International audienceThis paper presents and investigates a broadband sounding rocket antenna developed for dual-band data transmission of telemetric and payload systems. This single-element antenna permits the use of both the well-established 869.4-869.65 MHz and 2.4-2.4835 GHz frequency bands available in Europe to implement a redundant transmission of telemetric and tracking data desired for reliability. Furthermore, the available spectrum in the upper band offers a high-speed wireless link for transmitting payload data. To preserve the mechanical integrity and aerodynamics of rocket, the antenna is integrated in its nose cone. The proposed low-cost and low-weight structure is based on PCB (Printed Circuit Board) pieces assembled in a LEGO-like manner to form a broadband 3-Dimentional (3-D) bi-conical antenna, which is fed by a diplexer integrated in its base. A prototype has been fabricated, and validated using a reduced-length fuselage in a near-field measurement system

This article reports the design of a switchable low‐noise power amplifier (LNPA) intended for an active backscatter tag used in microwave localization and positioning applications. Due to system specifications, the backscattering transponder requires an amplifier having both low‐noise and high‐output power characteristics at the same time. Low‐noise amplifier and PA design considerations are both taken into account to realize a single structure achieving the required performances. The proposed LNPA is operating in the frequency range of 4.5–5.8 GHz. It achieves a gain of 21 dB with a ripple of ±1 dB, a noise figure of less than 2.5 dB, and an output compression point at −1 dB of 11 dBm over the operational bandwidth. This structure can be switched on and off by a control signal to modulate the tag radar cross section and enable distance measurement. A packaged prototype of the LNPA was fabricated and measured. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1251–1255, 2014

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