System and method for measuring radio-frequency signal high-speed sweeping frequency spectrum based on digital local oscillator

Abstract

The invention relates to a system for measuring a radio-frequency signal high-speed sweeping frequency spectrum based on a digital local oscillator. The system comprises a radio frequency conversion unit, an intermediate frequency signal conditioning unit and a digital intermediate frequency signal processing and controlling unit which are sequentially connected in series. The digital intermediate frequency signal processing and controlling unit is provided with a digital scan synchronous control circuit module and a programmable digital oscillator, wherein the digital scan synchronous control circuit module is connected with an in-phase quadrature (IQ) signal shunt processing circuit module through the programmable digital oscillator, the digital scan synchronous control circuit module is connected with a first local oscillator device, a detector, or a fast fourier transform (FFT) convertor. The invention further relates to a method which is based on the system and achieves synchronous control for the scanning in high-speed sweeping frequency spectrum measurement. Due to the fact that the system and method for measuring radio-frequency signal high-speed sweeping frequency spectrum based on the digital local oscillator are adopted, scanning time is greatly shortened, local frequency accuracy in a scanning process is improved, circuit hardware is simplified, cost is reduced, working performance is stable and reliable, and range of application is wide.

Description

technical field [0001] The present invention relates to the field of spectrum analysis, in particular to the technical field of radio frequency signal spectrum measurement, in particular to a system and method for realizing high-speed frequency sweep spectrum measurement of broadband radio frequency signals based on digital local oscillators. Background technique [0002] Spectrum analysis can obtain unique information that cannot be obtained in time-domain measurement, such as harmonic components, spurious, intermodulation, noise sidebands, etc., and has become an irreplaceable important means in the field of signal measurement. The spectrum analyzer with swept frequency superheterodyne structure is widely used for its wide frequency band, large dynamic range, high sensitivity and high cost performance. With the development of software radio technology and large-scale integrated circuit technology, all-digital intermediate frequency technology High reliability, high precisi...

AI Technical Summary

Problems solved by technology

In order to meet this requirement, a large number of complex and precise circuit technologies must be used, such as fractional frequency division technology, ∑-△ modulation technology, API, DDS technology, etc., so that the complexity, cost, volume and power consumption of the equipment are all reduced. Greatly improved and reduced reliability

[0019] (2) Restricted by the stabilization time of the local oscillator and the response time of the intermediate frequency filter, the key parameter reflecting the measurement speed of the spectrum analyzer - the relatively long scan time affects the real-time performance of the measurement. In the measurement of some transient signals even fatal

There are many problems caused by analog signals, such as inaccurate scan time and poor frequency measurement accuracy caused by interference and nonlinearity, etc., which require related calibration processing in the later stage

Images