Selective Intermodulation Compensation in a Multi-Stage Digital Predistorter for Nonlinear Multi-Band Power Amplifiers

This paper presents a technique for suppressing the intermodulation distortion caused by nonlinear multi-band power amplifiers with minimal modeling complexity. The technique is based on generating a narrowband static predistorter for the power amplifier. Then, the intended multi-band signals are resampled and shifted into their representative carrier frequencies before applying the static predistorter in order to accommodate the intermodulation distortion products produced by the nonlinearity. Since the resampling frequency may be high, a study is presented, using filtering techniques to represent low-bandwidth transmitter schemes, to show the accuracy of the intermodulation distortion suppression. Results are presented for the proposed predistorter for two amplifiers: one in a tri-band carrier aggregated LTE scenario in the sub 3 GHz frequencies and another in the millimeter-wave band, demonstrating the effectiveness of reducing the intermodulation products using 5G signals.

[1]  Joseph R. Cavallaro,et al.  Sub-band digital predistortion for noncontiguous transmissions: Algorithm development and real-time prototype implementation , 2015, 2015 49th Asilomar Conference on Signals, Systems and Computers.

[2]  Zhijian Xie,et al.  A Generalized Architecture for the Frequency- Selective Digital Predistortion Linearization Technique , 2013, IEEE Transactions on Microwave Theory and Techniques.

[3]  Fadhel M. Ghannouchi,et al.  Augmented Dual-Band Digital Predistorter for Reducing Cross-Band Intermodulation Distortion Using Predictive Injection Technique , 2016, IEEE Transactions on Microwave Theory and Techniques.

[4]  Chao Yu,et al.  Digital Compensation for Transmitter Leakage in Non-Contiguous Carrier Aggregation Applications With FPGA Implementation , 2015, IEEE Transactions on Microwave Theory and Techniques.

[5]  Fadhel M. Ghannouchi,et al.  A Digital Predistortion System With Extended Correction Bandwidth With Application to LTE-A Nonlinear Power Amplifiers , 2014, IEEE Transactions on Circuits and Systems I: Regular Papers.

[6]  Joseph R. Cavallaro,et al.  Low-Complexity Subband Digital Predistortion for Spurious Emission Suppression in Noncontiguous Spectrum Access , 2016, IEEE Transactions on Microwave Theory and Techniques.

[7]  Chao Yu,et al.  A band-limited 2-D digital predistorter for concurrent dual-band RF transmitters , 2014, 2014 IEEE International Wireless Symposium (IWS 2014).

[8]  Fadhel M. Ghannouchi,et al.  Extending the Characterization Bandwidth of Dynamic Nonlinear Transmitters With Application to Digital Predistortion , 2016, IEEE Transactions on Microwave Theory and Techniques.

[9]  F.M. Ghannouchi,et al.  Deembedding static nonlinearities and accurately identifying and modeling memory effects in wide-band RF transmitters , 2005, IEEE Transactions on Microwave Theory and Techniques.

[10]  Fadhel M. Ghannouchi,et al.  Channel-Selective Multi-Cell Digital Predistorter for Multi-Carrier Transmitters , 2012, IEEE Transactions on Communications.

[11]  F.M. Ghannouchi,et al.  Behavioral modeling and predistortion , 2009, IEEE Microwave Magazine.

[12]  Joseph R. Cavallaro,et al.  Low-complexity digital predistortion for reducing power amplifier spurious emissions in spectrally-agile flexible radio , 2014, 2014 9th International Conference on Cognitive Radio Oriented Wireless Networks and Communications (CROWNCOM).

[13]  Fadhel M. Ghannouchi,et al.  A multi-stage concurrent dual-band DPD architecture for closely spaced carriers using a low bandwidth feedback loop , 2016, 2016 IEEE MTT-S International Microwave Symposium (IMS).

[14]  Patrick Roblin,et al.  Efficient Least-Squares 2-D-Cubic Spline for Concurrent Dual-Band Systems , 2015, IEEE Transactions on Microwave Theory and Techniques.

[15]  A. Kwan,et al.  Subsampling Feedback Loop Applicable to Concurrent Dual-Band Linearization Architecture , 2012, IEEE Transactions on Microwave Theory and Techniques.

[16]  Fadhel M. Ghannouchi,et al.  Reduced-complexity power amplifier linearization for carrier aggregation mobile transceivers , 2014, 2014 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP).

[17]  Anding Zhu,et al.  Modeling and suppression of transmitter leakage in concurrent dual-band transceivers with carrier aggregation , 2015, 2015 IEEE MTT-S International Microwave Symposium.

[18]  Fadhel M. Ghannouchi,et al.  Bandwidth and Power Scalable Digital Predistorter for Compensating Dynamic Distortions in RF Power Amplifiers , 2013, IEEE Transactions on Broadcasting.

[19]  Peter M. Asbeck,et al.  Digital cancellation technique to mitigate receiver desensitization in cellular handsets operating in carrier aggregation mode with multiple uplinks and multiple downlinks , 2015, 2015 IEEE Radio and Wireless Symposium (RWS).

[20]  Tao Jiang,et al.  PAPR Reduction of OFDM Signals Using Partial Transmit Sequences With Low Computational Complexity , 2007, IEEE Transactions on Broadcasting.

[21]  F. M. Ghannouchi,et al.  2-D Digital Predistortion (2-D-DPD) Architecture for Concurrent Dual-Band Transmitters , 2011, IEEE Transactions on Microwave Theory and Techniques.

[22]  Peter M. Asbeck,et al.  Concurrent Dual-Band Digital Predistortion With a Single Feedback Loop , 2015, IEEE Transactions on Microwave Theory and Techniques.