DESIGN OF AN FPGA BASED MULTI-FEATURE SPECTRUM ANALYZER

Yusuf Ayuba; Peter Dibal; Ngene Christopher Umerah; Okpor James

doi:10.4314/njt.2026.3713

Authors

Yusuf Ayuba Department of Computer Engineering, University of Maiduguri, NIGERIA.
Peter Dibal Department of Computer Engineering, University of Maiduguri, NIGERIA.
Ngene Christopher Umerah Department of Computer Engineering, University of Maiduguri, NIGERIA.
Okpor James Department of Computer Engineering, Federal University Wukari, Taraba, NIGERIA.

DOI:

https://doi.org/10.4314/njt.2026.3713

Keywords:

Spectrum Analyzer, Very High Speed Integrated Circuit Hardware Description Language (VHDL), Spectrum, Fast Fourier Transform (FFT)

Abstract

A spectrum analyzer is a device that plays central roles in many signal processing, machine monitoring, and diagnostics applications. It is used in evaluating the performance or functionality of a system through the analysis of the spectrum features of the signals from the system under observation. In this paper, a spectrum analyzer (SA) was designed for implementation on a field programmable gate array (FPGA); the SA was designed to output four important signal spectrum features- frequency, amplitude, phase, and power. The design approach in this work involved the design of an architecture for the SA, and coding implementation and verification using a combination of a high level synthesis (HLS) based on C language, and register-transfer-level (RTL) based on very high speed integrated circuits hardware description language (VHDL). The performance of the design obtained via simulation showed for the real signal, a root mean squared (RMSE) value of 4.86857e-4 when compared a MATLAB equivalent model. Similarly for the imaginary signal, an RMSE value of 3.3538e-1 was obtained. The performance for the frequency spectrum showed device (number of hardware components) utilization value of 897 with RMSE value of 0.0. The RMSE value implies that there is no error between the value from the MATLAB model of the spectrum extractor subsystem and the FPGA-based design in this work. Another reason for an RMSE value of 0.0 is that the Euclidean distance between two consecutive elements is constant in the set that represents the frequency index. For the amplitude spectrum, device utilization performance yielded a value of 46,286 with an RMSE value of 3.2e-6 when compared the equivalent MATLAB model. Similarly, the power spectrum device utilization performance yielded a value of 46, 762, and an RMSE value of 2.27237e-4 when compared with the equivalent MATLAB model. Performance comparison was also made with related works; it was observed that the design in this work showed significant improvement in terms of accuracy and resource utilization.

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