The increasing number of frequencies available for GNSS Navigation has a direct impact on the complexity of the Radio Frequency (RF) stage of the receivers. Though several studies already discussed possible multi-frequency architectures for mass market applications, no one addressed the specific needs of demanding high end applications, such safety of life certified receivers used in commercial aviation or crypto receivers used in governmental avionics. In order to answer this challenge, Thales Avionics, European leader on these markets, launched the study and the development of a new generation of a high performance, fully integrated, RF front-end chip for down-conversion and amplification of GNSS signals, called ARAMIS (Analogue Radionavigation Asic for Multiconstellation Signals). The architecture choice and the design of this chip has been entrusted to the design center of Thales Systemes Aeroportes Elancourt (France) to benefit of its expertise in this domain. The ARAMIS is a near-zero IF architecture, with an onchip Low Noise Amplifier (LNA), local oscillator, one down-conversion IF stage, a gain controlled amplifier, an on chip IF low pass filter and an Analog-to-Digital Converter (ADC). The chip embeds a RF test signal to check the RF chain. The paper discusses technical solutions that were chosen to cope with the main challenges of this development, such as the ability to process all services and signals and to withstand severe in and out band interference keeping volume and power as low as possible.
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