Chaotic Behavior in Receiver Front-End Limiters

Abstract

Abstract-A delay nonlinear differential equation is proposed to investigate the condition of the microwave chaotic behavior existing between the antenna and the front-end protection circuit of a receiver such as the radar front-end limiter circuit. This investigation concerns the case of intentional or unintentional signals applied to the antenna outside of its bandwidth.Bifurcation diagrams show that the chaotic behavior appears for antenna impedance up to 10 Ω and for amplitudes greater than 1.2 V. Electrical simulation results agree well with theoretical ones.

Electromagnetic Interference Impact on Front-End Receivers Outside the Antenna Bandwidth

“…k 0 = 2πf c −1 , J 0 is the Bessel function of the first kind of order zero and g(θ) defined as: Figure 1 depicts the real part R antenna versus frequency calculated from Z antenna . In [9], we have shown that the chaos appears for Z g ≤ 10 Ω. For each antenna, the value R antenna = 10 Ω is indicated in Figure 1 to Figure 4.…”

“…The equation proposed in [9] is used (Equation (1)) to study the chaos zones from bifurcation diagrams and the attractors. For each antenna, the impedance Z g which appears in Equation (1) is replaced by the real part of the antenna radiation impedance.…”

“…The bifurcation diagrams present the local maxima number of the voltage V D (t) versus the bifurcation parameters f and E g [9]. The local maxima number is represented on a color scale which ranges from dark blue (period-1) to dark red (chaos).…”

“…The doubling period has been observed in 'line-diode' circuits in the case of partial reflection [7]. A delay nonlinear differential equation has been proposed in [9] to study the possible generation of chaos in the front-end microwave limiter receivers. In this paper, we present theoretical and experimental investigations of chaos generation in the front-end receivers for different types of antenna, 2.45 GHz resonant frequency antennas (patch, monopole and loop antennas) and 8.2-12.4 GHz bandwidth horn antenna.…”

“…In this paper, we present theoretical and experimental investigations of chaos generation in the front-end receivers for different types of antenna, 2.45 GHz resonant frequency antennas (patch, monopole and loop antennas) and 8.2-12.4 GHz bandwidth horn antenna. For each antenna, theoretical and experimental bifurcation diagrams derived from delay nonlinear differential equation proposed in [9] are exploited to show the existence of the chaos. To the author knowledge, it is the first work which demonstrates the experimental chaos generation in the front-end receivers.…”