Large-dynamic ultra-wideband digital instantaneous frequency measurement method

Abstract

The invention discloses a large-dynamic ultra-wideband digital instantaneous frequency measurement method. The method adopts a radio frequency division technology and is combined with a channelized digital frequency measurement method, so that the covered frequency band is wide, the interception probability is high, and the high frequency resolution can be kept. The method selects 32 paths of digital channelization, so that the frequency measurement delay is ensured not to exceed 1 microsecond and the frequency measurement precision is within the range of 1 MHz. A radio frequency division module carries out three-stage amplification and equalization on an input 1-18 GHz radio frequency signal firstly, so that the input amplitude dynamic range is compressed through the design, and the dynamic range of the input signal is -45 dBm to 0 dBm, and the dynamic range is compressed to -5 dBm to 0 dBm after multi-stage amplification and equalization; and meanwhile, the deterioration of a signal-to-noise ratio is reduced; and furthermore, the amplitude flatness of 1 to 18 GHz of an ultra-wideband signal is ensured, so that the power of full-band signals sent to a frequency divider is within the normal working range of the frequency divider.

Description

technical field [0001] The invention relates to the fields of electronic reconnaissance and electronic countermeasures, in particular to a method for instantaneous frequency measurement. Background technique [0002] After decades of development, instantaneous frequency measurement technology has become very mature in theory and technology, and plays a very important role in the fields of electronic reconnaissance and electronic countermeasures. In an ideal, relatively simple electronic environment, any kind of instantaneous frequency measurement receiver will work very well. However, with the continuous advancement of radar technology, the form of radar signals has undergone great changes. Most radars have adopted frequency-agile technology. At the same time, the use environment has also undergone great changes. The electromagnetic environment faced by the receiver is becoming more and more complex. , At this time, a higher-performance instantaneous frequency measurement m...

AI Technical Summary

Problems solved by technology

The digital frequency measurement receiver is to directly perform AD conversion and digital storage on the input signal, and then perform digital signal processing in the FPGA. However, due to the limitation of the working speed of the digital circuit, it is not yet possible to directly perform the AD conversion and data storage of the radio frequency signal. , so the instantaneous bandwidth and the frequency measurement range are greatly limited. At present, the frequency converter is generally used to convert it to a certain baseband signal for processing, but this method not only increases the difficulty of RF circuit design, but also prolongs the frequency measurement time.

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