Modulator, included in a carrier frequency system wherein the carrier signal periodically interrupts the information signal during the modulation process

Claim 2

A modulator comprising a first and second input terminal for receiving a modulating voltage signal, a first and a second output terminal for transmitting a modulated carrier voltage signal, a voltage controlled impedance means having a first and a second output electrode and having a first and a second control electrode, means for connecting at least one of said output electrodes to one of said output terminals, means for connecting at least one of said input terminals to one of said output electrodes, a pulse waveform carrier frequency signal source, means for connecting said carrier frequency signal source to the first control electrode of said voltage controlled impedance means for switching the same between a conductive and nonconductive state, a voltage divider means, means for connecting said voltage divider means across the output electrodes of said controlled impedance means, and means for connecting an intermediate point of said divider means to the second control electrode of said controlled impedance means for reducing the influence of disturbing side-band components in the frequency spectrum of said modulated carrier voltage signal.

Claim 3

A modulator as claimed in claim 1 wherein said voltage controlled impedance means comprises a dual gate field effect transistor, the gate electrodes of which forming said first and second control electrodes and the source and drain electrodes of which forming said output electrodes, respectively.

Claim 4

A modulator as claimed in claim 2, wherein the field effect transistor comprises an integrated MOS-field effect transistor.

Claim 5

A modulator as claimed in claim 2, wherein said voltage divider means comprises two resistors, the common point of which being connected to said second control electrode, the ratio of the resistance values being dimensioned in dependence on the transistor type used.

Claim 6

A modulator as claimed in claim 1 further comprising a load means for receiving a modulated carrier voltage signal, means for connecting the other of said input terminals to the other of said output electrodes, means connecting one of said output terminals to one end of said load means, means including a resistor for connecting the other of said output terminals to the other end of said load means, and means for connecting the other of said output electrodes to the other of said output terminals.

Claim 7

A modulator as claimed in claim 1 wherein said means for connecting said voltage divider means includes means for connecting one end of said voltage divider means to one of said output electrodes, means for connecting the other end of said voltage divider means to the other of said output terminals, a signal load means for connecting said other output terminal to the other of said output electrodes, and further comprising means for connecting the other of said input terminals to the other of said output electrodes via said load means.

Claim 8

A modulator comprising: first and second voltage controlled impedance means, each comprising first and second output electrodes and first and second control electrodes; first and second carriEr frequency signal sources operating with the same frequency but in phase opposition; first and second modulating signal sources operating with the same signals but in phase opposition; a modulated signal load; means for connecting the first output electrodes of each of said voltage controlled impedance means in parallel to said signal load; means for connecting said first and second carrier frequency signal sources to the first control electrodes of each of said voltage controlled impedance means respectively; means for connecting said first and second modulating signal sources to the second output electrodes of each of said voltage controlled impedance means, respectively; and voltage divider interconnecting means for connecting the second output electrode of one of said voltage controlled impedance means to the second output electrode of the other of said voltage controlled impedance means via connections to the second controlled electrodes of each of said impedance means.

Claim 9

A modulator comprising: first and second voltage controlled impedance means, each comprising first and second output electrodes and first and second control electrodes; first and second carriEr frequency signal sources operating with the same frequency but in phase opposition; first and second modulating signal sources operating with the same signals but in phase opposition; a modulated signal load; means for connecting the first output electrodes of each of said voltage controlled impedance means in parallel to said signal load; means for connecting said first and second carrier frequency signal sources to the first control electrodes of each of said voltage controlled impedance means respectively; means for connecting said first and second modulating signal sources to the second output electrodes of each of said voltage controlled impedance means, respectively; and voltage divider interconnecting means for connecting the second output electrode of one of said voltage controlled impedance means to the second output electrode of the other of said voltage controlled impedance means via connections to the second controlled electrodes of each of said impedance means.

Claim 10

A modulator as claimed in claim 7 wherein said voltage controlled impedance means comprises a dual gate field effect transistor, the gate electrodes of which forming said first and second control electrodes and the source and drain electrodes of which forming said output electrodes, respectively.

Claim 11

A modulator as claimed in claim 8, wherein the field effect transistor comprises an integrated MOS-field effect transistor.

Claim 12

A modulator as claimed in claim 7 wherein said voltage divider interconnecting means comprises a first resistor for interconnecting the second output electrode and first control electrode of said first voltage controlled impedance means, a second resistor for interconnecting the second output electrode and first control electrode of said second voltage controlled impedance means, and a third resistor interconnecting the second control electrodes of said voltage controlled impedance means.