Method for correlating frequency-modulated signals

Claim 1

A method for correlating frequency-modulated signal wavetrains with their return-signal wavetrains after propagation through a distorting medium comprising the steps of: generating a frequency-modulated, repeatable series of electrical undulations known as the ''''original reference function''''; transmitting said original reference function through a medium after passing it through suitable transmitting electronic equipment to prepare it for transmission through such a medium; receiving the transmitted signal and passing it through suitable receiving electronic equipment to derive a medium-andequipment-distorted signal therefrom; passing said original reference function through means which simulate the transfer function of the transmitting and receiving electronic equipment through which said original reference function has passed and through means which simulate the transfer function of said medium according to the range in the medium over which the signal has been propagated, the final signal being known as the ''''evolved reference function''''; making a record of the evolved reference function; and correlating the medium-and-equipment-distorted signal with the evolved reference function.

Claim 2

A method for correlating frequency-modulated signal wavetrains with their return-signal wavetrains after propagation through a distorting medium comprising the steps of: generating a frequency-modulated, repeatable series of electrical undulations known as the ''''original reference function''''; transmitting said original reference function through a medium after passing it through suitable transmitting electronic equipment to prepare it for transmission through such a medium; receiving the transmitted signal and passing it through suitable receiving electronic equipment to derive a medium-andequipment-distorted signal therefrom; passing said original reference function through means which simulate the transfer function of the transmitting and receiving electronic equipment through which said original reference function has passed and through means which simulate the transfer function of said medium according to the range in the medium over which the signal has been propagated, the final signal being known as the ''''evolved reference function''''; making a record of the evolved reference function; and correlating the medium-and-equipment-distorted signal with the evolved reference function.

Claim 3

A method for correlating frequency-modulated signal wavetrains with their return-signal wavetrains after propagation through a distorting medium comprising the steps of: generating a frequency-modulated, repeatable series of electrical undulations known as the ''''original reference function''''; transmitting said original reference function through a medium after passing it through suitable transmitting electronic equipment to prepare it for transmission through such a medium; receiving the transmitted signal and passing it through suitable receiving electronic equipment to derive a medium-and-equipment-distorted signal therefrom; passing said original reference function through means which simulate the transfer function of the transmitting and receiving electronic equipment through which said original reference function has passed and through means which simulate the transfer function of said medium according to the range in the medium over which the signal has been propagated, the final signal being known as the ''''evolved reference function''''; making a record of the evolved reference function, said record comprising the analog of a series of evolved reference functions, each succeeding one being for a greater range than the previous one; and correlating the medium-and-equipment-distorted signal with the evolved reference function.

Claim 4

A method for correlating frequency-modulated signal wavetrains with their return-signal wavetrains after propagation through a distorting medium comprising the steps of: generating a frequency-modulated, repeatable series of electrical undulations known as the ''''original reference function''''; transmitting said original reference function through a medium after passing it through suitable transmitting electronic equipment to prepare it for transmission through such a medium; receiving the transmitted signal and passing it through suitable receiving electronic equipment to derive a medium-and-equipment-distorted signal therefrom; passing said original reference function through means which simulate the transfer function of the transmitting and receiving electronic equipment through which said original reference function has passed and through means which simulate the transfer function of said medium according to the range in the medium over which the signal has been propagated, the final signal being known as the ''''evolved reference function''''; making a record of the evolved reference function, said record comprising the analog of a series of evolved reference functions, each succeeding one being for a greater range than the previous one; and correlating the medium-and-equipment-distorted signal with the evolved reference function.

Claim 5

A method for correlating frequency-modulated signal wavetrains with their return-signal wavetrains after propagation through a distorting medium comprising the steps of: generating a frequency-modulated, repeatable series of electrical undulations known as the ''''original reference function''''; transmitting said original reference function through a medium after passing it through suitable transmitting electronic equipment to prepare it for transmission through such a medium; receiving the transmitted signal and passing it through suitable receiving electronic equipment to derive a medium-and-equipment-distorted signal therefrom; passing said original reference function through means which simulate the transfer function of the transmitting and receiving electronic equipment through which said original reference function has passed and through means which simulate the transfer function of said medium according to the range in the medium over which the signal has been propagated, the final signal being known as the ''''evolved reference function''''; making a record of the evolved reference function, said record comprising the analog of a series of evolved reference functions, each succeeding one being for a greater range than the previous one, said record being made on a continuous loop of recording material; and correlating the medium-and-equipment-distorted signal with the evolved reference function.

Claim 6

A method for correlating frequency-modulated signal wavetrains with their return-signal wavetrains after propagation through a distorting medium comprising the steps of: generating a frequency-modulated, repeatable series of electrical undulations known as the ''''original reference function''''; transmitting said original reference function through a medium after passing it through suitable transmitting electronic equipment to prepare it for transmission through such a medium; receiving the transmitted signal and passing it through suitable receiving electronic equipment to derive a medium-and-equipment-distorted signal therefrom; passing said original reference function through means which simulate the transfer function of the transmitting and receiving electronic equipment through which said original reference function has passed and through means which simulate the transfer function of said medium according to the range in the medium over which the signal has been propagated, the final signal being known as the ''''evolved reference function''''; making a record of the evolved reference function, said record comprising the analog of a series of evolved reference functions, each succeeding one being for a greater range than the previous one, said record being made on a continuous loop of recording material; and correlating the medium-and-equipment-distorted signal with the evolved reference function.