Patent ID: 6983131

Claim:
A circuit configuration for direct modulation, comprising: an oscillator having an output outputting a radio frequency signal; a first phase shifting device having an input and outputs for mutually phase-shifted signals; terminals for mutually phase-shifted signal components of a useful signal; a first mixer having a first input connected to a first output of said outputs of said first phase shifting device, a second input connected to a first terminal of said terminals, and an output for a first modulated signal; a second mixer having a first input connected to a second output of said outputs of said first phase shifting device, a second input connected to a second terminal of said terminals, and an output for a second modulated signal; a first combination device having inputs connected to said output of said first mixer and to said output of said second mixer, and an output for tapping off a modulated radio frequency signal modulated with the useful signal; a second phase shifting device having outputs for first mutually phase-shifted signals and an input coupled to said output of said oscillator; a third phase shifting device having outputs for second mutually phase-shifted signals and an input connected to a first output of said outputs of said second phase shifting device; a third mixer having inputs connected to a second output of said outputs of said second phase shifting device and to a first output of said outputs of said third phase shifting device, said third mixer further having an output for third a modulated signal; a fourth mixer having inputs connected to said first output of said second phase shifting device and to a second output of said outputs of said third phase shifting device, said fourth mixer further having an output for a fourth modulated signal; and a second combination device having inputs connected to said output of said third mixer and to said output of said fourth mixer, said second combination device further having an output connected to said input of said first phase shifting device.