Analytical Model of High-Frequency Noise of Schottky-Barrier Frequency Multipliers

Abstract

An analytical model of the high-frequency noise of frequency multipliers based on Schottky-barrier diodes (SBD) operating in series with a parallel resonant circuit under large-signal conditions is developed. Such a model, on one hand, takes into account the main intrinsic features of the SBD noise related to shot-noise, returning carriers, plasma resonance at n+n homojunctions, and, on the other hand, it incorporates the SBD noise spectrum modifications induced by the output resonant circuit. It is shown that the SBD embedding into an external circuit can produce the appearance of an extra noise due to up-down conversion of the fluctuations of the voltage drop between the SBD terminals originated by a periodic modulation of the varactor capacitance by the pumping signal.

High-frequency voltage noise of nanometric Schottky-barrier diodes and heterostructure barrier varactor in cyclostationary conditions

“…(6) and (7). The first order iteration of the voltage noise exhibits a series of resonance peaks at frequencies ω=ω res +nω 0 (displacement current S 0 U d U d (ω − ω n )) compared to the zeroth order approximation when the spectrum presents one resonance peak in the third order of circuit harmonics ω res =3ω 0 (n = 1, 2, 3.... for the SBD structure) [4]. Figure 8 presents the comparison of the spectral densities of voltage fluctuations between the SBD and the HBV calculated at the first order S 1 according to Eq.…”

“…The intrinsic noise of the SBD or HBV is described by the current fluctuations δj with spectral density S ii (ω). The current flowing through the diode depends on δj by the approximation [4]:…”

“…[4,5] the equations describing the fluctuations of the voltage drop between the diode terminals, δU d , are obtained by linearization of the circuit equations of the equivalent scheme presented in Fig. 2 and using equation (2).…”