Method and apparatus for updating carrier channel allocations

• US 5,521,906 A
• Filed: 01/26/1995
• Issued: 05/28/1996
• Est. Priority Date: 01/26/1995
• Status: Expired due to Term

• Current Assignee: Apple Inc.
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Markison, Timothy W., Grube, Gary W., Rybicki, Mathew A., Pendleton, Matthew A.
• Primary Examiner(s): MARCELO, MELVIN C
• Application Number:
  US08/378,846
• Time in Patent Office: 488 Days
• Field of Search: 370/17, 370/50, 370/69.1, 370/120, 370/121, 370/124, 370/76, 370/79, 370/80
• US Class Current: 370/252
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0046 Determination of how many bits are transmitted on different sub-channels
• CPC Class Codes: H04L 5/0064 Rate requirement of the data, e.g. scalable bandwidth, data priority
• CPC Class Codes: H04L 5/0087 when data requirements change
• CPC Class Codes: H04L 5/0094 Indication of how sub-channels of the path are allocated

Abstract

In a communication system that utilizes DMT technology to couple a primary site (102) to a plurality of secondary sites (104-108), carrier channel allocations may be updated as follows. At periodic intervals, the primary site requests updating bit loading information from the secondary sites. Upon receiving the updated bit loading information, the primary site (102) determines an updated call bit loading table for each active call. From this, the primary site (102) determines whether current carrier channel allocation provides sufficient bandwidth. When the current carrier channel allocation does not provide the sufficient bandwidth, the primary site modifies the current carrier channel allocation to meet the bandwidth requirements.

Claims

1. A method of updating carrier channel allocation, the method comprising the steps of:

a) receiving updated bit loading information from a plurality of sites;

for each call allocation;

b) determining an updated call bit loading table;

c) determining, based on the updated call bit loading table, whether current carrier channel allocation provides sufficient bandwidth; and

d) when the current carrier channel allocation does not provide the sufficient bandwidth, modifying the current carrier channel allocation when carrier channel resources are available.

2. The method of claim 1, wherein step (a) further comprises receiving the updated bit loading information in a form of updated site bit loading tables.

3. The method of claim 2, wherein step (b) further comprises utilizing the updated site bit loading tables to create the updated call bit loading table.

4. The method of claim 1, wherein step (a) further comprises receiving a bit loading change message as the updated bit loading information.

5. The method of claim 4, wherein step (b) further comprises:

generating, for each site involved in a particular call, a new site bit loading table based on the bit loading change message; and

from the new site bit loading table of each site involved in the particular call, generating the updated call bit loading table.

6. The method of claim 1, wherein step (b) further comprises:

accessing a site location database, wherein the site location database stores, for a particular call, sites of the plurality of sites that support the particular call;

generating, for each site that support the particular call, an updated site bit loading table to produces a set of updated site bit loading tables; and

from the set of the updated site bit loading tables, producing the updated call bit loading table.

7. The method of claim 6, wherein the step of producing the updated call bit loading table further comprises:

for each carrier channel entry in the set of the updated site bit loading tables, comparing bit loading; and

entering lowest bit loading of the comparing into the updated call bit loading table.

8. The method of claim 1, wherein step (c) further comprises:

accessing a call bit rate database to determine bit loading requirements for a particular call;

accessing a channel allocation database to identify at least one carrier channel allocated to the particular call;

from the updated call bit loading table, determining bit loading of the at least one carrier channel;

comparing the bit loading of the at least one carrier channel with the bit loading requirements; and

when the bit loading for the at least one carrier channel is less than the bit loading requirements, determining that the current carrier channel allocation does not provide sufficient bandwidth.

9. The method of claim 8 further comprises:

when the bit loading for the at least one carrier channel is greater than the bit loading, determining that the current carrier channel allocation provides the sufficient bandwidth;

adjusting the bit loading of the at least one carrier channel to match the bit loading requirements; and

indicating in the channel allocation database a number of bit reduction for the at least one carrier channel.

10. The method of claim 8 further comprises, when the bit loading for the at least one carrier channel is greater than the bit loading, determining that the current carrier channel allocation provides the sufficient bandwidth.

11. The method of claim 8, wherein step (d) further comprises:

accessing the carrier channel allocation database to determine a bit reduction for the at least one carrier channel;

when the bit reduction is at least one bit, determining whether the bit reduction plus the bit loading for the at least one carrier channel is equal to or greater than the bit loading requirements; and

when the bit reduction plus the bit loading for the at least one carrier channel is equal to or greater than the bit loading requirements, increasing the bit loading of the at least one carrier channel to match the bit loading requirements.

12. The method of claim 11 further comprises, when the bit reduction plus the bit loading for the at least one carrier channel is equal to or greater than the bit loading requirements, reducing the bit reduction by a number of bits added to the bit loading of the at least one carrier channel.

13. The method of claim 11 further comprises, when the bit reduction plus the bit loading for the at least one carrier channel is less than the bit loading requirements;

adding the bit reduction to the bit loading of the at least one carrier channel to produce updated bit loading of the at least one carrier channel;

determining a bit loading difference between the updated bit loading of the at least one carrier channel and the bit loading requirements;

when the bit loading difference is greater than one bit, determining, from the carrier channel allocation database, whether at least one available carrier channel has a bit loading at least equal to the bit loading difference; and

when the at least one available carrier channel has the bit loading at least equal to the bit loading difference, allocating the at least one available carrier channel to the particular call.

14. The method of claim 13 further comprises, when the bit loading difference is one bit;

determining, from the carrier channel allocation database, whether an available carrier channel has a bit loading of at least two bits;

when the available carrier channel has the bit loading of at least two bits, allocating the available carrier channel to the particular call; and

reducing the updated bit loading of the at least one carrier channel by one bit.

15. The method of claim 11, further comprises, when the bit reduction is zero;

determining a bit loading difference between the bit loading of the at least one carrier channel and the bit loading requirements;

when the bit loading difference is greater than one bit, determining, from the carrier channel allocation database,

whether at least one available carrier channel has a bit loading at least equal to the bit loading difference; and

when the at least one available carrier channel has the bit loading at least equal to the bit loading difference, allocating the at least one available carrier channel to the particular call.

16. The method of claim 1, wherein step (d) further comprises:

determining from a carrier channel allocation database whether additional bits are available for allocation to a particular call; and

when the additional bits are available for allocation, determining that the carrier channel resources are available.

17. The method of claim 16 further comprises, when additional bits are not available for allocation to the particular call, determining that the carrier channel resources are not available.

18. A method for updating carrier channel allocation for an infrastructure control channel, the method comprising the steps of:

a) obtaining updated bit loading information from a plurality of sites;

b) determining an updated control channel bit loading table from the updated bit loading information;

c) determining, based on the updated control channel bit loading table, whether current carrier channel allocation to the infrastructure control channel has reduced bit loading; and

d) when the current carrier channel allocation has the reduced bit loading, modifying the current carrier channel allocation.

19. The method of claim 18, wherein step (c) further comprises:

comparing bit loading of a carrier channel entry in a current control channel bit loading table with the bit loading of a corresponding carrier channel entry in the updated control channel bit loading table;

when the bit loading of the corresponding carrier channel entry differs from the bit loading of the carrier channel entry in the current control channel bit loading table, identifying a difference;

when the difference is for a carrier channel allocated to the infrastructure control channel, determining whether the difference is an increase bit loading or a decrease bit loading; and

when the difference is the decrease bit loading, determining that the current carrier channel allocation has the reduced bit loading.

20. The method of claim 19, wherein step (d) further comprises:

determining whether the carrier channel allocated to the infrastructure control channel has an affiliated bit reduction greater than zero bits; and

when the affiliated bit reduction is greater than zero, increasing the bit loading of the carrier channel by the affiliated bit reduction to modify the current carrier channel allocation.

21. The method of claim 20 further comprises, when the affiliated bit reduction is not greater than zero bits;

determining whether another carrier channel is available;

when the another carrier channel is available, allocating the another carrier channel to the infrastructure control channel; and

updating a carrier channel allocation database.

22. The method of claim 21 further comprises, when another carrier channel is not available;

terminating a low priority carrier channel allocation to produce an available carrier channel;

allocating the available carrier channel to the infrastructure control channel; and

updating the carrier channel allocation database.

23. The method of claim 20 further comprises:

determining whether the increasing of the bit loading of the carrier channel meets bit loading requirements for the infrastructure control channel;

when the increasing does not meet the bit loading requirements, allocating another carrier channel to the infrastructure control channel; and

updating a carrier channel allocation database.

24. The method of claim 19 further comprises, when the difference is the increase bit loading;

determining whether bit loading requirements of the infrastructure control channel can be fulfilled with fewer carrier channels;

when the bit loading requirements can be fulfilled with fewer carrier channels, reallocating carrier channels to the infrastructure control channel; and

updating a carrier channel allocation database.

25. An apparatus for updating carrier channel allocations of a communication system infrastructure, the apparatus comprising:

memory that stores bit loading information, updated bit loading information, and carrier channel allocation information; and

processor, operably coupled to the memory, that compares the bit loading information and updated bit loading information and identifies differences and that determines, based on the differences, carrier channel allocation modifications and updates the carrier channel allocation information with the carrier channel allocation modifications.