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AssigneeMesserschmitt-Boelkow-Blohm Gesellschaft mit beschraenkter Haftung
InventorsHermann Kraus, Peter Kirchlechner, Robert Rieger, Wolf-Dieter Schuck
Estimating the term…
The synchronism or tracking between two analog signals is compared by a cuit arrangement having two inputs to which these analog signals are applied. A comparator circuit compares the two signals and provides a trigger or energizing signal to a switch which in turn produces an error signal when the two compared signals deviate from each other to an extent larger than a predetermined limit. One input is connected to the comparator circuit through a heterodyning circuit wherein the respective analog signal is heterodyned by a heterodyning signal which varies in its polarity. The comparator circuit includes a polarity detector which provides a signal signifying a positive or a negative difference between the amplitudes of the two polarity signals. A discriminator circuit is operatively connected to the comparator to provide a switch energizing signal when the difference signal does not have any zero transitions or passages with the frequency of the heterodyning signal.
A circuit arrangement for the comparing of the synchronism of two analog signals, comprising first and second signal input means for said two analog signals, signal comparator means, means connecting said signal input means to said signal comparator means, said connecting means comprising at least one heterodyning means operatively connecting one of said signal input means to said signal comparator means, whereby at least one of said analog signals is heterodyned by a heterodyning signal having a given frequency and an alternating polarity, said signal comparator means comprising signal difference forming means and signal polarity detecting means operatively connected to said signal difference forming means for producing a difference signal signifying a positive or negative difference between said analog signals, and discriminator circuit means operatively connected to said comparator means for producing an error signal in response to the fact that difference signal zero transitions having said given frequency of said heterodyning signal are absent, said circuit arrangement further comprising feedback circuit means operatively interconnecting said comparator means and said heterodyning means for a self-oscillating operation.
Dependencies are inferred from the claim text.