Roger D. Pollard

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—The rectangular dielectric waveguide (RDWG) technique has been developed for the determination of the dielectric constant of materials from effective refractive index measurements in the Q and W bands. This paper describes the use of an optimization method in conjunction with the RDWG technique for the determination of both the dielectric constant and loss(More)
—Device mismatch seriously degrades accuracy in noise figure characterization. The suitability of corrections to the gain definitions for a more precise noise figure evaluation for mismatched devices is investigated and compared to classical techniques. The effects of device mismatch on the noise figure of the noise-meter receiver and its impact on the(More)
— This paper presents an extension to the rectangular dielectric waveguide technique to obtain the permittivity of samples iteratively from the effective refractive index measurements by using the solution of the wave equation. The effective refractive index is presented for several samples in the 33 GHz to 50 GHz frequency range. The method is very fast(More)
Multi-stage high power amplifiers require more accurate behavioural models to provide a better description of memory effects and highly nonlinear characteristics than memoryless models based on single-tone transfer characteristics. This is achieved using measured two-tone transfer characteristics of the amplitude and phase of the fundamental, IM3 and IM5(More)
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