## 4 Data Set Generation and Processing
### Test Bed Setup  
The test bed is composed of the following equipment and the overall setup of the components. The transformation of the GNSS signal in space to the GNSS receiver's artifacts (i.e., \(C/N_{0}\)) values) is shown in Figure 3.  
Figure 3: Test bed setup.  
The system includes the following:  
* Hardware component USRP X410, which is the primary GNSS recording and playback system, configured with a custom LabVIEW-based application. Labview is a graphical system design and development platform produced and distributed by National Instruments. National Instruments is based in Austin, TX, USA.
* Hardware component X310 (interferent signal generation) is utilized with GNU's Not Unix (GNU) Radio on Ubuntu to generate diverse interferent signals, including Gaussian noise, narrowband chirp, and wideband chirp.
* Variable attenuator precisely controls the power level of the interferer.
* Software component Windows Platform LabVIEW-based application with standard LabVIEW driver based on USRP Hardware Driver (UHD) was chosen for its compatibility with the X410 Universal Software Radio Peripheral (USRP) and for the implementation of bit-depth reduction.
* Software component Ubuntu Environment GNU Radio is used for generating the interference signals.  
The Software-Defined Radio (SDR) platforms are key components of the test bed and they are briefly described here. As described above, two SDR platforms are used in the test bed: the NI-Ettus X410 USRP and X310. The X410 is a new high-performance platform that builds on the success of the previous generation of USRPs, such as the N210, N310, X300, X310, and NI-2944r. This model is implemented with a new FPGA-based architecture that provides up to 400 MHz of instantaneous bandwidth per channel, which is twice that of the previous generation of USRPs. In addition, the X410 communication element includes two QSFP28 ports, which are able to support data rates of up to 4 \(\times\) 25 Gbps, which provides significant support for high-speed data transfer and communication. The X410 analog front-end includes the ZBX two-channel superheterodyne transceiver, which supports frequencies ranging from 1 MHz to 8 GHz. It is an improvement in comparison to its older USRP counterparts thanks to the the implementation of a double intermediate frequency (IF) architecture, encompassing both intermediate (IF1) and baseband (IF2) stages. This design mitigates the DC offset problem associated with older zero-IF devices. In other words, unlike the X310's zero-IF approach, the X410 eliminates the potential issue of an undesired carrier component acting as an unintentional GNSS jammer. This, combined with its improved sensitivity and dynamic range, makes the X410 ideal for faithful recording and playback of GNSS signals, ensuring the integrity of our study. In this setup, the X410 is used for the collection of the GNSS signal with 16 bit and the consequent playback with different bit-depths as described in Section 4.3.  
The X310 is a high-performance, scalable SDR, which combines two extended-bandwidth daughterboard slots covering DC 6 GHz with up to 160 MHz of baseband bandwidth. In this study, only one of the ports is used. The X310 is used to generate the interference signals described in Section 4.2 using its zero-IF architecture. The X310 output gain is kept constant throughout the experiment to ensure that the interfering signal always maintains a consistent power level not greater than \(-\)50 dB over the entire 10 MHz bandwidth.