Band control method and communication apparatus

• US 8,045,580 B2
• Filed: 03/30/2006
• Issued: 10/25/2011
• Est. Priority Date: 04/04/2005
• Status: Active Grant

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Ohata, Keiichi, Ito, Masaharu, Maruhashi, Kenichi, Morimoto, Takao, Kishimoto, Shuya, Hamada, Yasuhiro
• Primary Examiner(s): Phillips; Hassan
• Assistant Examiner(s): CATTUNGAL, AJAY P
• Application Number:
  US11/910,572
• Publication Number:
  US 20090238206A1
• Time in Patent Office: 2,035 Days
• Field of Search: None
• US Class Current: 370/468
• CPC Class Codes: H04B 1/50 using different frequencies for the two directions of communication
• CPC Class Codes: H04J 3/1694 Allocation of channels in TDM/TDMA networks, e.g. distributed multiplexers Passive Optical Networks H04Q11/0062
• CPC Class Codes: H04L 5/0037 Inter-user or inter-terminal allocation
• CPC Class Codes: H04L 5/143 for modulated signals H04L5/1469 takes precedence

Abstract

The present invention intends to improve communication efficiency between two communication apparatuses each engaged in the communication by full duplex communication method by using a surplus band of the one to transmission band of the other. A first bandwidth required by a first communication apparatus (A) at data transmission and a second bandwidth required by a second communication apparatus (B) at data transmission are presumed. Next, the first bandwidth presumed as mentioned is compared to a first bandwidth used which the first communication apparatus (A) currently uses and at the same time, the second bandwidth presumed as mentioned is compared to a second bandwidth used which the second communication apparatus (B) currently uses. The first bandwidth and the second bandwidth are then adjusted, and a third bandwidth which the first communication apparatus (A) uses at data transmission and a fourth bandwidth which the second communication apparatus (B) uses are determined.

Claims

1. A frequency bandwidth control method for controlling a frequency bandwidth when a first communication apparatus and a second communication apparatus communicate with full duplex by using two or more divided frequency bandwidths within a previously allocated whole frequency bandwidth, wherein

frequency bandwidths which said first communication apparatus and said second communication apparatus use at data transmission are different frequency bandwidths, the bandwidth control method comprising the steps of:

a bandwidth presumption step for presuming a first bandwidth required by said first communication apparatus at data transmission and a second bandwidth required by said second communication apparatus at data transmission;

a bandwidth comparison step for comparing said first bandwidth with a first bandwidth used which said first communication apparatus currently uses and comparing said second bandwidth with a second bandwidth used which said second communication apparatus currently uses; and

a bandwidth used determination step for determining a third bandwidth used by said first communication apparatus at data transmission and a fourth bandwidth used by said second communication apparatus at data transmission according to comparison results obtained by said bandwidth comparison step, wherein said determining said third bandwidth and said fourth bandwidth comprises;

if said first bandwidth is less than said first bandwidth used and said second bandwidth is greater than said second bandwidth used, determining said third bandwidth to be equal to said first bandwidth and determining said fourth bandwidth to be equal to said whole frequency bandwidth less said third bandwidth,

if said first bandwidth is greater than said first bandwidth used and said second bandwidth is less than said second bandwidth used, determining said fourth bandwidth to be equal to said second bandwidth and determining said third bandwidth to be equal to said whole frequency bandwidth less said fourth bandwidth,

if said first bandwidth is greater than said first bandwidth used and said second bandwidth is greater than said second bandwidth used, determining said third bandwidth and said fourth bandwidth such that a ratio of said first bandwidth to said second bandwidth is the same as a ratio of said third bandwidth to said fourth bandwidth, and

if said first bandwidth is less than or equal to said first bandwidth used and said second bandwidth is less than or equal to said second bandwidth used, determining said third bandwidth to be equal to said first bandwidth used and determining said fourth bandwidth to be equal to said second bandwidth used;

a first communication step for transmitting data by using said third bandwidth and for receiving data by using said fourth bandwidth, in said first communication apparatus; and

a second communication step for transmitting data by using said fourth bandwidth and for receiving data by using said third bandwidth, in said second communication apparatus.

2. The bandwidth control method according to claim 1, wherein in said bandwidth presumption step, said first communication apparatus presumes said first bandwidth and said second communication apparatus presumes said second bandwidth.

3. The bandwidth control method according to claim 1, wherein in said bandwidth comparison step, said first communication apparatus acquires said second bandwidth from said second communication apparatus, said first communication apparatus compares said first bandwidth with said first bandwidth used and further compares said second bandwidth with said second bandwidth used.

4. The bandwidth control method according to claim 1, wherein in said bandwidth used determination step, said first communication determines said third bandwidth and said fourth bandwidth according to the comparison results.

5. The bandwidth control method according to claim 1, wherein said bandwidth presumption step presumes said first bandwidth and said second bandwidth periodically every predetermined time interval.

6. The bandwidth control method according to claim 1, wherein said bandwidth presumption step presumes said first bandwidth and said second bandwidth only when, in at least either of said first communication apparatus and said second communication apparatus, an amount of data scheduled to be transmitted is less than a predetermined threshold level through a predetermined time.

7. The bandwidth control method according to claim 1, wherein, in at least either of said first communication apparatus and said second communication apparatus, priority is put to data scheduled to be transmitted, and said bandwidth presumption step adds virtual data which are not transmitted actually according to said priority and presumes said first bandwidth and said second bandwidth.

8. The bandwidth control method according to claim 1, wherein said first communication apparatus and said second communication apparatus modulate directly a carrier frequency by a transmission data to allow data transmission.

9. The bandwidth control method according to claim 1, wherein said first communication apparatus and said second communication apparatus perform single side band amplitude modulation of a carrier frequency after an intermediate frequency is modulated by the transmission data to allow data transmission.

10. The bandwidth control method according to claim 1, wherein said first communication apparatus and said second communication apparatus adjust a number of carriers for multicarrier modulation utilizing multicarrier modulation and based on said third bandwidth and said fourth bandwidth to allow data transmission.

11. The bandwidth control method according to claim 1, wherein in said bandwidth used determination step determining said third bandwidth further comprises determining a center frequency of said third bandwidth, and determining said fourth bandwidth further comprises determining a center frequency of said fourth bandwidth.

12. A communication apparatus for performing data transmission by controlling frequency bandwidth when data communication is performed with an other communication apparatus with full duplex by using two or more divided frequency bandwidths within a previously allocated whole frequency bandwidth, wherein

frequency bandwidths which said communication apparatus and said other communication apparatus use at data transmission are different frequency bandwidths, the communication apparatus comprising:

bandwidth presumption means for presuming a first bandwidth which is required by said communication apparatus at data transmission;

bandwidth acquisition means for acquiring a second bandwidth from said other communication apparatus which is required by said other communication apparatus at data transmission;

bandwidth comparison means for comparing said first bandwidth with a first bandwidth used which said first communication apparatus currently uses, and comparing said second bandwidth with a second bandwidth used which said second communication apparatus currently uses; and

bandwidth used determination means for determining a third bandwidth used by said first communication apparatus at data transmission and a fourth bandwidth used by said second communication apparatus at data transmission according to comparison results obtained by said bandwidth comparison means, wherein said third bandwidth and said fourth bandwidth are determined such that;

if said first bandwidth is less than said first bandwidth used and said second bandwidth is greater than said second bandwidth used, said third bandwidth is determined to be equal to said first bandwidth and said fourth bandwidth is determined to be equal to said whole frequency bandwidth less said third bandwidth,

if said first bandwidth is greater than said first bandwidth used and said second bandwidth is less than said second bandwidth used, said fourth bandwidth is determined to be equal to said second bandwidth and said third bandwidth is determined to be equal to said whole frequency bandwidth less said fourth bandwidth,

if said first bandwidth is greater than said first bandwidth used and said second bandwidth is greater than said second bandwidth used, said third bandwidth and said fourth bandwidth are determined such that a ratio of said first bandwidth to said second bandwidth is the same as a ratio of said third bandwidth to said fourth bandwidth, and

if said first bandwidth is less than or equal to said first bandwidth used and said second bandwidth is less than or equal to said second bandwidth used, said third bandwidth is determined to be equal to said first bandwidth used and said fourth bandwidth is determined to be equal to said second bandwidth used,

wherein said communication apparatus transmits data by using said third bandwidth and receives data by using said fourth bandwidth and said other communication apparatus transmits data by using said fourth bandwidth and receives data by using said third bandwidth.

13. The communication apparatus according to claim 12, wherein said bandwidth used determination means further determines said third bandwidth, a center frequency of said third bandwidth and a center frequency of said fourth bandwidth.

14. The communication apparatus according to claim 13 comprising:

transmission means for transmitting data to said other communication apparatus using said third bandwidth and the center frequency of said third bandwidth; and

reception means for receiving a data from said other communication apparatus using said fourth bandwidth and the center frequency of said fourth bandwidth.

15. The communication apparatus according to claim 12, wherein said bandwidth presumption means presumes periodically said first bandwidth every predetermined time interval.

16. The communication apparatus according to claim 12, wherein said bandwidth presumption means presumes said first bandwidth only when, in at least either of said communication apparatus and said other communication apparatus, an amount of data scheduled to be transmitted is less than a predetermined threshold level through a predetermined time.

17. The communication apparatus according to claim 12, wherein, in at least either of said communication apparatus and said other communication apparatus, priority is put to data scheduled to be transmitted, and said bandwidth presumption means adds virtual data which are not transmitted actually according to said priority and presumes said first bandwidth.

18. The communication apparatus according to claim 12, wherein a carrier frequency is directly modulated by transmission data to allow data transmission.

19. The communication apparatus according to claim 12, wherein a carrier frequency is single side band amplitude modulated after a intermediate frequency is modulated by the transmission data to allow data transmission.

20. The communication apparatus according to claim 12, wherein a number of carriers for multicarrier modulation is adjusted utilizing multicarrier modulation and based on said third bandwidth and said fourth bandwidth to allow data transmission.