Wireless transport framework with variable frequency domain training

• US 9,009,761 B2
• Filed: 11/12/2013
• Issued: 04/14/2015
• Est. Priority Date: 07/05/2007
• Status: Active Grant

• Current Assignee: Coherent Logix, Incorporated
• Original Assignee: Coherent Logix, Incorporated
• Inventors: Shelby, Kevin A., Nysen, Peter J., Doerr, Michael B.
• Primary Examiner(s): HANCE, ROBERT J
• Application Number:
  US14/077,382
• Publication Number:
  US 20140075489A1
• Time in Patent Office: 518 Days
• Field of Search: 725/62
• US Class Current: 725/62
• CPC Class Codes: H03M 13/1102 Codes on graphs and decoding on graphs, e.g. low-density parity check [LDPC] codes
• CPC Class Codes: H03M 13/2732 Convolutional interleaver; Interleavers using shift-registers or delay lines like, e.g. Ramsey type interleaver
• CPC Class Codes: H03M 13/29 combining two or more codes or code structures, e.g. product codes, generalised product codes, concatenated codes, inner and outer codes
• CPC Class Codes: H03M 13/2906 using block codes H03M13/2957 takes precedence
• CPC Class Codes: H03M 13/2909 Product codes
• CPC Class Codes: H03M 13/2936 comprising an outer Reed-Solomon code and an inner convolutional code
• CPC Class Codes: H03M 13/2957 Turbo codes and decoding
• CPC Class Codes: H03M 13/6583 Normalization other than scaling, e.g. by subtraction
• CPC Class Codes: H04J 11/00 Orthogonal multiplex systems, e.g. using WALSH codesH04J13/00 takes precedence
• CPC Class Codes: H04L 25/02 Details ; arrangements for supplying electrical power along data transmission lines systems for transmitting signals via power distribution lines H04B3/54
• CPC Class Codes: H04L 27/261 Details of reference signals
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/005 of common pilots, i.e. pilots destined for multiple users or terminals
• CPC Class Codes: H04L 65/611 for multicast or broadcast systems for broadcast or conference H04L12/18; arrangements for broadcast or distribution combined with broadcast H04H20/00; arrangements for broadcast applications with a direct linkage to broadcast information or to broadcast space-time H04H60/00; selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS], H04W4/06
• CPC Class Codes: H04N 21/23605 Creation or processing of packetized elementary streams [PES]
• CPC Class Codes: H04N 21/2381 Adapting the multiplex stream to a specific network, e.g. an Internet Protocol [IP] network transmission of MPEG streams over ATM H04L12/5601
• CPC Class Codes: H04N 21/2383 Channel coding or modulation of digital bit-stream, e.g. QPSK modulation arrangements for detecting or preventing errors in the information received by adapting the channel coding H04L1/0009; analogue front ends or means for connecting modulators, demodulators or transceivers to a transmission line H04L27/0002
• CPC Class Codes: H04N 21/2389 Multiplex stream processing, e.g. multiplex stream encrypting
• CPC Class Codes: H04N 21/2402 Monitoring of the downstream path of the transmission network, e.g. bandwidth available traffic monitoring in data switching networks H04L43/00; monitoring data switching networks utilization H04L43/0876
• CPC Class Codes: H04N 21/251 Learning process for intelligent management, e.g. learning user preferences for recommending movies details of learning user preferences for the retrieval of video data in a video database G06F16/739; computer systems using learning methods G06N3/08
• CPC Class Codes: H04N 21/41407 : embedded in a portable device, e.g. video client on a mobile phone, PDA, laptop constructional details of equipment or arrangements specially adapted for portable computer application G06F1/1626; arrangements specially adapted for mobile receivers in broadcast systems H04H20/57
• CPC Class Codes: H04N 21/4381 : Recovering the multiplex stream from a specific network, e.g. recovering MPEG packets from ATM cells transmission of MPEG streams over ATM H04L12/5601
• CPC Class Codes: H04N 21/4382 : Demodulation or channel decoding, e.g. QPSK demodulation analog front ends or means for connecting modulators, demodulators or transceivers to a transmission line H04L27/0002
• CPC Class Codes: H04N 21/4385 : Multiplex stream processing, e.g. multiplex stream decrypting
• CPC Class Codes: H04N 21/6131 : involving transmission via a mobile phone network wireless downlink channel access H04W74/006
• CPC Class Codes: H04N 21/6181 : involving transmission via a mobile phone network arrangements for providing broadcast or conference services to substation in data switching networks in combination with wireless systems H04L12/189; wireless uplink channel access H04W74/004
• CPC Class Codes: H04N 21/64315 : DVB-H
• CPC Class Codes: H04N 21/64322 : IP
• CPC Class Codes: H04N 21/6437 : Real-time Transport Protocol [RTP]
• CPC Class Codes: H04W 72/20 : Control channels or signalling for resource management
• CPC Class Codes: H04W 72/30 : Resource management for broadcast services

Abstract

A system and method for wirelessly transmitting audiovisual information. Training information may be stored in a memory. A plurality of packets may be generated, including the training information. The plurality of packets may also include audiovisual information. The plurality of packets may include first information identifying a first training pattern of a plurality of possible training patterns. The first training pattern may specify one or more locations of the training information in the plurality of packets. The first information may be usable by a receiver to determine the first training pattern of the plurality of possible training patterns. The plurality of packets may be transmitted in a wireless manner.

Claims

1. A method for broadcasting audiovisual information to mobile devices in a wireless manner, wherein the mobile devices comprise receivers, the method comprising:

storing training information in a memory;

generating a plurality of packets, wherein a first portion of the plurality of packets comprises the training information, wherein an amount of the training information depends on a time of day, wherein the amount is greater at times when more receivers are likely to be moving;

wherein at least one of the plurality of packets comprises first information which identifies a first training pattern of a plurality of possible training patterns, wherein the first training pattern specifies one or more locations of the training information in the plurality of packets;

wherein the plurality of packets further comprise audiovisual information;

wherein the first information is useable by the receiver to determine the first training pattern of the plurality of possible training patterns;

transmitting the plurality of packets on a signal modulated in the frequency domain in a wireless manner.

2. The method of claim 1,

wherein the signal is an orthogonal frequency division modulation (OFDM) signal, wherein the OFDM signal comprises a plurality of symbols each having a plurality of sub carriers.

3. The method of claim 2,

wherein said generating the plurality of packets with the amount of training information depending on the time of day comprises varying the ratio of training subcarriers to data subcarriers in the OFDM signal.

4. The method of claim 1,

wherein each of the plurality of possible training patterns specifies a different amount of training information.

5. The method of claim 1,

wherein each of the plurality of possible training patterns specifies a different subset of a plurality of subcarriers of the signal modulated in the frequency domain as training subcarriers.

6. The method of claim 1,

wherein a subset of the plurality of packets comprises control information, wherein the first information is located in the subset of the plurality of packets comprising the control information.

7. A system for broadcasting content to mobile devices in a wireless manner, the system comprising:

transmit logic configured to;

select a training pattern of a plurality of possible training patterns,

wherein each of the plurality of possible training patterns comprises a different amount of training information, wherein the training pattern is selected at least in part based on a time of day, wherein a training pattern having a greater amount of training information is selected at times when more mobile devices are likely to be moving; and

generate a plurality of packets using the selected training pattern, wherein the plurality of packets comprise content and control information, wherein the control information comprises an indication of the training pattern used in the plurality of packets,

wherein the plurality of packets are configured to be transmitted in a wireless manner using a frequency domain modulated signal.

8. The system of claim 7,

wherein the signal modulated in the frequency domain comprises an orthogonal frequency division modulation (OFDM) signal, wherein the OFDM signal comprises a plurality of symbols each having a plurality of subcarriers.

9. The system of claim 7,

wherein each possible training pattern comprises a different ratio of pilot to data subcarriers of the frequency domain modulated signal.

10. The system of claim 7,

wherein each possible training pattern specifies a different subset of a plurality of subcarriers of the frequency domain modulated signal as pilot tones.

11. The system of claim 7, wherein the system further comprises:

a transmitter coupled to the transmit logic, wherein the transmitter is configured to transmit the plurality of packets in a wireless manner using the frequency domain modulated signal.

12. The system of claim 7,

wherein the content comprises audiovisual information.

13. The system of claim 7,

wherein the content comprises textual information.

14. The system of claim 7,

wherein the indication of the training pattern comprises an orthogonal gold code, wherein each of a plurality of orthogonal gold codes correspond to each of the plurality of possible training patterns.

15. A non-transitory computer readable memory medium storing program instructions for generating packets for transmitting content to one or more receivers in a wireless manner, wherein the program instructions are executable to:

generate a plurality of packets, wherein a first portion of the plurality of packets comprises training information, wherein an amount of the training information depends on a time of day, wherein the amount is greater at times when more receivers are likely to be moving;

wherein at least one of the plurality of packets comprises first information which identifies a first training pattern of a plurality of possible training patterns, wherein the first training pattern specifies one or more locations of the training information in the plurality of packets;

wherein the plurality of packets further comprise content information;

wherein the first information is useable by the one or more receivers to determine the first training pattern of the plurality of possible training patterns;

wherein the plurality of packets are configured to be transmitted to the one or more receivers in a wireless manner using a frequency domain modulated signal.

16. The memory medium of claim 15,

wherein the signal is an orthogonal frequency division modulation (OFDM) signal, wherein the OFDM signal comprises a plurality of symbols each having a plurality of subcarriers.

17. The memory medium of claim 16,

wherein said generating the plurality of packets with the amount of training information depending on the time of day comprises varying the ratio of training subcarriers to data subcarriers in the OFDM signal.

18. The memory medium of claim 15,

wherein each of the plurality of possible training patterns specifies a different amount of training information.

19. The memory medium of claim 15,

wherein each of the plurality of possible training patterns specifies a different subset of a plurality of subcarriers of the signal modulated in the frequency domain as training subcarriers.

20. The memory medium of claim 15,

wherein the content comprises audiovisual content,

wherein the plurality of packets are configured to be transmitted to the one or more receivers in a wireless manner using a frequency domain modulated signal according to a digital television broadcasting standard.