Abstract The invention relates to a device for adjusting the trigger timing of distance measuring equipment based on measuring the delay time for reflection of transmitted pulses of energy, e.g. echo-sounding equipment. The device comprises a detector designed to indicate whether an echo of prescribed characteristics is received within a prescribed period of time, or whether the echo fails to arrive. A phase comparator determines whether an echo of prescribed characteristics is received before or after the prescribed period of time. A variable-delay circuit is controlled by the detector and the phase comparator in order to delay the triggering of the transmitter of energy pulses, in such a way that echoes of prescribed characteristics will be received within the prescribed region of time, by maintaining the delay constant when the detector indicates echoes within the prescribed period of time, and by increasing or reducing the delay according to command from the phase comparator when the echo is received before or after the prescribed period of time, respectively. Applied to echo sounding apparatus the echo signal of the prescribed characteristic is usually constituted by the bottom echo signal, and in this case the present timing device will carry out an automatic recorder phasing to always secure a recording of the bottom contour within the automatically set recorder range, irrespectively of changing ocean depth.
A device for adjusting the trigger timing of distance measuring equipment measuring the delay time for reflection of transmitted pulses of energy comprising a transmitter for transmitting energy pulses; a detector for indicating an echo of prescribed characteristics received by said device within a prescribed period of time; a phase comparator for determining an echo of prescribed characteristics received before or after said prescribed period of time; and a variable-delay circuit controlled by said detector and said phase comparator to delay the triggering of said transmitter whereby echoes having prescribed characteristics are received by said device within said prescribed period of time by maintaining said delay of the transmitter triggering constant when said detector indicates echoes within said prescribed period of time, and by increasing or reducing said delay of the transmitter triggering in response to said phase comparator when the echo is received before or after said prescribed period of time, respectively.
Claim 2
Independent Claim
153 words
A device for adjusting the trigger timing of distance measuring equipment measuring the delay time for reflection of transmitted pulses of energy comprising a transmitter for transmitting energy pulses; a detector for indicating an echo of prescribed characteristics received by said device within a prescribed period of time; a phase comparator for determining an echo of prescribed characteristics received before or after said prescribed period of time; and a variable-delay circuit controlled by said detector and said phase comparator to delay the triggering of said transmitter whereby echoes having prescribed characteristics are received by said device within said prescribed period of time by maintaining said delay of the transmitter triggering constant when said detector indicates echoes within said prescribed period of time, and by increasing or reducing said delay of the transmitter triggering in response to said phase comparator when the echo is received before or after said prescribed period of time, respectively.
Claim 3
Dependent Claim
48 words
A device according to claim 1, wherein said detector includes means for detecting the absence of echoes having prescribed characteristics received by said device within said prescribed period of time for a preselected number of successive periods of time before the delay of said delay circuit is changed.