Frequency translation method for low frequency variable gain amplification and filtering

摘要

This thesis discusses an innovative solution to an industry challenge. A frequency translation method is designed to shift low frequency signals to intermediate frequencies in order to utilize higher-frequency components. This solution, appropriate for applications involving 1-10MHz signals, can provide continuously variable gain and filtering at little cost in dynamic performance. The working system converts the low frequency signals up to the 70MHz band to achieve up to 28dB attenuation and 60-86MHz variable filtering. A Single Side Band system has a Signal-to-Noise Ratio (SNR) of 71dB with a 73dB SNR Analog-to-Digital Converter (ADC), 44 dB Output Third-Order Intercept Point (OIP3), and a Noise Figure (NF) of 14dB. Ultrasound and other applications in the 1-10MHz range benefit greatly from this upconversion scheme.