Wireless base station and wireless terminal

• US 20070230396A1
• Filed: 08/14/2006
• Published: 10/04/2007
• Est. Priority Date: 03/31/2006
• Status: Abandoned Application

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Watanabe, Masahiro
• Application Number:
  US11/503,755
• Publication Number:
  US 20070230396A1
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04L 2027/0065 Frequency error detectors H04L2027/0067 takes precedence
• CPC Class Codes: H04L 25/0212 of impulse response

Abstract

A wireless base station receiving packet signals at every timeslot from a plurality of wireless terminals, has a calculating unit calculating, from one packet signal, a parameter used for a process of demodulating the packet signal, a storage unit stored with the parameter, and an averaging processing unit calculating, when executing the demodulating process of the packet signal at a certain timeslot with respect to one of the plurality of wireless terminals, an average value from the parameter obtained from the packet signal and from the parameters stored in the storage unit and obtained from the packet signals at one or more timeslots allocated to one of the plurality of wireless terminals and discontinuous from the certain timeslot, and outputting the average value as the parameter used for the demodulating process.

Claims

1. A wireless base station receiving packet signals at every timeslot from a plurality of wireless terminals, comprising:

a calculating unit calculating, from one packet signal, a parameter used for a process of demodulating the packet signal;

a storage unit stored with the parameter; and

an averaging processing unit calculating, when executing the demodulating process of the packet signal at a certain timeslot with respect to one of the plurality of wireless terminals, an average value of the parameters from the parameter obtained from the packet signal of the certain timeslot and from the parameters stored in the storage unit and obtained from the packet signals at one or more timeslots allocated to the one of the plurality of wireless terminals and discontinuous from the certain timeslot, and outputting the average value as the parameter used for the demodulating process.

2. A wireless base station according to claim 1, further comprising a determining unit determining the plurality of parameters used for calculating the average value in the averaging processing unit on the basis of slot allocation information representing a relationship between the plurality of timeslots and the wireless terminals allocated to the respective timeslots.

3. A wireless base station according to claim 1, wherein the one or more timeslots discontinuous from the certain timeslot are positioned within a predetermined time range centering at the certain timeslot.

4. A wireless base station according to claim 1, further comprising a weighting unit weighting, by the standard of the parameter corresponding to the certain timeslot, the plurality of parameters for calculating the average value.

5. A wireless base station according to claim 4, wherein the weighting unit applies a heaviest weight to the parameter corresponding to the certain timeslot, and applies a weight getting smaller as a time interval from the certain timeslot becomes larger to the parameter corresponding to the one or more timeslots.

6. A wireless base station according to claim 1, wherein the parameter is a channel estimation value of a packet signal.

7. A wireless base station according to claim 1, wherein the parameter is a frequency offset estimation value between the wireless base station and the wireless terminal.

8. A wireless-base station according to claim 1, wherein the parameter is an arrival direction estimation value of the packet signal.

9. A wireless terminal performing communications with a wireless base station transmitting packet signals to a plurality of wireless terminals at every timeslot, comprising:

a calculating unit calculating, from one packet signal received from the wireless base station and transmitted to a target terminal, a parameter used for a process of demodulating the packet signal;

a storage unit stored with the parameter; and

an averaging processing unit calculating, when executing the demodulating process of the packet signal at a certain timeslot allocated to the target terminal, an average value of the parameters from the parameter obtained from the packet signal and from the parameters stored in the storage unit and obtained from the packet signals at one or more timeslots allocated to the target terminal and discontinuous from the certain timeslot, and outputting the average value as the parameter used for the demodulating process.

10. A wireless terminal according to claim 9, further comprising a determining unit determining the plurality of parameters used for calculating the average value in the averaging processing unit on the basis of slot allocation information representing a relationship between the plurality of timeslots and the wireless terminals allocated to the respective timeslots.

11. A wireless terminal according to claim 9, wherein the one or more timeslots discontinuous from the certain timeslot are positioned within a predetermined time range centering at the certain timeslot.

12. A wireless terminal according to claim 9, further comprising a weighting unit weighting, by the standard of the parameter corresponding to the certain timeslot, the plurality of parameters for calculating the average value.

13. A wireless terminal according to claim 12, wherein the weighting unit applies a heaviest weight to the parameter corresponding to the certain timeslot, and applies a weight getting smaller as a time interval from the certain timeslot becomes larger to the parameter corresponding to the one or more timeslots.

14. A wireless terminal according to claim 9, wherein the parameter is a channel estimation value of a packet signal.

15. A wireless terminal according to claim 9, wherein the parameter is a frequency offset estimation value between the wireless base station and the wireless terminal.

16. A wireless terminal according to claim 9, wherein the parameter is an arrival direction estimation value of the packet signal.

17. A wireless terminal according to claim 10, wherein the slot allocation information is received via a channel different from the transmission channel for the packet signal.

18. A wireless terminal according to claim 10, wherein the slot allocation information embedded in the packet signal is received.