TY - GEN
T1 - A multi-channel ΣΔ modulator for subband digital predistortion with LTE signals
AU - Tchambake, Kelly
AU - Pham, Dang Kien Germain
AU - Jabbour, Chadi
AU - Desgreys, Patricia
AU - Loumeau, Patrick
N1 - Publisher Copyright:
© 2016 IEEE.
PY - 2016/10/20
Y1 - 2016/10/20
N2 - With the increasing bandwidth of communication signals, the challenges on the feedback path used for digital predistortion (DPD) of power amplifiers are getting significantly stringent. A subband approach has been recently proposed by the authors in order to relax the design constraints on the feedback path ADC. This paper presents a new step toward a practical implementation of the concept with LTE signals. A continuous-time multi-channel modulator is proposed to address wider bandwidths and sizing choices are discussed with simulation results. Some nonlinear effects of the feedback path such as I/Q imbalance, pure nonlinearity and quantization are simulated to define high level design parameters. Results show that for a distorted signal with 30 dB ACPR, 60 dB SNR is sufficient for the principal subband and 22 dB SNR is required for the adjacent subbands to perform as good as an ideal fullband DPD. Continuous-time simulation using a 2-4-4 configuration of the zero IF MSNBC with 4-bit quantizers achieves the required subband SNRs.
AB - With the increasing bandwidth of communication signals, the challenges on the feedback path used for digital predistortion (DPD) of power amplifiers are getting significantly stringent. A subband approach has been recently proposed by the authors in order to relax the design constraints on the feedback path ADC. This paper presents a new step toward a practical implementation of the concept with LTE signals. A continuous-time multi-channel modulator is proposed to address wider bandwidths and sizing choices are discussed with simulation results. Some nonlinear effects of the feedback path such as I/Q imbalance, pure nonlinearity and quantization are simulated to define high level design parameters. Results show that for a distorted signal with 30 dB ACPR, 60 dB SNR is sufficient for the principal subband and 22 dB SNR is required for the adjacent subbands to perform as good as an ideal fullband DPD. Continuous-time simulation using a 2-4-4 configuration of the zero IF MSNBC with 4-bit quantizers achieves the required subband SNRs.
UR - https://www.scopus.com/pages/publications/84998813251
U2 - 10.1109/NEWCAS.2016.7604802
DO - 10.1109/NEWCAS.2016.7604802
M3 - Conference contribution
AN - SCOPUS:84998813251
T3 - 14th IEEE International NEWCAS Conference, NEWCAS 2016
BT - 14th IEEE International NEWCAS Conference, NEWCAS 2016
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 14th IEEE International NEWCAS Conference, NEWCAS 2016
Y2 - 26 June 2016 through 29 June 2016
ER -