Integrated video and audio signal distribution system and method for use on commercial aircraft and other vehicles

• US 5,617,331 A
• Filed: 06/07/1995
• Issued: 04/01/1997
• Est. Priority Date: 06/01/1993
• Status: Expired due to Term

• Current Assignee: Matsushita Avionics Development Corporation
• Original Assignee: Matsushita Avionics Development Corporation
• Inventors: Wakai, Bruce M., Lemmer, John E., Frost, William A. Jr.
• Primary Examiner(s): Voeltz, Emanuel T.
• Assistant Examiner(s): Assouad, Patrick J.
• Application Number:
  US08/480,666
• Time in Patent Office: 664 Days
• Field of Search: 364/514 A, 364/514 B, 364/514 C, 364/514 R, 381/82, 455/6.3, 455/3.1, 348/8, 340/310.02
• US Class Current: 725/76
• CPC Class Codes: B64D 11/0015 Arrangements for entertainment or communications, e.g. radio, television
• CPC Class Codes: B64D 11/00155 Individual entertainment or communication system remote controls therefor, located in or connected to seat components, e.g. to seat back or arm rest
• CPC Class Codes: H04H 20/62 for transportation systems, e.g. in vehicles
• CPC Class Codes: H04J 3/1605 Fixed allocated frame structures
• CPC Class Codes: H04N 7/10 Adaptations for transmission by electrical cable H04N7/12 takes precedence
• CPC Class Codes: H04N 7/106 for domestic distribution
• CPC Class Codes: H04N 7/18 Closed-circuit television [CCTV] systems, i.e. systems in which the video signal is not broadcast
• CPC Class Codes: H04R 2227/003 Digital PA systems using, e.g. LAN or internet
• CPC Class Codes: H04R 27/00 Public address systems circuits for preventing acoustic reaction H04R3/02; circuits for distributing signals to loudspeakers H04R3/12; monitoring or testing arrangements for public address systems H04R29/007; amplifiers H03F
• CPC Class Codes: H04R 29/007 for public address systems public address systems per se H04R27/00

Abstract

A passenger entertainment system employing an improved digital audio signal distribution system and method for use on commercial aircraft and other vehicles. A plurality of digital audio signal sources are provided for generating a plurality of compressed digital audio signals. The compressed digital audio signals are provided to a multiplexer which domain multiplexes those signals to produce a single composite digital audio data signal. The composite digital audio data signal is provided to a demultiplexer which is capable of selecting a desired channel from the composite digital audio data signal. The selected channel is provided to a decompression circuit, where it is expanded to produce a decompressed digital output signal. The decompressed digital output signal is then provided to a digital-to-analog converter and converted to an analog audio signal. The analog audio signal is provided to an audio transducer.

Claims

1. A passenger entertainment system for use on commercial aircraft and other vehicles comprising:

a plurality of digital audio signal sources for generating a first plurality of compressed digital audio signals;

a plurality of analog audio signal sources for generating a first plurality of analog audio signals;

a plurality of video signal sources for generating a first plurality of analog video signals and a plurality of video sourced analog audio signals;

a plurality of analog-to-digital converters for receiving said first plurality of analog audio signals and said plurality of video sourced analog audio signals and converting those signals to a digital format;

a plurality of digital signal compression circuits for receiving said signals converted to a digital format from said analog-to-digital converters and compressing said signals converted to a digital format to a format compatible with said first plurality of compressed digital audio signals generated by said digital audio signal sources to produce a second plurality of compressed digital audio signals;

a multiplexer for receiving said compressed digital audio signals generated by said digital audio signal sources and said digital signal compression circuits and multiplexing the signals delivered thereto to form a composite digital audio data signal;

a plurality of video signal modulators for receiving said analog video signals generated by said video signal sources and modulating said analog video signals on a plurality of distinct carrier frequencies;

a plurality of RF signal combiners for receiving said modulated analog video signals from said video signal modulators and combining the signals delivered thereto to form a composite RF video signal;

a baseband/RF signal combiner for receiving said composite digital audio data signal and said composite RF video signal and combining said composite digital audio data signal and said composite RF video signal to produce a composite RF video/digital audio data signal;

at least one RF signal separator for receiving said composite RF video/digital audio data signal and separating said composite RF video/digital audio data signal into its respective composite RF video and digital audio data components;

a demultiplexer adapted for receiving said digital audio data component of said RF video/digital audio data signal from said baseband/RF signal separator and selecting a desired digital audio channel from said digital audio data component;

a digital signal decompression circuit for receiving a selected digital audio channel from said demultiplexer and decompressing said selected channel from a compressed digital audio format to an expanded digital audio format;

a digital-to-analog converter for receiving said expanded channel from said digital signal decompression circuit, converting said expanded channel to an analog format, and delivering said converted and expanded channel to an audio transducer; and

an RF tuner for receiving said RF video component of said composite RF video/digital audio data signal from said RF signal separator, selecting a desired video channel from said RF video component, and providing a selected video channel to a video monitor for display;

whereby each of said first plurality of compressed digital audio signals may be delivered to said digital signal decompression circuit without having previously been delivered to an analog-to-digital conversion circuit.

2. The passenger entertainment system of claim 1 wherein

said composite digital audio data signal comprises a plurality of compression blocks having F frames per block, C digital audio channels per frame, and P compression parameters per channel per block;

said multiplexer is configured to allocate N time slots per frame for said compression parameters, N being an integer equal to or greater than (C×

P)/F; and

said multiplexer assigns selected groups comprising N of said compression parameters to selected frames within each compression block.

3. The passenger entertainment system of claim 1 wherein said carrier frequencies are programmably variable between 135 MHz and 300 MHz.

4. A passenger entertainment system for use on commercial aircraft and other vehicles comprising:

a plurality of digital audio signal sources for generating a first plurality of compressed digital audio signals;

a plurality of analog audio signal sources for generating a first plurality of analog audio signals;

a plurality of video signal sources for generating a first plurality of analog video signals and a plurality of video sourced analog audio signals;

a plurality of analog-to-digital converters for receiving said first plurality of analog audio signals and said plurality of video sourced analog audio signals and converting those signals to a digital format;

a plurality of digital signal compression circuits for receiving said signals converted to a digital format from said analog-to-digital converters and compressing said signals converted to a digital format to a format compatible with said first plurality of compressed digital audio signals generated by said digital audio signal sources to produce a second plurality of compressed digital audio signals;

a multiplexer for receiving said compressed digital audio signals generated by said digital audio signal sources and said digital signal compression circuits and multiplexing the signals delivered thereto to form a composite digital audio data signal;

a plurality of video signal modulators for receiving said analog video signals generated by said video signal sources and modulating said analog video signals on a plurality of distinct carrier frequencies;

a plurality of RF signal combiners for receiving said modulated analog video signals from said video signal modulators and combining the signals delivered thereto to form a composite RF video signal;

a baseband/RF signal combiner for receiving said composite digital audio data signal and said composite RF video signal and combining said composite digital audio data signal and said composite RF video signal to produce a composite RF video/digital audio data signal;

at least one RF signal separator for receiving said composite RF video/digital audio data signal and separating said composite RF video/digital audio data signal into its respective composite RF video and digital audio data components;

a demultiplexer adapted for receiving said digital audio data component of said RF video/digital audio data signal from said baseband/RF signal separator and selecting a desired digital audio channel from said digital audio data component;

a digital signal decompression circuit for receiving a selected digital audio channel from said demultiplexer and decompressing said selected channel from a compressed digital audio format to an expanded digital audio format;

a digital-to-analog converter for receiving said expanded channel from said digital signal decompression circuit, converting said expanded channel to an analog format, and delivering said converted and expanded channel to an audio transducer; and

an RF tuner for receiving said RF video component of said composite RF video/digital audio data signal from said RF signal separator, selecting a desired video channel from said RF video component, and providing a selected video channel to a video monitor for display;

wherein

said composite digital audio data signal comprises a plurality of compression blocks having F flames per block, C digital audio channels per frame, and P compression parameters per channel per block;

said multiplexer is configured to allocate N time slots per frame for said compression parameters, N being an integer equal to or greater than (C×

P)/F; and

said multiplexer assigns selected groups comprising N of said compression parameters to selected frames within each compression block.