Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
356 words
In a combined passenger entertainment and service syStem: a multiplexed audio distribution subsystem comprising: a main multiplexer for converting a plurality of channels of audio input signals into a single digital bit stream including stereo/mono bits to indicate the presence of stereo signals, and a plurality of demultiplexers for reconverting selected portions of said digital bit stream corresponding to selected channels into audio signals, including stereo signals when indicated; a passenger reading light and attendant call service subsystem comprising: a plurality of seat encoders associated with respective ones of said demultiplexers for generating control data in accordance with individual passenger requests, said encoders being serially connected one to another by means of bidirectional gated data switches, a plurality of serially connected overhead decoders for decoding reading light control data and controlling overhead reading lights in accordance therewith, a timer-decoder directly connected to at least one of said seat encoders and to at least one of said overhead decoders for providing timing and control data to said encoders and decoders and for decoding attendant call control data from said seat encoders, and an attendant control panel associated with said timer-decoder for controlling all reading lights and all attendant call lights; and a self-test subsystem for testing said multiplex audio distribution subsystem, using said service subsystem for providing a visual indication of test results, comprising: a digital test signal generator, means for converting the output of said test signal generator into a single digital bit stream having a format compatible with said multiplexed audio distribution subsystem, said stereo/mono bits being used to indicate the presence of a self-test signal, means associated with each of said seat encoders for recognizing whether said stereo/mono bits indicate the presence of a self-test signal, for converting (using the circuits of the associated demultiplexer) said self-test signal into an analog self-test signal, and for comparing the amplitude of said analog self-test signal with a predetermined threshold, and means for causing the associated seat encoder to generate appropriate light control data, whereby a visual indication is given by said service subsystem of test results whenever said analog self-test signal amplitude exceeds said predetermined threshold.
Claim 2
Dependent Claim
356 words
In a combined passenger entertainment and service syStem: a multiplexed audio distribution subsystem comprising: a main multiplexer for converting a plurality of channels of audio input signals into a single digital bit stream including stereo/mono bits to indicate the presence of stereo signals, and a plurality of demultiplexers for reconverting selected portions of said digital bit stream corresponding to selected channels into audio signals, including stereo signals when indicated; a passenger reading light and attendant call service subsystem comprising: a plurality of seat encoders associated with respective ones of said demultiplexers for generating control data in accordance with individual passenger requests, said encoders being serially connected one to another by means of bidirectional gated data switches, a plurality of serially connected overhead decoders for decoding reading light control data and controlling overhead reading lights in accordance therewith, a timer-decoder directly connected to at least one of said seat encoders and to at least one of said overhead decoders for providing timing and control data to said encoders and decoders and for decoding attendant call control data from said seat encoders, and an attendant control panel associated with said timer-decoder for controlling all reading lights and all attendant call lights; and a self-test subsystem for testing said multiplex audio distribution subsystem, using said service subsystem for providing a visual indication of test results, comprising: a digital test signal generator, means for converting the output of said test signal generator into a single digital bit stream having a format compatible with said multiplexed audio distribution subsystem, said stereo/mono bits being used to indicate the presence of a self-test signal, means associated with each of said seat encoders for recognizing whether said stereo/mono bits indicate the presence of a self-test signal, for converting (using the circuits of the associated demultiplexer) said self-test signal into an analog self-test signal, and for comparing the amplitude of said analog self-test signal with a predetermined threshold, and means for causing the associated seat encoder to generate appropriate light control data, whereby a visual indication is given by said service subsystem of test results whenever said analog self-test signal amplitude exceeds said predetermined threshold.
Claim 3
Dependent Claim
68 words
The combined passenger entertainment and service system of claim 1 wherein said audio distribution system further comprises a pair of audio transducers at each seat location and said self-test subsystem further comprises means for checking the electrical continuity of each transducer pair and means for causing the associated seat encoder to generate distinctive light control data whenever there is a failure in the electrical continuity of said pair.
Claim 4
Dependent Claim
34 words
The system of claim 2 wherein said self-test signal is a digitized low frequency squarewave signal and said distinctive light control data causes the flashing of an overhead reading light at said low frequency.
Claim 5
Dependent Claim
58 words
The system of claim 1 wherein said stereo/mono bits consist of one bit per channel per sample, said bit in combination with the corresponding bit of the immediately preceding channel giving a total of four states signifying respectively: a. both channels mono, b. both channels forming a single stereo channel, c. self-test mode, d. public address override mode.
Claim 6
Dependent Claim
38 words
The system of claim 4 wherein both self-test mode and public address override mode inhibit the addition of other audio channels into said digital stream, thereby ensuring that all channels carry self-test data or public address data respectively.
Claim 7
Dependent Claim
39 words
The system of claim 1 wherein said multiplexed audio distribution subsystem further comprises a plurality of submultiplexers for distributing said digital bit stream and optionally inserting therein digital information representing additional audio inpuTs including movie audio and public address.
Claim 8
Dependent Claim
18 words
The system of claim 6 wherein said movie audio input overrides predetermined audio outputs from said main multiplexer.
Claim 9
Dependent Claim
16 words
The system of claim 6 wherein said public address audio is output simultaneously on all channels.
Claim 10
Dependent Claim
230 words
In a combined passenger entertainment and service system, a ''''daisy chain'''' arrangement for controlling overhead reading lights, said arrangement comprising: a timer-decoder, seat encoders serially connected one to another for transmitting passenger service request control data via a first gated data line, overhead decoders serially connected one to another for receiving said control data via a second gated data line; a forward data connection between said timer-decoder and the first of said seat encoders; a forward data connection between said timer-decoder and the first of said overhead decoders; a backward data connection between said timer-decoder and the last of said serially connected seat encoders; a backward data connection between said timer-decoder and the last of said serially connected overhead decoders; a common clock line connected from said timer-decoder to all of said encoders and decoders; means within said timer-decoder for alternating between forward and backward cycles initiated by strobe pulses applied to said forward data connections and said backward data connections respectively; an end-of-frame strobe pulse to a succeeding encoder-decoder pair from the preceding encoder-decoder pair via said first and second gated data lines respectively for enabling said succeeding encoder-decoder pair to transmit and receive control data; an end-of-cycle synchronization pulse to all of said encoders and decoders via said common clock line for resetting all said encoders and decoders; and means associated with said timer-decoder for detecting a failure.
Claim 11
Dependent Claim
230 words
In a combined passenger entertainment and service system, a ''''daisy chain'''' arrangement for controlling overhead reading lights, said arrangement comprising: a timer-decoder, seat encoders serially connected one to another for transmitting passenger service request control data via a first gated data line, overhead decoders serially connected one to another for receiving said control data via a second gated data line; a forward data connection between said timer-decoder and the first of said seat encoders; a forward data connection between said timer-decoder and the first of said overhead decoders; a backward data connection between said timer-decoder and the last of said serially connected seat encoders; a backward data connection between said timer-decoder and the last of said serially connected overhead decoders; a common clock line connected from said timer-decoder to all of said encoders and decoders; means within said timer-decoder for alternating between forward and backward cycles initiated by strobe pulses applied to said forward data connections and said backward data connections respectively; an end-of-frame strobe pulse to a succeeding encoder-decoder pair from the preceding encoder-decoder pair via said first and second gated data lines respectively for enabling said succeeding encoder-decoder pair to transmit and receive control data; an end-of-cycle synchronization pulse to all of said encoders and decoders via said common clock line for resetting all said encoders and decoders; and means associated with said timer-decoder for detecting a failure.
Claim 12
Dependent Claim
48 words
The ''''daisy chain'''' arrangement of claim 9 wherein said means for detecting a failure comprises a counter for counting the number of frames within a cycle and a strobe pulse detector for detecting the strobe pulse from the last of said serially connected decoders in a given cycle.
Claim 13
Dependent Claim
34 words
The ''''daisy chain'''' arrangement of claim 9 wherein said means for detecting a failure comprises a permanent one bit in the control data output of each seat encoder and means for detecting said bit.
Claim 14
Dependent Claim
28 words
The ''''daisy chain'''' arrangement of claim 9 further comprising means for initiating the start of the next cycle upon the detection of a failure within a given cycle.