摘要:
System for providing hierarchical services in a data network. A method is provided for inserting content into a content stream for rendering on a device. The method includes obtaining one or more annotation parameters that comprise a content identifier, and determining an insertion point indicator that indicates a location in the content stream. The method also includes retrieving the content based on the content identifier, and inserting the content in the content stream at a location indicated by the insertion point indicator.
摘要:
Techniques to seamlessly switch reception between multimedia programs are described. For “continued decoding”, a wireless device continues to receive, decode, decompress, and (optionally) display a current program, even after a new program has been selected, until overhead information needed to decode the new program is received. After receiving the overhead information, the wireless device decodes the new program but continues to decompress the current program. The wireless device decompresses the new program after decoding this program. For “early decoding”, the wireless device receives a user input and identifies a program with potential for user selection. The identified program may be the one highlighted by the user input or a program anticipated to be selected based on the user input. The wireless device initiates decoding of the identified program, prior to its selection, so that the program can be decompressed and displayed earlier if it is subsequently selected.
摘要:
Techniques for transmitting overhead information to facilitate efficient reception of individual data streams are described. A base station may transmit multiple data streams on multiple data channels (or MLCs). The MLCs may be transmitted at different times and on different frequency subbands. The time-frequency location of each MLC may change over time. The overhead information indicates the time-frequency location of each MLC and may be sent as “composite” and “embedded” overhead information. The composite overhead information indicates the time-frequency locations of all MLCs and is sent periodically in each super-frame. A wireless device receives the composite overhead information, determines the time-frequency location of each MLC of interest, and receives each MLC at the indicated time-frequency location. The embedded overhead information for each MLC indicates the time-frequency location of that MLC in the next super-frame and is transmitted along with the payload of the MLC in the current super-frame.
摘要:
A wireless communication apparatus in a hierarchically coded modulation system can use error control mechanisms generated during decoding of base layer information to predict a probability of successful demodulation of enhancement layer information. Performance in the demodulation of the base layer correlates to performance in the demodulation of the enhancement layer. The receiver can determine whether to attempt demodulation of temporally correlated enhancement layer data based in part on the predicted probability of success. If the receiver determines not to demodulate the enhancement layer, the receiver can power down the enhancement layer demodulator, or otherwise minimize the power expended in the enhancement layer demodulator.
摘要:
Techniques to seamlessly switch reception between multimedia programs are described. For “continued decoding”, a wireless device continues to receive, decode, decompress, and (optionally) display a current program, even after a new program has been selected, until overhead information needed to decode the new program is received. After receiving the overhead information, the wireless device decodes the new program but continues to decompress the current program. The wireless device decompresses the new program after decoding this program. For “early decoding”, the wireless device receives a user input and identifies a program with potential for user selection. The identified program may be the one highlighted by the user input or a program anticipated to be selected based on the user input. The wireless device initiates decoding of the identified program, prior to its selection, so that the program can be decompressed and displayed earlier if it is subsequently selected.
摘要:
Conserving power for coded transmissions comprises ceasing to process parity packets once associated data packets are deemed correct or corrected. Once data packets are deemed correct or corrected, the receiving unit can shut off during the transmission of parity packets.
摘要:
Techniques for multiplexing multiple data streams using frequency division multiplexing (FDM) in an OFDM system are described. M disjoint “interlaces” are formed with U usable subbands. Each interlace is a different set of S subbands, where U=M·S. The subbands for each interlace are interlaced with the subbands for each of the other M−1 interlaces. M slots may be defined for each symbol period and assigned slot indices 1 through M. The slot indices may be mapped to interlaces such that (1) frequency diversity is achieved for each slot index and (2) the interlaces used for pilot transmission have varying distances to the interlaces used for each slot index, which improves channel estimation performance. Each data stream may be processed as data packets of a fixed size, and different numbers of slots may be used for each data packet depending on the coding and modulation scheme used for the data packet.
摘要:
To broadcast different types of transmission having different tiers of coverage in a wireless broadcast network, each base station processes data for a wide-area transmission in accordance with a first mode (or coding and modulation scheme) to generate data symbols for the wide-area transmission and processes data for a local transmission in accordance with a second mode to generate data symbols for the local transmission. The first and second modes are selected based on the desired coverage for wide-area and local transmissions, respectively. The base station also generates pilots and overhead information for local and wide-area transmissions. The data, pilots, and overhead information for local and wide-area transmissions are multiplexed onto their transmission spans, which may be different sets of frequency subbands, different time segments, or different groups of subbands in different time segments. More than two different types of transmission may also be multiplexed and broadcast.
摘要:
Techniques for multiplexing and transmitting multiple data streams are described. Transmission of the multiple data streams occurs in “super-frames”. Each super-frame has a predetermined time duration and is further divided into multiple (e.g., four) frames. Each data block for each data stream is outer encoded to generate a corresponding code block. Each code block is partitioned into multiple subblocks, and each data packet in each code block is inner encoded and modulated to generate modulation symbols for the packet. The multiple subblocks for each code block are transmitted in the multiple frames of the same super-frame, one subblock per frame. Each data stream is allocated a number of transmission units in each super-frame and is assigned specific transmission units to achieve efficient packing. A wireless device can select and receive individual data streams.
摘要:
Methods and apparatus for providing power efficient time management for mobile media. In an aspect, a method is provided that operates to provide time management for mobile media that is distributed over a network. The method includes receiving the mobile media comprising source video frames that are associated with a source time reference, and capturing a portion of the source video frames. The method also includes re-labeling the portion of the source video frames based on a system time reference to produce synchronized video frames, wherein the network provides communications based on the system time reference, and assembling a transmission frame that comprises the synchronized video frames.