High two-signal dynamic range and accurate frequency measurement for close frequency separation wideband digital receiver using adaptive gain control and adaptive thresholding

• Published in: Integration (Amsterdam) Vol. 72; pp. 72 - 81
• Main Authors: Liu, Feiran, Chen, Chien-In Henry
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.05.2020; Elsevier BV
• Subjects: Adaptive control; Algorithms; Amplification; Analog to digital conversion; Analog to digital converters; Broadband; Carrier frequencies; Dynamic range; Electronic warfare; Electronic-warfare (EW); Fast Fourier Transform (FFT); Fast Fourier transformations; Fourier transforms; Frequency measurement; Gain; Multiple-signal detection; Radar detection; Radar systems; Real time; Receivers; Two-signal dynamic range; Wideband digital receiver; Wideband digital receiver; Two-signal dynamic range; Fast Fourier Transform (FFT); Electronic-warfare (EW); Multiple-signal detection
• ISSN: 0167-9260; 1872-7522
• DOI: 10.1016/j.vlsi.2019.11.012

In electronic-warfare (EW) receiver applications, real-time measurement of the radar signals' carrier frequencies is mandatory and considered to be one of the most important radar parameters. Accurate frequency detection can be used to sort and deinterleave signals in a dense signal environment where multiple signals arrive simultaneously presenting severe problems unless they can be differentiated appropriately. Researchers and engineers are actively looking for new algorithms for high resolution wideband receivers with easier implementation. This paper presents an adaptive gain control and dynamic thresholding wideband digital receiver to accurately detect two simultaneous high dynamic range signals, even when their signal frequencies are very close. The proposed fast Fourier transform (FFT) based receiver examines incoming signal characteristics and provides real-time accomplishment of these tasks, by way of using an adaptive gain-control amplifier, a squarer, two analog-to-digital converters, and two FFT's. The wideband receiver offers high probability of intercept over wide instantaneous RF bandwidths, high dynamic ranges and sensitivity. Two simultaneous signal accommodations and their characteristics are provided to demonstrate the improvements over presently used receivers in this field.