An integrated overlay architecture based multi-GNSS front-end

Abstract

This paper presents the overall architecture, first test structure implementations, and measurement results of an integrated GNSS front-end based on intentional path overlay. The front-end ASIC supports simultaneous multiband, multi-system GNSS reception of GPS L5 / Galileo E5 / GLONASS G3 and GPS L1 / Galileo E1 / GLONASS G1 signals with up to 52 MHz bandwidth while using only one common baseband path thanks to an intentional analog signal overlay. Test structures of the RF and baseband parts were realized in a 1.8V, 150nm RF-CMOS technology packaged in a QFN48 housings with full ESD protection. Both chips are described in detail regarding their design and their actual measurement results

Instruction set extension for software defined radio in mobile GNSS applications

“…Besides the cos and sin values, the returned sample contains also their negation to simplify further multiplication with generated code samples. The final incrementation step also takes into account the entered discriminator value (2 …”

“…The frequency diversity offers an improved protection against jamming and interference, and provides faster navigation message reception. On the other hand, a multiband reception requires higher bandwidth and sampling rates [2]. To minimize this inconvenience, vast majority of the GNSS systems share common frequencies and CDMA multiplexing techniques.…”

“…A growing number of the integrated analog front-ends, which are capable of simultaneous support of multiple navigation systems [1,2], increases the need for flexible processing algorithms. Programmable hardware platforms, which support the SDR concept, can easily keep up with the latest algorithms implementations and support multiple protocols and standards.…”

“…Recent state-of-the-art integrated GNSS front-ends are capable of simultaneous support of multiple navigation systems [1,2]. A unification of the signal processing part is also possible and, what is more, desirable.…”

Reconfigurable architectures for GNSS receiver

“…In commercial receivers, ASIC's are utilized to handle the down conversion and digitizing, and to carry out massively parallel correlation function, while microprocessors such as ARM processor are used for baseband signal processing [14]. Present technology allows for a higher level of integration: Rugamer et al [19] talks about an integrated overlay ASIC based Multi-GNSS frontend; and the receiver explained in [15] integrates a whole GPS receiver on a single chip and needs only an active antenna, a crystal and few passives components. The low cost GNSS baseband ASIC chip receiver [20] greatly reduces the GNSS system cost because of the OpenRISC soft-core CPU.…”