Time slot and carrier frequency allocation in a network

• US 7,423,992 B2
• Filed: 07/09/2003
• Issued: 09/09/2008
• Est. Priority Date: 04/16/2003
• Status: Expired due to Fees

• Current Assignee: Sony Corporation (Sony Group Corp.), Sony Electronics Inc. (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.), Sony Electronics Inc. (Sony Group Corp.)
• Inventors: Iwamura, Ryuichi
• Primary Examiner(s): Shah; Chirag G
• Assistant Examiner(s): Rivas; Salvador E
• Application Number:
  US10/616,344
• Publication Number:
  US 20040208139A1
• Time in Patent Office: 1,889 Days
• Field of Search: 370/310, 375/336
• US Class Current: 370/330
• CPC Class Codes: H04B 2203/5408 using protocols
• CPC Class Codes: H04B 2203/545 Audio/video application, e.g. interphone
• CPC Class Codes: H04B 3/544 Setting up communications; Call and signalling arrangements
• CPC Class Codes: H04B 7/2618 using hybrid code-time division multiple access [CDMA-TDMA]
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0044 allocation of payload
• CPC Class Codes: H04L 5/006 Quality of the received signal, e.g. BER, SNR, water filling

Abstract

In an OFDM-TDMA power line communication system, time slot and carrier frequencies are assigned in a manner that reallocates time slots and carrier frequencies to enhance the efficiency of utilization of bandwidth. The reassignments are communicated between transmitting and receiving stations by transmitting tone maps that designate the reassignment of the time slots and carriers. Several variations are presented depending upon the circumstances of channel use and prior assignment of time slots and channels.

Claims

1. A time slot and carrier allocation method for time division multiple access (TDMA) multiple carrier communications, comprising:

determining from a tone map that first and second time slots are generally allocated to a first and a second receiver respectively;

determining from the tone map that the first and second receivers are able to receive using a common set of carriers;

determining that a single data stream is to be transmitted to the first and second receivers;

transmitting a new tone map to the first and second receivers that specifies that the first and second receivers are to receive the single data stream using the common set of carriers during one or more designated time slots;

wherein the number of common carriers is greater than a threshold number of available carriers, and wherein the threshold number comprises approximately 50% of available carriers; and

wherein a number of unused carriers allocated to the control stream of data is less than a specified maximum, and the specified maximum comprises approximately 10% of available carriers.

2. The time slot and carrier allocation method according to claim 1, further comprising transmitting a control stream of data to the first and second receivers using the common carrier.

3. The time slot and carrier allocation method according to claim 1, wherein the single stream of data comprises audio/video data.

4. The time slot and carrier allocation method according to claim 1, wherein the communication comprises an Orthogonal Frequency Division Multiplexed TDMA communication.

5. The time slot and carrier allocation method according to claim 1, wherein the new tone map specifies that an unused carrier is to be reallocated to a plurality of other streams of data.

6. The time slot and carrier allocation method according to claim 1, further comprising transmitting the single data steam using the common set of carriers during the designated time slots.

7. The time slot and carrier allocation method according to claim 1, wherein the tone map designates that the first and second receivers receive the single data stream using merged time slots.

8. An electronic storage medium storing instructions which, when executed on a programmed processor, carry out a time slot and carrier allocation method according to claim 1.

9. The method according to claim 1, wherein the communication is carried out in a power line communication system.

10. A time slot and carrier allocation method for time division multiple access (TDMA) multiple carrier communications, comprising:

determining from a tone map that first and second time slots are generally allocated to a first and a second receiver respectively;

determining from the tone map that the first and second receivers are able to receive using a common set of carriers;

determining that a single data stream is to be transmitted to the first and second receivers;

transmitting a new tone map to the first and second receivers that specifies that the first and second receivers are to receive the single data stream using the common set of carriers during one or more designated time slots, wherein the new tone map specifics that an unused carrier is to be reallocated to a plurality of other streams of data;

transmitting the single data stream using the common set of carriers during the designated time slots;

transmitting a control stream of data to the first and second receivers using the common carrier; and

wherein the number of common carriers is greater than a threshold number of available carriers, and wherein the threshold number comprises approximately 50% of available carriers, and wherein the tone map designates that the first and second receivers receive the single data stream using merged time slots, and wherein the single stream of data comprises audio/video data; and

wherein a number of unused carriers allocated to the control stream of data is less than a specified maximum, and wherein the specified maximum comprises approximately 10% of available carriers, and wherein the communication comprises an Orthogonal Frequency Division Multiplexed TDMA power line communication.

11. The method according to claim 10, wherein the communication is carried out in a power line communication system.

12. An electronic storage medium storing instructions which, when executed on a programmed processor, carry out a time slot and carrier allocation method according to claim 10.