paths to fingers, e.g. timing offset control of allocated fingers
• CPC Class Codes: H04W 36/0083 Determination of parameters used for hand-off, e.g. generation or modification of neighbour cell lists
• CPC Class Codes: H04W 36/083 wherein at least one of the access points is a moving node
• CPC Class Codes: H04W 36/324 by mobility data, e.g. speed data
• CPC Class Codes: H04W 56/00 Synchronisation arrangements
• CPC Class Codes: H04W 56/0005 synchronizing of arrival of multiple uplinks

Abstract

In a wireless base station device that communicates with a mobile device via an advance base station, the reception timing determination portion determines the reception timing of data that is transmitted by a mobile device that exists in a cell of the advance base station on the basis of the distance between the wireless base station device and the advance base station and the cell radius of the advance base station. The data reception portion receives data from the mobile device by performing a reception operation at the reception timing, the delay profile creation portion creates delay profiles on the basis of the received data, and the path detection portion detects paths from the mobile device on the basis of the delay profiles.

Claims

1. A wireless base station device that communicates with a mobile device via an advance base station, comprising:

a reception timing determination portion that determines reception timing of data that is transmitted by a mobile device that exists in a cell of the advance base station on the basis of the distance between the wireless base station device and the advance base station and the cell radius of the advance base station;

a data reception portion that receives data from the mobile device by performing a reception operation at the reception timing;

a delay profile creation portion that creates a delay profile on the basis of the received data;

a path detection portion that detects paths from the mobile device on the basis of the delay profile; and

a demodulation portion that demodulates data from signals received via the detected paths.

2. The wireless base station device according to claim 1, comprising:

means for measuring the distance between the wireless base station device and the advance base station; and

a memory for storing the radius of the cell of each advance base station and the reception timing of a channel that is allocated to the mobile device that exists in each cell,

wherein the reception timing determination portion determines the reception start timing and reception end timing for each channel on the basis of the distance, cell radius, and channel reception timing.

3. The wireless base station device according to claim 1, wherein the advance base station includes an advance base station that is cascade-connected to the advance base station.

4. The wireless base station device according to claim 1, comprising:

a handover control portion that controls handover that is implemented in accordance with movement of the mobile device,

wherein the reception timing determination portion determines, on the basis of control by the handover control portion, the reception timing of data transmitted by the mobile device via each of the cells associated with the handover;

the delay profile creation portion creates delay profiles on the basis of data received from each cell at said respective reception timings; and

the path detection portion detects paths of large power from all of said delay profiles.

5. The wireless base station device according to claim 4, wherein the handover control portion references the respective reception timings and calculates the difference between the timing at which the delay profile was generated first and the timing at which another delay profile was generated and, when the difference is equal to or more than a set value, implements control to shorten the total processing time for delay profile creation and path detection.

6. The wireless base station device according to claim 5, wherein the handover control portion reduces the number of oversamples of received data such that the delay profile creation time is shortened.

7. The wireless base statiori device according to claim 5,

wherein a memory for storing interference power is provided for each cell;

and

the handover control portion shortens the processing time for path detection by using the interference power stored in the memory instead of calculating an average interference power.

8. The wireless base station device according to claim 4, wherein the handover control portion manages the channels of all the cells of the mobile device undergoing handover and detects the paths from the mobile device for which the delay profiles of all the channels have been gathered.

9. A path search circuit of a wireless base station device that communicates with a mobile device via an advance base station, detects paths from the mobile device to the advance base station, and demodulates data from signals received via the paths, comprising:

a reception timing determination portion that determines reception timing of data that is transmitted by a mobile device that exists in a cell of the advance base station on the basis of the distance between the wireless base station device and the advance base station and the cell radius of the advance base station;

a data reception portion that receives data from the mobile device by performing a reception operation at the reception timing;

a delay profile creation portion that creates a delay profile on the basis of the received data; and

a path detection portion that detects paths from the mobile device on the basis of the delay profile.

10. The path search circuit according to claim 9, comprising:

means for measuring the distance between the wireless base station device and the advance base station; and

a memory for storing the radius of the cell of each advance base station and the reception timing of a channel that is allocated to the mobile device that exists in each cell,

wherein the reception timing determination portion determines the reception start timing and reception end timing for each channel on the basis of the distance, cell radius, and channel reception timing.

11. The path search circuit according to claim 9, comprising:

a handover control portion that controls handover that is implemented in accordance with movement of the mobile device,

wherein the reception timing determination portion determines, on the basis of control by the handover control portion, the reception timing of data transmitted by the mobile device via each of the cells associated with the handover;

the delay profile creation portion creates delay profiles on the basis of data received from each cell at said respective reception timings; and

the path detection portion detects paths of large power from all of said delay profiles.

12. The path search circuit according to claim 11, wherein the handover control portion references the respective reception timings and calculates the difference between the timing at which the delay profile was generated first and the timing when another delay profile was generated and, when the difference is equal to or more than a set value, implements control to shorten the total processing time for delay profile creation and path detection.

13. The path search circuit according to claim 11, wherein the handover control portion manages the channels of all the cells of the mobile device undergoing handover and detects the paths from the mobile device for which the delay profiles of all the channels have been gathered.

14. A path search method of a wireless base station device that communicates with a mobile device via an advance base station, detects paths from the mobile device to the advance base station, and demodulates data from signals received via the paths, comprising the steps of:

determining the reception timing of data that is transmitted by a mobile device that exists in a cell of the advance base station on the basis of the distance between the wireless base station device and the advance base station and the cell radius of the advance base station;

receiving data from the mobile device by performing a reception operation at the reception timing; and

creating a delay profile on the basis of the received data;

detecting paths from the mobile device on the basis of the delay profile.

15. The path search method according to claim 14, comprising the steps of:

pre-storing the cell radius of each of the advance base stations and the reception timings of channels allocated to mobile devices that exist in each cell to memory;

measuring the distance between the wireless base station device and the advance base stations; and

determining a data reception start timing and a data reception end timing for each channel on the basis of the distance, the cell radius, and the channel reception timings.

16. The path search method according to claim 14 er 15, comprising the steps of:

determining, during a handover that is implemented in accordance with movement of a mobile device, the reception timings of data transmitted by the mobile device via each of the cells that are associated with the handover;

performing a reception operation from each of the cells at the reception timings;

creating a delay profile on the basis of each of the received data; and

detecting paths of large power from all of said delay profiles.

17. The path search method according to claim 16, comprising the steps of:

computing the difference between the timing at which the delay profile was created first and the timing at which another delay profile was created by referencing the respective reception timings; and

,

when the difference is equal to or more than a set value, implementing control to shorten the total processing time of delay profile creation and path detection.

18. The path search method according to claim 17, comprising the step of:

shortening the delay profile creation time by reducing the number of oversamples of received data.

19. The path search method according to claim 17, comprising the step of:

providing a memory for storing interference power for each of the advance base stations; and

shortening the processing time for path detection by using the interference power that is stored in the memory instead of calculating an average interference power.

20. The path search method according to claim 16, comprising the step of:

managing the channels of all the cells of the mobile device undergoing handover and detecting the paths from the mobile device for which the delay profiles of all the channels have all been gathered.