Returned reference compatible, straightaway envelope delay measurement instrument and method

The method of delay measurement, comprising creating a sinewave signal in a sinewave generator, creating a first lower frequency modulation oscillation signal in a low frequency modulation oscillator, modulating the sinewave signal with the low frequency oscillation, providing the modulated sinewave signal on a transmission path, detecting the modulated sinewave signal with an envelope detector remotely mounted in a delay measuring unit on the transmission path, providing a second low frequency reference oscillation signal and detecting phase difference between the first low frequency modulation oscillation signal from the envelope detector and the second low frequency reference oscillation signal, providing the detected phase delay signal to a reference oscillator difference error correction processor, and measuring total delay difference by subtracting a start delay from an end delay where the start and end frequencies of the sinewave generator are the same.

The method of straightaway envelope delay measurement, comprising measuring envelope delay by modulating a signal having an envelope with a low frequency modulation, transmitting the modulated envelope, signal detecting the envelope and recovering the low frequency modulation from the envelope, comparing phase of the recovered modulation with phase of a similar low frequency reference signal from a reference oscillator, and measuring envelope delay as a difference in phase of the modulation of the detected envelope compared to the low frequency reference.

A returned reference compatible, straightaway envelope delay measurement instrument apparatus for measuring delay in a transmission path, comprising a modulation source, a variable frequency sinewave generator and an amplitude modulator connected to the sinewave generator and connected to the modulation source, the amplitude modulator being provided for connecting to the transmission path, an envelope detector for connecting to the transmission path remote from the amplitude modulator, a phase detector connected to the envelope detector, a reference oscillator connected to the phase detector, a reference oscillator difference error correction processor connected to the phase detector, and a measurement display connected to the processor.

The method of delay measurement, comprising creating a sinewave signal in a sinewave generator, providing a first low frequency modulation oscillation signal from a low frequency modulation source, modulating the sinewave signal with the low frequency oscillation, providing the modulated sinewave signal on a transmission path, detecting the modulated sinewave signal with an envelope detector remotely mounted in a delay measuring unit on the transmission path, providing a second low frequency reference oscillation signal and detecting phase difference between the first low frequency modulation oscillation signal from the envelope detector and the second low frequency reference oscillation signal, providing the detected phase delay signal to a reference oscillator difference error correction processor, and measuring total delay difference by subtracting the start delay from the end delay where the start and end frequencies of the sinewave generator are the same.

The method of straightaway envelope delay measurement, comprising measuring envelope delay by providing a first sinewave, amplitude modulating the first sinewave with a first low frequency modulation, transmitting the first modulated sinewave, receiving the first modulated sinewave, detecting and recovering the first low frequency modulation from the first modulated sinewave, comparing phase of the recovered modulation with phase of a second low frequency reference signal from a reference oscillator, and measuring envelope delay as a difference in phase of the detected modulation compared to the second low frequency reference signal.