This article describes a 10-GHz chirp generator for frequency-modulated continuous-wave (FMCW) radars, that is based on a digital PLL (DPLL) with a two-point injection of the modulation signal. A new digital predistortion (DPD) algorithm is introduced that is specifically tailored to mitigate the impact of the nonlinear non-smooth tuning curve of a digitally controlled oscillator (DCO) optimized for a low phase noise. The algorithm estimates in the background a non-uniform piecewise parabolic (PWP) interpolation of the digital inverse of the DCO tuning curve, using an adaptive set of non-uniformly distributed breakpoints. The breakpoints are automatically placed at the corner points of the tuning characteristic. The chirp generator, implemented in a 28-nm CMOS process, dissipates 21 mW and generates sawtooth and triangular chirp frequency modulations with slope up to 680 MHz/ μ s and bandwidth up to 680 MHz, while keeping the rms frequency error below 150 kHz and the phase noise at 1-MHz offset at −116.5 dBc/Hz.
A 10-GHz Digital-PLL-Based Chirp Generator With Parabolic Non-Uniform Digital Predistortion for FMCW Radars
Tesolin, Francesco;Dartizio, Simone M.;Castoro, Giacomo;Buccoleri, Francesco;Rossoni, Michele;Cherniak, Dmytro;Samori, Carlo;Lacaita, Andrea L.;Levantino, Salvatore
2024-01-01
Abstract
This article describes a 10-GHz chirp generator for frequency-modulated continuous-wave (FMCW) radars, that is based on a digital PLL (DPLL) with a two-point injection of the modulation signal. A new digital predistortion (DPD) algorithm is introduced that is specifically tailored to mitigate the impact of the nonlinear non-smooth tuning curve of a digitally controlled oscillator (DCO) optimized for a low phase noise. The algorithm estimates in the background a non-uniform piecewise parabolic (PWP) interpolation of the digital inverse of the DCO tuning curve, using an adaptive set of non-uniformly distributed breakpoints. The breakpoints are automatically placed at the corner points of the tuning characteristic. The chirp generator, implemented in a 28-nm CMOS process, dissipates 21 mW and generates sawtooth and triangular chirp frequency modulations with slope up to 680 MHz/ μ s and bandwidth up to 680 MHz, while keeping the rms frequency error below 150 kHz and the phase noise at 1-MHz offset at −116.5 dBc/Hz.File | Dimensione | Formato | |
---|---|---|---|
A_10-GHz_Digital-PLL-Based_Chirp_Generator_With_Parabolic_Non-Uniform_Digital_Predistortion_for_FMCW_Radars.pdf
Accesso riservato
Descrizione: Early view
:
Publisher’s version
Dimensione
4.18 MB
Formato
Adobe PDF
|
4.18 MB | Adobe PDF | Visualizza/Apri |
A_10-GHz_Digital-PLL-Based_Chirp_Generator_With_Parabolic_Non-Uniform_Digital_Predistortion_for_FMCW_Radars.pdf
Accesso riservato
Descrizione: Paper
:
Publisher’s version
Dimensione
4.1 MB
Formato
Adobe PDF
|
4.1 MB | Adobe PDF | Visualizza/Apri |
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.