Patent EA-001540-B1 (EA)
Title: Real-time information delivery system for aircraft
Inventor: SACHDEV DHARMENDRA KUMAR
IPC: H04B7/185
Filed: 1997-11-06
Abstract: 1. A system for providing real-time broadcast programs to aircraft passengers, comprising: at least one terrestrial broadcast station for transmitting a plurality of different low-bandwidth broadcast programs and at least one high-bandwidth broadcast program; at least one relay satellite for receiving and retransmitting said low-bandwidth broadcast programs and said at least one high-bandwidth broadcast program, said retransmission occurring on at least one downlink signal in which different ones of said low-bandwidth broadcast programs are transmitted on different time-division multiplex (TDM) channels at the same carrier frequency of less than about 3000 MHz; and a broadcast receiver carried on board an aircraft, said broadcast receiver including at least one demodulator for demodulating said at least one downlink signal and a demultiplexer coupled to said demodulator for demultiplexing said TDM channels to reproduce said plurality of low-bandwidth broadcast programs, said broadcast receiver being coupled to an on-board passenger entertainment system for providing said low-bandwidth broadcast programs and said at least one high-bandwidth broadcast program to passengers on board said aircraft. 2. A system as claimed in claim 1, wherein said at least one downlink signal contains an encrypted broadcast program, and wherein said broadcast receiver is adapted to decrypt said encrypted broadcast program. 3. A system as claimed in claim 1, wherein said at least one downlink signal comprises a spot beam which includes at least a portion of the flight path of said aircraft. 4. A system as claimed in claim 1, wherein said at least one downlink signal comprises a plurality of contiguous spot beams which collectively include at least a portion of the flight path of said aircraft, and wherein at least one of said broadcast programs is transmitted in more than one of said spot beams. 5. A system as claimed in claim 4, wherein said plural contiguous spot beams have different carrier frequencies, and wherein said broadcast receiver is switchable between or among said carrier frequencies. 6. A system as claimed in claim 1, wherein said carrier frequency is in the range of 1100 MHz to 2000 MHz. 7. An on-board system for providing a plurality of low-bandwidth broadcast programs and at least one high-bandwidth broadcast program to aircraft passengers, said low-bandwidth broadcast programs and said at least one high-bandwidth broadcast program being transmitted from at least one satellite on at least one downlink signal in which different ones of said low-bandwidth broadcast programs are transmitted on different time-division multiplex (TDM) channels at the same carrier frequency of less than about 3000 MHz, said on-board system comprising: a satellite antenna carried by said aircraft for receiving said at least one downlink signal; at least one demodulator coupled to said antenna for demodulating said at least one downlink signal; a demultiplexer coupled to said demodulator for demultiplexing said TDM channels to reproduce said plurality of low-bandwidth broadcast programs; and a passenger entertainment system coupled to at least one of said demodulator and said demultiplexer for providing said low-bandwidth broadcast programs and said at least one high-bandwidth broadcast program to passengers on board said aircraft. 8. An on-board system as claimed in claim 7, wherein said at least one downlink signal contains an encrypted broadcast program, and wherein said on-board system is adapted to decrypt said encrypted broadcast program. 9. An on-board system as claimed in claim 7, wherein said on-board system is switchable between at least two different carrier frequencies. 10. An on-board system as claimed in claim 7, wherein said carrier frequency is in the range of 1100 MHz to 2000 MHz. 11. A method for providing real-time broadcast programs to aircraft passengers, comprising: transmitting a plurality of different low-bandwidth broadcast programs and at least one high-bandwidth broadcast program from at least one terrestrial broadcast station to a relay satellite; retransmitting said broadcast programs from said relay satellite to an aircraft in flight, said retransmission occurring on at least one downlink signal in which different ones of said low-bandwidth broadcast programs are transmitted on different time-division multiplex (TDM) channels at the same carrier frequency of less than about 3000 MHz; and receiving said downlink signal on board said aircraft and demultiplexing said TDM channels to reproduce said plurality of low-bandwidth broadcast programs and said at least one high-bandwidth broadcast program. 12. A method as claimed in claim 11, wherein said at least one downlink signal contains an encrypted broadcast program, and wherein said method further comprises the step of decrypting said encrypted broadcast program. 13. A method as claimed in claim 11, wherein said at least one downlink signal comprises a spot beam which includes at least a portion of the flight path of said aircraft. 14. A method as claimed in claim 11, wherein said at least one downlink signal comprises a plurality of contiguous spot beams which collectively include at least a portion of the flight path of said aircraft, and further comprising the step of transmitting at least one of said broadcast programs in more than one of said spot beams. 15. A method as claimed in claim 11, wherein said at least one downlink signal comprises a plurality of contiguous spot beams having different carrier frequencies, said contiguous spot beams collectively including at least a portion of the flight path of said aircraft, and wherein the step of receiving said downlink signal on board said aircraft comprises receiving different ones of said carrier frequencies at different times. 16. A method as claimed in claim 11, wherein said carrier frequency is in the range of 1100 MHz to 2000 MHz.