Abstract: Methods and circuits for positioning a signal sampling window within a wireless receiver device for use in a multi-transmitter wireless broadcast network include generating a long channel model based upon a signal identifying transmitters that can be processed without aliases, and positioning the signal sampling window based upon the long channel model. For example, in a MediaFLO® broadcast, the long channel model may be generated by receiving positioning pilot channel (PPC) signals. Positions for the signal sampling window may be determined by identifying hypothetical signal sampling window positions, calculating signal to interference and noise ratio (SINR) values for each identified hypothetical, and selecting the hypothetical with the best SINR. Using a long channel model to position the signal sampling window may provide improved window placement, reduce destructive aliasing, and reduce a time guard in the window placement. The long channel model may be used in conjunction with terrain databases.

Abstract: This application relates to systems and methods for recovering data in multimedia file segments. A communication device may receive a multimedia file segment that includes damaged data. The communication device may replace the damaged data with dummy data to reconstruct the multimedia file segment. The communication device may then play the reconstructed multimedia file segment. Thus, by replacing the damaged data with dummy data, the communication device may play a multimedia file segment even when part of the segment may be damaged.

Abstract: 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.

Abstract: Receiver devices may receive broadcast content and decode data on multiple carriers in time division mode, and change carriers to receive data from different radio frequencies. Embodiments include methods, systems and devices that enable scheduling content for broadcast by two or more mobile TV broadcasters so that non-exclusive real time content broadcasts in one radio frequency band does not overlap with non-real time content broadcast in another radio frequency band, enabling simultaneous reception of non-real time broadcast by one network and non-exclusive real time content broadcast by another network. Receiver devices may simultaneously receive non-real time content on two or more radio frequency bands and real time content on any of the radio frequency bands.

Abstract: A system for transmitting a data stream, includes a transmitter for broadcasting a radio frequency communication signal comprising at least one superframe having at least a first data stream encoded therein, and overhead information carried in the superframe, the overhead information comprising a control channel, the control channel having control channel information for separating the at least one first data stream from any other data streams encoded in the at least one superframe. A system for receiving data includes a receiver configured to receive a radio frequency communication signal comprising at least one superframe having at least a first data stream encoded therein; and overhead information carried in the superframe, the overhead information comprising a control channel, the control channel having control channel information for separating the at least one first data stream from any other data streams encoded in the at least one superframe.

Abstract: Methods and circuits for positioning a signal sampling window within a wireless receiver device for use in a multi-transmitter wireless broadcast network include generating a long channel model based upon a signal identifying transmitters that can be processed without aliases, and positioning the signal sampling window based upon the long channel model. For example, in a MediaFLO® broadcast, the long channel model may be generated by receiving positioning pilot channel (PPC) signals. Positions for the signal sampling window may be determined by identifying hypothetical signal sampling window positions, calculating signal to interference and noise ratio (SINR) values for each identified hypothetical, and selecting the hypothetical with the best SINR. Using a long channel model to position the signal sampling window may provide improved window placement, reduce destructive aliasing, and reduce a time guard in the window placement. The long channel model may be used in conjunction with terrain databases.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media for encoding data for transmission on a communication link of a content delivery system includes: receiving data to be communicated to a device, the data received as a multiple data link layer packets of a logical channel carrying broadcast data; encoding the multiple data link layer packets of the logical channel as one outer codeword using an outer code at an outer code rate; encoding symbols of the outer codeword with an inner code; and indicating the outer code and the outer code rate through signaling, including setting a first value for a first field of a control channel and setting a second value for a second field of the control channel, wherein the first value is determined by the outer code, and the second value is determined by the outer code rate.

Abstract: Methods, systems and apparatus, including computer programs encoded on computer storage media, for operating time division multiplexing (TDM) on segments of MediaFLO superframes comprising: generating a MediaFLO OFDM waveform with at least one MediaFLO frame; allocating a MediaFLO local multiplex time segment in the at least one MediaFLO frame for non-MediaFLO data; and inserting the non-MediaFLO data into the MediaFLO local multiplex time segment. In one example, the non-MediaFLO data is a DVB-H table that is split into two time segments within the MediaFLO OFDM waveform. In another aspect, the apparatus and method for operating time division multiplexing (TDM) on alternate whole superframes of time comprising generating a MediaFLO OFDM waveform with a plurality of MediaFLO superframes; multiplexing the MediaFLO OFDM waveform with non-MediaFLO data over the plurality of MediaFLO superframes for whole superframe durations; and inserting MediaFLO data in at least one of the plurality of MediaFLO superframes.

Abstract: Alignment of an antenna and a polarizer for the antenna are automatically adjusted and the frequency setting of a frequency-tunable receiver is automatically adjusted while receiving a broadcast communication signal that is forward-error-correction coded by processing the forward-error-correction code of the received signal to measure a channel-bit-error-rate-affected parameter for the received signal; by realigning the antenna and the polarizer from their respective initial positions in response to the measured parameter until the measured parameter is minimized; and by retuning the receiver from its initial frequency setting in response to the measured parameter until the measured parameter is minimized.

Abstract: A satellite identification system for identifying a communications satellite from which a broadcast communication signal is being received by an antenna, wherein the communication signal includes data identifying a programmer that broadcast the communication signal and/or an uplink location from which the communication signal is broadcast. The system includes a memory storing a look-up table correlating satellite identification data for a plurality of satellites with the programmer identification data and/or the uplink location data for the plurality of satellites; means for detecting the programmer identification data and/or the uplink location data from a communication signal received by the antenna from one of the plurality of satellites; and means for accessing the look-up table in response to the detected programmer identification data and/or the uplink location data to retrieve the satellite identification data for the satellite from which the communication signal is received.

Abstract: Alignment of an antenna and a polarizer for the antenna are automatically adjusted and the frequency setting of a frequency-tunable receiver is automatically adjusted while receiving a broadcast communication signal that is forward-error-correction coded by processing the forward-error-correction code of the received signal to measure a channel-bit-error-rate-affected parameter for the received signal; by realigning the antenna and the polarizer from their respective initial positions in response to the measured parameter until the measured parameter is minimized; and by retuning the receiver from its initial frequency setting in response to the measured parameter unitl the measured parameter is minimized.

Abstract: A video scrambling system scrambles adjacent sequentially odd and even video information lines of a video frame by simultaneously storing in a memory a pair of such adjacent lines; and forming a pair of scrambled video information lines by retrieving from the memory a segment of one of the stored video information lines followed by a segment of the other stored video information line, and by shifting the phase of one of the retrieved segments of the scrambled video information line in relation to the other retrieved segment of said scrambled video information line by an odd multiple of one-half the phase of the chrominance information cycle. This phase shift causes the phase relationship of all segments with respect to the color reference signal to be the same; and as a result there is no differential hue shift in the descrambled signal. In a complementary descrambling system, the two retrieved segments of each descrambled video information line are retrieved consecutively without an intervening phase shift.

Abstract: A receiver interface system for enabling an operator to access different types of services in a like manner, wherein the services contain different combinations of service components received by a receiver in different portions of one or more different frequency channels, such as television channels. The system includes a plurality of separate interface channels for carrying different types of services containing different combinations of the service components; switching means for selecting a said service, wherein the switching means is coupled to the interface channels for accessing the respective interface channels in a like manner; and a decoder coupled to the receiver and the interface channels for accessing the components of said selected service received by the receiver in different portions of one or more different frequency channels to provide said selected service on the interface channel carrying the selected service.

Abstract: A system for companding digital audio signal samples processes the digital audio signal samples to correct errors induced by the compression and expansion processes. These errors are calculated prior to compressing the samples. Such errors are calculated in accordance with a predetermined compression process and a predetermined expansion process; and the digital audio signal samples are corrected in accordance with such calculations prior to compression. The compression process includes providing a 3-bit gain word for a block of 70 samples. The gain word is computed in accordance with the position of the most significant "1" bit in the sample(s) having the peak magnitude. Each individual sample is processed in accordance with the block gain word to compress the sample by reducing the number of magnitude bits.

Abstract: In a system for scrambling an audio signal for transmission with a video signal having non-video information intervals, an analog audio signal is converted into a scrambled compressed digital audio signal; individual bits from the scrambled compressed digital audio signal are combined to provide 2-bit digital words; each digital word is converted into an 8-bit digital PAM data signal having a binary value bearing a predetermined relationship to the binary value of the converted 2-bit digital word; the 8-bit digital PAM data signal is converted into a 4-level PAM analog signal; and the PAM analog signals are inserted into the non-video information intervals of the video signal for transmission. A descrambling system descrambles the 4-level PAM analog signals by a complementary scheme.

Abstract: A system for scrambling a video signal having a plurality of horizontal lines, each of which includes a video information portion and a non-video information portion. The scrambling system includes a memory; means for storing the video information portion of each video signal line in the memory; and means for forming scrambled horizontal lines by retrieving each of a plurality of said stored video information lines in a plurality of segments preceded by a non-video segment and separated by non-video segment(s). The retrieval means include means for varying the respective durations of the retrieved video information segments in individual scrambled horizontal lines in accordance with an encryption keystream; and means for varying the total duration of the non-video segments for individual scrambled horizontal lines in accordance with a predetermined timing pattern. A complementary descrambling system also is disclosed.

Abstract: In the scrambling system, an analog audio signal is converted into a digital signal to provide a sequence of digital signal samples corresponding to the analog audio signal. Each digital signal sample is compressed to provide compressed signal samples having a sign bit, three exponent bits and seven mantissa bits. Each bit of each compressed signal sample is exclusive-OR'd with a unique keystream to thereby scramble the audio signal. A Hamming code generator generates code bits for correcting singular errors in a combination of the sign bit, the exponent bits and the code bits; and a parity bit generator generates a parity bit for detecting double errors in a combination of the sign bit, the exponent bits and the code bits and for further detecting an error in the most significant mantissa bit and/or the parity bit.