The analog predistortion (APD) is a compact solution for RF high power amplifier and Traveling wave tube linearization. The APD is easier to integrate inthe base station, repeaters due to the advantage of simplecircuitry, as well as when bandwidth increases the APD hasan advantage over DPD in terms of cost and power overhead. Therefore these features makes it a suitable candidate for upcoming 5G communication and satellite communication.
Analog predistorter linearizer
APD linearization results for a two LTE (5 MHz) signal with spacing of 100 MHz
We have developed and deployed distortion correction algorithm for RF High power amplifiers (SSPA/TWTA). This predistortion method requires the baseband access of the I/Q signals for modeling and distortion correction. The advantage of this method lies in terms of no extra hardware required at the user end, the performance can be achieved by just modifying the baseband algorithm which can be incorporated at the user end. Our method works upto 500 MHz bandwidth and distortion reduction >20 dB. Moreover we have also achieved good performance in the case of multiple-input and multiple-output (MIMO) DPD transmitters.
Spectrum of power amplifier before and after linearization