High-Order Harmonic Mixing based Ultra-Low-Cost L-Band GNSS Signal Generator

This paper presents an ultra-low-cost L-band spread spectrum GNSS signal generator. Conventional SDR-based GNSS signal generators are expensive and they require a standalone computer to generate the baseband signal. The pro-posed ultra-low-cost GNSS signal generator adopts high-order harmonic mixing techniques to greatly simplify the LO chain design and uses an I2S peripheral on the micro controller to gen-erate the spread spectrum signal stream. Due to the extremely lean architecture, the entire system contains only 3 active devices and is fairly low-cost. A novel bit operation-based 1-bit quantization method is proposed to generate the required bitstream.