| Title |
Design of High Gain-suppression Low-noise Amplifier based on Self-biasing Adaptive Filter for Nonlinear-detection Radar Application |
| Authors |
우규식(Kyusik Woo) ; 서철헌(Chulhun Seo) |
| DOI |
https://doi.org/10.5573/ieie.2024.61.11.158 |
| Keywords |
Nonlinear-detection; RF-DC harvesting; Gain suppression; Self-biasing adaptive filter (SBAF); Low-noise amplifier (LNA) |
| Abstract |
This paper proposes a design methodology for a high gain-suppression low-noise amplifier (LNA) based on a self-biasing adaptive filter (SBAF) for nonlinear detection radar applications. The proposed LNA employs a SBAF, which consists of a frequency splitter network, an adaptive biasing rectifier, and an active resonance filter. The SBAF mechanism operates by first harvesting the transmit band signal through the frequency splitter network and converting it into DC power via the adaptive biasing rectifier. This converted bias is then dynamically adjusted according to the input signal and applied to the active resonance filter, enhancing the filter's Q-factor and significantly suppressing spurious signals. Simulation results demonstrate that the proposed LNA achieves an input reflection coefficient () of -13.2 dB at 3.1 GHz (transmit band, ) and -19.1 dB at 6.2 GHz (receiver band, ). The gain () is 15.9 dB at 6.2 GHz, while the gain at 3.1 GHz is as low as -41.1 dB, confirming the LNA's suitability for nonlinear detection radar applications. Additionally, the LNA suppresses the fourth harmonic () by more than 15 dB, improves the input third-order intercept point (IIP3) by 9.2 dB, and achieves a low noise figure of 1.22 dB, as verified by simulation. |