# NaviSoC: High-Accuracy Low-Power GNSS SoC with an Integrated Application Processor
## 5 Conclusions  
The main concept of this work was to integrate a dual-frequency, multi-system GNSS receiver into one integrated circuit. In the introduction, it is explained why this integration provides improvements in terms of both precision and reliability. The SoC was designed in a 110 nm ultra-low leakage device with an aluminum metal stack. This is cost effective but poses technical challenges. It was shown that even using such technology, it is possible to achieve state-of-the-art parameters. The receiver covers both L1/E1 and L5/E5 bands for all available GNSS signals with the channel bandwidth configurable from 8 MHz to 52 MHz. Due to the design architecture used, the noise figure can be maintained within the lowest range compared to the existing solutions which have the highest bandwidth. The implemented dual-frequency GNSS AFE is highly configurable in terms of center frequency, channel bandwidth and ADC sampling rate, to customize the CCNV1-A1 positioning accuracy performance vs. power consumption for different types of applications. The accompanying GNSS-ISE baseband engine comprises highly configurable tracking-loops as well as versatile PRN (pseudo random noise) code generators (primary and secondary) to cover all mentioned GNSS systems. Currently, navigation software covering acquisition, tracking and positioning is being developed. The final SoC version including advanced power management has been designed.  
**Author Contributions:** The work presented in this paper was a collaboration of all Authors. Methodology, investigation and validation of RF and analog design, visualization, writing--original draft preparation, T.B. (RF system architecture), K.S. (specification, LO design--ADPLL control), P.N. (power management, current and voltage references, POR design), A.B. (power management, DCDC converter), I.B. (LO design--DCO), D.P. (RF design--LNA, balun and mixer), S.R. (clock generation design), L.W. (IF design); methodology, investigation and validation of digital design, visualization, writing--original draft preparation; K.M. (microprocessor and GNSS baseband), A.L. (SoC floorplan, backend and sign-off), M.P. (microcontroller peripherals and flash controller); supervision, writing--review and editing, project administration, funding acquisition, W.A.P. All authors have read and agreed to the published version of the manuscript.  
**Funding:** This work was co-funded by the European Union from the European Regional Development Fund under the Smart Growth Operational Programme 2014-2020, Sub-Measure 4.1.4 Application Projects under grant no. POIR.04.01.04-00-0101/16.  
**Conflicts of Interest:** The authors declare no conflict of interest.  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Parameter**} & \multicolumn{4}{c}{**Values**} \\ \cline{2-5}  & **Ref [(9)]** & **Ref [(19)]** & **Ref [(17)]** & **This Work** \\ \hline Process & 40 nm & 55 nm & 65 nm & 110 nm \\ \hline GNSS bands & Galileo E1, GPS L1, & Galileo E1/E5 ab, & & Galileo E1/E5a, GPS \\ (simultaneous reception) & Galileo E1, GPS L1, & GPS L1/L2/L5, & & Galileo E1/L5a, GPS \\ (simultaneous reception) & BeiDou B1, Glonass L1 & BelDou B1/B2, & & L1/L5, Glonass L1 & \\  & & Glonass L1/L2 & & QZSS L1/L5, IRNSS L5 \\ \hline IF bandwidth & 2–15 MHz & 2–20 MHz & 14/20 MHz & 2–52 MHz \\ \hline NF & 2.1 dB & 1.92–2.5 dB & - & 2.3 dB \\ \hline Maximum Gain & 78 dB & 116 dB & - & 131 dB \\ \hline ADC resolution & 9 bit & 4 bit & 4 bit & 1/Q 3 bit \\ \hline ADC sampling rate & 66 MHz & - & 74 MHz & 8–64 MHz \\ \hline Phase noise at 1 MHz & \(-\)94 dBc & \(-\)112 dBc & - & \(-\)121 dBc \\ \hline SRAM/FLASH & -/- & - & 1 MB/- & 512 kB/768 kB \\ \hline RF/SoC area & 0.25 mm\({}^{2}\)/6.4 mm\({}^{2}\) & 8.4 mm\({}^{2}\)/- & 4.5 mm\({}^{2}\)/22.5 mm\({}^{2}\) & 4.5 mm\({}^{2}\)/34 mm\({}^{2}\) \\ \hline RF power consumption & 16 mW & 36 mW & - & 35 mW \\ \hline \hline \end{tabular}
\end{table}
Table 1: Comparison with previously published multiband GNSS receivers.