Direct conversion device with compensation means for a transmission path of a wireless communication equipment

Abstract

A conversion device (CD) is dedicated to conversion of baseband analog I/Q input signals into RF signals in a transmitting path of a wireless communication equipment. This device (CD) comprises i) first (PP) and second (PP) processing paths each comprising i) an input node (IN, IN) receiving an input signal (I/Q), i) an input path (IP, IP) connected to the input node and delivering an input current representative of the input signal (I/Q), i) an amplification means (A, A) having first and second inputs fed with the input current and a common-mode current and outputting an amplified signal, and i) a transconductor (T, T) delivering first and second currents from the amplified signal, the first current feeding a negative feedback path connected to the first input of the amplification means and being essentially equal to the input current, and the second current being a chosen scaled copy of the first current and representative of a voltage difference between the input signals (I/Q), H) a common-mode input path (CIP) connected to the input nodes (IN, IN) and delivering the common-mode current from the input signals (I/Q) to feed the second input of each amplification means (A, A), and iii) a switch core (SC) for mixing the second current delivered by a chosen one of the transconductors (T, T) with a local oscillator RF carrier to deliver output RF signals representative of the input signals (I/Q).