Low-Complexity Harmonic Cancellation Scheme Based on Digital Multitone Mixing for Short-Wave Power Amplifier

In short-wave (SW) communication system, the harmonics of the power amplifier (PA), which may fall within the transmission range, are the principal consideration of harmonic interference. In the process of harmonic cancellation (HC), the number of sampling points always needs to be large enough when capturing multiple harmonics. It directly leads to the increase of modeling complexity. In order to solve this problem, this letter proposes a low-complexity HC scheme based on digital multitone mixing (DMTM), which uses multitone signals to mix harmonic signals into a narrow range for processing. The experimental results show that the multiple harmonics can be canceled to −69 dBc in the proposed HC scheme. Also, the complexity is only 3.3% and 1.7% of the full-band HC scheme when the carrier frequencies are 5 and 8 MHz.