Patent EA-002178-B1 (EA)
Title: Signalling protocol for satellite direct radio broadcast system
Inventor: CAMPANELLA S JOSEPH
IPC: H04H40/90
Filed: 1998-11-06
Abstract: 1. A method of formatting a signal for broadcast transmission to remote receivers comprising the steps of: receiving a service comprising at least a first service component selected from the group consisting of audio, data, static images, dynamic images, paging signals, text, messages and panographic symbols; and generating a broadcast channel bit stream frame by appending a service control header to said service to dynamically control reception of said service at said remote receivers, said service control header comprising service control data; wherein said service comprises an overall bit rate of K bits per second, said overall bit rate corresponding to n multiples of a minimum bit rate of L bits per second, said frame period being M seconds, said service having n x L x M = n x P bits per frame, said frame comprising n x P bits for said service and n x Q bits for said service control header, wherein K, n, L, M, P and Q are numerical values, respectively providing said service control header with first service component control data for dynamically controlling the reception of said first service component at said remote receivers and providing said service control header with second service component control data for dynamically controlling reception of said second service component at said remote receivers. 2. A method as claimed in claim 1, wherein at least one of said first service component control data and said second service component control data comprises at least one of a plurality of fields comprising a service component length field, a service component type field, an encryption field, a program type field and a language field, wherein  said service component length field indicates the bit rate of the corresponding one of said first service component and said second service component, said service component type field indicates which of a plurality of signals is contained in the corresponding one of said first service component and said second service component, said encryption field indicates which of a plurality of encryption methods is used to encrypt the corresponding one of said first service component and said second service component, said program type field indicates which of a plurality of programs is transmitted via the corresponding one of said first service component and said second service component, and said language field indicates in which of a plurality of languages the corresponding one of said first service component and said second service component is generated. 3. A method as claimed in claim 2, further comprising the step of providing said service component length field with n bits to indicate said bit rate of the corresponding one of said first service component and said second service component, said bit rate being a multiple number of m bits per second, wherein 1 ( said multiple number ( 2<n>, m bits per second is a minimum bit rate, n and m are numerical values, and the contents of said service component length field is a binary number having a decimal value between 0 and 2<n> corresponding to said multiple number. 4 A method as claimed in claim 3, further comprising the steps of: receiving said frame at said remote receivers; and demultiplexing the corresponding one of said first service component and said second service component from said frame using said service component length field. 5. A method as claimed in claim 3, wherein n = 4' bits and m = 8000 bits per second. 6. A method as claimed in claim 2, further comprising the step of providing said service component type field with one of a plurality of values corresponding to respective ones of said plurality of signals, said plurality of signals comprising Motion Pictures Expert Group (MPEG) coded audio, general data having no specified format, Joint Photographic Expert Group (JPEG) coded picture data, video and invalid data. 7. A method as claimed in claim 2, further comprising the step of providing said encryption field with a first value and a second value when the corresponding one of said first service component and said second service component is encrypted and is not encrypted, respectively. 8. A method as claimed in claim 2, further comprising the step of providing said program type field with one a plurality of values corresponding to respective ones of said plurality of programs, said plurality of programs comprising music, a talk radio show, video, text, a censored program, an advertisement, and a program directed to a selected topic. 9. A method as claimed in claim 2, further comprising the step of providing said language field with one of a plurality of values corresponding to respective ones of said plurality of languages. 10. A method as claimed in claim 1, wherein said service comprises a second service component, and further comprising the steps of: dividing at least a portion of said frame into data fields; and interleaving at least part of said first service component and said second service component into each of said data fields. 11. A method as claimed in claim 10, wherein said first service component and said second service component have a bit rate of multiples of L/2 bits per second, said interleaving step comprising the step of adding padding bits to each data field when the number of said multiples of L/2 bits per second is an odd number. 12. A signal comprising broadcast information embodied in a carrier wave for broadcast transmission to remote receivers, said signal comprising a broadcast channel bit stream frame generated by appending a service control header to a service, said service comprising at least one service component selected from the group consisting of audio, data, static images, dynamic images, paging signals, text, messages and panographic symbols, said service control header comprising service control data for dynamically controlling reception of said service at said remote receivers, said service comprising an overall bit rate of K bits per second, said overall bit rate corresponding to n multiples of a minimum bit rate of L bits per second, said frame period being M seconds, said service having n x L x M = n x P bits per frame, said frame comprising n x P bits for said service and n x Q bits for said service control header, wherein K, n, L, M, P and Q are numerical values, respectively. 13. A signal as claimed in claim 12, wherein said overall bit rate K for said service is between 16 kilobits per second and 128 kilobits per second, said minimum bit rate L for said service is 16 kilobits per second, n is an integer  1 <= n <= 8, said frame period M is 432 milliseconds, P is 6912 and Q is 224, said frame comprising n x 6912 bits for said service and n x 224 bits for said service control header and n x 7136 total bits. 14. A signal as claimed in claim 13, wherein said service comprises a first service component and a second service component, at least a portion of said frame being divided into 432 data fields which are approximately 1 millisecond in duration, each of said data fields having n x 16 bits, said first service component and said second service component being interleaved into each of said data fields. 15. A method of formatting a signal for broadcast transmission to remote receivers comprising the steps of: receiving a service comprising at least a first service component selected from the group consisting of digitized audio signals, analog audio signals and analog signals; digitizing said first service component if said first service component is analog; and compressing said first service component using source coding selected from a group of coding schemes consisting of Motion Pictures Expert Group (MPEG) 1, wherein said compressing step comprises the step of sampling said first service component at a sampling frequency which is synchronized to the bit rate of said first service component, and  generating a broadcast channel bit stream frame by appending a service control header to said service to dynamically control reception of said service at said remote receivers, said service control header comprising service control data for dynamically controlling the reception of said first service component and said second service component at said remote receivers. 16. A method as claimed in claim 15, further comprising the step of synchronizing the framing operations of an MPEG encoder with said service control header, said broadcast channel bit stream frame being operable to transmit an MPEG frame generated by said MPEG encoder as a subframe thereof. 17. A method as claimed in claim 20, wherein said synchronizing step comprises the step of aligning the first bit in said first service component with the first bit of a frame header generated by said MPEG encoder. 18. A signal comprising broadcast information embodied in a carrier wave for broadcast transmission to remote receivers, said signal comprising a broadcast channel bit stream frame generated by appending a service control header to a service, said service having at least one service component selected from the group consisting of digitized audio signals, analog audio signals and analog signals, said service component being digitized if said service component is analog and compressed using source coding selected from a group of coding schemes consisting of Motion Pictures Expert Group (MPEG) coding, MPEG 1, MPEG 2, MPEG 2.5 and MPEG 2.5, layer 3, said service control header comprising service control data for dynamically controlling reception of said service at said remote receivers, said source coding having framing operations which are synchronized with said service control header, said broadcast channel bit stream frame being operable to transmit an MPEG coding frame generated via said source coding as a subframe thereof. 19. A method of formatting a signal for broadcast transmission to remote receivers comprising the steps of: receiving a service comprising at least a first service component selected