Radiofrequency transmitter with a high degree of integration and possibly with self-calibrating image deletion

摘要

A radio frequency transmitter, of the type supplied with two signals in baseband and in quadrature, I(nT) and q(nT), which are images from two binary streams representing information to be transmitted, 1) provides a first transposition into the digital domain, at an intermediate frequency ω₀, for the baseband signals and generates, by combination, two signals of intermediate frequency in quadrature, 2) provides a second transposition into the analog domain, after multiplication by a frequency ω₁, followed by a summation of the two signals at intermediate frequency and in quadrature, in such a way that a resultant signal is generated which is found finally around a frequency ω₂, where ω₂=ω₀+ω₁. In an advantageous variant, the radio frequency transmitter additionally digitally compensates gain and phase imperfections of the direct conversion.