A real-time generation method of broadband chirp signal based on fpga and dac

A technology of linear frequency modulation signal and generation method, applied in radio wave measurement systems, instruments, etc., can solve the problems of complex external memory hardware design, high FPGA timing risk, limited internal memory resources, etc., to reduce the processing clock rate and achieve breakthroughs The effect of limited memory resources and improved adaptability

Active Publication Date: 2020-04-10
XIAN INSTITUE OF SPACE RADIO TECH
View PDF3 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This method has problems such as limited internal memory resources, complex external memory hardware design, and high FPGA timing risks.

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 more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • A real-time generation method of broadband chirp signal based on fpga and dac
  • A real-time generation method of broadband chirp signal based on fpga and dac
  • A real-time generation method of broadband chirp signal based on fpga and dac

Examples

Experimental program
Comparison scheme
Effect test

Embodiment

[0103] Suppose the center frequency f of the broadband chirp signal to be generated is 0 =600MHz, bandwidth B=200MHz, time width τ=50us.

[0104] The steps for generating a broadband chirp signal are as follows:

[0105] (a1) Determine parameters such as the center frequency, time width, bandwidth, and duty cycle of the broadband chirp signal. Design and realize the center frequency f of the broadband chirp signal 0 =600MHz, bandwidth B=200MHz, time width τ=50us, duty cycle 50%, minimum signal frequency f L =500MHz, the highest frequency f H =700MHz.

[0106] (a2) Determine the processing clock rate of the DAC chip in combination with the parameters of the broadband chirp signal and the sampling theorem of the digital signal.

[0107] According to the digital bandpass sampling theorem DAC operating frequency n takes 1, f 0 =600MHz, calculate f DAC is 800MHz, and satisfies f DAC ≥2(f H -f L ), and finally use the waveform of the second Nyquist domain output by the D...

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

No PUM Login to view more

Abstract

The invention provides a method for generating broadband chirp signals on a real-time basis based on FPGA and DAC. The method includes the steps of determining the parameters of the broadband chirp signals to be generated, determining the processing clock rate of a DAC chip, determining the route number for real-time parallel processing of chirp signals by FPGA and clock rate according to the processing clock rate of the DAC chip and the processing capability of an FPGA chip, and determining the angle quantification bit number of FPGA real-time calculation, calculating the real-time angle of each path of chirp signal through an FPGA adder, obtaining the cosine value of the real-time angle of each path of chirp signal, and the FPGA controlling the DAC chip to output broadband chirp signals. The upper limit of the signal bandwidth and signal frequency is not restricted by sampling frequency of a device, the bottleneck that FPGA internal memory resource is constrained in a conventional method is overcome, no external memory is needed, sequential risk of FPGA program design is reduced, and design reliability is improved.

Description

technical field [0001] The invention relates to a real-time generation method of a broadband chirp signal based on FPGA and DAC, and belongs to the field of radar broadband chirp signal generation. Background technique [0002] Broadband chirp signals are widely used in stand-alone remote sensing satellite signal processing. In remote sensing loads such as ground detection radar, spaceborne SAR, and scatterometer, the performance of broadband chirp signals is a very important indicator. Broadband chirps have significant advantages over narrowband chirps. The broadband chirp signal increases the information capacity of the system, provides more information about the frequency domain of the target, provides more basis for target identification, and reduces the impact of multipath effects. At the same time, the broadband chirp signal can enhance the anti-jamming ability of the radar. Effectively detect objects from clutter. The radar detection distance is related to the power...

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
no application Login to view more
Patent Type & Authority Patents(China)
IPC IPC(8): G01S7/282
CPCG01S7/282
Inventor 贾建超李彬孙嘉郭语张爱军李拴劳
Owner XIAN INSTITUE OF SPACE RADIO TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products