Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Orthogonal multi-carrier Doppler estimation calculation method based on channel sparsity detection

A technology of Doppler estimation and calculation method, which is applied in the field of ultra-wideband orthogonal multi-carrier mobile communication, and can solve the problems of reducing the communication performance of OFDM systems, inter-carrier interference, etc.

Active Publication Date: 2021-12-10
SUZHOU SOUNDTECH OCEANIC INSTR
View PDF9 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] In order to solve the problem that underwater acoustic communication is sensitive to the Doppler effect in the prior art, causing inter-carrier interference and seriously reducing the communication performance of the OFDM system, the present invention provides an orthogonal multi-carrier Doppler based on channel sparsity detection. Le estimation method

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
  • Orthogonal multi-carrier Doppler estimation calculation method based on channel sparsity detection
  • Orthogonal multi-carrier Doppler estimation calculation method based on channel sparsity detection
  • Orthogonal multi-carrier Doppler estimation calculation method based on channel sparsity detection

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0115] In order to verify the feasibility and reliability of the calculation method in the present invention in the environment of ice-water mixed areas in middle and high latitude sea areas, this paper uses matlab software to carry out Monte Carlo simulation on the calculation method. The simulated channel adopts the sub-ice channel response measured in the 7th Arctic scientific expedition in 2016, the communication distance is 6500m, and the average sea depth is 150m. as attached Figure 3-4 As shown, it can be seen that due to the influence of ice floes on the surface of polar seas, the channel multipath is densely distributed and the multipath energy is strong. At the same time, affected by the Arctic Ocean bottom reflection, the maximum multipath delay reaches 250ms.

[0116] The system adopts OFDM system simulation parameters, in which, the FFT length is 8192, the sampling rate is 48kHz, the communication frequency band B is 4-8kHz, Δf is 5.85Hz, and the comb pilot occup...

Embodiment 2

[0124] On January 30, 2018, the sea trial test was carried out in the offshore of Dandong. The water area where the test is located is 22 nautical miles south of Dandong Port. The water area where the test is located is open, with an average sea depth of 18 meters and a large amount of floating ice on the surface of the sea. During the test, the signal receiving ship was anchored at sea, and the receiving transducer was hoisted at 10 meters underwater. The signal sending ship is located 1.5km north of the receiving ship. The ship drifts slowly with the current, and the sending transducer is hoisted at 8 meters underwater. During the communication process, the coding method and parameter configuration adopted by the system are consistent with the first embodiment, and the communication rate is 2.4 kbps. A total of 9 frames of signals were received during the test.

[0125] as attached Figure 8-10 As shown, the sound velocity below the water surface 5 meters presents a weak...

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 present invention provides an orthogonal multi-carrier Doppler estimation calculation method based on channel sparsity detection, which includes the following steps: S1, acquiring OFDM signals passing through the underwater acoustic channel; S2, performing recalculation of different Doppler parameters on the received signals Sampling, obtaining demodulation pilot vector samples compensated by multiple Doppler search factors; S3, performing sparse channel reconstruction on each sample of the demodulation pilot vector, and calculating the channel time-domain impulse response after each sample is matched; S4 , select the Doppler search factor corresponding to the sample channel with the largest sparsity as the optimal compressed sensing resampling factor to obtain the Doppler estimation value. The present invention adopts the demodulation pilot vector z of the algorithm i,γ It is directly generated by FFT after Doppler factor compensation, regardless of the interpolation effect, z i,γ There is no deviation; the smaller the step size of Doppler estimation accuracy and Doppler search compared with the prior art, the higher the accuracy of Doppler estimation in the present invention.

Description

technical field [0001] The invention relates to the field of ultra-wideband orthogonal multi-carrier mobile communication, in particular to an orthogonal multi-carrier Doppler estimation calculation method based on channel sparseness detection. Background technique [0002] Orthogonal frequency division multiplexing (OFDM) technology has the advantages of high data transmission rate and high spectrum efficiency, and has received more and more attention in the field of underwater acoustic communication. However, OFDM underwater acoustic communication is sensitive to the Doppler effect, and the Doppler frequency shift destroys the orthogonality between sub-carriers, causing inter-carrier interference, which seriously reduces the communication performance of OFDM systems. Due to the low surface temperature in the ice-water mixing area in middle and high latitude seas, a stable positive gradient sound velocity distribution is formed under the water surface, so the sound wave fre...

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): H04L25/02H04L27/26
CPCH04L25/022H04L27/2647H04L27/2656
Inventor 王巍钱斌毕坤
Owner SUZHOU SOUNDTECH OCEANIC INSTR
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com