Delay distortion measurement system

Claim 1

The method of measuring frequency delay distortion of a communication channel which comprises: generating at a sending end of said channel a plurality of sustained sine wave signals distributed throughout a frequency spectrum of said channel, modulating at a lower frequency each of said sine wave signals in repetitive progression for a preselected period of each, transmitting said modulated signals over said channel to its distant end, and at said distant end, locally generating a signal of frequency substantially that of said modulating frequency, selectively detecting one of said plurality of sine wave signals, and upon said detection synchronizing the frequency of said locally generated signal with the modulating frequency of the received signals, and concurrently therewith, detecting and filtering all of said modulating incoming signals into signals of said modulating frequency, and measuring the difference in time between that at which any said detected and filtered signal goes to zero and that at which said locally generated, synchronized signal goes to zero for adjacent cycles timewise thereof respectively.

Claim 2

The method of measuring frequency delay distortion of a communication channel which comprises: generating at a sending end of said channel a plurality of sustained sine wave signals distributed throughout a frequency spectrum of said channel, modulating at a lower frequency each of said sine wave signals in repetitive progression for a preselected period of each, transmitting said modulated signals over said channel to its distant end, and at said distant end, locally generating a signal of frequency substantially that of said modulating frequency, selectively detecting one of said plurality of sine wave signals, and upon said detection synchronizing the frequency of said locally generated signal with the modulating frequency of the received signals, and concurrently therewith, detecting and filtering all of said modulating incoming signals into signals of said modulating frequency, and measuring the difference in time between that at which any said detected and filtered signal goes to zero and that at which said locally generated, synchronized signal goes to zero for adjacent cycles timewise thereof respectively.

Claim 4

The method of measuring frequency delay distortion of a communication channel which comprises: generating at a sending end of said channel a plurality of sustained sine wave signals distributed throughout a frequency spectrum of said channel, modulating at a lower frequency each of said sine wave signals in repetitive progression for a preselected period of each, transmitting said modulated signals over said channel to its distant end, and at said distant end, locally generating a substantially square wave signal of frequency substantially that of said modulating frequency, selectively detecting one of said plurality of sine wave signals, and upon said detection synchronizing the frequency said locally generated signal with the modulating frequency of the received signals, and concurrently therewith, detecting and filtering all of said modulated received signals and converting to substantially square wave signals of the periodicity of said modulating frequency, and measuring the difference in time between that at which any said detected and filtered square wave signal goes to zero and that of which said locally generated, synchronized, square wave signal goes to zero for adjacent cycles timewise thereof respectively.

Claim 5

The method of measuring frequency delay distortion of a communication channel which comprises: generating at a sending end of said channel a plurality of sustained sine wave signals distributed throughout a frequency spectrum of said channel, modulating at a lower frequency each of said sine wave signals in repetitive progression for a preselected period of each, transmitting said modulated signals over said channel to its distant end, and at said distant end, locally generating a substantially square wave signal of frequency substantially that of said modulating frequency, selectively detecting one of said plurality of sine wave signals, and upon said detection synchronizing the frequency said locally generated signal with the modulating frequency of the received signals, and concurrently therewith, detecting and filtering all of said modulated received signals and converting to substantially square wave signals of the periodicity of said modulating frequency, and measuring the difference in time between that at which any said detected and filtered square wave signal goes to zero and that of which said locally generated, synchronized, square wave signal goes to zero for adjacent cycles timewise thereof respectively.

Claim 8

The method of measuring frequency delay distortion of a communication channel which comprises: concurrently generating at a sending end of said channel a plurality of sustained sine wave signals distributed throughout a frequency spectrum of said channel, modulating at a lower frequency each of said sine wave signals in repetitive progression thereof and for a preselected period of each, transmitting said modulated signals over said channel to its distant end, and at said distant end, locally generating a signal of frequency substantially that of said modulating frequency, selectively detecting one of said plurality of sine wave signals by demodulation of the incoming carrier wave signals, thereupon adjusting the frequency and phase of said locally generated signal to exact synchronism with the modulating frequency of the received modulated signals, meantime detecting and filtering all of said modulated received signals and converting to substantially square wave signals each of zero average amplitude and of the periodicity of said modulating frequency, converting said locally generated synchronized signal to a substantially square wave signal of zero average amplitude and measuring the difference in time between that at which any said detected and filtered signal goes to zero and that at which said locally generated signal goes to zero for adjacent cycles timewise thereof respectively.

Claim 9

The method of measuring frequency delay distortion of a communication channel which comprises: concurrently generating at a sending end of said channel a plurality of sustained sine wave signals distributed throughout a frequency spectrum of said channel, modulating at a lower frequency each of said sine wave signals in repetitive progression thereof and for a preselected period of each, transmitting said modulated signals over said channel to its distant end, and at said distant end, locally generating a signal of frequency substantially that of said modulating frequency, selectively detecting one of said plurality of sine wave signals by demodulation of the incoming carrier wave signals, thereupon adjusting the frequency and phase of said locally generated signal to exact synchronism with the modulating frequency of the received modulated signals, meantime detecting and filtering all of said modulated received signals and converting to substantially square wave signals each of zero average amplitude and of the periodicity of said modulating frequency, converting said locally generated synchronized signal to a substantially square wave signal of zero average amplitude and measuring the difference in time between that at which any said detected and filtered signal goes to zero and that at which said locally generated signal goes to zero for adjacent cycles timewise thereof respectively.

Claim 10

The method of measuring frequency delay distortion of a communication channel which comprises: generating at a sending end of said channel a plurality of sustained sine wave signals distributed throughout a frequency spectrum of said channel, modulating at a lower frequency each of said sine wave signals in repetitive progression for a preselected period of each, transmitting said modulated signals over said channel to its distant end, and at said distant end, locally generating a signal of frequency substantially that of said modulating frequency, detecting and filtering all of said modulated incoming signals into signals of the periodicity of said modulating frequency, measuring the difference in time between that at which each of said detected and filtered signals goes to zero and that at which said locally generated signal, goes to zero for adjacent cycles timewise thereof respectively, thereupon synchronizing said locally generated signal frequency with the incoming modulating frequency, and applying the time delay of any such frequency adjustment required as a constant correction factor to said difference in time measurements.

Claim 11

The method of measuring frequency delay distortion of a communication channel which comprises: generating at a sending end of said channel a plurality of sustained sine wave signals distributed throughout a frequency spectrum of said channel, modulating at a lower frequency each of said sine wave signals in repetitive progression for a preselected period of each, transmitting said modulated signals over said channel to its distant end, and at said distant end, locally generating a signal of frequency substantially that of said modulating frequency, detecting and filtering all of said modulated incoming signals into signals of the periodicity of said modulating frequency, measuring the difference in time between that at which each of said detected and filtered signals goes to zero and that at which said locally generated signal, goes to zero for adjacent cycles timewise thereof respectively, thereupon synchronizing said locally generated signal frequency with the incoming modulating frequency, and applying the time delay of any such frequency adjustment required as a constant correction factor to said difference in time measurements.