A method and system is presented for coordinating the transmission of supplemental digital data to accompany broadcast data, and in particular, analog radio broadcasts, among a plurality of broadcasters. The supplemental digital data may provide information about the particular broadcast data being transmitted (i.e. cut data) or may be supplemental to such data (i.e. news, weather and traffic data). The supplemental digital data to be presented is sorted based on particular algorithms which may take into account broadcaster-specified criteria such as target audience, time of day, type of broadcast data presented, and the like. The supplemental digital data may be audio data, visual data, or audio-visual data for presentation with the broadcast data. The supplemental digital data may further be advertisement data. The advertisement data may be sold by the broadcasters or the party coordinating the IBOC transmission of the supplemental digital data. The supplemental digital data may play simultaneously with muted broadcast data or at a user-specified time.

The present invention provides systems and methods that enable the delivery of rich digital content over terrestrial base frequency modulated broadcast systems. The digitally rich content may include, but not limited to live or recorded video, command and control information. Access to the content may be on a free, pay-per-use, pay-per-view, or pay-per-broadcast or multicast method.

Systems and methods for increasing transmission bandwidth efficiency by the analysis and synthesis of the ultimate components of transmitted content are presented. To implement such a system, a dictionary or database of elemental codewords can be generated from a set of audio clips. Using such a database, a given arbitrary song or other audio file can be expressed as a series of such codewords, where each given codeword in the series is a compressed audio packet that can be used as is, or, for example, can be tagged to be modified to better match the corresponding portion of the original audio file. Each codeword in the database has an index number or unique identifier. For a relatively small number of bits used in a unique ID, e.g. 27-30, several hundreds of millions of codewords can be uniquely identified. By providing the database of codewords to receivers of a broadcast or content delivery system in advance, instead of broadcasting or streaming the actual compressed audio signal, all that need be transmitted is the series of identifiers along with any modification instructions to the identified codewords. After reception, intelligence on the receiver having access to a locally stored copy of the dictionary can reconstruct the original audio clip by accessing the codewords via the received IDs, modify them as instructed by the modification instructions, further modify the codewords either individually or in groups using the audio profile of the original audio file (also sent by the encoder) and play back a generated sequence of phase corrected codewords and modified codewords as instructed. In exemplary embodiments of the present invention, such modification can extend into neighboring codewords, and can utilize either or both (i) cross correlation based time alignment and (ii) phase continuity between harmonics, to achieve higher fidelity to the original audio clip.

A method for processing a digital audio broadcast signal in a radio receiver includes: receiving a digital audio broadcast signal; demodulating the digital audio broadcast signal to produce an analog audio stream and a digital audio stream; determining a digital signal quality value for the digital audio stream; blending an output of the radio receiver from the analog audio stream to the digital audio stream when the digital signal quality value exceeds an adaptive analog-to-digital threshold value; and blending the output of the radio receiver from the digital audio stream to the analog audio stream when the digital signal quality value falls below an adaptive digital-to-analog threshold value, wherein the adaptive digital-to-analog threshold value is lower than the adaptive analog-to-digital threshold value.

A switching module transmits channel content to a transport encoder. The switching module receives notification content associated with an emergency action system (EAS) message, and transmits the notification content to the transport encoder in place of the channel content.

A method for processing audio signals in a radio transmitter, includes: receiving an analog audio sample stream and a digital audio sample stream; determining offsets in time between the analog audio stream and the digital audio stream using a normalized cross-correlation of audio envelopes of the analog audio sample stream and the digital audio sample stream; filtering the determined offsets in time to produce filtered offset values; determining an alignment slip adjustment value as a function of the filtered offset values; aligning the analog audio sample stream and the digital audio sample stream using the determined alignment slip adjustment value; and generating a hybrid radio signal for broadcast that includes time-aligned analog audio and digital audio.

According to an aspect of the present invention, there is provided a method for providing additional bandwidth to receivers that can decode a higher modulation comprising trading a peak-to-average power ratio (PAPR) reduction induced constellation noise of all or a subset of in-band on-channel (I BOC) carriers within an orthogonal frequency division multiplexing (ODFM) waveform with data carrying superposition modulation.

A method for processing a digital audio broadcast signal includes: separating an analog audio portion and a digital audio portion of the digital audio broadcast signal; determining the loudness of the analog audio portion and the digital audio portion over a first short time interval; using the loudness of the analog and digital audio portions to calculate a short term average gain; determining a long term average gain; converting one of the long term average gain or the short term average gain to dB; if an output has been blended to digital, adjusting a digital gain parameter by a preselected increment to produce a digital gain parameter; if an output has not been blended to digital, setting the digital gain parameter to the short term average gain; providing the digital gain parameter to an audio processor; and repeating the above steps using a second short time interval.

An importer-exporter includes at least a first interface that receives channel packets and a stream of emergency action signal (EAS) packets. The channel packets include channel content for multiple media channels, and the stream of EAS packets include first EAS notification content from a first EAS encoder. The first EAS notification content is associated with one or more particular media channels. A processor and associated memory are configured to implement a switching module that includes a login module and a multiplexer. The login module monitors the stream of EAS packets, and selects either channel content or first notification content for inclusion in broadcasts of each of the media channels based on the monitored stream of EAS packets. Thea multiplexer transmits the content selected by the login module for inclusion in the broadcasts of each of the plurality of media channels.

According to an aspect of the present invention, there is provided a method for providing additional bandwidth to receivers that can decode a higher modulation comprising trading a peak-to-average power ratio (PAPR) reduction induced constellation noise of all or a subset of in-band on-channel (IBOC) carriers within an orthogonal frequency division multiplexing (ODFM) waveform with data carrying superposition modulation.