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

• US 5,596,647 A
• Filed: 06/01/1993
• Issued: 01/21/1997
• Est. Priority Date: 06/01/1993
• Status: Expired due to Term

• Current Assignee: Panasonic Avionics Corporation (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Avionics Development Corporation
• Inventors: Frost, William A. Jr., Wakai, Bruce M., Lemmer, John E.
• Primary Examiner(s): BRINICH, STEPHEN M
• Application Number:
  US08/071,218
• Time in Patent Office: 1,330 Days
• Field of Search: 381/77, 381/29, 381/31, 348/8, 348/836, 370/7, 370/118
• US Class Current: 381/77
• 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 digital audio distribution system for use on aircraft and other vehicles comprising:

a plurality of digital signal sources for generating a plurality of compressed digital audio signal outputs;

a multiplexer having a plurality of signal input terminals for receiving said compressed digital audio signal outputs, said multiplexer being adapted to time domain multiplex said compressed digital audio signal outputs to produce a single composite data signal;

a demultiplexer adapted to receive said composite data signal and to select a desired channel from said composite data signal;

a decompression circuit adapted to receive said selected channel from said demultiplexer and to decompress said selected channel to produce a decompressed digital output signal; and

a digital-to-analog converter adapted to receive said decompressed digital output signal and to convert said decompressed digital output signal to an analog audio signal;

wherein

said composite 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;

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 factors to selected frames within each compression block.

2. A method of distributing within an commercial aircraft or other passenger vehicle, said method comprising the steps of:

generating a plurality of compressed digital audio signal outputs;

providing said plurality of compressed digital audio signal outputs directly to a multiplexer;

time domain multiplexing said compressed digital audio signal outputs to produce a composite digital audio data signal;

delivering said composite digital audio data signal to a demultiplexer disposed at a location remote from said multiplexer;

selecting a channel from said composite digital audio data signal;

decompressing said selected channel to produce an expanded digital audio signal;

converting said expanded digital audio signal to an analog signal; and

providing said analog audio signal to an audio transducer;

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; and

said time domain multiplexing step comprises the steps of;

allocating N time slots per frame for said compression parameters, N being an integer equal to or greater than (CxP)/F; and

assigning selected groups comprising N of said compression factors to selected frames within each compression block.