2 results about "Instantaneous frequency measurement" patented technology

This invention discloses an ultra-wideband, high-precision instantaneous frequency measurement circuit and method, belonging to the field of frequency measurement technology. It includes a power divider group, multiple frequency measurement channels, an analog switch group, an SP3T switch, a direct digital frequency synthesizer (DDS), and an FPGA. The input RF signal is divided into four channels by the power divider group, corresponding to four frequency measurement channels. Each frequency measurement channel corresponds to a different frequency range, and the channels operate in parallel. Each channel signal is output as an LVTTL level to the FPGA after passing through a detector and comparator. The FPGA determines the frequency range based on the level combination and controls the analog switch and SP3T to select the corresponding channel. The frequency of the signal generated by the DDS is measured by the FPGA, and the input RF signal frequency is calculated inversely based on the division ratio and frequency control word. This invention achieves DC-20GHz ultra-wideband frequency measurement. The measurement speed depends on the DDS frequency switching speed. After the measurement is completed, the power to the divider is turned off to eliminate spurious interference. The circuit structure is simple and low-cost.