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Updated: Jul 7, 2026
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Published on: June 25, 2021
SAW device implementation of a weighted stepped chirp code signal for direct sequence spread spectrum communications
1Palm Bay, FL, USA. scarte02@harris.com
Summary
A new weighted stepped chirp code signal offers improved performance for direct sequence spread spectrum (DS/SS) systems. This novel signal provides better compression ratio and peak sidelobe levels than pseudonoise codes, with easier implementation than continuous wave chirps.
Area of Science:
- Electrical Engineering
- Signal Processing
- Communications Systems
Background:
- Direct Sequence Spread Spectrum (DS/SS) systems require efficient code signals for reliable communication.
- Pseudonoise (PN) codes and continuous wave (CW) chirps are common but have limitations in performance or implementation complexity.
Purpose of the Study:
- To introduce and evaluate a novel weighted stepped chirp code signal for DS/SS systems.
- To compare its performance against PN codes and CW chirps.
- To explore its implementation using Surface Acoustic Wave (SAW) devices.
Main Methods:
- Discretization of a continuous wave (CW) chirp using truncated cosine series functions.
- Implementation of the code signal on Surface Acoustic Wave (SAW) devices for signal generation and correlation.
- Experimental analysis of code length, weighting functions, and sampling effects on performance.
Main Results:
- The weighted stepped chirp code signal demonstrates superior compression ratio (CR) and peak sidelobe level (PSL) compared to PN codes of identical length.
- It achieves comparable CR and PSL to CW chirps with similar parameters.
- Experimental results validate predicted performance across various SAW device configurations.
Conclusions:
- The proposed weighted stepped chirp code signal offers a promising alternative for DS/SS communications.
- Its performance advantages and feasible implementation on SAW devices make it suitable for practical applications.
- Further research can optimize SAW device design for enhanced performance and reduced intersymbol interference.
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