Influence of Analog-To-Digital Conversion and Decimation Parameters on the Signal-To-Noise Ratio in the Radar Path
https://doi.org/10.32603/1993-8985-2021-24-6-38-50
Abstract
Introduction. The digital representation of received radar signals has provided a wide range of opportunities for their processing. However, the used hardware and software impose some limits on the number of bits and sampling rate of the signal at all conversion and processing stages. These limitations lead to a decrease in the signal-to-interference ratio due to quantization noise introduced by powerful components comprising the received signal (interfering reflections; active noise interference), as well as the attenuation of a low-power reflected signal represented by a limited number of bits. In practice, the amplitude of interfering reflections can exceed that of the signal reflected from the target by a factor of thousands.
Aim. In this connection, it is essential to take into account the effect of quantization noise on the signal-tointerference ratio.
Materials and methods. The article presents expressions for calculating the power and power spectral density (PSD) of quantization noise, which take into account the value of the least significant bit of an analog-to-digital converter (ADC) and the signal sampling rate. These expressions are verified by simulating 4-, 8- and 16-bit ADCs in the Mathcad environment.
Results. Expressions are derived for calculating the quantization noise PSD of interfering reflections, which allows the PSD to be taken into account in the signal-to-interference ratio at the output of the processing chain. In addition, a comparison of decimation options (by discarding and averaging samples) is performed drawing on the estimates of the noise PSD and the signal-to-noise ratio.
Conclusion. Recommendations regarding the ADC bit depth and sampling rate for the radar receiver are presented.
About the Authors
S. R. Heister
JSC "ALEVKURP"
Belarus
Belarus
Sergey R. Heister, Dr Sci. (Eng.) (2004), Professor (2006), Leading Researcher. The author of more than 150 scientific publications. Area of expertise: construction of radio engineering systems for various purposes; radar recognition; adaptive signal processing; radioelectronic protective measures.
1a Moscow St., Korolev Stan 223050
V. V. Kirichenko
JSC "ALEVKURP"
Belarus
Belarus
Valery V. Kirichenko, Senior Researcher. The author of more than 10 scientific publications. Area of expertise: formation and processing of radio signals; simulation of real processes and devices.
1a Moscow St., Korolev Stan 223050
References
1. Skolnik M. I. Radar Handbook, 3rd ed. NY, McGraw-Hill, 2008, 1328 p.
2. Barton D. K., Ward H. Handbook of Radar Measurement. N. J., Prentice-Hall, 1969, 426 p.
3. Barton D. K., Leonov S. A. Radar technology encyclopedia. Boston, Mass., Artech House, 1998, 511 р.
4. Barton D. K. Radar Equations for Modern Radar. Boston, Mass., Artech House, 2013, 428 p.
5. Fel'dman Yu. I., Mandurovskii I. A. Teoriya fluktuatsii lokatsionnykh signalov, otrazhennykh raspredelennymi tselyami [Theory of fluctuations of location signals reflected by distributed targets]. Ed. by Yu. I. Fel'dman. Moscow, Radio i svyaz', 1988, 272 p. (In Russ.)
6. Heister S. R. Adaptivnoe obnaruzhenie-raspoznavanie s selektsiei pomekh po spektral'nym portretam [Adaptive detection-recognition with interference selection based on spectral portraits]. Minsk, Voennaya akademiya RB, 2000, 172 p. (In Russ.)
7. Okhrimenko A. E. Osnovy radiolokatsii i radioelektronnoi bor'by. Ch. 1. Osnovy radiolokatsii [Fundamentals of radar and electronic warfare. Part 1. Fundamentals of Radar]. Moscow, Voenizdat, 1983, 456 p. (In Russ.)
8. Bennet W. R. Spectra of Quantized Signals. Bell System Tech. J. 1948, vol. 27, pp. 446–471.
9. Jenkins G., Watts D. Spectral Analysis and Its Applications. Holden-Day, San Francisco, 1968, p. 525.
10. Rabiner L., Gold B. Theory and Application of Digital Signal Processing. Prentice Hall Inc., Englewood Cliffs, N. J., 1975, 762 p.
11. Applications of Digital Signal Processing. Ed. by A. Oppenheim. Prentice Hall Inc., Englewood Cliffs, N. J., 1978, 499 p.
12. Gol'denberg L. M., Matyushkin B. D., Polyak M. N. Tsifrovaya obrabotka signalov: Spravochnik [Digital Signal Processing: Handbook]. Moscow, Radio i svyaz', 1985, 312 p. (In Russ.)
13. Oppenheim A., Schafer R. Discrete-Time Signal Processing. 3rd ed. NJ, Prentice Hall, 1999, 870 p.
14. Lyons R. G. Understanding Digital Signal Processing. NJ, Prentice Hall, 2001, 517 p.
15. Kester W. Analog-Digital Conversion. Norwood, Analog Devices, 2004.
Review
For citations:
Heister S.R., Kirichenko V.V. Influence of Analog-To-Digital Conversion and Decimation Parameters on the Signal-To-Noise Ratio in the Radar Path. Journal of the Russian Universities. Radioelectronics. 2021;24(6):38-50. (In Russ.) https://doi.org/10.32603/1993-8985-2021-24-6-38-50
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