MULTIDIVERSITY HANDOFF IN A WIRELESS BROADCAST SYSTEM

• US 20080170490A1
• Filed: 01/12/2007
• Published: 07/17/2008
• Est. Priority Date: 01/12/2007
• Status: Active Grant

• Current Assignee: Monument Bank of Intellectual Property, LLC (Dominion Harbor Enterprises, LLC)
• Original Assignee: Wi-LAN Inc.
• Inventors: Madan, Seema, Govind, Keerthi S., Petry, Brian D., Marsh, Gene W., Burchill, William S., Gummadi, Srikanth, Connors, Dennis P.
• Granted Patent: US 8,774,229 B2
• Time in Patent Office: Days
• US Class Current: 370/203
• CPC Class Codes: H04L 27/2647 Arrangements specific to the receiver only equalisation H04L27/01
• CPC Class Codes: H04L 5/023 Multiplexing of multicarrier modulation signals multicarrier modulation H04L27/2601
• CPC Class Codes: H04N 21/235 Processing of additional data, e.g. scrambling of additional data or processing content descriptors
• CPC Class Codes: H04N 21/2362 Generation or processing of Service Information [SI]
• 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 21/242 Synchronization processes, e.g. processing of PCR [Program Clock References] arrangements for synchronising broadcast or distribution via plural systems in broadcast distribution systems H04H20/18
• CPC Class Codes: H04N 21/26208 the scheduling operation being performed under constraints
• CPC Class Codes: H04N 21/6131 involving transmission via a mobile phone network wireless downlink channel access H04W74/006
• CPC Class Codes: H04N 21/64315 DVB-H

Abstract

A wireless broadcast system that collects content for distribution over a wireless communication network. The content stream is encapsulated into a stream of transport packets for broadcast over the wireless communication link. The stream of transport packets are simultaneously broadcast as part of an identical signal from a plurality of synchronized transmitters in a single frequency network. A receiver acquires the broadcast signal and synchronizes to the signal. Once the receiver is synchronized to one of the transmitters in the single frequency network, the receiver can receive signals from any, or multiple, of the transmitters in the network without re-synchronizing.

Claims

1. A method of maintaining signal reception in a wireless broadcast network, the method comprising:

receiving an identical orthogonal frequency division multiplexed (OFDM) signal from a first transmitter of a plurality of transmitters in the wireless broadcast network, the plurality of transmitters configured to simultaneously transmit the identical OFDM signal;

synchronizing to the identical OFDM signal; and

receiving the identical OFDM signal from a second transmitter of the plurality of transmitters while maintaining synchronization with the identical OFDM signal.

2. The method of claim 1, wherein the wireless broadcast network is a single frequency network and the plurality of transmitters are synchronized with respect to each other.

3. The method of claim 1, wherein the identical OFDM signal comprises a plurality of individual content data streams that are combined into an aggregate data stream.

4. The method of claim 3, wherein the identical OFDM signal includes one connection identification value associated with the entire aggregate data stream.

5. The method of claim 3, wherein the identical OFDM signal includes a unique connection identification value associated with each individual content data stream in the aggregate data stream.

6. The method of claim 3, wherein the plurality of individual content streams comprise IP content.

7. The method of claim 1, further comprising simultaneously receiving the identical OFDM signal from a plurality of transmitters and maintaining synchronization with the identical OFDM signal.

8. The method of claim 1, wherein the identical OFDM signal is simultaneously received from both the first transmitter and the second transmitter for a time period and, at the expiration of the time period, the identical OFDM signal is received from only the second transmitter while synchronization to the identical OFDM signal is maintained.

9. A receiver comprising:

a receiving module adapted to receive orthogonal frequency division multiplexed (OFDM) signals from a plurality of transmitters in a wireless broadcast network, the plurality of transmitters configured to simultaneously transmit an identical OFDM signal; and

a processor configured to synchronize to the identical OFDM signal received by the receiving module from a first transmitter of the plurality of transmitters, and to maintain synchronization with the identical OFDM signal while the receiving module receives the identical OFDM signal from a second transmitter of the plurality of transmitters.

10. The receiver of claim 9, wherein the identical OFDM signal comprises an aggregate content stream comprised of a plurality of individual content streams.

11. The receiver of claim 10, wherein the identical OFDM signal includes at least one connection identification value.

12. The receiver of claim 11, wherein only one connection identification value is associated with the aggregate content stream.

13. The receiver of claim 11, wherein a unique connection identification value is associated with each of the individual content streams in the aggregate content stream.

14. The receiver of claim 9, wherein the identical OFDM signal includes a base station identification.

15. The receiver of claim 9, wherein the receiver module simultaneously receives the identical OFDM signal from a plurality of transmitters while synchronization with the identical OFDM signal is maintained.

16. The receiver of claim 9, wherein the identical OFDM signal is simultaneously received by the receiver module from both the first transmitter and the second transmitter for a time period and, at the expiration of the time period, the identical OFDM signal is received by the receiver module from only the second transmitter while synchronization to the identical OFDM signal is maintained.

17. The receiver of claim 9, wherein the wireless broadcast network is a single frequency network and the plurality of transmitters are synchronized with respect to each other

18. A network comprising:

a single frequency network adapter configured to receive encapsulated transport stream packets and to format the transport stream packets into service data units;

a plurality of transmitters configured to receive the service data units and to synchronously transmit the service data units such that each of the plurality of transmitters broadcasts an identical signal; and

at least one receiver configured to synchronize to the identical signal received from a first transmitter of the plurality of transmitters, and to receive the identical signal from a second transmitter of the plurality of transmitters while maintaining synchronization with the identical signal.

19. The network of claim 18, wherein the signal received is an orthogonal frequency division multiplexed (OFDM) signal.

20. A method of broadcasting comprising:

receiving encapsulated transport stream packets and formatting the transport stream packets into service data units;

synchronously transmitting the service data units from a plurality of transmitters such that each of the plurality of transmitters simultaneously broadcasts an identical signal;

receiving the identical signal from a first transmitter of the plurality of transmitters;

synchronizing to the identical signal received from the first transmitter; and

receiving the identical signal from a second first transmitter of the plurality of transmitters while maintaining synchronization with the identical signal.

21. The network of claim 20, wherein the identical signal comprises an orthogonal frequency division multiplexed (OFDM) signal.

22. One or more computer readable media storing computer executable instructions that, when executed perform a method comprising:

receiving an identical orthogonal frequency division multiplexed (OFDM) signal from a first transmitter of a plurality of transmitters in a wireless broadcast network, the plurality of transmitters configured to simultaneously transmit the identical OFDM signal;

synchronizing to the identical OFDM signal; and

receiving the identical OFDM signal from a second transmitter of the plurality of transmitters while maintaining synchronization with the identical OFDM signal.