## 1 Introduction  
Currently, most Commercially Off The Shelf (COTS) receivers available in North America only support GPS L1 C/A, while some also support GLONASS L1 OF and WAAS L1 augmentation, thanks to their integration onto a single chip [1]. As new Global Navigation Satellite Systems (GNSS) are becoming available, this trend may change. Indeed, both the Chinese and Russian governments have passed laws mandating that all receivers sold in their territories be compatible with their national systems, _i.e._, BeiDou and GLONASS, respectively [2, 3]. In parallel, mobile devices (e.g., smart phones and now wearables) have also known an exponential growth.  
On the other hand, higher-end receivers also support differential correction and semi-codeless tracking of the encrypted GPS P(Y) code available on L1 and L2 for improved accuracy, such as in precision farming and land-surveying [4]. Over the last decade, dedicated resources for signal-customized channels have led to receivers with more than 200 tracking channels--not to be confused with effective acquisition channels obtained through FFT-based approaches or \"fast acquisition channels\"--such as [PERSON]'s [5]. These two trending markets (namely low _vs._ high end) have conflicting development paradigms: affordable battery operated _vs._ expensive and power-greedy devices.  
Thanks to the modernization of GPS and GLONASS as well as the advent of Galileo and BeiDou, new signals are being broadcasted, or at least should start being transmitted shortly. These signals aim the answer the traditional GPS limitations. Indeed, higher bandwidths will help resist interferences by diluting the impact of a narrowband interference over a larger bandwidth [6]. This should also provide better positioning accuracy and resistance to multipath with a faster chipping rate [7], thus requiring a smaller correlator spacing and a higher sampling rate. Longer codes will increase signals' cross-correlation protection and their robustness in weak signal environments. The multiplication of active satellites will increase availability, while integrity should be improved through more detailed navigation messages and deployment of new control stations, as well as new generation satellites with improved on-board clocks. This context calls for implementing new robust acquisition and tracking architectures, in a compact design, that are capable of harvesting all the potential of these new signals. Indeed, considering over 530 civil GNSS RF signal components (namely data and pilot) available worldwide, half of which being visible to any ground-based user, the importance of reducing the total complexity while maximizing global robustness and precision becomes more than desirable.  
This paper novelty relies on a GNSS receiver system based on a multiplicity of the proposed universal GNSS acquisition and tracking channel based on the optimal correlator approach (_i.e._, matched filter ([8] (Chapter 10), whose aspects are further discussed herein:  
1. A dual-component (AltBOC-ready) apparatus;
2. An improved Dual Estimator code discriminator;
3. A time-multiplexing code module;
4. A secondary chip wipe-off (for longer coherent integration);
5. A configurable sub-carriers and code clocks combination module derived from a single Numerically Controlled Oscillator (NCO) master clock and
6. A sub-carrier time-multiplexing with weighted sub-carriers combination module.