Digital down conversion method based on quadratic symmetric filtering
A digital down-conversion and symmetrical technology, applied in the field of electronic information, can solve the problems of high filter order requirements, high hardware cost, and long system delay
Active Publication Date: 2019-02-12
西安恒盛安信智能技术有限公司
View PDF8 Cites 0 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
[0004] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art, and provide a digital down-conversion method based on secondary symmetric filtering. High, resulting in long system delay, high hardware consumption, high cost, etc.
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment
[0173] A simulation test has been carried out with regard to the digital down-conversion method based on secondary symmetric filtering of the present invention, and the specific process is as follows:
[0174] 1. Simulation conditions
[0175] In Matlab2008, a chirp signal with a sampling frequency of 100MH and a bandwidth B of 12MHz is generated, and the local chirp signal (n represents an integer from 0 to 1799), see image 3 , (a) is the time-domain diagram of the real part of the local chirp signal, and (b) is the time-domain diagram of the imaginary part of the local chirp signal.
[0176] Move it to the intermediate frequency of 125MHz according to the method of spectrum shifting, and take the real part to obtain the input signal x(n) of step 1, and the analytical formula of x(n) is expressed as:
[0177]
[0178] Here real(.) means to take the real part of the signal, and the spectrum of x(n) can be found in Figure 4 .
[0179] Simulation case 1: ideal state, w...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More PUM
Login to View More Abstract
The present invention discloses a digital down conversion method based on quadratic symmetric filtering, and includes: mixing digital signals to obtain an in-phase channel signal and a quadrature channel signal; performing digital symmetric filtering on the in-phase channel signal and the quadrature channel signal, to filter out high frequency signal components, and obtaining an in-phase channel digital filtering signal and a quadrature channel digital filtering signal; extracting the in-phase channel digital filtering signal and the quadrature channel digital filtering signal to obtain an in-phase channel extraction signal and a quadrature channel extraction signal; and performing digital symmetric frequency division filtering on the in-phase channel extraction signal and the quadrature channel extraction signal to obtain an in-phase channel baseband signal and a quadrature channel baseband signal. In a process of converting signals from digital intermediate frequency to baseband, a processing delay is greatly reduced, the quantity of multiplication operations in the process is greatly reduced, hardware development costs are greatly reduced, and hardware consumption is reduced during development, which is beneficial to system stability.
Description
technical field [0001] The invention belongs to the technical field of electronic information, and relates to a digital down-conversion method based on secondary symmetric filtering. Background technique [0002] In the field of electronic information, digital signal processing occupies a very important position. The digital signal that undergoes analog-to-digital conversion through the analog front end is usually a digital intermediate frequency signal that has been digitally sampled, and the effective information in it cannot be directly extracted. The digital intermediate frequency signal must be converted into a baseband signal for subsequent information extraction. Therefore, the digital down-conversion technology is completing such work, effectively processing the input signal, and converting it into the required baseband signal after processing. [0003] For the digital down-conversion method, the technical difficulty encountered is that in the process of finite puls...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More Application Information
Patent Timeline
Login to View More Patent Type & Authority Applications(China)
IPC IPC(8): H03H17/02
CPCH03H17/02
Inventor 李彦涛杨永锋贾丹
Owner 西安恒盛安信智能技术有限公司