Method for reducing signaling overhead in a multicarrier system with dynamic bit allocation and corresponding transmitter/receiver device

• US 7,460,465 B2
• Filed: 04/27/2001
• Issued: 12/02/2008
• Est. Priority Date: 04/27/2001
• Status: Expired due to Term

• Current Assignee: Gigaset Communications GmbH (Gigaset AG)
• Original Assignee: Siemens AG
• Inventors: Gröting, Wolfgang, Bolinth, Edgar, Kern, Ralf, Lombardi, Giancarlo
• Primary Examiner(s): Cho; Hong Sol
• Application Number:
  US10/476,280
• Publication Number:
  US 20040174808A1
• Time in Patent Office: 2,776 Days
• Field of Search: 370/206, 370/208, 370/237, 370/238, 370/260, 375/222, 375/260, 709238-242
• US Class Current: 370/206
• 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 5/0094 Indication of how sub-channels of the path are allocated

Abstract

A method for reducing signaling overhead in a multicarrier system with dynamic bit allocation per subcarrier and a corresponding transmitter/receiver device, are provided wherein an established bit allocation table (BAT) that is provided with an index (I) is stored in a BAT storage device (LUT). In order to reduce signaling overhead, only the corresponding index (I) of an existing bit allocation table is transmitted (S6).

Claims

1. A method for reducing signaling overhead in a multicarrier system with dynamic bit allocation, the method comprising the steps of:

establishing transmission characteristics of a transmission channel;

establishing a bit allocation table based on the established transmission characteristics;

comparing the established bit allocation table with bit allocation tables stored and indexed in a storage device;

determining if the established bit allocation table corresponds to one of the stored bit allocation tables and, if so, transmitting only an index of the corresponding stored bit allocation table to implement a bit allocation table alignment during signaling; and

determining if the established bit allocation table does not correspond to one of the stored bit allocation tables and, if not, performing the additional step of;

verifying a number of bit allocation tables stored in the storage device and, if a maximum number of bit allocation tables stored in the storage device is exceeded, performing the additional steps of;

determining a difference in respect of a subsequent stored bit allocation table; and

transmitting both the difference and the index of the subsequent stored bit allocation table.

2. A method for reducing signaling overhead in a multicarrier system with dynamic bit allocation as claimed in claim 1, wherein if the maximum number of bit allocation tables stored in the storage device is not exceeded, the following additional steps are performed:

storing the established bit allocation table in the storage device and assigning an index; and

transmitting the established bit allocation table with the assigned index to implement a bit allocation table alignment during signaling.

3. A method for reducing signaling overhead in a multicarrier system with dynamic bit allocation as claimed in claim 1, wherein if the established bit allocation table does not correspond to one of the stored bit allocation tables, the following additional steps are performed:

storing the established bit allocation table in the storage device and assigning an index; and

transmitting the established bit allocation table with the assigned index to implement a bit allocation table alignment during signaling.

4. A method for reducing signaling overhead in a multicarrier system with dynamic bit allocation as claimed in claim 1, wherein the bit allocation tables comprise a plurality of subcarriers and a plurality of corresponding bit values per subcarrier.

5. A method for reducing signaling overhead in a multicarrier system with dynamic bit allocation as claimed in claim 1, wherein the bit allocation tables comprise a plurality of subcarrier groups and a plurality of corresponding group bit values per subcarrier group.

6. A method for reducing signaling overhead in a multicarrier system with dynamic bit allocation as claimed in claim 1, wherein the bit allocation tables are used to implement adaptive modulation.

7. A method for reducing signaling overhead in a multicarrier system with dynamic bit allocation as claimed in claim 1, wherein the multicarrier system is at least one of an OFDM, an MC-CDMA and a CDMA data transmission system.

8. A method for reducing signaling overhead in a multicarrier system with dynamic bit allocation as claimed in claim 1, wherein the storage device comprises a domain with permanently predefined bit allocation tables.

9. A receiver device for reducing signaling overhead in a multicarrier system with dynamic bit allocation, comprising:

a bit loading device for generating bit allocation tables based on established channel characteristics;

a receiver controlled unit for analyzing the generated bit allocation tables; and

a storage device for storing a number of bit allocation tables as well as an index for each bit allocation table;

wherein the receiver control unit only outputs an index for transmission to implement a bit allocation table alignment during signaling if the generated bit allocation table corresponds to a bit allocation table stored in the storage device, and adjustment to modified channel characteristics is carried out based on the generated bit allocation table, with the receiver control unit verifying a number of bit allocation tables stored in the storage device and, if a maximum number of bit allocation tables stored in the storage device is exceeded, determining a difference in respect of a subsequent stored bit allocation table and outputting the index of the subsequent bit allocation table and the difference in respect of the subsequent stored bit allocation table for transmission to implement a bit allocation table alignment during signaling.

10. A receiver device for reducing signaling overhead in a multicarrier system with dynamic bit allocation as claimed in claim 9, wherein the receiver control unit stores the generated bit allocation table with a corresponding index in the storage device and outputs the generated bit allocation table with the corresponding index for transmission to implement a bit allocation table alignment during signaling if the generated bit allocation table does not correspond to any bit allocation table stored in the storage device.

11. A receiver device for reducing signaling overhead in a multicarrier system with dynamic bit allocation as claimed in claim 9, wherein the multicarrier system is at least one of an OFDM, an MC-CDMA and a CDMA data transmission system.

12. A receiver device for reducing signaling overhead in a multicarrier system with dynamic bit allocation as claimed in claim 9, wherein adjustment to the modified channel characteristics occurs via an adaptive modulation device.