System for monitoring the peak power of a telecommunication signal and method for calculating the peak value and for selecting the associated supply voltage

A system for tracking the peak power of a telecommunication signal to be transmitted for an RF power amplification of the telecommunication signal to be transmitted, comprising:

• an RF power amplifier having an RF input, a supply voltage input and an RF output,
• a digital processing device,
• a digital to RF converter, and
• a DC-DC converter,
• having an input for receiving the telecommunication signal to be transmitted in the form of digital data, a first output connected to an input of the digital to RF converter and a second output connected to an input of the DC-DC converter, the digital to RF converter having an output connected to the RF input of the RF power amplifier, the DC DC converter having an output connected to the supply voltage input of the RF power amplifier, the output of the DC DC converter assuming a discrete voltage value from among N discrete voltage values, N being an integer greater than or equal to 2, a delay element τ being provided between the input and the first ouput of the digital processing device, a processing chain being provided between the input and the second ouput of the digital processing device, the processing chain comprising an envelope tracking command logic for creating an envelope tracking command signal with N discrete levels from digital data received at the input of the digital processing device, the envelope tracking command signal with N discrete levels being sampled at a predetermined sampling frequency, wherein the processing chain further comprises, downstream from the envelope tracking command logic, a driver logic of the DC-DC converter comprising a device for calculating the peak value and a device for selecting the supply voltage, the device for calculating the peak value being configured to:
• window the envelope tracking command signal with N discrete levels, using a sliding time window, the duration of which is defined by a predefined number of samples of the envelope tracking command signal with N discrete levels, the offset between time windows being equal to a sample of the envelope tracking command signal with N discrete levels, and
• calculating calculate the maximum value of the envelope tracking command signal with N discrete levels over each time window of the sliding time window, being configured to command the DC-DC converter in order to impose, on the output of the DC-DC converter, from among the N discrete voltage values, as a function of the maximum value of the envelope tracking command signal with N discrete levels over the current time window, of the value of the envelope tracking command signal with N discrete levels delayed by the duration of the sliding time window and of the current value of the output of the device for selecting the supply voltage, a discrete supply voltage value greater than or equal to the envelope tracking command signal with N discrete levels, the discrete supply voltage value being applied during a minimum duration equal to the duration of the sliding time window.